Sigma 18-35 f1.8 review

[@TonyAndChelsea]

Redzo79 Your misunderstanding is a common one, though your attitude could be nicer. I'll have a video out tomorrow that will clarify it for you. Obviously the light per square inch is the same, but smaller sensors have fewer square inches... so the light per pixel (given the same number of pixels) is lower, and light per pixel is the biggest factor in image noise.

[@toefurcub]

Tony Northrup do full frames generally have less noise?

[@TonyAndChelsea]

Yes, at a given ISO, because the larger sensor is gathering more total light and more light per pixel.

[@VladimirAWegner]

Think about a photo cell like a well, where electrons are floating. An electron can get out of the well by photon, or by itself due to its energy. The former is a useful signal, the latter is a noise. The less photo cell is, the less the well is, and it requires less energy for an electron to escape. Thus, small photo cell are noisy by their nature. Hope this analogy helps

[@toefurcub]

does this noise also translate into photos in full light as opposed to in the dark?

[@VladimirAWegner]

Yes, when there's no photons, the only current is caused by electrons escaped from the well. Another notice, the large temperature there is, more electrons will be able to escape the energy well. This explains, why the signal becomes noisy with very long exposure times; the matrix is getting hotter. The same applies to video shooting, the matrix may become hot, and the image noisy.

[@jonesey65244]

I generally learn something from your videos, but this time, I REALLY learned something important I did not know before. That is that you also have to multiply the Aperture as well as the focal length. I've watched many, many instructional videos, and you are the first one who has pointed this out. Thank you; for the tips, and the hard work you and Chelsea and crew put into these.

[@TonyNomadic]

That definitely was an eye opener

[@legoEndeavourStudios]

@@MPD90 that makes no sense whatsoever

[@arghasphotos]

@@MPD90 ?

[@IvanToman]

You don't need to multiply neither focal lenght or aperture. Lens is lens, those numbers are their physical properties, that does not change if you put them in front of different sized sensor in any way. What does change is field of view of resulting image, that is narrower on crop sensor than on full frame. This narrowing of FOV, in order to keep same subject framing, require photographer to physically move further back, that is, to take shot from larger distance. When image is taken from larger distance, in order to keep same subject framing, you get deeper depth of field on subject distance and that resulting DOF looks like DOF taken from shorter camera-to-sobject distance using smaller aperture...

[@SiliconEngineer]

@@IvanToman If you’re using a full frame lens on a APS-C sensor, then you have to divide the aperture of the lens by the crop-factor, since the smaller sensor is not able to utilize the full image circle of the lens. Like you said, the FOV is narrower, but the effective aperture of the lens is also lower.

[@davidduffy9806]

Tony, many thanks for this excellent review of the Sigma 18-35mm. Last weekend I purchased a Nikon D7200, I am visually impaired (aka blind) though I still have useful vision. I have been ruminating over what lens to pair with the D7200 and your review makes it clear a marriage between the D7200 and the Sigma 18-35 would be a perfect match. If your wondering why a visually impair person would buy a camera as expencive as the D7200, the answer if WiFi. Using live view and Dashboard my focusing and framing view become the size of my monitor 23" ! So as crazy as it seems, that a white cane user would be behind a camera, the brilliant tech that's feeding through photography make "blind photography" possible! Again many thanks for your review and this coming weekend I will be purchasing a Sigma 18-35. Cheers David

[@shaxtv6455]

david duffy have any problem with AF on ur nikon d7200 with sigma 18-35?

[@nikosadie]

I got this lens at a really good price and I love it. I mainly got it for astrophotography. At 18mm (29mm Equivalent) it is just wide enough to get decent landscape shots of the milky way. At 35mm (56mm Equivalent) it works really great in portrait mode for shooting panoramas of the night sky. The main thing is the f1.8. It lets in a ton of light so I can speed up my shutter a bit and avoid star trails or I can lower my ISO for less noise. I have taken a few normal landscape shots and it is quite sharp. It is quite heavy for a crop sensor camera use and there is a tiny bit of focus noise, but I do not shoot video and if I did, I would probably use off-camera audio. The lack of IS is not an issue, since I usually shoot wide and since the lens is so heavy, it tends to be a bit more stable and the wide aperture lets you use faster shutter speeds. Build quality is brilliant. The short focal range could be an issue for some but if it works for you then this is a great lens.

[@PauloMiguelLarracas]

I thought I was watching Dr. Strange reviewing a lens in 2019.

[@nerdragingSC2]

After End Game, he really doesn't have that much to do anymore

[@desmondmacnamara6068]

I was just thinking Tony looks like an evil magician here.

[@Chasing-Wisdom]

Lol, sound pretty damn right

[@yusriplanner4666]

Same here

[@Horatio-Monroe]

It is.

[@valentinheimhuber107]

Great fully professional review, thanks! The only review of this lens that acknowledges that you are actually getting an aperture of around 2.8, rather than 1.8 at fully open. Crazy that none of the dozens of other reviews on youtube talk about this.

[@moviewatcher1024]

Tony FYI - the aperture of a lens does not change with sensor size. So if you have a 2.8 lens on a FF body you still have a 2.8 lens on a DX body. Only the effective focal length and FOV changes. Please make a note of this.

[@TonyAndChelsea]

I have an upcoming video that will explain it further. As I mention in this video, it doesn't impact the exposure settings, but applying the crop factor to the aperture will allow you to more easily compare the depth-of-field, total light gathered, and light gathered per pixel (and thus noise levels).

[@Macsnapshot]

One of the reason I always come back to your reviews Tony is that you are not bias and not pro selling in favour for the camera & lens industry . Too many reviews done by photographers on KZbin to promote their products for promotions. I love your vids . You are both beautiful . Thank you for all the info . I learned a lot from you both !! :)

[@thinhvcoin]

Your wish came true I think, Sigma just introduced the 50-100 F1.8, not quite 70-200 but omg look at that aperture. Do look forward to see your review on that lens

[@TechHints]

Watching the video after 7 years, still makes sense though. Going to buy this lens. Thanks Tony for such a detailed review 😊

[@DeyvsonMoutinhoCaliman]

I can't believe it is a true f/1.8 for APS-C, this lens is like a dream. I saw this video years ago, but I couldn't appreciate at the time how good this lens is.

[@Kadacha]

I love how excited you look when you talk about cameras. Thanks again for all your work!

[@TonyAndChelsea]

+bash5995, you only need to use the crop factor for the focal length and aperture when comparing it to lenses designed for other sensor sizes, such as full-frame lenses.

[@Geert890]

@Tony Northrup Why not buy an EF/Full frame lens and use it on an EF-S/APS-C body?

[@saeedmatar2291]

+Geert Boer because it fucking costs allot and not everyone can buy it.

[@astika81]

+Said Matar umm the Sigma is the price of Full frame lenses. you could easily buy a Tamron 24-70 F2.8 with VC for the price.

[@saeedmatar2291]

Rami Bahrani why would you buy a full frame lens on an apsc camera ?

[@astika81]

Because a full frame lens is compatible with both and allows me to upgrade in the future without having to reinvest in lenses however I own the sigma I was just pointing out that it is as expensive as full frame lenses of not more (eg canon 24-105L is cheaper)

[@JohnGilbert49]

Tony, glad I found your You Tube link. I have been watching your video's for two days now and have shared several with several on-line photo-clubs that I belong too. To support this sight I also purchased the Kindle version of your DSLR Book and your Buying Guide. Been into photography for years but always enjoy reading new books and to see how different people approach the subject of photography. Heading to my favorite National Park, Yellowstone tomorrow and plan to read them on the way out there, (21 hour drive) when I am not driving. Your subject knowledge is excellent and you have excellent presentation skills. Easy to follow along. Enjoy Tony and Chelsea Live, you two are a hoot. Beautiful people. Thanks for sharing your knowledge.

[@TonyAndChelsea]

Thanks, John!!

[@TimothyGoetz]

OK. Just got this lens today. Been using it for about an hour. Would it be ridiculous for me to say I'll never pay for another Cannon lens again? This is my first "non kit" lens purchase so maybe my point of reference is weak. Love this thing! Thanks Tony!

[@TonyAndChelsea]

Yeah, the new Sigma Art lenses are far better quality than most Canon and Nikon lenses... but many of the standard Sigma lenses aren't nearly as good.

[@JonPaulKersey]

Man you are the the most amazing photography person on KZbin. I learn from you in every video. I love love love your content. Thanks Guys!

[@davidmorrie631]

I understand this isn't a portrait lens but I'm sure at 35mm (x1.6) 56mm wouldn't be that bad as some people use 50mm for portraits. I just bought this lens more for video but just every day shooting as well.

[@danielpalma3804]

David Morris I was Thinking the same. How is the lens for portraits at 35mm(x1.6)? Comparable quality/bokeh to a full frame w/50mm lens?

[@jamesr6497]

@@danielpalma3804 Good point and the answer is it isn't. There is no getting around the fact that the larger sensor is going to deliver superior resolution, less noise and greater dynamic range. DX shooters thinking their going to get a free lunch are just kidding themselves, especially if the want to blow up gallery size selling landscape prints.

[@jimmybartlett5864]

@@jamesr6497 Not so. Try the Nikon D500. It will give you excellent resolution, low noise, and wide dynamic range comparable to a full frame body.

[@higgenbotham]

I completely agree with you, Sigma should come out with a f/1.8 50-150 Sport lens so APS-C cameras can shoot pro level portraits. I am hoping that Sigma's discontinuing of the 50-150mm f/2.8 earlier this year means they are going to make a new one in their S sports lens lineup. Hopefully we will see it in photokina in a few weeks.

[@KocaMetallec]

GREAT review! I'm just wandering how this lens compare to the Sigma 35 f/1.4 A in terms of image quality and sharpness> ?

[@MarkNiceyard]

Yeah, that's a very nice lens. I sporadicly shoot with it on my 70D on family events and I love it. It's just so fast at dim light I don't need no flash. Great development by Sigma!

[@lysterb]

It's the first time I've heard that there is a 1.6/1.5 multiplier also for apertures. Sure , I knew that the DOF was narrower on FF but never knew this multiplier ! Thanks

[@Ridiqiulas]

I dont think there is a multiplier for apertures, its only for the DOF. I was searching the comments if anyone noticed what he said lol.

[@syxxphive126]

Kirk Corrie you absolutely have to multiply aperture as well! F/1.8 will always be F/1.8, but the overall performance of a 1.8 lens on a crop body will give the same image quality as 2.8.

[@PostColorGear]

I had the same problem with my Sigma, different lens. If you angle it and pinch it just right, it locks in, but other than that, Sigma may need to redesign where the lens cap attaches, in my opinion. It's nice to hear that someone else experienced a similar issue.

[@jessemao9927]

Many many thanks for your excellent review！！！But I believe that the aperture of aps-c is equal to the full frame, which has been confirmed from your comparison.

[@houcinesinaceur5170]

Yeah exactly not sure about that part being true either

[@Neil3D]

I've just bought this, after using the cork sized panasonic kit lens for a few weeks... this thing makes me smile every time I look through it

[@MrTacticalinuit]

Am I the only one who thinks vignetting can look pleasing?

[@canpin]

Lasse Anton i actually put vignette in ps in some of my fav pics 😂

[@MrYoyojuan]

MrTacticalinuit not at all, I've actually got this lens and have taken a couple of pics that I find very pleasing, it was on a full frame camera too so the vignetting was very heavy

[@YounanPhoto]

Yes. But it should be a choice. Not imposed on you. For example it sucks for Astro

[@Slayer1111111111able]

No, but it is easier to add vignetting in post than remove it. Less vignetting provides greater flexibility without sacrificing quality,.

[@SheilaHouse]

I know what you mean. Had the same thought.

[@nerys71]

WOH. I did NOT know the crop factor also impacted the aperature!!! I tend to shoot FF but also keep a 7D for that little extra 1.6 factor reach. SO this won't work on an FF ?

[@christianholmstedt8770]

It is a DX specific lens. It will not illuminate all of the full frame sensor. I just picked up this baby and it's spectacular.

[@MarcoCarpinella]

This lens is still the best option for APS-C in 2019?

[@parkiel54]

Why do you have a question mark after your own opinion

[@jamiewellington6208]

@@parkiel54ParkieL probably means he's asking a question?

[@ogjbot]

@@parkiel54 why do you not have one after your question? 😐

[@richmck007]

Marco Carpinella Yes. most definitely as sharp as when it came out. The only lens in Sigma’s range that are sharper are their prime lens when compared to this. The down side of this lens is that it is NOT a full frame lens and it is heavy! But then, nothing is perfect but this is close to as possible paired with the canon 70d and 80d and even the 7d mark ii. No questions nor interrogation marks needed here! ( opps...I went for an exclamation mark instead ..! )

[@jamiewellington6208]

@@richmck007 can confirm its a great lens just picked it up a couple weeks ago. if its zoom range was maybe a little longer to say 50mm and if it had stabilization it would be the ultimate lens, but I'd say its definitely worth it for film making.

[@keithbrown454]

Tony, I must say I think you was at your prime while reviewing and doing this video. I like your presentation and the whole review delivery of the this lens. You was analytically detailed about the lens. I am looking to purchase this lens and enjoyed the whole video. Thank you.

[@jasonfields6514]

If you use an apsc lens on an apsc body do you still have to use a 1.5x crop factor for field of view & do the math for aperture as well??..

[@jasonfields6514]

Yes, you can change the aperture settings manually in your camera on this or any other electronically controlled lens. On the other hand I've been told by some that apsc lenses are already engineered to show accurate field of view & aperture on apsc bodies but some, like Tony, say you still need to factor in a crop & aperture difference.. I'M CONFUSED!! lol

[@Jaibuuuu]

For aperture: yes if you want to obtain light gathering equivalence (a FF f/1.8 hole is simply bigger than a crop f/1.8 hole ) , no if you want to obtain depth of field equivalence( the depth of field depends on the lens no matter what's your sensor size, the bigger the projection circle, the swallowed the depth of field at the same distance) .

[@okaro6595]

The type of the lens does not matter, only the body. But if you do not have a FF camera as well as a crop you really do not need to use the crop factor. You can just learn what your system can do. Only when you hear or read from others who use FF you need to adjust.

[@okaro6595]

Jason Fields. Yeah, you are confused, what you said is nonsense. The accurate ins are 18-35 mm f/1.8 for this lens and so on. These are the real, true and only focal lengths the lens has. Now if you want to compare results to an FF body you can use the equivalences. Lets say you have a Canon crop and you see a photo that has been shot at 40 mm f/2.8 and ISO 400 on an FF camera, you need to calculate different values for your camera. You need to divide the first two by 1.6 and the second by it twice. You get 25 mm f/1.8 (1.75) and ISO 160 (156.25). You can produce that same result with this lens. If any of the results fall outside the range your lenses or body can produce then you cannot produce exactly the same results and you have to do the best effort by using for example the widest available aperture or lowest ISO (of course there can be also other differences, a pro system just can be better in ways that are not always obvious by calculating).Note I said decide and Tony talks about multiplication. It is a matter of perspective. He uses normally FF. He is familiar what it produces. You use crop and are familiar on it.Only in compact (fixed lens) cameras can the equivalences be actually be printed on the camera. Fortunately at least Canon seldom does that. On Interchangeable lenses the figures are always real. Otherwise it would be very confusing to mix FF and crop lenses.

[@jasonfields6514]

Okaro X What the hell do you mean??.. & why do you keep responding to me weeks later? I guess I should have tagged Tony in the question because I wasn't asking you anyway! In my original question and my first response to the other guy who asked a question, I intended to say FIELD OF VIEW instead of focal range. Sorry for being human!! Does that make sense to you??? I've often heard that lenses that are engineered for aps-c sized sensors are already engineer to show the correct FIELD OF VIEW. On the other hand, I understand that if you use a full frame lens on an aps-c body that you have to do the math to figure out your correct FIELD OF VIEW and aperture . I was just trying to get an understanding on whether manufacturers actually make aps-c lenses to show the correct "FIELD OF VIEW" & aperture settings as full frame lenses show on full frame bodies or whether a conversion still needed to be made. For example, I own a Sony a6000 and a6300. both of these are aps-c bodies that came with a 16 - 50 millimeter f3.5-5.6 kit lens. my question for the last time! is... do I still have to do the 1.5x crop conversion even though this lens is engineered for an aps-c sized sensor. I.e., is the 16-50mm FIELD OF VIEW really 24-75 with this lens, or is it the same 16-50mm field of view that I would see on a full frame camera with a 16 - 50 millimeter lens engineer for full-frame sensors?? I think that's pretty simple! I couldn't go back and edit my comment on my phone. I didn't mean to say focal range but FIELD OF VIEW! I apologize for my stupidity LOL! I'm not sure how you got nonsense out of all of what I said but since you couldn't comprehend, just let someone else answer the question who can. Have a nice day Okara X!

[@MrEye4get]

Wow! Definitely worth considering. Thank you for explaining the technical aspects of cropped and full framed cameras as well as lens aspects. I learned so much!

[@mmartini9573]

Please, would you recommend this lense on entry-level cameras like a Nikon D3300 or it would be better use this lense only on APS-C high-end models like D7200 ? Thank You.

[@lehmyoouhl]

this lens is for dx/aps-c, so why not?

[@jose280714]

M Martini I just bought it...for D3300 Nikon

[@atifbaig7598]

Hi tony, interesting observation: sigma 18-35 on nikon 7100, its behave as 27-53 f 2.7 and when u use crop 1.3 it field of view actually reach to 68mm with f 3.6. Which is actually almost equivalent to nikkor 24-70 f 2.8 at less than half price

[@victorshcherbina7323]

I am now accepting donations for me to purchase this lens:)

[@DJaySplitSecond]

Victor Shcherbina Lol I have this lens and it’s my fav, now I want the 1.4

[@PaulGillingwater]

An excellent review from a photographic perspective. I want to add that as a filmmaker, this is a superb lens, especially when used with the Metabones Speedbooster on a Panasonic GH2/3 or BlackMagic camera. The crop in MFT is 2:1 (or smaller with the Pocket), but this is somewhat offset by the 0.71 reverse crop of the Speedbooster.

[@STEHH87]

Well 35mm times 1.6 also does not equate to 70mm... Of course the DOF is shallower on the Full frame... You guys should have compared it at equivalent focal lengths (35mm APS-C and 56mm FF)... this is not an accurate test!!!

[@TonyAndChelsea]

+STEHH87 We compared it against the closest comparable gear. This is a lens comparison to help buyers make decisions, not a discussion of sensor size.

[@rbettancourt]

Tony & Chelsea Northrup could you elaborate on this, please? This is exactly the first thing I noticed when I started watching this video. Thanks!

[@MchalesNavy]

@Rolando Bettancourt +@STEHH87. He noted it right on the video. The tamron suffers from focus breathing, means that zoomed into 70mm, you're not actually getting the full 70mm. Focus breathing occurs because the focusing elements are moving inside the lens. If the lens isn't designed well enough, when focusing on very close subjects the focusing element needs to move so much that it actually shortens the focal length of the lens. So with this tamron lens, 70mm focused on a very close subject means it only gets about 56mm of effective zoom. That's directly comparable with the 35mm sigma with 1.6x crop factor.

[@MrNyuntshwe]

Thank you so much Tony. I decide to buy the Sigma lens today after your lucid and adequate review. I am going to use it with my GH4 and will use Zhong-yi lens turbo adapter before I could spend Metabone speed booster. Thanks again.

[@melahodges]

I am looking to buy a lens for my Canon 7d and this lens seems to be a great option based on your review and others I have seen thus far. However, you mentioned this lens is not great for portraits as it might make "a nose look large or forehead bigger". I am by no means a professional photographer, however I do take photos of my little and also for friends and family from time to time. I wanted to get the Canon 24-70 but felt like that would be a waste as I have a crop sensor (Im glad you also mentioned this in your video). Long story short, I would want to use this lens for portraits, are you saying this would be a bad buy for this type of photography? Would you be willing to show me what you meant by the portrait distortions? Thank you!

[@joebuslife9275]

melahodges he's talking more specifically about real close up headshots where it's pretty much just the head in frame where this would be bad. You could still do non headshot Portaits. Just zoom to 35mm and get a shot with a 1.5x - 2x crop in editing in mind. The facial features/ field if view should turn out just like a 85mm or longer portrait lens does on Full Frame, and it will still be quite sharp.

[@johnmiller7682]

A standard portrait lens is usually 85mm. That means, on a crop censor camera, you'll need about a 50mm lens. That will give you almost 85mm. Now, if you're looking for a good zoom (and portrait) for a canon, look at the EF-S 55-250mm STM lens. 55mm gives you an actual focal length of 88mm, which is perfect for portraits. And this lens is amazing. Just make sure it's the STM version. The older version was awful. Now match this up with this Sigma 18-35mm and you won't need any other lenses. Unless, of course, you're looking for both a fast zoom. But then you're looking at glass that will run you in the thousands. I picked up my 55-250 for 125 bucks. And as far as quality for price, it can't be beat.

[@nitramwin]

You can go with the 50mm f1.8 STM lens which is quite nice for the money.

[@7reyes298]

Hi tony I have a question about this lens:Why do you still multiple for the APS-C factor ? Isn't this lens designed for cropped sensor cameras? Thanks and forgive me for my ignorance

[@2ndlifeclockwork758]

Definitely saved me from selling my kidney for that 24-70 lens I'd been eyeballing. Thanks for the tips!

[@armenkirakosyan]

Thanks, Tony! usging this for several months, I think it is fantastic with my D7100. Falling cap problem only when lense hood is on, strange, same for me. Also a lot of people including me complain about backfocus. Focus a little bit shifted and should be corrected with USB thing, I have corrected mine a little bit, and now it is perfect.

[@armenkirakosyan]

Here is the sample with Sigma 18-35 500px.com/photo/63467769

[@YourJapans]

Until today 2019, this lens is a killer.

[@rumporridge1]

Lens still kicking butt in 2020.

[@jdam28k]

2021 still trucking

[@YourJapans]

@@jdam28k I agree

[@gabrieltonatiuandrade8941]

I have a Canon t3i and have been saving for the Tamron 24-70mm f/2.8. You just convinced me to buy this lens. Amazing work, Tony!

[@Zhorellski]

They're not available on E mount?

[@RickyHarline]

No. You have options, though. You can buy an a6300/a6500 and get the cheap LAEA3 adapter and buy the A mount version of the lens. You can buy an older e mount camera and buy the more expensive LAEA4 adapter and get the lens in A mount. You can buy an A6300/A6500 in Canon EF-S mount and get the Sigmaa MC-11 adapter.

[@maxi-g]

it is now

[@aaronjonellhall1937]

You are so right about the Tamron 24-70 focus breathing. I noticed when going back and forth between the Canon 50 1.8.

[@TGLPYT]

I have the Canon 750d and use the 18-135 Kit Lense plus the 50mm 1.8 STM ... This would be A LOT of money for me, is it worth the improvement? Can someone tell me his opinion? :)

[@joebuslife9275]

TGLP depends, if you shoot indoors or in low light often then definitely yes. The Sigma is also just about as sharp as any prime available for apsc as well (way sharper than either of your stated lenses). if super portability is a main requirement of yours then maybe not. You can pick it up for $600 or less on Ebay though so if you sell any current lenses it wouldn't take to much money. All in all though this lens is absolute magic. It hits a sweet spot on size price sharpness etc. Just not that big of a zoom range, but the fact that it is class leading in almost every way, it's a miracle it zooms at all to be honest.

[@joebuslife9275]

Also if you zoomed the sigma to 35mm and then cropped to have the same field of view as your 50 1.8 it would be way sharper and better in almost every way.

[@sunkaikit]

750D is APSC, actually it is 80mm on his EF 50mm f1.8

[@rasalahmed1209]

Would you need to apply crop factor to the aperture of this lens if it's made for apsc?

[@TimothyGoetz]

Just ordered it. Thanks so much. It's my first "non kit lens" for my new 70D.

[@manualmind6384]

Tony, thank for your Reviews.... But...... You look like an asian kung fu grand Master in this Video ;D. Greetz!

[@jayplamenco6679]

Tony Northrup hello, loved the vid..you mentioned if sigma would make a similar telephoto such as 70-200 f2.8. I currently have a SIGMA 50-150 f2.8 OS. it is similar to 70-200 f2.8. I think it is wonderful and a great lens. I had the canon 70-200 f4L but i feel like i needed more. Would you be abel to look at this lens and have a review on it? Thanks a bunch

[@leojonkers3181]

Not true, een APS-C camera has the same DOF as an FF. It is the lens and distance that determines your DOF, it does not matter what kind of sensor is behind it. It is the same wrong way of thinking as saying that your APS-C camera makes you lens to have a greater zoom. You do not have to be a rocket scientist to understand that a lens does not change behavior if there is a smaller sensor behind it or that a smaller sensor gives you the exact amount of DOF as a FF sensor does. The only thing that happens with a smaller sensor is cropping, the rest is confusing and a wrong way off thinking.

[@TonyAndChelsea]

Leo Jonkers OK, but "only cropping" completely changes the picture. Obviously you're trying to get the same images regardless of your sensor size. I have a series of videos on this topic, but this might be a good place to start: kzbin.info/www/bejne/ZoDXepytl6aNn5o&lc=z13bfloj1k2ejxjch22nu1jyasrryeg0 (the other videos are linked in the description)

[@leojonkers3181]

Tony Northrup Thank you for your link, interesting. Cropping may "change" your picture by making it smaller FOV, the part that is cropped is exactly the same as the non cropped picture. If you want the same FOV with a cropped sensor as with a FF you get a different picture all together. It i impossible to make the same picture with the same FOV with a FF or an cropped size. In fact it is simple as can be. A cropped sensor crops, that is it. You can make it unnecessarily complicated and that is in fact what you do with using "equivalent" and comparing different lenses with the same result, witch can never be true. I understand the need to predict what the result will be on a cropped sensor in comparison with a FF. But in my eyes it is a wrong approach. Cropping is cropping, that is all there is to it.

[@zazauruszadze3609]

Leo Jonkers Tony's approach is more practical and useful

[@leojonkers3181]

Zaza Uruszadze It is not useful if you think a little further. It is wrong and it is much more confusing. But Tony is not the only one, this wrong way of thinking is wide spread.

[@forbesjeff]

Leo Jonkers It's not a wrong way of thinking. It's a way of approximating all of the image qualities, rather than just angle of view. It is a very effective way of comparing different formats and their capabilities. For example, I have a 45mm f/1.8 on my Olympus, and my FF lenses that cover 90mm are all f/4. I can approximate that in light limited situations, I will acheive possibly slightly better quality from my m4/3 prime lens than I will from my FF f/4 zoom, because I will be able to use an ISO that is more than 4x lower to acheive the same minimum shutter speed to make the shot - and it will do so with a hair less depth of field than my FF setup. An example of a situation where you might be able to compare the two would be inside an average living room at night, roughly ~ev12. FF: 90mm @ f/4, ISO 1600 1/100 4/3: 45mm @ f/1.8, ISO 320 1/100 That will give you a very similar quality level between the two images - possibly giving the 4/3 camera the edge. If you accept that a smaller sensor "just crops" the image, then follow this: If you crop an image, you are: 1) Decreasing the amount of light captured on the sensor 2) Decreasing the angle of view - aka a smaller focal length will achieve the same field of view 3) The depth of field is not changing. A 50mm lens at f/8 will have the same depth of field when focused 10' away, regardless of the sensor format. 4) f/2.8 is still f/2.8, is it not? It still achieves the same exposure time at the same ISO, right? Yes. So how do we get "there" from "here"? 1) If you want the same image, you need the same field of view. This is more important than anything. So with a crop sensor that "just crops", to achieve the wider field of view that the larger format camera is using, you need to use a lens with a shorter focal length. In the case of 4/3 vs FF (Because math is easy), a 25mm lens will be necessary to achieve the same field of view as a 50mm lens does on 35mm format. 2) So now we have the same perspective again, with different focal lengths to get there given the different sensor sizes. But now, a 25mm lens has more depth of field than a 50mm lens does when set to the same aperture and focusing distance. You will find that the 4/3 format will have a hair more depth of field, but not by much... if the aperture is 2 stops larger. 3) So now we have established an image that has the same qualities - angle of view and depth of field. How does ISO come in to play? In light limited situations, you're limited by shutter speed. Let's just ignore image stabilization and focus on the basics here. So now, we're 2 f/stops faster on the small format compared to the large one and have comparable depth of field and viewing angle. So now we need to match the shutter speed. Now you can do some simple algebra: 4/3: 25mm f/2 @ 1/100, ISO 800 35mm 50mm f/4 @ 100, ISO ???? f/2 @ 800 = f/4 @ 3200 In reality, it's a little bit more complicated than that. Smaller formats have higher pixel density in general, so you will get more detail per sensor size, but the sensor size itself will dictate how much light is collected, so image noise should be pretty comparable when the ratio of sensor sizes is considered, given that it has been proven that smaller sensors do not have significantly different noise levels from larger sensors.

[@MO-hq4iz]

It nice to finally see someone able to do the math about crop facto and f-stop, nice job Tony. PS: In a way you should use a crop factor in ISO as well, if you want to compare noise that is, it's all about gathering light.

[@SwisssblisS]

hehe.. just bought this lens yesterday :)

[@Clove_Parma]

Much jealous, I'm saving. How are you finding it after a month?

[@SwisssblisS]

I think this ist the best lens you can get for aps-c sensors :) love it

[@DeepakGupta-or5di]

Hi Tony, Am thinking of getting this along with 2 options for camera body: 1) Pentax K50 2) Canon T5i. I am leaning towards Pentax body since that would give me stabilization this lens does not have, however I have been past Canon user with 1-2 lenses around, so that is a more natural choice for me, am frustrated with Canon's lack of innovation and the 5 year old sensor. I was considering mirrorless but ruled that out since this lens is not available on mirrorless. So what would you advise : 1 or 2, Pentax or Canon from future growth point of view/value/lens options.

[@killjoyshidae1208]

Sigma actually has a 50-150 2.8 for crop sensors. However, it would be a 80-240 4.5 in full frame terms, and they just discontinued the Canon mount, which I find very disappointing (you can still buy it for $950-1100 though). I really hope they make something like a Art 50-150 1.8! That would really make my life a lot easier! The only other brand I know that makes similar APSC telephoto lenses is Pentax (50-135 2.8 and 60-250 4).

[@2chill2]

Tony, I love all your videos. One question: F1.8 should be 1.3 stops faster than f2.8. Why was the 70d in ISO 800 and not ISO 640 (1.3 stop faster than the 5d3's ISO1600? Maybe the 18-35's is more like f2?

[@deathspawn54]

Tony you say no one makes a good fast zoom for crop sensors until this one so you have to buy the 70-200 2.8 or the 24-70 2.8 but sigma has brought out multiple lenses for crop bodies, the 50-150 2.8(multiple versions infact) and the 17-50 2.8 and sure they arnt really 2.8, but if you buy the 70-200 2.8 as the pro lense then you cant say they arnt fast crop lenses

[@jasonadams7245]

Tony, thank for the review. I recently purchased the Nikon D7500 and am looking for a lens that won't break the bank for some golf course photography. I am looking for a high level of sharpness and like the f1.8 if I need to shoot in early morning or late evening light. I'd love to hear your thoughts if this lens is a good fit. Thanks, Jason

[@offthebanks168]

hey Tony not sure if you forgot to mention it but the actual focal length on this lens is 28-56 on the crop sensor i hear you should use lenses made for your sensor but this lens is made for crop sensors seems to have glass for full frame i looked at it on amazon and it states it as a 28-56mm i just dont understand lol

[@zachblah2858]

You made a point in this video to talk about the aperature on crop cameras also adding magnification as well. I found this interesting as I was only aware that this impact occurred in regards to the zoom on the lens. With that being said, most landscape folks talk about F8 - F11 being the sweet spot for capturing all details....Based on what you said, does that mean for my crop sensor camera that I should actually be in an aperature range of roughly F5.6 - F8 (in order to equate to the coveted F8 - F11 range)? Or if I have DX specific lenses on a DX body, am I good to go and don't need to worry about the 1.5X crop factor? Thanks!

[@KevinCorbett71]

Hi Tony. Thanks for all the great shows. So, I bought the Sigma 18-35 on the strength of you and others raving about the sharpness. I've found it less sharp, even at the f4 sweet spot than my 18-135 on my Canon 60D. I sent some sample images to Sigma USA tech support: essentially side-by-sides using the Sigma, the Canon 50mm 1.4 and the Canon 18-135. Sigma tech support responded quickly but without offering advice or any suggestion that the images suggested a problem to them. So, much as I want to love this lens, back it goes (and I take a 15% restocking-fee hit - Ugh).

[@TonyAndChelsea]

Kevin Corbett Strange! Sorry about that!

[@herebarian]

at 4:56 , when comparing with the 24-70, shouldn't you have set the focal length of that lens to around 55mm on FF to compare with the corresponding 35mm on the Sigma? Of course you will get a shallower depth of field on the Canon lens, because it is longer than the equivalent focal length on the Sigma lens. Do correct me if I am wrong.

[@jonathancaldentey4615]

I believe he explained this. Because of the Tamron focus breathing, when focusing to a close object, the 70mm actually works closer to a 56mm.

[@edwardrex6458]

I had a chance to borrow this lens and shoot it on a 7D, 1D Mark IV, and 5D Mark 3. Yes it is intended for crop, but unlike Canon's EF-S line it fits and works great with FF and 1.3 crop cameras. on the 1.3 crop there was some vignetting at 18mm but it was not bad. On the FF, lots at 18mm but gone by 22mm

[@willoughbykrenzteinburg]

I don't think you are talking about the same lens that is being reviewed in this video. It's focal length is from 18mm to 35mm, so it could not possibly have ANYTHING wrong or otherwise at 11mm.

[@shiwang8989]

I shot some pictures with 5D MKII, vignetting was gone around 24mm. But those pictures were not as sharp as on 60D. Also, when shot at night scene, pictures on 5D II were just not good. So I have this lens and Canon 135mm on my 60D and will use them on my coming trip to Chile, Torres Del Payne::=))

[@petronics2454]

Hi Tony, just letting you know that I love this lens. It's on my shopping list and I have tried it out on my D5300. A great compliment to the Sigma 18-250 DC MACRO.

[@yugen042]

I have this lens and I used it on my Sony crop camera (A77). Now I switched to an A7R2 and when adapting this lens to that full frame body, I'm not getting any vignetting as long as I don't go to the shorter focal lengths. I haven't checked the corner sharpness in detail yet, but so far it looks quite good.

[@jimwong2442]

Tony, Great review of the Sigma 18-35mm. I also learned a lot from your video. Thanks, Jimmy

[@hopkinsb4]

My old Pentax camera body renders the HSM lens to be Manual Focus and that's not what I'm looking for. So I am considering buying just one of the Sigma primes that you mentioned. Probably the 20mm f/1.8. I'm comfortable cropping down to 24mm or 28mm from here, so I don't feel like I need a collection of wide primes. (I do already have a 50mm f/1.4 for other purposes.) Pentax doesn't really have anything this fast for a wide lens. Any thoughts?

[@SunMaximus]

Can you shoot a portrait with this lens at 18mm and use Lightroom lens correction to see how it compares to a 50mm 1.8 prime lens. It would be interesting to see how things in post can be pushed.

[@aleximagday2085]

hi, i got your book HTCSDP months earlier, you caught my attention when you said this 18-35mm cropped sensor lens won't do good with head shots...i just did a 35mm head shot with this lens, and the picture looked good...anyways, it's just my opinion coz I agree generally that head shots are better done at lengths at least 85mm +? btw I'm just an enthusiast, and I'm learning Photography when I have some spare time...

[@KeiJikigorashipvblog]

Good video, however I noticed you compared 35 mm sigma with the 70mm tamron. At the time of reviewing the pictures the focal length of the cameras are different and not the same. What this means it’s that the a picture taken with a focal length of 70mm will have more bokeh the. 35mm

[@AgePix]

Great review as always Tony. I understand the crop factor but does that mean the aperture is also cropped even though this lens is a dedicated aps-c lens? So instead of this lens being a f1.8 it's really a f2.8?

[@merasanam]

Really great information. I have this lens but i am still very far from full frame performance. I am not able to produce crystal clear, full of intense colors and high contrast images. I am missing something? Or it's simply about the sensor ? Not to mention the sharpness. This lens is indeed sharp but i think a crop sensor cannot really take full advantage of it.

[@scubaphoto88000]

Tony - First of I enjoy this review. You say this is the only lens that is designed for the non full frame cameras. I am confused because Canon makes the EF-S series lenses. I would think a better comparison would be with this lens and the Canon EF-S 17-55 f/ 2.8

[@TonyAndChelsea]

I'm saying that this is the only lens that provides the shallow depth-of-field and per-pixel light gathering capabilities that full-frame cameras have had.

[@GinAmber]

Great video, I'm planning purchasing.

[@bluesmokegamer272]

Picked this lens up a couple months and been so happy with it.

[@ravindrashenoy5955]

Well done Mr. Norton, Chromatic Aberration is a vast subject and special branch of Optical Physics. You have explained it so simply with practical demonstration. Thanks a lot and Warm Regards.

[@yliu4093]

Hi Tony, I read your book and you highly recommend this lens. I am choosing between this lens and Nikon 17-55mm f2.8 for my Nikon D7000. Which lens is better for me? Most of time I do photography for my kid and family at home and on vacation. I also like to do have video for my kid. Thanks for your suggestion.

[@TonyAndChelsea]

Given the choice I'd go for the Sigma; there's no substitute for a fast lens, and f/1.8 is a big jump from f/2.8.

[@Mordeth0666]

Great videos Tony and Chelsea! About this lens, I hear they have had some focus problems. Did you need to calibrate it? Have people needed to do so often? And is it hard?

[@kubaposturzynski7137]

Hi, great test. I bought this lens for my Nikon d3300. I take pictures witch this lens indoors and in cloudy days. I'm an amateur and maybe I'm doing something wrong but in sunny days my pictures are getting a bit overexposed. I'm wondering to buy a filter hoya prond 8 for this lens so I can take pictures also in the sunny days. What do You thing ragout it?

[@jeffreyclarksonphotography9178]

Thanks for a great review! I am wondering how an extension tube and teleconverter would affect the properties of this lens. Specially the background defocus and compression in the image plane. I've learned from your videos that longer telephoto lenses compress faces and your say this makes portraiture shots more attractive. Could an extension tube have a similar effect? How about a teleconverter?

[@joeschmees4319]

Hey Tony, Great review with lots of detail but, your summary at the end left me wondering what the primary use for this lens would be. My interest was in using it on a D500 for Mountain Landscapes & family portraits. After the comment about not being good for portraits, I was expecting a comment on Landscape use. If not a good use for that, I struggle to see much use for it. Your thoughts?

[@sachinr0000]

Hi Tony, thanks for your videos. I always love them. Although I loved this lens & thanks to you for this lovely review! However, isn't the 18-35mm lens is equivalent to roughly 27-55mm on full frame? But don't you think the price comparison with the full frame equivalent lens of 24-70mm lens is not completely correct?

[@victorseastrom3455]

Tony, I've dropped in on your channel numerous several times and really enjoy your thoughts. I'm an old guy and have been shooting since my 4x5 Crown Graphic was new. (Chuckle). With great admiration and respect I have to say I think you might be wrong on the crop factor effecting the T stop. (2:40 in your video) The amount of light striking the sensor is the same regardless of the amount of crop. It's like if I stuck 2 1/4 x 3 1/4 roll film back on my 4x5 Linhof there is no adjustment necessary for exposure . If you set the T-stop at T-4.5 it will be T-4.5 no matter if its on a 16mm camera or 70mm camera. The only way it would have an effect on the light is if you used bellows or an extension tube for close-ups. I'm a director for 40 years now and have in the past gotten into many discussions Pro-ACs who don't understand that a 30mm is a 30mm no matter what camera or frame size it's on. The only thing that is affected is the field of view. All the best.

[@Zeroplanetz]

I still think I may end up with the 24-105 art. But it'll be used on a 60D. My thing is though is that It can stay with me through my travels from crop to full frame. And I tend to use more of a zoom style shooting.

[@RobertLeBlancPhoto]

+Zeroplanetz This would make a great wider/lower light companion to that lens. I have both and one could certainly NOT replace the other.

[@Zeroplanetz]

Yea but to start with one or the other. I'd choose the larger zoom one first for me. Then later maybe get this one.

[@RobertLeBlancPhoto]

That's exactly what I did.

[@Zeroplanetz]

MrCloudseeker Well I can see that. I do wish they would come out with a 24-70 f2.8 or better lens with image stabilizing for there keeping under 1k price range. That would hurt the other guys imo. But it is something I would dive too.

[@ron2117]

Hi Tony very informative. But also a little confusing. I am going to buy a sony 6500, and you recommend using apc lenses rather than full frame lenses. Could you recommend lenses that would be optimal . Thanks I was thinking of sony 55 1.8

[@johngaylord5921]

The best Canon-branded standard zoom for APS-C is the EF-S 17-55mm f/2.8 which has IS. I think that would have been the appropriate lens to compare to the Sigma.

[@jimmypalsson960]

Hello Tony. Just wana say that your site and video is amazing!!! I just bought the Kindle "how to create stunning photo. But where is all the videos? Best regards// Jimmy

[@TonyAndChelsea]

The 9+ hours of videos are accessed online (though we do have a DVD series/Blueray if you prefer physical media). The introduction will be helpful. Thanks for reading, Jimmy!!

[@jimmypalsson960]

Tony Northrup Hello again. I love the kindle version but i wana find the dvd also. But i cant find it on amazon. Can u link it to me? And what do i need to do for get my invite accept on facebook? Thanks for answering me =) /jimmy

[@GameFaceEnt]

I Have the Canon 70D and Love it but I really would like to have that Full frame 5D Mark III, but once I started seeing videos on this sigma lens I thought this might be able to satisfy me short term and this video really sealed that deal so Thanks Tony for a great review, I believe this lens just might be a God Send... cheers mate

[@TonyAndChelsea]

GameFaceEnt Thanks!

[@dwaggs32]

Hey Tony, I have purchased this lens based off of your raving reviews and couldn't be happier. I have one problem though, it seems lightroom doesn't have a lens correction profile for this lens. Have you had this issue? Is it just they don't have a correction profile for my specific Camera (D7200) and this lens combo or does lightroom not support the 18-35 f1.8 sigma at all? Thanks again, love your show!

[@michaelkung1640]

Hopefully I can get an answer here: I’ve been using this lens for about a year now on my t6i, loved it and never had a problem. Only recently it stopped autofocusing. It wasn’t updated or changed but I did later put it on the sigma dock to Make sure it’s on its latest version but still doesn’t work? Is this a common problem with canon body?

[@alessandrodp1029]

Nice reviewe as usual from you! I am going to but it to replace my Nikon 35 1.8 because I need wider focal for indoor shoots.Just one point as some people got this lens complain about autofocus inconsistency not solved with usb dock. What do you think? Have you experienced this?I am waiting for sigma 50-100 review as well. Please make considerations about the lack of stabilization that at the focal of 70-100 can be important? Could be better for the same price a Tamron 70-200 VC on an APS-C despite the lower maximum aperture 2.8?

[@kristianbenedictbayle1391]

Would this be a good lens for wedding photography? I dont have a lot of money to buy the 24-70 or the 70-200 lenses. Just started in the photography world. Would you recommend this for an amateur wedding photographer? Thank you. Awesome review!

[@ridewithriden3980]

Hi. Appreciate the great review. After watching this review, I am planning on buying this lens and I own a Canon EOS 77D. I've read of the lens's autofocus issue when shooting through viewfinder in newer models of Canon. Can you please advise if this lens will work on my 77D or not?

[@fawzyjify]

Hi Dear Tony Why you are against using this lens for portraits ? it is a 27-56mm equivalent focal length many people use the 50mm f1.4 on full frame camera for portraits, and this lens has equivalent characteristics, so why you think it is not appropriate ? Thanks for the advice !

[@TonyAndChelsea]

Joseph, check my recent test of portrait lenses (sdp.io/200test) for a discussion on the importance of focal length for portraits. Also check Chapter 6. People certainly do use a 50mm for portraits, and it'll let you blur the background, but the short focal length tends not to be flattering for facial features.

[@TheAndymuns]

I have the pentax DA* 50-135 2.8 it produces some very nice portraits.

[@timelord2222]

As I shoot mostly in live view, the focusing issues are not a problem. I'm going for total sharpness, and this lens delivers. Same as 50-100. When you shoot in live view, you focus directly on the main sensor, so no focus issues can emerge.

[@vinay47yt]

Hi Tony, thank you for this excellent review. I have almost zeroed in on the Sigma 18-35. However, I wanted to know your opinion regarding the three Sigma lenses (18-35mm vs 17-50mm vs 17-70mm). I mostly shoot handheld with primary interests being travel photography, landscape, family group photos and occasional portraits. Which would be the best according to you? Currently I own a Canon T2i with Canon EF-S 15-85mm + Canon 50mm lenses. I am also considering a telephoto lens, Canon 55-250 or Canon 70-200 f4 IS . Please share your inputs regarding these.. Looking forward to more of your videos.

[@shibui2466]

So, a f/1.8 lens is faster in a full frame than in a crop sensor?? Im so confused...

[@welles2002]

Hi tony, do you think the older 17-50 2.8 would be a better fit I have the Nikon D500 and thought the 18-35 would be a good fit but now im not sure ? you guys are awesome your videos are unbelievably informative .

[@ryanthomas9306]

welles2002 you have a Nikon d500 and want to buy a 300 buck lens ?

[@myspace04]

Hi Tony, Could you do a review of Sigma 30 mm 1.4 ART lens, please? And, if possible, compare it with Canon 24 mm f/2.8 STM and canon 35 mm f/2.

[@gerbest]

Best review, best explanation... Very happy that I found your channel... Thanks for the video... I bought this lenses 2 days ago and I am waiting them to arrive. Very happy to see that I did a good purchase... I also bought the Ef 24-105mm F/4l Is USM... I have a cropped camera T4i, and got this lenses to replace the one from the kit hopping that together they could complete each other... Being the Ef 24-105mm F/4l Is USM a FF Lens, the factor would give me a 40-170mm approx... Do you think that was a good choice?

[@GUNSESSION]

You have just earned a new subscriber because of your words of wisdom at the beginning!

[@TonyAndChelsea]

Thanks!