Camera Lens vs Refractor for astrophoto? FIGHT!!

Today, I'm comparing my Canon 200mm f2.8L (mark 1) lens against my Refracting Telescope (275mm f4.5), and see how the camera lens fares when doing astrophotography!
Note that this is just with a single sample of this lens - lens can have a lot of variability. And some lenses are generally better than others and exhibit almost none of the issues I highlight in this video (the Samyang 135mm F2 lens in particular is supposed to be excellent, and my sample of it certainly was).
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#astrophotography

[@qlifee]

You are answering my questions without even me asking, I can't be lazier!

[@CuivTheLazyGeek]

That's because I read minds :D Glad it was helpful!

[@davidaylsworth8964]

You could lazier but Cuiv would have to come do it for you. He too lazy to do that though.

[@NebulaPhotos]

Bad star shapes? UNFORGIVEABLE!! jk :) My hack to get rid of those blue and red rings on the stars with the Canon 200mm (or other lenses) is to shoot with a mono camera in narrowband, remove the stars from all channels, and then only add back in the Ha stars. All stars become white, but for narrowband (bi-color or SHO) I think it's a nice look. Credit: J-P Metsavainio for this technique.

[@CuivTheLazyGeek]

Hahaha :D Bad star shapes are a criminal offense? :) That's a nice trick! It feels a bit like cheating, but true, for pure narrowband it's not a big deal that all stars are white :D Maybe I'll try that at some point, thanks for the tip (and thanks to J-P too!)

[@centenojoel]

Great video, nice side by side comparison. This is such a relevant topic in our field and you did a fantastic job in sharing this info. Can't wait to get my L-Extreme filter (on backorder now).

[@ClearAmbientSkies]

I don't understand why there is such controversy around star shapes. I am an older guy, but a n00b though and still impressionable. Anyone care to comment? Great video Cuiv. I learn something all the time here. My trial to Pixinsight ends in November. I'll be purchasing it. Thank you for all you do.

[@CuivTheLazyGeek]

I think it's a feeling of perfectionism :) I can't deny that poor star shapes can detract from the overall appearance of an image but still...! Excellent to hear you're enjoying PixInsight - it is indeed quite a great tool! I will need to try out APP and Startools some more at some point. Clear skies!

[@toddnoseworthy1447]

So many videos in such a short period of time. Another great one for sure but I cannot keep up!! LOL. Keep'em coming. I will catch up eventually.

[@CuivTheLazyGeek]

Hahaha, sorry about that! Take your time :D

[@douglassmith1215]

With regard to focusing a camera lens, I found a nice cheap trick for my Canon 200mm f2.8 lens. Assuming the lens is held by a ring and then mounted on a small dovetail, you can cut a piece of 10mm thick foamboard (around 65mm long) and wide enough to wedge very lightly between the rubber focus ring on the lens and the dovetail (in the case of the Canon 200mm and the official Canon ring, the width is about 23mm). This essentially converts rotational motion of the lens to linear motion of the piece of foamboard. This turn out to be easier to adjust precisely, partly because of the added friction but also because linear motion is easier to control. In addition, the added friction prevents the focus from being inadvertently changed. It's not quite locked like a telescope focuser but it is certainly more secure. If you cut the foamboard too thick, you can squeeze it slightly to make it narrower. A very slight wedge shape is also helpful.

[@kenkoskela3357]

Interesting idea, Douglas! I had not thought of this... I appreciate the post.

[@douglassmith1215]

@@kenkoskela3357 An additional trick is to wrap the foamboard with a bit of Japanese Washi black masking tape. That adds a bit more grip and friction. You can add more layers until it's as tight as you like. The Washi tape is amazing stuff -- couldn't live without it.

[@kenkoskela3357]

@@douglassmith1215 Thanks for the input! :)

[@joseribeiro9564]

do you use this solution to do manual focus on the ring? For all my autofocus canon lens whenever i have my laptop available, i use the canon app with 200% magnification and use the manual focus arrows on the software, did you ever try that?

[@douglassmith1215]

@@joseribeiro9564 Yes, this is if you do manual focusing, if it's not connected to a computer. You're right, the Canon app is pretty good. If I have a computer or laptop available, I tend to use a specialised astronomy camera.

[@capturethephotons2078]

Awesome video.. This is the best new upcoming astro photography channel out. You are on the rise for sure. I see you at hundreds of thousands of subscribers like Trevor Jones and all those guys. Clear skies

[@CuivTheLazyGeek]

Thanks Joe! I think my channel may be too technical to aspire for such a large audience - people like Helena's Astrophotography are likely much better placed than me!

[@jeffbrennan5394]

Camera lenses and refractors was a comparison I was always wondering about. Thanks for answering this question.

[@CuivTheLazyGeek]

My pleasure! Of course I only compared one lens with one telescope - other lens designs (Samyang 135mm, Sigma 135mm, Zeiss APO, etc.) may have completely different results... but it's still fun to try it out!

[@pjf2583]

Hey, firstly amazing video. really helpful. One thing I notices (and you touched on) was the noise in the camera lens image. you mentioned that you got more stills from the telescope, do you think the end result of the camera lens image would be different (less noisy) had you had the same amount of stills for processing the image ?

[@celestromel]

Hi Cuiv, in your last vid, you mentioned USB - serial converter cables, particularly using the Prolific chipset. I had many problems with that approach (SW EQ 6N Pro) to my laptops - all resolved when I swapped to a cable with the FTDI chipset. I was told of a number of different versions of Prolific chips so it’s worth trying before buying if poss.

[@CuivTheLazyGeek]

Thanks for pointing this out Melvyn! You are right, and these days most adapters seem to use an FTDI chipset - the Prolific adapters I was referring to are the ones that are internal to Skywatcher mounts that have a built-in USB port! So unfortunately not something that can be changed easily...

[@michaelmistaken2863]

My AZ-EQ5, when using the internal USB/Prolific connection, seems to need an extra unplug-replug of the usb cable to get Nina/eqmod to connect. I might try to find an FTDI eqdirect cable to see if that’s more stable.

[@whatmattersmost6725]

1 more great vid Cuiv! Also a telescope optics have 2 or 3 or 4 pieces of glass, where as a Canon L lens has 7 or 10 or 14 pieces of glass! This proves that for astrophotography less glass the better and you proved it! All that matters is what you care about.

[@CuivTheLazyGeek]

Exactly - optimized for infinity focus or not, and for low chromatic aberration that really is the question! Lenses can be far more forgiving of a variety of issues, but can and do still work shockingly well for astrophotography!

[@jimtaylor5802]

Cuiv, Excellent, plain language comparison - good friend has gotten bitten by Astrophotography bug - he’s got a great camera and several lens - this will helpful in his journey. Please share the optical train components you used, including the filter drawer and adapters to connect a DSO camera to a camera lens. Sadly, his camera isn’t one supported by the ASIair Pro. He’s starting with a Panasonic G9 with a 300mm lens on a new/old Atlas EQG mount. Always enjoy you candor and wisdom.

[@CuivTheLazyGeek]

Thanks for the feedback Jim! Ouch, the astrophotography bug can endanger wallets and their owners, be careful! :) You can check the components of the telescope in my video here: kzbin.info/www/bejne/iqLZdoKkis2SpKs For the lens, I use an Astromechanics adapter, as well as a filter adapter that is unfortunately only available in Japan (from a company called Electricsheep). A workaround to include the filter in the imaging train is in this video: kzbin.info/www/bejne/g5zOmaqhjaaZhbc The G9 with 300mm lens on an EQG mount will be a great starting kit!

[@possisvideos]

the ol lextreme filter is a strict 2 color filter. to see all color abberations you should do a lrgb image...

[@CuivTheLazyGeek]

It is indeed a two bandpass filter, one in deep red, one in blue-green - so most color aberrations are still picked with such a filter! You are right though, a full LRGB workflow would make sure to catch absolutely everything, but I figured that this is a good enough approximation (based on my experience of using OSC with just a Luminance filter with that lens - pretty much the same result). Thanks for the feedback!

[@possisvideos]

@@CuivTheLazyGeek most camera lenses are optimized for blue and green. not for red, red ist rarely seen in the nature. APO camera lenses are optimized for red, green and blue. Older lenses are only optimized for green and have much larger focus spots and rougher surface - i tried a lot of them....www.possi.space

[@CuivTheLazyGeek]

@@possisvideos Wow, thanks for sharing this, I didn't realize that there was such a generational difference between lenses - it doesn't surprise me since green has always been the priority (Bayer matrix, center of the visible spectrum, etc.), but still, very interesting... Weirdly enough my old Canon 300mm f2.8 lens was extremely well behaved in red wide open, but showed that weird "haircut" aberration on green and blue... Thank you!

[@possisvideos]

@@CuivTheLazyGeek funny I have two old Canon FD300 f2.8 lenses (early EF have the same formula). If you focus to Ha they behave okay, but OIII is horrible...modern Lenses of course much better, the sanding technology is much more advanced, also no we have better glass choices and advanced optical formulas thanks selfoptimizing calculation algorithms on superfast computers... I cannot compare My Sony 135mm f1.8GM to an old 135mm. Lightyears of differences - its optimized for a 61 mPix sensor...

[@nathantw]

If you have Adobe Lightroom you could can display both images side by side and when you scroll around one the other will follow. It makes the comparison shots easier to see the difference.

[@sneakerset]

Well done ! I'm impressed with the comments regarding the Sigma ART 135mm. Thanks

[@CuivTheLazyGeek]

It's a very good lens indeed! Although tbh the Samyang 135mm f2 is also excellent (at least the sample I had!)

[@antoniohuerta9144]

If you do not care about the star shapes, then Samyang 85mm F1.4 would be even better (and cheaper) ! I mean 1.4 is better than 2.0.

[@AstroQuest1]

Nice comparison Cuiv. I use both as well - I guess I don't care about star shapes. It comes down to what you have and what you are comfortable with. I can't believe how many videos you make - certainly not Lazy. Work just started up again so I have very little time for videos and processing right now. - Cheers Kurt

[@CuivTheLazyGeek]

Thanks Kurt! Yeah making the videos and editing them is a lot of work - I usually make a bunch on Sunday, so that I can edit them and release them over time... I'm selectively lazy :D And YES, not caring about star shapes is the way to go!

[@mehdiabed6942]

lens require very specific focusing routine .( ie : do not focus on center nor by HFR calculation on the whole image. Each lens has its own area for focusing . it is like a signature and you have to found it by testing .) . It seems that the best lens so far is the Sigma ART 135 mm ( same behavior as a astronomical refractor) . clear sky .

[@CuivTheLazyGeek]

Thanks for pointing that out Mehdi! In general, a square doughnut can be used to do HFR calculation (e.g. use stars that are between 1/3rd and 2/3rd of the way from the center), and it works quite well then. This is possible in NINA :D As for the Sigma ART 135mm, it is indeed very good, but I did find the Samyang / Rokinon provided slightly better star shapes with better controlled chromatic aberration. But it could simply have been my samples!

[@nikivan]

@@CuivTheLazyGeek What are the exact settings for this? I found the crop factors in NINA confusing. It is not clear to me if the value from zero to one represents the distance (or is it surface percentage?) from the center or the periphery of the frame. Also, some values are prohibited to enter. Thanks.

[@CuivTheLazyGeek]

@@nikivan it's a distance ratio from 0 to 1. It's explained in details in the NINA documentation here! nighttime-imaging.eu/docs/master/site/advanced/autofocus/

[@TeodorAngelov]

I love it everytime he goes out of his way to say he's in Tokyo. The roof aesthetic is awesome there.

[@CuivTheLazyGeek]

Thank you :D

[@TheFlyingScotsmanTV]

I did exactly that. Got a 2nd hand 300mm F4 L non IS off ebay (came from Japan!). 350 pounds. Much less than an equivalent 2nd hand refractor and field flattener. I've not used in anger much yet, but glad I'm not the only one that figured that was better value for money for what I need. There is quite a lot of 'you can't possibly take pictures of X without ' on the forums and it's easy to get dejected or sucked in. As you say, I doubt it helps their happiness - enjoy what you see and don't sweat little details!

[@JohnDoe-tm1rv]

Now it is not so easy to find 300mm F4 at a good price.

[@astrodysseus]

I love your channel, it's funny how we kind of do similar tests although I never had time to create a blog (albeit a few friends insisting !). Anyhow when I saw the title, I nearly took popcorn as it's indeed a long lasting discussion; I even had that discussion with some astronomy clubs and the general agreement is: yeah telescopes are slightly better. So I agree with your message that camera lenses are still fantastic and for any beginner or hiker, that's definitely a great/better solution. The thing that I want to add though is.. are you familiar with MTF charts ? Different camera lenses have hugely different behaviors in terms of chromatic aberration and coma. So it's very difficult to generalize about camera lenses and star shapes. I love my Nikon 35mm f1.8, great color, great contrast but a lot of coma and I have to step it down to F4 so it's nice corner to corner. On the contrary, I also have the Nikon 300mm f2.8 AF-S, a gem in my opinion. It's old so this professional lens is now accessible (~$1000) and It also accepts 52mm filters (hence I love IDAS filters). The lens is much bigger than this canon, but the quality is impeccable across the frame, even at f2.8. At f4 I personally don't see any difference with a telescope and I usually only stop down the lens to show off the sharpness or when using a teleconverter as otherwise coma is starting to show. Speaking of coma, if you don't use a field flattener with a telescope, coma will actually be worse than with camera lenses, it's really terrible, so one more piece of equipment when using a scope. Lastly: triplets. I really love my nikon lens and I tested it side by side with both a triplet 80mm and triplet 102mm. The one thing that I can say is that the difference was not in coma/star shape but more in terms of contrasts and how the colors bumped out on raw images. A triplet is really extraordinary for the rendering of colors and I do believe that no camera lens can perform as good. However with a bit of post processing and play with vibrance/saturation etc, the end results are very close. So once again, yep telescopes (with field flattener) are slightly better than camera lenses but not by far.. and it really depends on which camera lens. Also if you want more than 600mm, you will have to use a scope and probably more a SCT rather than a refractor. Seems like I still need popcorn for that discussion - cheers (ps: I am French too :) ).

[@CuivTheLazyGeek]

Laurent-Philippe, thanks for the feedback! And yes, it is a vast subject, and that's why I effectively cheated by comparing a single lens (although a well-reputed one) without going too deep into all the rest, as that lens presents fairly characteristic results of what issues you can have. I am of course familiar with MTF charts, but yeah, preferred not to get into that today! The Nikon and Canon 300mm f2.8 lenses are amazing, although my 20+ years old sample of the Canon lens had that "haircut" wide open on the stars at f2.8... there is so much variability between lenses, even of the same make and model, it's almost like mounts in astrophotography! You make a very good point on the color rendition - I agree with you on that, but it's very hard to show the difference unless you manage the same skies and same focal length and same SNR... For more than 600mm I'm Newtonian all the way! But for 1000mm+ yeah SCT or RC or VMC or VC becomes unavoidable... So many French people watching this channel - c'est assez genial... je suis desole que tout soit en anglais (je ne connais meme pas le vocabulaire necessaire a l'astrophoto en francais!)

[@MetaView7]

That's a very good comparison. Thank you. I was going to buy a Samyang 135. I guess I should reconsider.

[@CuivTheLazyGeek]

That Samyang, if you get a good sample, can be an absolute beast. Even if the star shapes aren't perfect, being able to image at F2 is really nice!

[@BrokenPik]

what filter were you using in front of the 533 for the viel ? (Optolong L-Extreme ) lol hey Mitch finish watching the video before asking questions !!! great shot...

[@CuivTheLazyGeek]

There you go :D

[@spordniar]

Nice video, I wonder if you can do a comparison between a Newtonian vs Refractor of the same price range, and see if one of the resulting image is superior than the other.

[@RaysAstrophotography]

Good to know about this Cuiv!

[@CuivTheLazyGeek]

Thanks Ray! It's always fun to be comparing equipment like that - and lenses can be quite powerful overall!

[@joseribeiro9564]

I have made a custom dovetail with adapted fixing ring from my first newtonian telescope, for a Canon 500mm f4 mark i, the brightest stars do suffer from halos when used with LP filters, besides that the shape of the stars till the corners are spotless if i focus correctly, still on the fense considering the best upgrade route to that kit..

[@CuivTheLazyGeek]

If it works well for you, maybe no need to upgrade? :D

[@joseribeiro9564]

@@CuivTheLazyGeek thank you for the reply, the upgrade would be to gain some more aperture and focal length to expand a bit my doable targets, those cute little galaxyes still evade most of the pixels of my camera, a centralDS 60D cooled camera, should a small sensor from a dedicated astro camera be a sensible choice to fill more the frame?

[@ivanhancock]

Hey Cuiv, Great Video's, Could you please do a video explaining the working out of Gain & Offset with OSC Cameras, and also dithering settings to eliminate walking noise. These to subjects are giving me grief with my final images, Many thanks, Keep up the great work !!

[@CuivTheLazyGeek]

For the gain and offset, all the information needed is here: kzbin.info/www/bejne/iYq0YpxqoJtlm6s ! For dithering, I could make a video on that, but the gist of it is you want to set up the dithering large enough that you actually see the stars move from frame to frame on your main rig... Good luck & clear skies!

[@xe1zlgg]

You should match the SNR on both refractive systems ( that will rise the contrast on the Canon Lens image ), also Canon L lenses are not trully apochromatic... you should try a Zeiss Apo sonnar desing against the little Sharpstar , otherwise image will be a lot better on the telescope... thanks for share.

[@CuivTheLazyGeek]

Thanks for the feedback Luis! You are right on the SNR, but then for star shapes comparison it doesn't really matter that much... I wish I had a Zeiss APO Sonnar design to test with!!

[@xe1zlgg]

Hi Cuiv.... maybe a Zeiss seller would ve happy to send a Zeiss 135 Milvus ( same desing as the 135 Apo sonnar ) for review.... that would be very exciting ! CS. LUIS

[@CuivTheLazyGeek]

@@xe1zlgg That would be super cool! I'll probably need more subs first, for a seller to ship to Japan :D Japan resellers wouldn't be interested in an English-spoken channel... Cheers & clear skies!

[@cmeluzzi]

Great video and honest analysis, thank you! When I shoot with Canon camera and lenses I usually open the RAW files in Canon's DPP4 software. It applies lens correction algorithms to the image thus minimising the weird effects on star shapes causes by lens imperfections. Then I convert the RAW into TIFF to be stacked and further processed in other software. It is not a complete solution but it seems to help. Have you done that before?

[@CuivTheLazyGeek]

Never done that! Good idea though...

[@komr323]

I have just checked out the dpp4 function it’s just like the Lightroom. May I ask have you try to correct the image after the photo is being stacked? And what’s the difference?

[@cmeluzzi]

@@komr323 I haven't done a scientific testing, but I suppose that if you stack better quality subs, the final stack tends to be better. As a general rule in photography (not only astro), the better source you have, the less you work in post. Every time you edit something in post you add side effects to the picture that you might further correct and so on, thus diminishing the overall image quality. I think that DPP4 has the right algorighms to counter Canon lenses' artifacts, as they are produced by the same company. I'm not sure if Lightroom algorithms are the same, worst or even better for Canon lenses. Anyway, if Lightroom is doing a good job for your images, that would be better for your processing too, I think.

[@JamesPetruzzi_MyHawaiianImages]

I use my 533 with a 100-400 f/4.5-5.6L Canon lens and with the small chip on the 533 in that big full frame image circle, I have zero problems at the corners because the corners of the sensor are still in the center of the image circle. Of course, that lens costs 3x what the Sharpstar costs, but then I already had it when I took up astrophotography. :) But as far as star sharpness goes, at 300mm the Canon is off the charts. So it might depend on quality of the lens as well.

[@CuivTheLazyGeek]

That sounds like a sweet lens! Do you use it wide open? Lenses are great starting points for anyone who came to the hobby while already being into photography :-)

[@JamesPetruzzi_MyHawaiianImages]

@@CuivTheLazyGeek Yes, I just have the ZWO adapter so no aperture or focus control. I do use an IR cut filter w/it, which helps a lot as well. Rides piggyback on my Edge8HD. Really planning on going RASA 8" for wide field in future tho. :)

[@louisrosner7902]

Another great video. Can you just elucidate really more about your back focus. Exactly where are you measuring from. The back of the reducer glass or the edge of the reducer itself. And are you measuring exactly to the sensor in the camera. Thanks again and keep the videos coming. I love my Sharpstar 61 also but had to use an improvised dovetail bar So that I could achieve Dec Balance.

[@CuivTheLazyGeek]

Thanks for the feedback Louis! Backfocus is typically the distance between the shoulder of the reducer (e.g. the base of the M42 or M48 threads) and the sensor in the camera itself. I have a whole video about it here: kzbin.info/www/bejne/gqS3aoSXhLOHrNE Clear Skies!

[@GrowingAnswers]

I am surprised there is that level of noise with a cooled camera and stacking. Is that the zwo with the apsc sensor?

[@CuivTheLazyGeek]

This is with the 1 inch sensor of the 533MC Pro - That amount of noise is perfectly normal for only 39 minutes on one target. There is a high amount of shot noise from the target, and read noise might actually not be fully overwhelmed in the lower nebulosity areas of the capture...

[@juangh85]

I recently bought a 75 - 300. Waiting for the possibility of an EQ Goto mount. ;)

[@CuivTheLazyGeek]

Oh it would be so neat to see how well that lens works!!

[@kenkoskela3357]

Thanks very much for your videos, which are great. I have a question on camera lens vs refractor that relates to back focus (focal flange length). I purchased a new ZWO mono camera that has 17.5mm between sensor and the edge of the camera (the 2600mm). The filter wheel is 20mm thick. Canon EF lenses require 44mm of back focus, which I understand is less than [most?] telescopes that [typically?] have 55mm of back focus. After the camera and filter wheel combined, I have only 6.5mm until I hit 44mm of back focus. The 6.5mm would not be enough for an adapter that connects to a Canon lens. So, with this new mono camera, am I correct that shooting with a Canon lens is not even an option? Or, is there some workaround that I am unaware of? Thanks for any insights on this.

[@davidaylsworth8964]

Interesting video. I’ve recently been using my 70-200mm f/2.8 for wide field astrophotography. I’ve been using it wide open though. Guess I’ll have to see about stopping it down to f/4.

[@CuivTheLazyGeek]

You should see a big difference in star sharpness!

[@nerys71]

What about a Reflector Camera lens? I have an 800mm reflector lens for my Canon.

[@MethiasZa]

Just come back from a dark sky site and had my scope collimated. Not completely perfect at the edges but so close where I dont care. And I wasnt happy with my guiding, but for some reason I managed to get round enough stars where I wonder if I should care bout it. It seemed to behave well enough that things looked fine in 10 min subs. Sometimes I think we worry about things we shouldnt :)

[@CuivTheLazyGeek]

Exactly - it's important to have fun, especially when talking about data from a dark site! I hope you got some great results!

[@MethiasZa]

@@CuivTheLazyGeek Well its a sad story, 1st night got around 6hrs of data at 4am the HDD crashed the files were being saved to. RIP night one.

[@CuivTheLazyGeek]

@@MethiasZa Oh nooooo! Nothing recoverable on that poor HDD?? F for respects...

[@MethiasZa]

@@CuivTheLazyGeek Im trying to run some recovery software on it so I'll see

[@scarpography]

Nice comparison but I think there's one thing that makes the lens seem worse than it is... I have this exact lens and whenever you stop it down from the front, bright stars tend to manifest a lot of halos, plus you were using a duo narrowband filter, better to leave the lens wide open at 2.8 and enjoy those pin point stars

[@CuivTheLazyGeek]

Very interesting - I had worse results wide open with my sample... I may do some further tests, thanks for the suggestion!

[@tycho_escher]

Nice comparison, thanks. How do you know how many step down rings are required to get your lens to f4?

[@michaels3003]

There is nothing magical about f/4. It is best to test and experiment. Reducing the effective diameter of the objective lens by 25% should be an equivalent of one f/stop (50% reduction of the captured light).

[@tycho_escher]

Michael S thanks

[@CuivTheLazyGeek]

In addition to what Michael said (which is absolutely true), each step down ring tells you its internal diameter (written on it) - so simply take the focal length of your lens, and divide it by the ring internal diameter to get the new focal ratio!

[@tycho_escher]

Cuiv, thanks

[@renegossel5139]

I have the Same 200mm Lens. Did your shot at f2.8 of you Close the aperatur?

[@georgehatfield9473]

Excellent! Learned a lot.

[@CuivTheLazyGeek]

Glad it was helpful!

[@stephen2615]

Star shapes. Phfft, ignore the soon to be trolls. Getting satisfaction from your own pics, priceless. Did you ever do a NINA polar alignment video?

[@CuivTheLazyGeek]

Exactly :) Yes, it's here: kzbin.info/www/bejne/gpaYc32Zd6Z3d5o

Thanks for the vidéo bro, clever and usefull as usual.

[@CuivTheLazyGeek]

Thanks Romain, glad you enjoyed it! :)

[@TomBridle]

I am also far too lazy to stop down for stars haha. I rarely get clear skies so imaging 400mm at f/2.8 is pretty awesome, I just can't get enough of that sweet sweet light.

[@XTurionX]

What do you think is a better option Rokinon 135 mm f 2.0 vs new Raptor 61 ??? Thx !!!

[@edwinsanchez1167]

Hi Cuiv!! I got a zwo T2 adaptor to use my sigma 70-300 apo camera lens BUT I dont get how to change f stops, on my dslr its easy you just change it but on my asi 183, how do I? Thanks and clear skies!!

[@MethiasZa]

Oh I do have one question to ask, could you please do a comparison between a one shot colour astro cooled camera and a DSLR on the same target, same mount, some scope/lens if possible? I'm always curious as to how much a difference one can see by upgrading from a DSLR to a OSC Astro camera

[@CuivTheLazyGeek]

Well, I just (finally) got a DSLR so it is doable indeed - thanks for the idea! But then my DSLR is non-modified... Still, it should give a good idea on non-HA rich targets :)

[@MethiasZa]

@@CuivTheLazyGeek Thanks, I have a DSLR (I did astro mod it myself in a fit of insanity) and I'm really curious as to the differences or if Im simply needing better filters and more time on targets

[@CuivTheLazyGeek]

@@MethiasZa Sounds good! I've modified several Canon cameras, and that was quite straightforward, but my Pentax has IBIS (that can actually be used as an in-camera star tracker), so I've unwilling to do the mod on it...

[@MethiasZa]

@@CuivTheLazyGeek Oh ye fully understand that. I cant mod my normal camera I use daily, so I got myself a cheap Canon 550D. Old now but it works well enough for me to get images. I know people say a dedicate astro cam works better (I would imagine it would) but im curious as to how much better, is it a massive leap or is it like this lens and scope, sure its better but it still produces images that are pretty close (and is significantly cheaper)

[@CuivTheLazyGeek]

@@MethiasZa Sounds good! Spoiler alert: with a cooled astro-camera, the difference is massive, both in case of raw image quality (far, far less noise in each image, and so more nebulosity is visible as it is above the noise threshold), and easy to take calibration frames (take darks and flat darks at any time you want, you can even make a library, since you can control the temperature) - because you have better matching calibration frames, that translates to even better SNR overall. It's a whole virtuous flow. I have tested by forgetting to turn my camera cooler on at a dark(er) site. It basically made the whole trip useless... I'll make sure to have a video on that though :D

[@stephane153]

Thank you Yannick for this video, much appreciated.

[@CuivTheLazyGeek]

No worries! Glad it was helpful :)

[@stephane153]

@@CuivTheLazyGeek It was, in the end I will be going for the 61EDPH instead of a lens.

[@DrGkill777]

There is a mistake. When you close your lens to F/4 you decrease the effective front diameter light collection. So It's normal that you obtain lower SNR than with the 61EDPH. Lens has only the advantage of giving a wider field. After all the light gathered is only a question of overall effective diameter of the telescope. The issue with fast lens is that you are dramatically undersampled. A samyang 135 f/2 will be about 1.5" theorical resolution but even with a small photosite camera (3.8um) you will be on 5.7"/pix. So hugely undersampled.

[@mackiemesser9304]

Hey Quiv! What kind of holder do you use to mount you astrocamera + canon lens on the mount. This silvery one? Ty!

[@CuivTheLazyGeek]

This one! www.electricsheep.co.jp/astroshop/?itemcode=esring01

[@lazareftd]

Just Bought a sharpstar 61edph yersteday ! :)

[@CuivTheLazyGeek]

Woohoo! I hope you'll like it! I am really enjoying mine a lot :)

[@michaelmistaken2863]

My SharpStar 76EDPH arrived from Teleskop Direct and I’ve been doing some daytime/indoors setup to get used to it, my camera, and the mount. Thanks for the wise videos, Cuiv!

[@alesizzz1]

Excellent !!!

[@BennyKleykens]

Don't care about star shapes either, after all it's mostly pictures I show my wife and child. However, I feel you did not make it clear what the cost of your rig is (tripod, tracker, etc) as those are obviously required to make the shot.

[@johnybaby2]

Fuck the star shapes lol. Have you tried adding sulphur ii data to the oii and Ha data you get from the l-extreme?

[@kk-px7lu]

I use camera lenses, ye crap pics but I still enjoy it.

[@o0L4nc3r0o]

It also depends on how wealthy you are. :) When you're also a regular photographer, but you don't have unlimited funds, you're probably better off getting a decent multi purpose lens though.

[@CuivTheLazyGeek]

That's pretty much it :)

[@toddnoseworthy1447]

Did you calibration frames for both?

[@CuivTheLazyGeek]

I believe I did, yes

[@danieltaormina1472]

Camera is still very good

[@juangh85]

First like!, First comment!

[@CuivTheLazyGeek]

Well done, and thanks for both!!

[@wrnchhead76]

Star shapes, exhausting. I think it's fine for a person to want to improve their images, but getting wildly out of shape over them is no fun for anyone.

[@CuivTheLazyGeek]

I am with you there - at the same time, I understand how many can take a huge amount of pleasure and satisfaction in achieving pinpoint star after getting the right equipment, and fixing all sorts of issues with tilt and backspacing! I am less happy when star shapes are being criticized for the sake of criticism, when things get a bit snobby...

[@xthespinne5985]

This is a bad example for a lens. There are some apochromatic lenses from sigma and they are very good for ap

[@CuivTheLazyGeek]

Still one of the most popular and affordable lenses used for astrophotography ( (+ works with Astromechanics for autofocus), so while it may not be the best lens around, I hardly think it would be a bad example.

[@xthespinne5985]

@@CuivTheLazyGeek I mean yes but comparing it to a apo is still kinda unfai5