Why CROP FACTOR Scares Astrophotographers - Understanding Image Scale

[@trulsdirio]

I love how we named 35mm film as "Kleinbild" here in Germany, as that translates to "small image". So for film this was already the smallest viable format, followed by medium format and large format (such as 4x5 and 8x10 inch negatives). Digital sensors just have so much more resolving power that the smallest viable film format has become the bigger of the common digital formats.

[@sonofoneintheuniverse]

Hooooray - this video is spot on (unlike most other crop factor videos). 😊

[@barbaraharris6102]

Great job of explaining those concepts.

[@bobair2]

I only use full frame sensor cameras and use the glass to create "crop ins" as a smaller sensor doesn,t magically make a lense longer for an equivalent crop. Full frame sensors for a given number of megapixels are less noisy and have better dynamic range and give a wider field of view.

[@Christiaan-qj8fi]

Great video! It’s always tough when I have to describe to non astro people how we think about detail, now I’ll just send them this!

[@AlaskanAstro]

Excellent! Exactly what I was hoping for in making this one.

[@AstraPharmaq8]

Your effort on this video definitely paid off 🤝🏼

[@AstroQuest1]

Excellent video explaining the differences. I was always wondering why they use this distinction with DSLRs rather than just talk abouth the camera sensor size and pixel size at least for Astrophotgraphy. Cheers

[@Xingchen_Yan]

Bro I love this video, you did a phenomenal explanation. Cheers!

[@587583922]

I'm glad SOMEBODY understands this. I've been arguing about this with yoututbe-"trained" photographers for years in other contexts. No one gets it. Focal length is focal length no matter the sensor/film size. There is no "equivalent". Outside of astrophotography, it seems like no one gets this...and the only explanation I can come up with is that none of them have ever looked at an image closely enough to see perspective.

[@ronlundgren4391]

Great breakdown of this topic. Thank you.🍻

[@frankm81m82]

One other caveat is that full frame sensors give a wide FOV but require a lens or telescope that can create an image circle that would cover the whole chip and produce acceptable image across the full chips FOV, full frame requires better and likely more expensive lenses and telescopes

[@s.l.3918]

don't forget all those filters xD

[@ADifficultQuest]

Great video! awesome explanation!

[@dumpydalekobservatory]

Watching this has confirmed my reasoning for not bothering to buy a 533 camera as I already have an APSC with the same size pixels so I really can't see the point in owning one of those square sensor cameras as I can always crop into the image & not lose any resolution. I'm not saying the 533 is a bad camera but I'd say hold out until you can afford one with the APSC sensor as it gives you far more to use regarding field of view etc.

[@00_Ryan_00]

this video was too smart for my wide angle nightscape needs. LOL

[@coin777]

If thats true. Why Everyone doesnt do astrophotoghraphy with smartphones with 100 megapixel tiny sensors

[@AlaskanAstro]

This is a whole other topic to talk about that can be summarized as: how much light does each pixel catch? You can look up the ideas of etendue, per-pixel SNR, and shot noise.

[@dogghedman]

GREAT Explanation 👍🏾👍🏾👍🏾

[@12symmo]

You forget, lenses do actually become longer when they’re attached to Olympus cameras, their users say so. But the aperture doesn’t change. /sarc

[@Aqua2D]

i wanna make sure im understanding your point; are you saying that, for most general photography, crop factor is a useful measurement, especially when megapixels stay the same between sensor size. but, with astrophotography, its much more useful to use image scale.

[@AlaskanAstro]

I would say ONLY if megapixels stay exactly the same is crop factor relevant. Unless you just don't care at all about detail and are only comparing the fov between a FF and crop sensor camera.

[@Aqua2D]

@@AlaskanAstro thank you for the clarification. i can totally see how, for astrophotography, crop factor is a silly term. in almost every other situation for my photography, i dont care enough about fine detail to worry about image scale, and i find crop factor to be a very helpful term.

[@Zehrapodcast]

what camera you used to record yourself?

[@AlaskanAstro]

Canon R8 and EF 50mm f/1.4

[@wadwadwadwadwadwadw]

okay, but having the same crop fa... I mean image scale but different pixel sizes does have an effect on image quality as it effects the noise level (in a rather complex way). That could be also something to consider and deep sky might have different optimum than planets

[@AlaskanAstro]

Yep that's a whole thing that I didn't have time to get into in this video. Maybe a subject for another video. (Probably not 😄)

[@sonofoneintheuniverse]

Modern CMOS image sensors have gapless microlenses and noise differences between different pixel size sensors are negible. This was different in the days of CCD sensors whan fill factor was an issue. Modern sensors and old myths...

[@nordic5490]

​@@sonofoneintheuniversebigger pixels = more photons per pixel = better signal to noise. Eg, a 45Mpix ff sensor does look much noiser than a larger pixel 25Mpix ff sensor at the same iso. This is very easy to demonstrate.

[@wadwadwadwadwadwadw]

@@sonofoneintheuniverse So you suggest a smaller microlens collects the same amount of light as a bigger one... I would advise you to get informed at least about the basic physics of light detection before making such comments. An additional hint: shot noise is just one source of noise, and not always the most significant.

[@TishaVanDiest]

Well done

[@Psychlist1972]

14:40 that mosquito has you marked. crop factor or not :)

[@Psychlist1972]

18:12 I think she got you.

[@CaptRescue2]

learned...thanks

[@thdbird83]

"crop factor" it is just a change of field of view. there's no magical zoom/magnification benifits if it is slapped on a APSC / M43 sensor. 50mm lens will always be 50mm lens. a 300mm lens is still a 300mm lens.

[@johnanthonycolley3803]

please excuse the Portrait Photographer. being primarily captivated by faces But I couldn't help but notice, in the final screen. that you appear to have been getten bitten by a Mossy on the forehead ..

[@AlaskanAstro]

I should post a video of how bad they get. This was nothing.

[@Scotian280]

Place your bets here on if he had 2 big mosquito bites later on his forehead :-P

[@samsmith1580]

Beard much.