Astro-Camera and Binning: What does it do? And how does it work? 

Hello Cuiv! Good explanation regarding the read noise aspect of binning. However, the advantage of CCD over CMOS vanishes in situations where thermal noise or light pollution becomes the dominant noise source -- such as when taking longer exposures or when in light polluted areas (light pollution obeys the same rules as thermal noise in this particular respect [although without being a function of temperature, of course]). In other words, when exposing long enough such that the read noise becomes negligible compared to other noise sources, the signal strength is scaled by the number of pixels in the binning, and the noise [standard deviation of the noise] is scaled by the square root of the number of pixels in the binning; and that's the same for both CCD and CMOS. -- I love your videos by the way! :)

I don't mind telling you that, when I finished watching this video, my brain was full.

Thanks, really enjoyed that content. Really clearly explained and helpful. There's so much to learn for astrophotography!

Very helpful. I never really understood binning. After watching your video, I have a better understanding.

Great videos Cuiv. Some of the most informative out there. You keep the information flow well organized and content just detailed enough to get us started. Thanks for the links too!

This is the best explanation of this I've found.

After at list 5 videos, now I can realize the binning of the smartphone camera. Thanks a lot :)

Thank you, thank you, thank you. As a newbie I, like you formerly, have watched many videos where authors have mentioned binning but never explained what it was and why, or why not, they adjusted it. Add to that the fact that the manual for my controller (ASIAir +) has not been released by ZWO so I've been referring to the ASIAir Pro manual which does not even discuss binning. This video really helped.

Nice explanation on binning! Thanks for sharing your expertise Cuiv!

Thanks! I now understand binning in CMOS OSC, which is my current application. I have successfully used 2x2 binning in this application and liked the result, but now that I understand the obvious downside with the RGGB layout of OSC, I'm likely to reconsider.

Thanks for the detailed explanation. My take away is simply this; why bin during capture when it can be done in Post. Binning will reduce the amount of data flow over a slow USB cable which is good but when saving directly to a NVMe SSD it makes sense to grab pure RAW data and play with Binning in Post Processing. I always want maximum resolution.

Amazing video explanation.

Cuiv, you do explain things very well. I have recently purchased a Starlight Xpress CCD 694H camera (which has large pixels) so that I could do ‘proper’ analogue binning on my EdgeHD 9.25” as it is oversampled even with a focal reducer. The 2x2 binned images are very good, though even the un-binned subs are very good. I think the long focal length helps with reducing background glow which also helps with unwanted noise. What I had not appreciated was that I can get a 2x noise reduction even with my ZWO ASI1600MM Pro, which is another camera I love. I think I will try my ZWO on my next project on the EdgeHD. Thanks again for that little snippet of information.

Very interesting video. Thank you!

Thanks for explaining binning.

Thanks, that was helpful!

OK, i am a bit of a newby, and all this math and theory, explanations...is great, BUT it also would be nice to give some short, practical information. this might show examples of an image taken with binning 4x4 vs 2x2 vs 1x1, what's the difference? can you see the difference, or only in a full resolution photo, vs internet shot? what is the practical way to set up for shooting a nebula or galaxy ....what will change based on your Bortle situation?...but maybe this is too basic info i should already know???, thanks for all your work! and your passion!

Thanks for the video. One thing you don’t mention is what advantages or disadvantages there are to binning with a guide camera. Would love to hear your thoughts on this?

Hi, your videos helped me alot. Regarding binning, how does it help in terms of amount of subs needed and or exposure time. ie. Do I need less exposure or less total subs when binning?

If you bin during post, how do you deal with oversampling? Don’t some camera/scope combos require software binning or tracking errors will happen?

Hello. So if I am oversampling by just a little, I should be OK? My setup is Edge HD 14" with .7X focal reducer and ZWO 2400MC with 5.94 pixel size. Thank you for confirmation of this and any ideas for more efficient processing in APP and PI.

On my SX694 mono I'll sometimes do 2x2 binning of my RGB but do Lum in 1x1 as resolution is more important in the detail layer.

So if i use any software(like Adobe Photoshop) to undersample the image captured bu my CMOS sensor, it will bin it. I have 2 main questions here. Would it also work for the CMOS sensor on my phone and will it only work for the raw files. Because undersampling 12 mp jpeg from imx 586 on Adobe Photoshop doesn't made a difference

Thanks Cuiv, I was wondering what the heck is binning. Now, I'd also like to know what is HFR, how can we read, interprete it, finally how and where can we use HFR values.

Hi Cuiv, Does binning affect the unity gain ? ( the graph companies provide in their websites) . I have QHY600M. Do you think it will be wise to use 2X2 ? thank you.

Great videos! I've learned a lot from you in the last three months since starting in AP. I have a 10" Newt with an Coma corrector and OAG/ASI220MM Mini. Could binning help the guide camera? It does seem to pick up a lot of noise for some reason. Not sure if it's the CC or not. Using NINA/PHD2. Thanks!

Hey Cuiv, great video! You mentioned no binning on CMOS ZWO cameras. However, you mentioned if you have a CCD camera undersampled you would. What if you are undersampled with a CMOS camera, would you recommend binning in-camera at that point, or still bin in post-processing with PI? In my current setup, I am oversampled so I am dithering and also drizzling in PI however I am looking at the ASI183MM (going mono) and a new scope that will cause my setup to be undersampled but a 2x2 bin will resolve it to a 1.1-pixel resolution. Appreciate any feedback!

Without the .7 reducer on my 8" CST, I use binning, because I get still more data than resolution + 4 times the amount of light on deeper wells that sums up to shifting thr F10 to F5 so I can take shorter exposures to mitigate bad data....

Do you know any free binning software for windows?

Great video! One question though, you mentioned using software after the fact to bin. However, I'm having trouble finding software that does true binning especially for a batch of files. Reading the PixInsight forums, it seems like it doesn't do real binning but instead does some sort of interpolation which will not have the same effect. Can you recommend some software for binning a set of subs? I'd like to experiment with some existing subs and see if it has any positive effect without potentially wasting a night of imaging and finding out it makes no difference.

Why not bin when you are not properly sampled? Consider a pixel that is 3.76u in an f/10 OTA. Would it be smarter to bin 2X2 or even better; 3X3 for such a situation? Thanks!

binning 3 of thumbs up 👍👍👍👍👍👍👍👍👍👍👍👍 = 1 big 👍

Hi, Can I use binning somehow on my smartphone camera? It has a 20 megapixel image sensor. I will be ok with 5 megapixels but with better dynamic range and quality. Thanks

I only use binning, when focusing with a bahtinov mask, to get a bigger Star.

You say you would not bin in camera. But in DSO, isn’t it true that under and over sampling based on your focal length and pixel size in microns comes into play. In my case for example, I cannot get any more detail from Bin 1 vs Bin 2 because at 2855mm fl and a pixel size of 3.76, one pixel is .27 arc-seconds and I’m never going to get that kind of resolution on any seeing day. With 2 arc-second seeing, I’m still dropping a theoretical best results on star over 7 pixels. If I understand well, that’s just practical physics and so moving all that data for 7 pixels isn’t gaining me anything, and going to 2x2 binning I’m not losing any detail from my optical system. In fact considering that my site probably is more often at 3 arc-second seeing, even with my 0.62x reducer, which I always use in the train, the math still favors 2x2 binning. And as side benefits, the files are much smaller and I utilize lucky imaging for DSOs, going with 10 second subs and aiming for at least 200-250 subs in a session. But am I understanding well what is at play? I’ve convinced myself that in my system 2x2 is not a compromise. It is the correct number of pixels being used to correctly sample an ideal star point on my sensor with my optical train. Thoughts?

Ok, this will take awhile for me to understand, but if I did get this right, binning would have more of and advantage with a sensor with smaller pixels? or not

I suspect the CCD explanation is an over simplification. I understand because rows are read and sampled, then the next row, that binning to at least some extent is that only adjacent pixels in the same row can be read at the same time without adding to the read noise.

ok of all the videos ive seen.... noone says a word how.... more light ? its the same amount of protons hittin the chip... so how is there 4 times the light ?

Your illustration of 2x2 binning is actually of 4x4, no?

i thought i saw a shooting star 3 seconds past 12:12 turn out it was a bug

Not from 100 x 100 to 50 x 50, but rather, from 100 x 100 to 25 x 25

Cuiv, Irish?