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muletopia
16-04-2019, 05:25 PM
From a Canon EOS 60Da I have a series of 2X2 binned pictures and a series of 4 times longer exposure unbinned.
The unbinned images are black and white so the following steps were taken with Nebulosity 3.
The unbinned photos converted to colour, the Binned photos resized by a factor of 2.
The images from both sources were stacked and the stack digitally developed and adjusted with curves.


The result is nicely sharp but is still black and white (the binned stack has colour).

Both series had appropriate darks subtracted before manipulation.


Can someone tell me what I am doing wrong or what additional steps are required please?


Chris

leon
16-04-2019, 07:33 PM
Chris with all the bnning :shrug: stuff, what are your actually talking about :shrug:
Irreverent to the Camera and you have a Canon, just take the pictures a short/long as you like and stack them.

What the hell is binning, although i don't do it now imaging was easy and it did not involve BINNING :shrug:

Man In took some fantastic wide fields and BINNING was a silly word

Leon :thumbsup:

sheeny
16-04-2019, 09:16 PM
Leon,


Binning is the process of reducing resolution by combining pixels in order to gain sensitivity. 2x2 binning means 2 horizontal pixels and 2 vertical pixels are combined so that the binned pixel is 4 times as large and therefore 4x as sensitive.


Typically colour channels are collected binned and the luminance channel is collected unbinned (for maximum resolution). The colour channels are recombined in LRGB processing to construct the final image.


Sorry Chris I can't help directly with your question as I'm not familiar with Nebulosity, but it sounds like the binned colour channel images are simply being stacked with the luminosity channel rather than being applied to the LRGB channels.


Al.

xelasnave
17-04-2019, 09:46 AM
I wanted to ask about binning and thought to open a thread but it looks as this is a great place to ask...with my set up..80mm f5 refractor and zwo 1600 and using startools what binning shouls I select.
Startools offer 25% to 71% I have been using 71% only the basis I want the biggest☺ but lately have been using 50%...I dont know what I am doing or why but at least happy to own up to that flaw.
Hopefully an educational discussion will unfold and folk like me will learn more.

And I think from memory you can bin in sharp cap ??? If that is fact what guide lines should one follow there?
Alex

xelasnave
17-04-2019, 09:48 AM
You have not lived until you have experienced BINNING ☺
alex

sil
17-04-2019, 09:31 PM
debayering?

muletopia
17-04-2019, 09:47 PM
I have never had to de-bayer fit images using Nebulosity for camera control so I think that de-bayering is unlikely to be the problem.
Chris

luka
17-04-2019, 10:54 PM
Chris, I am not sure I understand correctly.
AFAIK Canon EOS 60Da does not have hardware binning. So, if you do 2x2 binning in software (Nebulosity?) and then resize by a factor of 2 (to increase resolution) you will be back where you started... with probably some data loss.
(Also if Nebulosity is doing the 2x2 binning then it must do deBayering before the binning or the colour information will be lost - probably not a problem as you mentioned that the binned stack has colour).

Few suggestions:
Can you check your final images just before stacking, do they have colour. Pick a single binned image and a single unbinned image.
Then separately stack binned and unbinned and see if you get colour for each stack.

luka
17-04-2019, 11:21 PM
Alex, StarTools allows you to use "software binning" to "add" adjacent pixels and increase signal at the expense of resolution. 71% will give you stronger signal but smaller final image. You have to decide what you want, sometimes you may want a larger image (to see more details for example) but sometimes you may want to amplify the weak signal more (smaller image).

Now someone correct me if I am wrong here. ASI1600 does not have hardware binning so SharpCap will "add" adjacent pixels to improve signal at the expense of the resolution. This is useful for finding weak targets in the sky or for guiding. However, the binning can easily be done at the image processing stage with identical results. So there is not much point of acquiring images with binning with ASI1600. Having said that binning at the acquisition stage will result in smaller images that require less resources for storing and processing.

As a note, some sensors (CCDs mainly) offer true hardware binning where signal from 4 adjacent pixels (for 2x2 binning) is added on the sensor itself before being read. The main advantage of doing this is that only one read is required for the "combined pixel" as opposed to doing 4 reads (one for each of the 4 pixels) and then binning in the software.

Effectively hardware binning on the sensor would result in 1/4 of the read noise compared to software binning on the PC (1/4 in theory, in practice it is not that effective of course).

Also worth emphasizing is that the read noise on the modern CMOS cameras is very low (ASI1600 for example) so that the hardware binning would not offer much improvement over the software binning.

Hope this clarifies few things about binning.

Startrek
18-04-2019, 12:35 AM
Refer my post in “Beginners Talk” regarding basic information on Startools Binning

xelasnave
18-04-2019, 05:22 AM
Thanks for an excellent post Luka.
Alex

sil
18-04-2019, 10:08 AM
its not needed for camera control and its why you are getting mono images..because you are NOT debayering. google it. by binning you are basically debayering but not properly. debayering is your problem, well lack of understanding really. dslr you must debayer at the right point in the workflow.

muletopia
18-04-2019, 07:49 PM
Sil,
You are spot on, my lack of understanding was/is the problem. With debayering I now have colour pictures.


Thanks all


Chris