How to Debayer

Hi Greg ( @gregwrca ),

If you supply raw images that have the correct information in their metadata, debayering is fully automatic in APP.

This will hold for Canon and Nikon camera's.

For Fits frames captured with a capture application like SGP, the metadata doesn't have the information needed to do it automatically. In that case, in 0) Raw/Fits , enable Force CFA. This will inform APP that the data is actual Bayer CFA data and should be processed as such 😉

In 0) RAW/FITS you can

• toggle between different debayer algorithms. By default, APP's unique Adaptive Airy Disc (AAD) is used.
• And you can choose the correct Bayer CFA pattern like RGGB., RGGB is the default pattern.

Let me know if you need more information 😉

Kind regards,

Mabula

Thanks much I'm using a Canon T3i so it sounds like I'm all set there in automatic mode.

Yes, indeed 😉

To The Group,

I am new to APP, and I'm in the 30 Day Trial period, but I am unclear if I need to do anything in the Raw / Fits tab during the file load phase.

I have a modified T2i canon and I capture all my lights, darks, flats and bias frames using the "custom WB" choice for the T2i. I created the custom WB by shooting a grey card during a clear day (at noon). When using Deep Sky Stacker, I load the files with the RAW setting set to "Use Came's White Balance" option selected.

Thus my question, how should I treat my files while loading into APP since I have a modified camera and not the stock T2i? After loading the files, APP does show a T2i is the camera used.

I hope my question makes sense, I appreciate all the help I can get.

If there is a forum that discusses modified cameras and APP please let me know and I'll research in more detail.

Thanks in advance,

CorralesRay - T2i modified, 85 and 135mm prime lenses, Sky-Watcher Star Adventurer mount.

Posted by: CorralesRay

To The Group,

I am new to APP, and I'm in the 30 Day Trial period, but I am unclear if I need to do anything in the Raw / Fits tab during the file load phase.

I have a modified T2i canon and I capture all my lights, darks, flats and bias frames using the "custom WB" choice for the T2i. I created the custom WB by shooting a grey card during a clear day (at noon). When using Deep Sky Stacker, I load the files with the RAW setting set to "Use Came's White Balance" option selected.

Thus my question, how should I treat my files while loading into APP since I have a modified camera and not the stock T2i? After loading the files, APP does show a T2i is the camera used.

I hope my question makes sense, I appreciate all the help I can get.

If there is a forum that discusses modified cameras and APP please let me know and I'll research in more detail.

Thanks in advance,

CorralesRay - T2i modified, 85 and 135mm prime lenses, Sky-Watcher Star Adventurer mount.

Hi @@corralesray,

Welcome to the APP forum and thank you for your question.

In APP you can do the same thing as you do in Deep Sky Stacker, in 0) RAW/FITS you can enable or disable the camera's white balance. If you enable it, it should apply your custom white balance on the linear raw data from your Canon T2i.

There is no rule on how you "should" process your images with your modified Canon T2i. I have both a modified and unmodified Nikon DSLR and in both cases I don't use the camera white balance. Color calibration normally is done after integration of all your frames and I think that you want to integrate the regular raw data without applying camera white balance. (If you do, you immediately throw away data on the right side of the histogram, because the multipliers for camera white balance are 1 or greater.)

In my experience, enabling camera white balance practically does not make a difference in the end result after star color calibration so I choose to not use it at all, to prevent earlier data clipping in the stars.

Your question relates to the fundamentals of how your camera works as well. Enabling/using  camera white balance  only really makes sense if the camera model specific color matrix is applied first to the linear data. At the moment, APP does not do this ( DSS is not doing this as well).

I soon will provide the option that you can load your raw linear data with the camera matrix applied and in that case, using camera white balance is preferred I think 😉 Applying the camera matrix on linear data and keeping it linear for further processing should be a great improvement so I will introduce this soon to APP. (I don't think other applications do this yet either).

Let me know if this answers your question and If you have more questions,

Kind regards,

Mabula

Mabula,

Thank you for the reply. Your response did answer my question, I have a lot to learn.

I am very impressed with this program, Thanks again.

Ray

@corralesray,

Excellent, you're most welcome 😉

Mabula

I'm enjoying reading the Forum and picking things up.

On debayering, my camera is a QHY128C, which is an OSC using a Sony IMX128 color sensor, also used in the Nikon D600 camera.   I imagine that the debayering and white balance procedures are the same as on a DSLR camera.

--Bill

Hi Bill @bharris,

Excellent 😉

For your QHY128C you might need to tell APP that it needs to be treated as Bayer CFA data. So enable the Force CFA checkbox in 0) RAW/FITS and set the correct Bayer CFA pattern. Than all should work fine.

Such an astronomical camera doesn't have a camera white balance function like a Nikon D600, which also isn't a problem.

Background calibration and Star Color calibration can and should be done after you have integrated/stacked your data.

Let me know if this helps 😉

Mabula

Hi, Mabula,

 I'm experiencing an issue with the "force CFA" setting... I'm trying to integrate RGGB data from a ZWO ASI071MC (needs Force CFA) with luminance/Ha data taken with a ZWO ASI183MM (must NOT have CFA) : the problem is that the "Force CFA" setting appears to be a global, applied at processing, rather than a property of the light frame, applied (sticky) at load time, so with all of my lights loaded, I either get a fault that the light has 3 colour fields but the flat only has 1, or vice versa... the frame display reflects this, always showing the 071 frames as 16-bit grayscale, CFA no

Any suggestions?

Well, true to form, software makes me a lier!

 I’ve just tried again, regenerating the master bias & flats, then loading the RGB data, calibrating and star analysis: then, I unchecked CFA, loaded my luminance data, whereupon APP correctly assigned MB & MF, and performed star analysis. The only difference I can recall (this was whilst capturing data early hours of this morning), is that first time, I tried to load all the lights before doing star analysis...

Sorry for the false alarm

Carl

Posted by: celkins

Hi, Mabula,

 I'm experiencing an issue with the "force CFA" setting... I'm trying to integrate RGGB data from a ZWO ASI071MC (needs Force CFA) with luminance/Ha data taken with a ZWO ASI183MM (must NOT have CFA) : the problem is that the "Force CFA" setting appears to be a global, applied at processing, rather than a property of the light frame, applied (sticky) at load time, so with all of my lights loaded, I either get a fault that the light has 3 colour fields but the flat only has 1, or vice versa... the frame display reflects this, always showing the 071 frames as 16-bit grayscale, CFA no

Any suggestions?

Hi Carl @celkins,

Welcome to the APP forum 😉

Indeed the Force CFA setting is global. It will try to process 1-channel data a Bayer CFA data if enabled.

In your particular case, I would recommend the following:

Calibrate your CFA data from your ZWO ASI071MC and the luminance data from the ZWO ASI183MM separately.

Enable Force CFA with the ZWO ASI071MC before creating the calibration masters, the Masters will be CFA frames then 😉

Disable Force CFA with the ZWO ASI183MM.

In 2) Calibrate, you can save the calibrated light frames. The CFA light frames will be stored as CFA calibrated frames, so those will not need the Force CFA setting anymore, because APP will have added metadata to indicate these are CFA frames.

Then after having correctly calibrated all of your frames (always double check if calibration works correctly), RGB and luminance, make sure that Force CFA is disabled and load all of the calibrated lights and proceed as normal 😉 with 3) to 6).

This workflow should ensure all is fine and that all data is correctly registered and normalized to each other 😉

Kind regards,

Mabula

Posted by: celkins

Well, true to form, software makes me a lier!

 I’ve just tried again, regenerating the master bias & flats, then loading the RGB data, calibrating and star analysis: then, I unchecked CFA, loaded my luminance data, whereupon APP correctly assigned MB & MF, and performed star analysis. The only difference I can recall (this was whilst capturing data early hours of this morning), is that first time, I tried to load all the lights before doing star analysis...

Sorry for the false alarm

 

Carl

No problem Carl @celkins 😉

Posted by: Mabula Haverkamp - Admin

Hi Bill @bharris,

SNIP

Such an astronomical camera doesn't have a camera white balance function like a Nikon D600, which also isn't a problem.

SNIP

Let me know if this helps 😉

Mabula

The QHY128 camera manual has a section on setting the white balance in the Setup Section.  I've not tested the camera extensively, but I suspect that there is a firmware/software correction applied to the camera output software.  The instructions seem a bit sketchy, and "color balance" is an odd concept, anyway.   I'll check the camera out closely.

--Bill

Posted by: bharris

Posted by: Mabula Haverkamp - Admin

Hi Bill @bharris,

SNIP

Such an astronomical camera doesn't have a camera white balance function like a Nikon D600, which also isn't a problem.

SNIP

Let me know if this helps 😉

Mabula

The QHY128 camera manual has a section on setting the white balance in the Setup Section.  I've not tested the camera extensively, but I suspect that there is a firmware/software correction applied to the camera output software.  The instructions seem a bit sketchy, and "color balance" is an odd concept, anyway.   I'll check the camera out closely.

--Bill

Hi Bill @bharris,

Okay, let me know how it works, I wasn't aware that such a camera would have such a function.

Mabula

I just read this - it debayered my subs. I called one up.  Looked horrible due to my LP and filter (green) I clicked neutralize BG and BAM.  Im' sold. = )

Hi, I'm new to this forum and am trying out APP in the 30 day trial.  I've got a ZWO ASI294MC pro 1 shot camera and can't seem to Debayer.  

I've tried forcing CFA and also switched between supported and RGGB but can't get colour - I'm sure I'm doing something wrong and have also looked at your DSLR video as that seems to be the best fit as a 1 shot colour, but any help would be appreciated.

On another related matter, when I view a light or dark file, all I can see in the image preview is a black screen - is there a view/not view button that I've missed ??

Many thanks

Graham

Mm, it should work when forcing CFA is checked. You can send one light of your camera directly to me if you want? vincent@astropixelprocessor.com

@vincent-mod

Hi Vincent, thanks, I've sent you an email.

Regards

Graham

Going to look at it now, thanks.

So, APP doesn't see it as a color camera, but I do get a mono picture straight away, changing to force CFA and it seems fine..

I think it may be a Version issue with the Mac Operating system.

On my iMac which uses Hi Sierra it doesn't load, but on my old MacBook which uses an older operating system, El Capitan, it loads fine !!

Graham.

Is it a possibility to update the iMac to Mojave by any chance? It's interesting nonetheless and I forwarded this to Mabula..

@vincent-mod

Hi, sadly I can't as the iMac is a 2010 one - I've reached the max potential.  However El Capitan is an even earlier version and it works on that !!

Graham.

Yes that could be some random change Apple made in a certain feature used by APP. That's a known issue with Apple sometimes. I hope @mabula-admin can have a look.