DSLR processing

[Josef]

Hi all,

I would like to use the PixInsight for DSLR picture processing, but there is any script or function transfer CRW (CR2) to FITS or TIFF (non debayering). Do you have any idea, how I can transfer a RAW image to these formats in PI? Now I am using Nebulosity 2.

Josef

[Carlos Milovic]

If I am not wrong, there is an option to open raw images without debayerization. Then, the opened grayscale image may be saved in any format.

[Josef]

Please, where is OPTION for opening RAW without debayerization?

My imagination was transfer all RAW pictures at a time to FITS and made by scripts BIAS, FLAT and DARK - it is easy and fast. Is there any possibility make a scripts which run DCRAW -D -T -4 or with any parameters?

[Carlos Milovic]

Go to the Format Explorer, and select the RAW one. Expand the menu to the right, if collapsed (arrows in the bottom button). Now, press on the "Edit Preferences" button.

This will open the RAW options window. In the middle, there are three checkboxes. The second one reads "Create RAW Bayer picture (no interpolation, no debayerization). This is what you are looking for. Enable it.

[Josef]

I have tested it, but I can see only RGB picture (3 layers). This option not working.

Reading 1 image(s):
/Users/josef/Desktop/M45_1/IMG_7880.CR2
Invoking: dcraw -D -t 0 -o 0 -4
Decoding Canon EOS 40D file (3908x2602 pixels, ISO=1600, Exposure=1/363s): 100%
Loading raw image: 100%

I can make hand order dcraw -D -T -4  it makes a TIFF file and it is no debayerized! Your order dcraw -D -t 0 -o 0 -4 normally make .ppm (3 layers) file. You must use dcraw -D -o 0

[Carlos Milovic]

Thanks. We'll fix this for the next release (in just a few days).

[Cheyenne]

The procedure that I have been using for processing Canon raw images in the wiki  http://wiki.pixinsight.com/tiki-index.php?page=Calibrating+RAW+Images   Also there is a discussion in the forums about processing DSLR raw images (see the link below)

Carlos, you might want to talk with Juan when you are "fixing" the raw format.  He indicated in another post that it might not be fully straight forward -> http://pixinsight.com/forum/index.php?topic=1273.msg6370#msg6370

[Josef]

.ppm is not usable format for processing. TIFF (no debayerized) is very good. I can use Processing Console in PI for transfering CR2 to TIFF in my OS X:

DCRAW and PI is on the Desktop, a picture is in folder M45_1.

1. Open Processing Console
2. Write : chdir /Users/josef/Desktop/
3. Write : !./dcraw -D -T -4 /Users/josef/Desktop/M45_1/IMG_7874.CR2
That transfer CR2 file to TIFF file.

[Carlos Milovic]

Hi Cheyenne

If this is only a matter of changing a pair of parameters, it will be done... of course, last word is from Juan. He is the boss (actually, we all know that it is his wife... but we let him believe that he is in charge)

[Cheyenne]

What I infered from Juan's post  was that the raw format processor produced an RGB image and not a grayscale image when turning off the debayer option.

Basically, the output from raw format needs to be in grayscale to allow proper calibration, once calibrated, then the image can be converted back to rgb using the debayer process module.  -- at least that is my understanding

Ah.. yes... "I'm the one who makes the rules in the house, and I have my wife's permission to say so"

[Astrocava]

Hi all!

We can use PI to get a grayscale raw image:

1. Open the image with the Create RAW Bayer Picture option checked
2. Extract RGB channels. We get 3 gray images, one for each color
3. With PixelMath we sum the three images, obtaining our gray bayer picture.

Hope this helps.

Sergio

[Cheyenne]

Just checked, and that process does work.

I took a raw canon cr2 file converted to a tiff (using dcraw -4 -T -D ), read the tiff into PI, and used the debayer process module.

I then took the same canon raw file, read directly into PI, with no debayer, channel extracted the three channels, added the R, G, B together and debayerd the result.

I then took the two debayered images and subtracted them.  The resulting image was all zero.

So.. I think a simple option to the RAW file processing would be to have a choice to either create an rgb or to combine the three channels and create a greyscale image.

[Nocturnal]

DeepSkyStacker can also be used to save calibrated and/or registered lights in un-debayered FITS or TIFF format. I haven't done this myself but you could check it out if you have a Windows box.