New Tool Released: SpectrophotometricColorCalibration (SPCC)

I don't understand why there is a white balance/reference dropdown.
If I wanted it to be made 'pretty' I wouldn't be doing the calibration in the first place.
from what I know white balance/reference is only in case the light source on a object you photograph isn't what you want it to be, so you change that in post, but never when the light source is what you photograph like in astrophotography.

When calibrated I want them calibrated not be 'post pretty' again.
So what do I need to select to make the white balance an empty action?
It's just a matter of what you want to show in your image; the Pleiades portion in the documentation is a perfect example.
 It's the same as in normal photography; if you have a warm light and a cold light in the same frame, you have to choose which one to make white - or find a balance between them.
If this doesn't interest you, then use the default; average spiral galaxy.
 
Never mind - I found it on the PI SW Distribution web site.

BTW - It took my 8 attempts to download the new PI updates, most likely due to heavy traffic. Trying to download the GAIA databases now...
I'm having slow downloads and network errors for this download also. It's December 9.
 
I'm having slow downloads and network errors for this download also. It's December 9.
Update. Tried again at 6:44 EDT (east coast USA) and downloads completed in about 4 minutes per 3GB bundle. So it may be a function of network traffic between PI servers and my location in USA. Previous failures were started at 5:17 EDT.
 
I don't understand why there is a white balance/reference dropdown.
If I wanted it to be made 'pretty' I wouldn't be doing the calibration in the first place.
from what I know white balance/reference is only in case the light source on a object you photograph isn't what you want it to be, so you change that in post, but never when the light source is what you photograph like in astrophotography.

When calibrated I want them calibrated not be 'post pretty' again.
So what do I need to select to make the white balance an empty action?

Again:

In PixInsight, we have always favored a relativistic view of color in astrophotography. This is well described in the book Fotografiar lo invisible, by Vicent Peris:

Under the relativistic perspective, the same natural object does not have a single authentic balance of color, since this color is always relative to its frame of reference. And this frame of reference, in turn, depends on the physical phenomenon that you want to convey in the image. Therefore, color in astronomical photography acquires a meaning in its own right, since in these images we can discuss in a specific and accurate way what the white balance and each of the color hues physically represent.
From this point of view, an image can have multiple color perspectives, depending on the natural content we want to convey.

By having a choice in the white reference, you aren't choosing between calibrating and not calibrating. If you don't calibrate, your relative color data is inaccurate. There's nothing about a white reference that says it can't be based on objects that produce their own light (as opposed to, say, objects that are lit by an external source).
 
I cannot find these files when I open the Gaia process and drop down Gaia DR3 or Gaia DR3/SP. When I click on the wrench icon, nothing is in the database files. I've downloaded DR3 and DR3/SP Full Version and placed them on my hard drive in a folder I named. Am I doing something wrong? Well, obviously I'm doing something wrong, but can someone tell me what that is?

Thank you!

Scott Gaia.JPG
 
In the shown window ("Gaia Preferences"), click on 'Select'. A file dialog will open. Navigate to the folder containing the appropriate database files, select them and confirm with "OK". The files must be displayed in the list.

Thereby you tell the Gaia process where the database files are residing.

Bernd
 
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Do you mean where they can be downloaded from?
I'm sorry, I was unclear. I've downloaded them and placed them into the same folder. I've seen on this thread that you need those two files to get Gaia to work properly. My question is - Where in Gaia do I put them?
 
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The APASS databases are used with the PhotometricColorCalibration (PCC) process which now is superseded by SPCC. So if you intend to continue using PCC, you'll need the APASS databases and these must be configured (analogously) in the APASS instead of the Gaia process.

Bernd
 
The APASS databases are used with the PhotometricColorCalibration (PCC) process which now is superseded by SPCC. So if you intend to continue using PCC, you'll need the APASS databases and these must be configured (analogously) in the APASS instead of the Gaia process.

Bernd
Oh, got it. Thank you! I will not need them, since I plan on using only SPCC.
 
In the shown window ("Gaia Preferences"), click on 'Select'. A file dialog will open. Navigate to the folder containing the appropriate database files, select them and confirm with "OK". The files must be displayed in the list.

Thereby you the Gaia process where the database files are residing.

Bernd
Also, after you have added the files to the list, you need to click the "apply global" (circle) icon at the bottom to get the GAIA process to complete the registration of the database files.
 
Question for experts:
With SPCC release does it still make sense adding RGB stars to narrowband images?
Would SPCC present star colors as they are supposed to be based on S,H,O channels without adding a separate set of RGB images for that very same purpose?
Thanks in advance for all answers.
 
Would SPCC present star colors as they are supposed to be based on S,H,O channels without adding a separate set of RGB images for that very same purpose?
The whole purpose of the Hubble SHO (and other similar) false colour images is to choose a colour mapping that is not photometric, but rather highlights the scientific content of the image (e.g. which different regions emit strongly in H-a, S-II and O-III). SPCC can do it's best to photometrically calibrate the image, but that is hardly ever the effect that the astrophotographer is looking for. None of the published Hubble "SHO palette" images are photometrically calibrated. Careful merging of an SPCC-calibrated broadband RGB image with suitably processed narrowband data can give a combination of photometrically correct star colours and enhanced false-colour presentation of non-stellar content, but there is no simple "PHD" process for this.
 
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Another slow download rate question. Based on Post #122 comment, how many of the DR3 and the DR3/SP files do we actually need? I live in a rural area, no high speed internet available. A 3GB download normally takes 30 mins. And I need to hit “resume download” often. Reading this post in entirety and will start reading SPCC doc next, and I just started 2nd file. Is number of files required based on FOV?
 
The whole purpose of the Hubble SHO (and other similar) false colour images is to choose a colour mapping that is not photometric, but rather highlights the scientific content of the image (e.g. which different regions emit strongly in H-a, S-II and O-III). SPCC can do it's best to photometrically calibrate the image, but that is hardly ever the effect that the astrophotographer is looking for. None of the published Hubble "SHO palette" images are photometrically calibrated. Careful merging of an SPCC-calibrated broadband RGB image with suitably processed narrowband data can give a combination of photometrically correct star colours and enhanced false-colour presentation of non-stellar content, but there is no simple "PHD" process for this.
So would I be right in thinking this also applies to OSC images taken with a duoband filter? (in my case 7nm Ha / Oiii)? As in, there is not much point in my running SPCC since the star colours won't be close to 'real' in any case
 
I have been using SPCC trouble free since its release.
I had previously downloaded the SMALL SET of DR3/SP.
Today, for no apparent reason, it stopped working. I keep getting the following error:

*** Error: Invalid Gaia DR3/SP XPSD server execution: Couldn't retrieve a valid spectrum wavelength table.
 
How do I know which filter to choose if the exact one isn’t listed? I have a Canon RA and T7 (EOS 1500D) and there are at least 13 Canon filter types listed, none are Canon RA or T7.
I seems to me that if the correct filter is not chosen, the colors will be off.
 
Is it possible to add a specific filter to the tool ?
I saw someone had a specific Optolong L Extreme added on a recent youtube video this is of interest to me as its a filter I often use.
 
Is it possible to add a specific filter to the tool ?
I saw someone had a specific Optolong L Extreme added on a recent youtube video this is of interest to me as its a filter I often use.

It's already there. Scroll down to Sony CMOS or Canon Full Spectrum, depending on your camera of course.
 
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