Nikon D5300 FIT/NEF debayer

Sequence Generator
1

This question comes in the “DSLR for Dummies” category…

I have a Nikon D5300 that I’m planning to use for the eclipse. I took some test images of the full moon last night and captured in both RAW/NEF and FIT.

When I open both files in Pixinsight, PI seems to automatically debayer the NEF file and it looks “right” in terms of color. When I try to debayer the FIT file in PI no matter what bayer pattern I use it always comes out with a strong color cast (green, magenta, blue…).

What am I doing wrong with the FIT file?

2

I should say I’m asking this question here because SGP records in FIT and normally that’s not a function of the camera. I can also ask this on the PI forum but thought I’d start here.

3

Hi
the default setting for raw dslr in pixinsight uses " camera white balance " where of course no such option exists
in "fits"
I personally would not use the default white settings :slight_smile:

Regards

Harry

4

So then how do you color balance the DSLR FIT files in PI?

5

Hi
there are lots of colour calibration tools in pixinsight ( some videos on my website) also inc the new PCC
tool which I will have to do a video on soon this works like this

  1. Plates solve your image
  2. gets a ref image from viser etc ( internet req )
  3. matches the stars in your image to the ref image ( with known colours )
  4. then based on the results of 3 it applies a colour correction to your image

Very cool indeed :slight_smile:
Harry

6

I haven’t yet tried the new PI, but I’m exited about this and other new
tools.

My question really has to do with solar and lunar imaging. The color
calibration tools that I’m familiar with in PI all use stars…which aren’t
present for eclipses or moon shots.
I still don’t really understand why my debayered FIT images have a strong
color cast to them.

7

Hi

virtually all fits files have a colour cast to them , as this is a true raw representation of the data from the camera

for various reason - light pollution - camera sensitivity in various channels etc etc .

I agree white balance is more difficult with the moon - in the PI way , but with a bright object a simple background neutralization will probably balance things out ok , some people just use DBE which work well

Harry

8

Those are both background neutralization things. I’m saying the moon
itself is green after debayer. BN and DBE does nothing to correct that.

Ah…this is why I’m a mono CCD guy. I just don’t get DSLR stuff.

9

hmm, BN + CC should fix the problem as long as you have the channels locked when computing the STF (after doing BN/CC). before doing BN/CC, an STF with the channels unlocked should also look pretty correct.

you should be able to white balance on the moon itself using the “old” ColorCalibration tool and the colors should be reasonably correct.

rob

10

Thanks Rob. This is all just because I don’t know what I’m
doing…obviously.
BN and ColorCalibration on the moon worked reasonably well.