So many different colours from Nikon Z50

[Jim Smith]

I took some shots of the Horsehead Nebula with my Nikon Z50 on my 8" f/12 Cassegrain. 30 seconds. ISO 1600. The white balance was set to "Direct Sunlight".

Below is a sample of some of the .tif files exported from LrC ready for stacking. As you can see, there are a variety of different colours. The raw files were the same.

What might be causing this?

Thanks, Jim

[michael8554]

5 hours ago, Jim Smith said:

.tif files exported from LrC

What is LrC ?

Michael

[Jim Smith]

Lightroom Classic

[Jim Smith]

When I said "the raw files were the same" I meant to say "the raw files were all different colours too"!

[alacant]

9 hours ago, Jim Smith said:

What might be causing this?

Hi

Those look like debayered, resized and processed (as in simply to make them viewable by humans) thumbnails. 

If your software can't deal directly with Nikon raw, I'd recommend first converting to fits, followed by applying bias and flat frames before stacking. Using Siril.

Then process it.

Cheers and HTH

Edited December 1, 2021 by alacant

[Jerry Barnes]

I used to stack nef files from my Z6 in Deep Sky Stacker before getting a cooled camera.  I dont know if there have been format changes with your Z50 but it would be easy to check and its less work than processing in lightroom first.

[BCN_Sean]

Only thing I can think of here is that either you, or your import settings have zero'd the images in LR and that's been rendered at export time.  Whilst I like Lightroom for nearly all types of photography, it's been my go to since before it was Lightroom, I'd suggest the same as @alacant and go with SiriL for the conversion.  There's too many things in LR (and other similar things) that can potentially adjust the data that can catch out the unwary or tired without realising that it's happening (default noise reduction in Lightroom/Photoshop Camera Raw tries to map out hot pixels, as an example).

[Jim Smith]

Last night I took some more exposures with my Z50 and they were all fine. They all had the same overall hue. There was a difference though. I was using my 5" Newtonian which is much faster at f/5 than the f/12 of my Cassegrain.

I had to increase the exposure of the original batch of multicoloured images by about 3 or 4 EV in Lightroom to see much at all. I think the problem may have been caused by underexposure.

I usually use Lightroom to review my images then stack in Deep Sky Stacker or Affinity photo. I will take a look at Siril as advised.

Thanks, Jim

Edited December 2, 2021 by Jim Smith
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