Nikon D850 - Astrophotography - having a tough time processing RAW


I did some astrophotography, but processing the raw files is not going well, any suggestions would be geatly appreciated, see the uploaded exampleDSC_0976.NEF (49.6 MB)

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Could you explain what your difficulties are, So that others may offer solid suggestions?

DSC_0976.NEF.xmp (3.2 KB)

darktable’s filmic module on auto with a tone curve. It’d be nice to know what lens, it looks like it could use some vignette correction.

Excuse me to hack the thread

DSC_0976-1.jpg.out.pp3 (12.0 KB)

I’m using a 28-70 zoom lens, shooting at 28mm. I pushed the ISO to 1000 which I did not think was too much but the images seem VERY grainy when I zoom them even a little, for example setting it as a background on my monitor, which makes me concerned about printing them

Two RawTherapee 5.6-dev exposures gradient masked together in Gimp 2.10.12.

skyDSC_0976.NEF.pp3 (11.3 KB) DSC_0976.NEF.pp3 (11.3 KB)


Can you share details how you did this?

@HIRAM Lovely masking and result.

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To get the sky I stretched the contrast a little with a few different tools.


For the trees in the foreground I raised the exposure/brightness.

In Gimp, import both exposures as layers. Add a layer mask to top image. Draw gradient with tool on the layer mask. Adjust color curves and noise reduction.

I first made two copies in darktable:
Dark DSC_0976.NEF.xmp (3.7 KB)
Light DSC_0976_01.NEF.xmp (4.9 KB)

Then combine them with darktable enfuseAdvanced.lua plugin with the following settings


Finally adjusting the jpg-image DSC_0976_01-0976.jpg.xmp (2.1 KB)
Removed hot pixels in trees with gimp/gmic

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Here’s my attempt at a darktable only edit. Most of the adjustments were done with the filmic module along with a few instances of the exposure module with various masks. The sharpening and noise reduction could probably use some tuning but I’m relatively pleased with the result.

DSC_0976.NEF.xmp (16.7 KB)


@HIRAM I really like your version, but pleas rotate the image and make the coastline straight.

First - two jpg from RT with different exposures. Then mixed in GIMP 2.10.12. I was suprised by the need to correct strong vignetting effect in the basic NEF file

DSC_0976…jpg.out.pp3 (11.5 KB) DSC_0976.jpg.out.pp3 (11.5 KB)

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@ltr21 Welcome to the forum! And nice result. :slight_smile: