Night raw .nef looks way worse than in Windows photo

Discussion in 'Beginner Questions' started by elmarkidaz, Nov 26, 2020.

  1. Hello,
    I'm new to this community and software photo editing.
    Those were my first Milky Way pictures from a year ago and now I tried to edit them.
    For editing at the moment I'm using GIIMP + RawTherapee.
    I know that raw pictures can look a bit bad sometimes and not like on the camera preview or the jpg, but those looks like two completely different pictures.The raw on RawTherapee is really bad, all noise, strage colors and a circle effect.
    .
    The preview on camera and the Windows photo ones looks similar and pretty good to me.
    The first is the RAW, the second is the Windows Photo viewer(both are low quality screenshots especially the second).

    Do you know how I can edit it correctly to look like the preview one? Because it looked like a good starting point to edit.
    Thank you.

    (edit) Here watching in little and low quality, the raw seems not that bad..
    As seen on RawTherapee.jpg As seen on Windows Photo.jpg ,
     
  2. Hard to tell from those but my very limited experience with astro shots was that noise reduction was fussy and sometimes the camera manufacturer could do a better job with the jpegs than I could with the raw. With my Nikon, I think their PC raw processing program had a special checkbox for astro images. You have to get the dynamic range just right and not over-sharpen, as that makes the noise stand out. What camera are you using? Can you post a link to a raw image?
     
    elmarkidaz likes this.
  3. JPEG images, which are what you see in Win Image Viewer (urrrgh!), are processed to include vignetting correction - the dark outer circle - and noise reduction.

    If these enhancements are applied to the RAW file to same degree, then you'll end up with exactly the same looking image as what you see in Image viewer.

    You need to understand that a RAW file is exactly what it says; a file containing the raw data direct from the image sensor. That's as good as it gets. Warts and all.

    The whole point is that a RAW file can be processed to remove those warts far more thoroughly than what can be done with the camera's limited CPU power. And to make use of the full bit-depth captured by the camera. This is usually 12 or 14 bits and gives far more flexibility for enhancement than the 8 bit limit of a JPEG image file.

    Bone up on the possibilities of high bit-depth image processing, and you'll see the advantage of shooting RAW. But not if you just let lame default adjustments apply themselves.

    P.S. Top quality RAW processing software, like CaptureOne, can produce results that blow away anything you can get straight out of the camera.
     
    Last edited: Nov 26, 2020
  4. I'm a complete amateur here but for me, your question breaks down into a couple of stages:
    - in principle, a raw image contains only the light intensities and color information that reach your camera sensor
    - in order to view (and possibly edit) this raw data, you'll need a reliable raw data viewer/editor and a reliable screen
    - All JPEG applications compress files by averaging blocks of pixels. Some may (as default) 'enhance 'photos'
    - it's worth checking how your photos look in different apps on different devices,

    ------------------------------------------------------------------------------------------------------------------
    Those were my first Milky Way pictures from a year ago and now I tried to edit them.
    For editing at the moment I'm using GIIMP + RawTherapee.
    I know that raw pictures can look a bit bad sometimes and not like on the camera preview or the jpg, but those looks like two completely different pictures.The raw on RawTherapee is really bad, all noise, strage colors and a circle effect.
    .
    The preview on camera and the Windows photo ones looks similar and pretty good to me.
    The first is the RAW, the second is the Windows Photo viewer(both are low quality screenshots especially the second).

    Do you know how I can edit it correctly to look like the preview one? Because it looked like a good starting point to edit.
    Thank you.

    (edit) Here watching in little and low quality, the raw seems not that bad..
    View attachment 1366052 View attachment 1366054 ,[/QUOTE]
     
    elmarkidaz likes this.

  5. @conrad_hoffman Hello, thanks. I tried with the dynamic range on RawTherapee but it still have a lot of noise. I noticed that here the two pictures seems similar and not bad, but on RawTherapee it's basically a totally red picture, i even tried on two different pc with totally different specs...


    I have a Nikon D5600.


    Can I post the raw picture there on the forum? Or else how can i attach it?






    @rodeo_joe|1 Thanks, I used Windows Image Viewer only to know wich picture to edit :) Thanks for the explanation about the raw format and the different processes.

    But now, how can I get a picture that actually looks good as the jpeg one or even better? Do you know any good guide for noise reduction in post-production of night photography?



    @mikemorrell thank for the answer
     
  6. Since you have a Nikon, try Nikon Capture NX-D. You should be able to duplicate your jpeg, and then do better!
     
    elmarkidaz likes this.
  7. Thank you, I will install it in the weekend when I get back to the windows pc, because it's not available for Debian. I will let you know
     
  8. A little late, sorry.

    There are usually two stages to processing a RAW file.

    Stage one is to use a RAW converter, such as Raw Therapee, Adobe Camera Raw, CaptureOne, etc. At this stage all you (well I) attempt to do is get the white balance and exposure right - pretty much ignoring any other options offered. Although some Raw converters offer useful features like automatic vignetting, distortion and colour-fringing correction, if the lens used is in their database.

    In my view the job of a Raw converter is simply to de-mosaic the image and get it into a high bit-depth (16 bits/channel) form for further processing.

    Stage 2 is to import the 16 bit TIFF from your Raw converter into a full-blown image editor to do the heavy lifting of noise reduction, tone curve correction, etc.

    Personally, I would not attempt to do those things at the Raw conversion stage. But I suppose it depends on the capabilities of the Raw converter.

    Historically the capabilities of Raw converters have been quite limited. So my workflow has been moulded by this over many years. Coming to it afresh I would probably make more use of Raw converter editing abilities, but I just stick with what I know works.

    Nikon NX-D, like Photoshop, combines the Raw conversion and image editing into one package. I'm not sure if a Linux port is available for it.
     
    elmarkidaz likes this.
  9. Thank you @rodeo_joe|1 for the explanation! I will also try this method in the weekend

    Thanks, i will let you know
     
  10. Hello @conrad_hoffman and @rodeo_joe|1 , I found that the best option for me was to start with Nikon Caprure NX-D and already start just a little bit of noise reduction there with the correct camera settings, then save the Tiff 16bit file, then edit it in GIMP.
    I got a somewhat decent picture, there is still plenty of noise that i can't get rid of, but I think that I still have everithing to learn from shooting correctly at night to the variety of things that I can possibly do during editing.
    Would appreciate if you have other suggestions.

    I attach the (probably) final picture, thank you.

    View attachment try6.jpg
     
  11. I noticed that on different monitors and smartphones, it looks too dark
     
  12. I think that's pretty good.

    Astro-photography has a pretty steep learning curve, and sets of software all to itself that can make the job easier.

    A 'dark frame subtraction' might help. This is where you expose a frame with the lenscap on, with the same exposure parameters as are used for the sky picture - preferably at the same temperature too. This frame gives a noise base that can be subtracted from the star image to get a cleaner background.

    There are special optical filters available than can reduce certain types of light-pollution as well.

    Astro-photography can get very complicated if you let it!
     
  13. Thank you, I will inquire about this "Dark frame subtraction" and what I can do about that. Is that someting to set on the camera or a post-production tecnique?
     
  14. There's a pattern across the whole frame, I don't know where it came from but it looks like the "worms" you get when you use Adobe on a Fuji raw file took a growth hormone overdose. I don't know if it came from the raw conversion or the noise reduction or something GIMP did or what but I have to assume it's coming from software.
     
  15. It's post production.
    Something that specialist astro software can deal with automatically.

    Not so easy in GIMP or PhotoShop.

    Having said that; setting 'Long Exposure Noise Reduction' does much the same with some cameras. It doubles the exposure time while the camera takes a blank frame.
     
    Last edited: Dec 9, 2020
  16. Hello, where do you see those "worms"? o_O
     
  17. Ok, I will search if there is a software that can do a good job on that, thank you
     
  18. If you zoom in on try6.jpg, this pattern in the darks. (It looks the same on a desktop but right now it’s easiest to show using my phone’s screen capture.) 2752570E-B671-4930-915D-E3A879FC8533.png
     
  19. Oh ok, I didn't noticed that, it only appears there on the jpg, on the complete .tiff on GIMP it doesn't appear
     
  20. Okay. Weird jpg encoder thing it is then.
     

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