Hello, I tried to use darktable to invert a negative scan using my camera. The result is only okay in my opinion and I feel the color is a little on the digital side. In short, I’m not happy with the result. I would like to learn more about how others do this. Just do it in your way, with your taste. Don’t be affect by my comments. That also means any opensource tools is fine, not only darktable.
Never done a film scan before! Had a quick look what Rawtherapee might produce. Tuned the colours towards what i remember Fujifilms looking like… off the cuff like
I don’t have any experience with colour negs, although I have done quite a few B&W negatives. I think I should read the negadoctor section in the DT manual. I’m not quite sure how to handle white balance.
In this case, I set WB to ‘as shot’ (i.e. legacy workflow), then moved the color calibration module after negadoctor and used it to warm up the image which seemed rather cool after negadoctor had removed the colour of the film base… I don’t really know what I’m doing!
Thank you for posting - lovely photo. May I ask if it’s taken in Japan?
It always helps of you have more (or all shots) of the same roll, all ‘scanned’ at the same exposure.
Setting the eventual black level is easy most of the time , it is the film strip.
Setting the eventual white level is the tricky part (as it influences the color cast for the largest part ). Having all pictures of the roll to try to set it for all at once is often easier. You can then always tweak each image individually if you want.
Be careful @Ngoc your backlight is not even horizontally and vertically, or it may be corrected using Lens correction module, or it’s both the backlight and the lens. If you could provide the lens model used on your Sony Camera because that information is missing, it will be nice ^^
I’ve tried to correct that using Exposure.
I made a standard edit without thinking too much :
Exposure is set so, while watching the parade histogram, the brightest in the red channel is bellow the max.
Color calibration is deactivated because there is no information about the light source you are using.
Dmin in negadoctor measured in the empty area on the left of the picture.
Dmax measured on the sun spot.
Exposure bias auto measured over all the picture
Then some back and forth between Corrections and Print Properties tabs
Print Properties tab : Auto set Paper black, then set Print exposure and Paper grade as wanted. Correction tab : Shadows were quite cold, so I lowered blue and greens. Then adjusted Highlights by increasing red and a bit of green.
Now the picture is color neutralized, I do a Color grading in the Color balance module :
in the Preceptual saturation settings, I invert the standard settings of shadows and highlights’ sign (20 → -20 and vice versa). This is because it’s negative film and it misses saturation in HL, which is usually the contrary with digital pictures.
Then I made some color grading in the 4 ways tab (don’t forget to click the color picker of White fulcrum in the Masks tab before).
I found this old video from Aurelien useful as a tutorial
Also, this suggestion from @Claes was very useful:
“In darktable, also invoke the rgb levels module. Click the auto button. That will bring up your whites”
Personally, I also moved any modules where I am adjusting the edit after (above) negadoctor in the pipeline so that the sliders don’t operate in the opposite direction to a normal (positive) file
Thank you, everyone, for your takes on this image and advice. Apparently it’s hard to achieve original film look without using any kind of LUT.
@123sg Hi Steven, yes I shot this last autumn in Tokyo. Japan just looks amazing in autumn.
@Jiyone Hi, thank you for very detailed post. I “scanned” the image with a Zuiko 50mm f3.5 macro and 26mm extension tube. So that’s why you don’t see a lens information. I will definitely check my backlight situation. Just curious, how did you know my backlight is uneven?
You can see it if you draw a square with the color picker over a black border space on the top or the bottom, it should be a straight horizontal line in the waveform histogram.
this kind of shape is typically a lens vignetting issue or just missing light in the corners.
