New member with digitizing issues

Hey all, I have been lurking on here for a while and decided to join as I have been having quite a bit of difficulty digitizing color negatives. I decided to use a copy stand with a bellows focusing unit for the front of my DSLR and then put negatives on top of a light box. It works really well with black and white but I can't for the life of me figure out how to get a better image with color negatives. The top one is from a local film shop and then I tried capturing the negative myself to practice. I can't get anything close... I tried using Vuescan and using the correct film stock but that gave me the image below. Really gross looking.

 

Any helpful tips for a newcomer that feels in over their head with color film?

 

Colour negatives have an orange mask as part of the C41 process, which is tricky to correct for. After scanning or digitising them it's often necessary to make further manual correction to the colour balance, using an image editor. In the example given, which has something of a blue cast I used the Color Balance tool in Photoshop. You could also use Levels, and click the centre eyedropper over an area which should be neutral grey.

 

And welcome to photo.net

 

Tools like levels and colour balance are too crude to correct this sort of colour error.

 

You need to use the curves tool, which allows you to alter the contrast and distribution of the red, green and blue channels individually.

 

The curves tool takes some practise to use, but is probably the most powerful correction method available.

 

In the image above, you have blue shadows and yellow highlights - however, there's something else going on. The blue imbalance is limited to a patch in the centre of the frame, which makes the overall colour impossible to correct. There's also a vignetting effect.

 

I suspect this is due to the light box you're using to illuminate the film. Perhaps ambient light is being reflected back from the film and contaminating the back-illumination. Try turning the room lights out when copying the negative. If that still doesn't work, then you likely need to change the light box.

 

I much prefer flash as the illuminant for copying. Its colour is close to that of daylight, and its bright enough that ambient light has little effect.

 

This is the best correction I could get in a short time by using the curves tool. Far from satisfactory. The yellow surround can't be corrected without turning the centre blue again.

 

Incidentally; the print from the local shop isn't that great either, and has a slight red cast.

Edited May 14, 2018 by rodeo_joe|1

Open shade is difficult to handle when converting negative to positive color, even with a dedicated scanner (e.g.,Nikon LS-4000). Converting from an image of the negative from a digital camera presents difficulties of its own.

• Set the camera's white balance from the light source.
  
• Shoot the negative using this setting.
  
• Color conversion is strongly dependent on the exposure level. Try auto exposure in the camera, but be prepared to set it to a fixed value.
  
• Try the negative conversion option in Photoshop "Curves"
  
• If that doesn't work, use Levels (histogram)to set the boundaries for each primary coloring the negative image before inversion, then invert the colors (ctl-I)
  
• Adjust the positive image using various tools in Photoshop or Lightroom (recommended)
  
• You can use these tools to adjust the white balance, tint, contrast etc. You can also use color channels for more flexibility (and difficulty).
  

In practice, you can only get one color right, often at the expense of other colors. For if shaded faces look right, the sky might be slightly pink. Sunny 16 conditions are the easiest to work with. Everything else is a challenge.

 

Finding a neutral white, grey or black for use with an eyedropper is a waste of time, unless you have a real standard card in an image taken under identical conditions. Even then, using calibration software, is not uniformly successful.

Yes, the subjects are in shade, which will require a slight correction. However, that doesn't explain the obvious 'blotch' of deep blue in the centre and bottom of the picture, while the edges and top are almost purely yellow.

 

It also doesn't explain why the minilab print shows no such division.

 

This has to be a 'hotspot' effect from a poorly diffused illumination of the negative, or some random reflection from the film surface having a grossly different colour temperature from the backlighting.

Reflection of room light is a strong possibility. It is important to shield the film from extraneous light. It would be useful to profile the light box with the same setup, making sure the light is uniform. Older lenses may have a hot spot or veiling flare due to reflections between the sensor and the lens itself in high-contrast situations. It is best to use a macro lens to copy slides. Ordinary lenses pushed to 1:1 have curvature of field and sharpness issues in general.

Yes, the subjects are in shade, which will require a slight correction. However, that doesn't explain the obvious 'blotch' of deep blue in the centre and bottom of the picture, while the edges and top are almost purely yellow.

 

It also doesn't explain why the minilab print shows no such division.

 

This has to be a 'hotspot' effect from a poorly diffused illumination of the negative, or some random reflection from the film surface having a grossly different colour temperature from the backlighting.

 

This is exactly my issue. If it was all blue or all yellow, I could understand that but the center is muuuuuch cooler than the edges and the edges get continually warmer as it goes. I will keep messing with it but at this point I will likely just send my color film in to be processed and captured until I can get better at it. The black and white film has been wonderful to capture so I will keep using that to boost my confidence! :)

Adam, cheap slide/film copier attachments can be found easily. They're not as good as a proper macro lens, but they're pretty bullet-proof.

 

You can just stick 'em on the front of the camera, and you're pretty much good to go.

 

Since the camera + copier assembly is fairly rigid, you don't need a tripod or copy stand. Just point the copier at a light source and press the button.

 

I actually much prefer flash for consistency and to quell any chance of vibration blur. You can just use on-camera flash pointed at a white card placed in front of the copier.

Hi Adam,

 

maybe you can use Colorperfect (or of course first try the free demo, althought I think the results from the full version are better than from the demo.)

 

At the moment I'm digitizing the old slides and negatives from my parents and grandparents with a camera and although I don't have your specific issue, getting acceptable colors from the negatives was a struggle. Tried doing it all manually in either LR or PS, spending a lot of time for each photo, with bad results. There are some plugins you can find that apply levels and curves and the conversion automatically, which for me gave much better results with just a few mouse clicks. But still the colors seemed not right, a bit radioactive if you will, especialy greens. Because of this I finally decided to purchase Colorperfect, which I didn't do earlier because the price seemed a bit high for me. In my opinion the results are much better, far more natural. The colorperfect conversions are generally with lower contrast, but this can be added easily. Sometimes auto tone or auto color in PS improve things a bit more, but not always.

 

Here is an example of the difference in results I get. The first is a conversion using one of the levels/curves plugins, the second Colorperfect.

 

 

Of course there are some downsides. The biggest for me is that you need to create linear tiff files with their MakeTiff software. Although this very simple, just dra and drop files or folders, I don't like to create these large extra files. But the results are worth it for me. (After experimenting I found that setting the colorspace in Maketiff to Adobe gave tthe best results). And the Colorperfect plugin in PS is bit clunky to use and understand. Because of this I don't mess with the settings too much, just select the film type really. If the used film is not in Color[erfect, you can just go through the others to find something you like, or using the left mouse button in a neutral area set a whitebalance .

If you'd like to I could also run the file through my full version of Colorperfect to see if this would improve things.

Vuescan...is it's own thing. Think of it like a piece of factory machinery: it does the steps it does very well and with minimum fuss once you've built it into your workflow. But it takes months or more to get used to all the little idiosyncracies of Vuescan, and it's not a general-purpose piece of software like Photoshop or even Lightroom. Vuescan is very directly geared toward scanners, and scanners that output high bit-depth at that. It's a great way to get strips of film scanned to files with no information lost to clipping that you care about and with the color mask pretty much perfectly removed. If you're adventurous you can even have it do your levels and get automatic color. While it has camera raw features it's mostly an afterthought and doesn't have nice camera oriented features like really good vignetting correction. In your case I would process using a camera raw software that can fix the vignetting, and/or stop down your lens to f/5.6 or 8 and output to high-bit tiff with as little processing for contrast as possible. While you could feed into Vuescan after that and try to use it to fix the colors, once you've got all 3 channels with good unclipped histograms you can invert and do levels/curves yourself probably just as easily in the next tool down the line. As long as it's not Elements.

Seems like adding to this thread might be a waste of time. Adam, the OP, joined PN the day he posted his query, and last logged into the site the day after!

 

Like many mystery problems posted on PN, we may never get to know what the real answer was; which is a pity, since knowing may have helped others down the line.

Another fly by.

 

Rodeo: what is your avatar a photo of. Looked at for ages now and I still can't figure it out.

Another fly by.

 

Rodeo: what is your avatar a photo of. Looked at for ages now and I still can't figure it out.

 

It's a self portrait taken by reflection from double glazing, with a flash atop the camera. I know it looks like I'm pulling a weird grimace at small scale, but that's an artefact of the double image. I might change it for something a bit less surreal.

Yep ok. I would have worked that out in about 100 years.