Converting this negative to a positive
I am trying to convert this negative scan (Kodak Portra 160, scanned with SilverFast 8 and in the Mode "48bit HDR RAW"): https://dl.dropboxusercontent.com/u/465 ... 6%2001.tif (sorry, 150MB)
to a positive that looks somewhat similar to this:
https://dl.dropboxusercontent.com/u/46581632/result.jpg
I just can't get the capture one tools to work the way I expect them to. The tools that work fine on digital camera files just don't work for this file.
Especially, when I use white balance on the negative (before I inverted the colors using the "Levels" tool) it never shift the colors so that the picked point is a neutral gray (that's what white balance is supposed to do, right)? When I use the white balance tool on the light part of the wall in the background, there is still a color cast, even at the point where I picked the white balance. Shouldn't the background wall appear in light gray with no color? Could there be something wrong with the tiff file?
Can you give me a tip how to adjust the above negative to make it look similar to the positive above? Maybe give me a Capture One Preset that I could import and the see what you adjusted?
to a positive that looks somewhat similar to this:
https://dl.dropboxusercontent.com/u/46581632/result.jpg
I just can't get the capture one tools to work the way I expect them to. The tools that work fine on digital camera files just don't work for this file.
Especially, when I use white balance on the negative (before I inverted the colors using the "Levels" tool) it never shift the colors so that the picked point is a neutral gray (that's what white balance is supposed to do, right)? When I use the white balance tool on the light part of the wall in the background, there is still a color cast, even at the point where I picked the white balance. Shouldn't the background wall appear in light gray with no color? Could there be something wrong with the tiff file?
Can you give me a tip how to adjust the above negative to make it look similar to the positive above? Maybe give me a Capture One Preset that I could import and the see what you adjusted?
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If there's a color cast, maybe you could try to compensate for it with the Color Balance tool. 0 -
Almost 180MB! But I gave it a try.
I've done just a few negatives with CO yet. And I really like the results.
Does your scan really look like the negative? There's a heavy red color cast on it. So much, that even the lowest WB setting cannot fix it. There is a lot of difference between the channels, and the 'exposure' of your scan is about 3 stops off.
Regards,
Hans0 -
When you inverted the curves, did you do it RGB or Luma.
I had it in Luma and experienced the same problems you mentioned.
Changed it to RGB and things looked much better.
*Edit*
Though it looked better, there's something definitely wrong. I too got a nasty red cast. Kinda reminded me of an infrared image without the correct white balance.0 -
Hybrid, would you mind making a low res file available? Approx. 5MB should do the trick. Then several more of us would chime in with our knowhow. Thanks! 0 -
Yep, 180MB! 5MB would have been easier...
Here's how I used the Curves Tool:
http://www.smallguerilla.co.uk/c1_images/1-dog-rgb.png
http://www.smallguerilla.co.uk/c1_images/2-dog-luma.png
http://www.smallguerilla.co.uk/c1_images/3-dog-red.png
http://www.smallguerilla.co.uk/c1_images/4-dog-green.png
http://www.smallguerilla.co.uk/c1_images/5-dog-blue.png
Then some adjustments with the Color Balance Tool:
http://www.smallguerilla.co.uk/c1_images/6-dog-color-balance.png
And the final result, though could still use a little tweaking...
http://www.smallguerilla.co.uk/c1_images/7-dog-new-result.jpg0 -
Good job Bryce,
Hybrid, I have another way to do this with a similar result.
I use level instead of curve.
1) Because of your color cast, it's good to begin with the white balance adjustement. Just click on a white pixel with the tool. I found a good one on your dog 😄
http://www.bernard-boudon.com/temp/01.jpg
http://www.bernard-boudon.com/temp/02.jpg
2) For this step i correct all level as you can see below:
http://www.bernard-boudon.com/temp/03.jpg
3) Last setup with the level is easy: switch white and black point beginning to get a positive picture.
http://www.bernard-boudon.com/temp/04.jpg
4) You should make some corrections with the color balance tool to get the result of your dreams....
http://www.bernard-boudon.com/temp/05.jpg
My final result:
http://www.bernard-boudon.com/temp/06.jpg
Have a lot of fun with Capture One 😄0 -
Thank you all for your help and sorry for the 180MB. It works for me now and I learned a bunch.
So to invert the whole thing there seem to be two approaches inverting the RGB curve or inverting the RGB levels. I wonder what the effective difference between the two is. When should I prefer which?
It looks like some of the tools work on the original image (like the color correct picker, when I select pixels that now look red, it actually selects green pixels, or the HDR highlights and shadows sliders are inverted) and others work on the already modified image (like the color balance, when I drag into into the blue the image gets bluer not more yellow, when I drag the lightness slider of the color balance tool down, the image actually gets darker, not lighter). Why is that so. Is color balance aways applied after all other modifications? How can I learn in what order the modifications are applied and what modifications affect other modifications?0 -
As far as I am aware, there is no right or wrong here. The Curves and Levels tools are just different user interfaces for manipulating the relationship between input and output tonal values, whether in RGB mode or the individual color channels. So the choice is yours.
Sascha Erni, in his excellent book on C1, Capture One Pro 9 – Mastering Raw Development, Image Processing, and Asset Management, states it this way: The Levels tool is intended for placement of shadow, midtone, and highlight values, while the Curves tool modulates the shape of the tone curve which the Levels tool produces. See pages 133-139.
The Curves tool is obviously more powerful as one can use the eyedropper in both RGB and Luma mode to directly select specific tonal ranges, and then manipulate these as desired. And any density adjustments made in the Luma mode are (almost) color-neutral. The Levels tool doesn't have a Luma mode.
Whether using Levels or Curves (or both, if one so desires!), measuring color as one adjusts it, is critical. In doing so, the L*a*b* color model readout is by far the easiest to use, in my opinion. See my post:
"Missing CIE L*a*b* color readout – a real workaround"
viewtopic.php?f=61&t=24362
One thing is clear when working with negatives, much of C1's automation in regards to tone selection and manipulation, becomes counter-intuitive at best, or at worst, rendered useless. As an example, most color negative film has a strong orange cast, which, back in the days of the wet darkroom, allowed for the use of an orange safelight while making prints. If one uses the C1 White Balance tool on an area which in the final positive is know to be a neutral white or gray, the White Balance tool will render the entire image too blue as it attempts to neutralize the orange cast. The White Balance tool is not smart enough to know the context of working with a color negative where orange equals neutral.
From my understanding, the Cultural Heritage version of C1 has some additional functionality to aid the user when working with scanned negatives, possibly even a "smart" White Balance tool which can be set for the specific film stock at hand. I have never had the privilege of using the CH-version, but if I was responsible for scanning bucket loads of negatives, and the budget was high enough, it might be well worth the $4,000 price tag.
Short of owning the CH-version, the tools available in the normal C1 version can produce great results if used in the right way. Surely someone out there in C1-land has developed a good routine for working with B&W and color negative scans. If you're that person, perhaps you could share your process with us. It would be most appreciated!0 -
I've successfully implemented this raw workflow for a couple of clients with huge archives of trannies, colour & B&W negs. Swap C1 for LR and use the suggestions above. 0 -
I've successfully implemented this raw workflow...
Thanks for this workflow link, Robert.
The point about color correcting the light source to (mostly) eliminate the orange cast, and thereby gain some shadow latitude, was an eye-opener for me. Thank you!
In your implementation of this workflow, did you use SilverFast for color balancing your color negatives (as the Figure 14 video suggests), or were you able to produce high quality results in LR alone?
It would appear that the strength of using SilverFast is its built-in color tone profile curves for specific film stocks. Being able to tweak preexisting customized curves (basically like presets) seems like a real time saver, especially if the task at hand is color balancing many different color neg film stocks.
Are you aware of anyone who has created film-specific C1 presets for working with color neg scans? Maybe there's a market for this sort of thing. I would certainly be interested.0
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