scanning colour negatives, how?
Posted: Thu Oct 07, 2010 10:06 am Etc/GMT-1+01:00
Updated: An overview of scanning colour negatives:
http://www.tristancampbell.co.uk/scanni ... -negatives
Yesterday it was suggested it would be good to see a thread where people show or explain how they process a colour negative. I know getting colour right is something that puts a lot of people off using colour negs which is a real shame as they are a wonderful medium to work with.
There are many ways of approaching it, usually people start with the built in scanner profiles or use plugins. Here is a rough and ready example of simply scanning the negative as a positive - just one of many techniques you can use.
The scan is from an Epson v750 and the image is taken on Pro160c.
Raw scan - colour negative scanned as a transparency. Make sure you are working with a 16 bit file to avoid losing data in the conversion and try not to clip the data either side of the histogram.
In curves bring the black and white points in to the edges of the image data in the graph - do this for each channel
same for green
and blue
now go back to the rgb view
drag the white point to the bottom and the black point to the top to invert the image
you're going by eye much more from now on. you always tend to end up with a cyan cast so the red channel usually needs most correction. I've clipped the data here for simplicity but ideally you probably want to add a few control point to avoid clipping.
no change to green here
highlights need more yellow so pull black point up a little
done. may not be accurate but it matches my memory of the scene quite well - a brief but pleasantly colourful sunrise on a rather cold and wet September morning. Maybe this is a bad example, and an example with skin tones or a scene without strong colour cast would have been better.
Would be interested to see how other approach the problem.
Tristan
http://www.tristancampbell.co.uk/scanni ... -negatives
Yesterday it was suggested it would be good to see a thread where people show or explain how they process a colour negative. I know getting colour right is something that puts a lot of people off using colour negs which is a real shame as they are a wonderful medium to work with.
There are many ways of approaching it, usually people start with the built in scanner profiles or use plugins. Here is a rough and ready example of simply scanning the negative as a positive - just one of many techniques you can use.
The scan is from an Epson v750 and the image is taken on Pro160c.
Raw scan - colour negative scanned as a transparency. Make sure you are working with a 16 bit file to avoid losing data in the conversion and try not to clip the data either side of the histogram.
In curves bring the black and white points in to the edges of the image data in the graph - do this for each channel
same for green
and blue
now go back to the rgb view
drag the white point to the bottom and the black point to the top to invert the image
you're going by eye much more from now on. you always tend to end up with a cyan cast so the red channel usually needs most correction. I've clipped the data here for simplicity but ideally you probably want to add a few control point to avoid clipping.
no change to green here
highlights need more yellow so pull black point up a little
done. may not be accurate but it matches my memory of the scene quite well - a brief but pleasantly colourful sunrise on a rather cold and wet September morning. Maybe this is a bad example, and an example with skin tones or a scene without strong colour cast would have been better.
Would be interested to see how other approach the problem.
Tristan
. Thanks for the comments.