Alan, I suspect that your negatives have aged and the colour cast you're seeing is also inconsistent across the image.
Just for grins I downloaded that image and tried two correction methods in Photoshop. One technique is really simple and quick but is meant for more subtle casts and seems to subdue the midtone contrast in your image. It involves compositing an image with a solid colour created with the Average filter then inverting it, and blended using the Color blending mode at a low opacity. 25% opacity looked about right to me. http://www.candidcass.com/quickly-easily-correct-color-casts-using-photoshop/ The other technique involves separately adjusting the RGB curves to reduce the cast. It's much more subjective and hit-or-miss, depending on your ability to eyeball the cast and also to know some colour theory (which I'm weak on). You can see three images here: original, negative-average, and RGB curves. https://www.dropbox.com/sh/3n1cel5jz3fxw96/AAC2Ju1FNDxE-wOm-1qGloXqa?dl=0 The negative average de-cast looks the most accurate to me but seems to subdue the colours. The RGB curves probably need more tweaking because now I think there's a magenta cast, but the colour seems more vibrant. On Sun, Mar 5, 2017 at 8:59 AM, Alan C <[email protected]> wrote: > I picked up a slide copying attachment for my old M42 bellows with a view to > copying all my slides & negatives. I know you guys all use Epson scanners > but they are very expensive here. I set it up with a Super Tak 55/2 which > gives about 90% coverage. 65mm is needed to get 100%. (Unfortunately I > cannot use my K-mount lenses unless I replace the M42 flange with a K-mount > one). Anyway, it works fine and as I would probably crop most of them, 90% > is OK. Colour rendition & sharpness are good. Slides, no problem. However, I > am getting yellow colour casts on the sky with negatives after inversion. > Using an 80B filter on the lens or using the filters in Elements gives more > or less the same result. Shooting RAW or JPEG makes little difference but > shooting RAW allows me to batch process very easily. I used the sky for > illumination. I can easily process 50/hour. Example: > > https://www.flickr.com/photos/wisselstroom/33222112546/ > > Any ideas on getting rid of the colour cast? > > Alan C > > --- > This email has been checked for viruses by Avast antivirus software. > https://www.avast.com/antivirus > > > -- > PDML Pentax-Discuss Mail List > [email protected] > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and > follow the directions. -- -bmw -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
