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If you look at 800% or so, you will probably discover that the magenta is actually a mixture of reddish and sometimes a bit of green pixels, mixed with the proper dark color pixels. Since you are scanning slide, the darkest parts will be very dense, and thus cause electronic "noise" pixels, which in my experience, generally turn up as these reddisch pixels...
Not much you can do about it, except getting a less "noisy" scanner with higher true DMax (which will be difficult as well at reasonable cost, you are quickly ending up in the Imacon / Drumscanning range).
By the way, the overall scan looks a bit to bleuish or cool in my eyes on my (calibrated) monitor, but lets wait what others with better monitors have to say.
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I did not come to think of that. Just to see what comes out, bellow is 100% crop from 2400 dpi scan. Yes, the scan is slightly blue, however such a cast would be easy to remove. I did not adjust the scan before posting.
I understood that it should be possible with this scanner to make a scan with higher exposure (and blowing out the highlights). Doing such a thing could yield better shadow quality. I could merge two scans later. Now I need how to figure out how to do that. I guess just a simple multi scan would not solve much here.
However - I have seen some scans from Guy Tal with this scanner and he did not seem to have these issues ...
Unadjusted:
The same crop with levels pushed to 2.0 to see the noise in the scan:
Seems like your theory is correct.
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Hi
feel silly suggesting this as I don't have one .. but ....
try examining something like a stouffer stepwedge in the darker scales. apply curves to the resulting scans to see if the responce of R G and B is even. Split channels and look for differing noise ... I find that with some scanners you need to roll off the lower end to avoid noise with curves thus sort of obviating the extra step or so they get in claimed Dmax
For instance I found quite horrid results in my LS-4000 which woke me up to the reality of things a little (after having been dreaming of one for ages). I carefully cleaned the optics and paths in this scanner and these are the after scans.
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Pellicle is correct, but you don't need a stouffer wedge. You only need to look at each individual channel of your current scan to see if there is more noise in one channel over another. The best place to look is in an area where there is empty shadow.
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OK, so I understand that you use the levels adjustment to suppress the lowest values. This approach would give smoother black parts of the scan. But this does not really solves the problem. Adjusting each color level separately usually leads to color shifts, though I would have to try this one first.
I am still looking for the exposure (hardware) adjustment in the SilverFast. The only one I found up to now is software based and this has no effect on the noise and cast problems. Hmm ...
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Matus
you'll notice that I only adjusted the lower levels, then returned the scan to linear quickly. I find that colour shifts are less obtrusive in the shadows where blue will be too high anyway in outdoor situations ... then there is the reality that in the shadows there will be all manner of reflected colour temperatures anyway mucking it all up.
did you notice any colour shift in my returned sample? It had a white area too
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OK, I played a bit more and did the scan with 4 following settings:
- no noise reduction of any kind
- gamma of 2.0
- 1200 dpi (to make the handling of files in PS faster)
A) 48 bit, auto adjustments (color, curves, etc..)
B) HDR 48 bit (no color, levels or curves adjustments possible with HDR setting)
C) MultiExposure (ME) - with ato color, curves and leves. In this setting the scanner takes two scans with different exposure settings and merges them
D) HDR + ME (again, no curves, leves or color adjustments)
after the scans were made all scans had "global" levels adjusted to cut away empty regions (very different in the 4 cases - (A) needed basically no level adjustment) and then some color balance adjustment. With these very basic processing I was able to get rather reasonable result with (B) and (D), and not that good with (C), the worst being the (A). Indeed - one can play more and I believe that using techniques mentioned before would allow cleaner work. I will be trying them once I master a bit more the scanner itself.
From the noise point I got the best looking shadows with the mode (D). (A) displayed ugly dark areas - separated from the rest of the image.
Concerning the shadow detail the (D) yielded the best results. While the amount of shadow detail captured by (D) when compared to (A) was not better by a large margin, it was blending into detail less areas in a much more smoother way. Caveat here - I was looking in a out of focus areas. I will have a look at this issue with some other slide.
So - I consider this issue more less solved. I still hope to get the answer from SilverFast as there do not seem to be many users of the F1/M1 around.
Thank you for your help - I will keep you updated about this scanner and its capabilities.
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