Thanks to all for their advice. I've never tried a Vuescan raw scan or
a positive scan, so I'll be giving those a try. Already, Vuescan is giving
me a nice flat scan that I can tweak.
Me'thinks I'll be delving deeper into the myriad options Vuescan's provides
from here on out.
Now I've also got to get some settings together to get a decent *batch*
scan
set of results (not all so flat) on FP4+ for initial quick digital
contact sheet
style results.
Scott
[EMAIL PROTECTED] wrote:
I've got the Kodak kit to do positives from BW film, but I haven't got
around to using it. I'd like to try the set on Macophot 820C, which is a
very fine grain extended red film.
Vuescan has a raw option. By raw, I mean really raw, i.e .no
correction what so ever. I'd suggest doing a raw scan and then see if
the blown highlights show up.
Vuescan has a control to set the white clipping point. I'm not sure how
vuescan sets it, but so the theory goes you should allow a small
percentage of the pixels to be clipped on the high end. This is because
often some specular highlight ends up setting the high end of the
display, making most of the image too dark. I like to photograph
aircraft, and this option just plain doesn't work well since shiny
subjects can have many specular highlights. I set this option to zero.
Going back to the raw mode, if your highlight are not blown, you could
try something like this.
1) Do a raw scan, saving in grayscale 16 bit. I think the default for
this is a positive image. If so, then invert it immediately after you
load it into photoshop
2) In photoshop, go to the adjust levels menu
3) Set the gamma to 6 (middle text box), making the image look very white
4) slide the leftmost slider to the right until you start to see black
specs in the display. This is setting the black clip point.
5) Set the gamma to 0.1
6) move the right slider to the left until the white specs are at an
acceptable level. This is setting the white clipping point.
7) move the middle slider until the image is acceptable. For a bell
shaped curve, this is generally at the peak of the distribution.
Acros and Astia (color slide film) are low acutance films. The images
don't look very sharp, but they are. I didn't like this low acutance at
first, but now I think it is more realistic.
You have discovered (rediscovered) what people call grain enlargement.
When you take a high latitude film and adjust the contrast to look
natural, the grain gets enhanced. This is why I prefer to do slide film.
It may be harder to scan, but you need to adjust the endpoints much
less, so the grain doesn't get magnified.
[EMAIL PROTECTED] wrote:
Yes, I actually have purchased a license for Vuescan and
haven't given it enough attention, still using NikonScan and
the Coolscan V for most of my work.
I develop my own BW negs and then scan them (no darkroom).
I shoot mostly HP5+ and FP4+, with occasional TMZ. I dev almost
exclusively with HC110 (B) and recently (H). I try to develop for a
low contrast, thinner negative to please the scanner, and have achieved
pretty good results with HP5 in dilution (H) at both 320 and 800 ISO.
But I have some problems.
(1) I haven't been so lucky with FP4+, where the highlights are blown
routinely even with extrememly conservative development, as in
HC110 dilution H at only 8 minutes. I did some film speed tests
per Les McLean's book. Black cardboard, white cardboard, lots
of cloth, metal, glass stuff on top. Meter with an incident meter and
then shoot +2, +1, +0, -1, -2 stops for a whole 35mm roll. Cut into
three strips and develop different ways.
The coolscan barfed on the highlights (white cardboard) every time
except for the -2 stop exposures. But then the shadow detail was
unacceptible, as you can imagine.
I want to use slower films to support some larger enlargements. I'm
about to start experimenting with Delta 100 and Fuji Acros, but these
seem to have even less forgiving contrast curves than FP4+ from
what I read.
I've been trying to tweak analog gain, but this is limited, because big
tweaks increase grain appearance, which negates the whole point of
using slower film in the first place.
(2) I often get what look like weird bright reflections off the grain. Not
in highlight areas. It's like bright specs, visible at 1:1 mag. This
stuff really
makes its appearance known during USM. I wonder if this is due to the
Coolscan's LCD light source? don't know.
(3) As I experiment and futz, I wonder exactly what Nikon's auto-exposure
is doing to the raw scan results. I can't find any documentation. In my
film
speed scans, I can see that AE is trying to control the highlights, but
I don't
know how AE is doing this. Is it *only* the equivalent of a curve adjustment
that I could make myself, or is it adjusting the analog gain or maybe doing
something else? Any input here would be greatly appreciated.
Anyway, howdy to the list from a new member. I do need to experiment with
scanning BW film as a positive
