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Re: [OM] Got a new (OT) squeeze; my poor pooch

Subject: Re: [OM] Got a new (OT) squeeze; my poor pooch
From: Moose <olymoose@xxxxxxxxx>
Date: Tue, 19 Jun 2012 22:24:26 -0700
On 6/18/2012 10:02 AM, Joel Wilcox wrote:
> I recently picked up a beautiful Mamiya RB67 Pro-S with two useful "C"
> lenses, the 90 and the 250.

Congrats!

> A couple test rolls of Portra and Ektar
> await processing, but I was able to soup a roll of Fomapan 100 this
> weekend.  Eight minutes in Rodie 1+50.  My bottle of Rodinal is
> hilariously old and a retching brown, but as it is all I had, it had to
> do, and it did pretty well.  I scanned and put my favorite of the lot on
> my homepage:
>
> http://myweb.uiowa.edu/jfwilcox
>
>
> I was happy with the film and exposure for holding the highlights.
> Other than that, I am still working on the amount of shadow detail I
> want.  This issue is somewhat an aesthetic one with regard to this
> photo, but it is a larger concern as I figure out what the standard
> profile needs to be for this film/developer combo in Vuescan.

In the stairs image, it seems to me the shadows are blocked up and the 
highlights a little too compressed. Also, 
assuming it is as it looks, a bright, sunny, midsummer's day, the shadows of 
the foliage on the stairs and the building 
on itself don't seem to be contrasty enough. 
<http://www.moosemystic.net/Gallery/Others/Wilcox/old-cap-stairsw.htm>

The building image needs these things less, but I did much the same thing to 
it, to show what it would do. 
<http://www.moosemystic.net/Gallery/Others/Wilcox/old-cap-1-w.htm>

> For anyone familiar with scanning BW in Vuescan, I initially scanned all
> frames selecting "Generic" as the film type, since there is no film type
> available for Fomapan.  I had to adjust the curve to bring up the middle
> values quite a bit.  With some experimentation I found I liked one of
> the various TMAX 100 profiles a little better from the outset.  That's
> fine as far as it goes, but it feels like a pig in a poke to proceed in
> this way.  In the end I guess it always is.

Vuescan uses standard ICC color profiles. I suppose there might be some B&W 
profiles out there, although I'm not sure 
how that might work. IT8 profiling works by comparing scan values for the color 
patches to absolute numbers I suppose it 
may first brightness correct the whole thing using the B&W steps? I can't at 
the moment imagine how to use that for B&W

And you might try Ed again on B&W profiling. The renaissance in B&W film work 
may have put more pressure on him in the 
meantime. If anyone could figure out a way to create B&W profiles using just 
the B&W steps on the IT8 target, I'd think 
he would be the one. I don't know if they could be standard ICC format, though.

If it's close to being a gamma problem, one could make custom PS color settings 
with different gammas and find one you 
like for a particular film. If you use VueScan's RAW output option, you can 
then apply any gamma you want to the image 
in PS.

> I don't see why there would be any point in scanning in 16bit rather
> than 8bit if doing BW, so I don't see why the option is available, or
> why anyone would scan BW in RGB mode, which is also apparently possible.

You are conflating bit depth with color. There is exactly the same reason to 
work in 16 bit in B&W as in color.

8 bit B&W allows 256 grey tones for use in the image. 16 bit allows 65536 
separate tones. 256 is fine for a perfectly 
exposed and profiled image, for both printing and web. But as soon as one 
starts bending bits in an editor, 256 bits 
becomes inadequate, and funny things begin to happen, as alterations clump and 
spread tones.

Every once in a while, I am working with an 8 bit image, and things aren't 
working quite as expected. Then I notice why, 
and have to go back, convert to 16 and redo at least part of the work. I've 
found no reliable way to know on which 
images or at what stage of work the oddness may occur, so I just work in 16 bit.

An 8 bit color image is 24 bit, 8 for each color channel, 16 bits per channel 
is 48 bits total.

Multi Bit Moose

-- 
What if the Hokey Pokey *IS* what it's all about?


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