[alt-photo] Re: Creating Film Negative by Enlarging a Film/ Slide Positive

[Dave S (fotodave)]

Francesco,

Tri-X is good for your original. It has a flatter curve on the highlight
area (I am talking about negative here, so the highlight of the scene, or
the dark area of the negative). If exposed and developed properly, one has a
nice highlight (the Ansel Adam look). When Kodak came out with TMax, many
photographers are not used to it because they use the same zone system
calibration but found that with TMax they lost highlights. That is because
TMax has  a straight characteristic curve.

But Tri-X might not be a good choice for interpositive. As you know, Tri-X
has pronounced grains, so if you use Tri-X for originals and then Tri-X for
interpositives and the final negatives, you will have some cross grain
problem (sort of similar in concept with Moire pattern except this is
random).

If you like the look of Tri-X, I think you can have good result with Tri-X
original, TMax interpositive, lith film for final negative (as it is
cheaper).

As for contact or enlargement, if you are after impressionistic look, then
it probably doesn't matter. If you want the sharpest and most accurate
duplication, the best result could be obtained by enlarging interpositive to
final size, then contact printing the final negative. The next would be
contact printing the interpositive and then enlarging the final negative.
Still next would be enlarging the interpositive (to an intermediate size, e.
g. from 35mm to 4x5), then enlarging again to the final negative size.
Though people describe the last one as losing too much sharpness, I have
done it quite successfully (at least I was happy about the result).

For the exposure, if your original negatives are all nicely callibrated,
exposed and developed, maybe you can use the simple exposure as you
mentioned. Otherwise you will have determine the exposure time by each
negative. You can use a densitometer or an exposure meter to determine the
exposure. The important thing is not to lose any highlight or shadow in the
interpositive because once it is lost, you cannot recover it in the
subsequent steps.

Dave


-----Original Message-----
From: alt-photo-process-list-bounces at lists.altphotolist.org
[mailto:alt-photo-process-list-bounces at lists.altphotolist.org] On Behalf Of
Francesco Fragomeni
Sent: Sunday, June 03, 2012 6:38 PM
To: The alternative photographic processes mailing list
Subject: [alt-photo] Re: Creating Film Negative by Enlarging a Film/ Slide
Positive

Dave,
Most of the instructions I've found list TMAX 100 and 400 as good films for
reversal. What about Tri-X? Does it work as well? I've always loved Tri-X
for 35mm and have quite a lot of it so if it works with this film that saves
me some money and waste. Let me know your thoughts. Also, I've always been a
B&W shooter so I'm not working with slide film at the moment, i was just
considering the switch for this particular purpose although reversal seems
like it might just be easier (and less expensive). When you refer to
negative-positive-negative approach do you mean making regular negs in
camera and then contact printing them to positive and then finally enlarging
the interpositives to larger film negatives? I've entertained this idea as
well and would be interested in hearing more on the topic. I figure I would
cut up a developed roll and lay the strips out on an 8x10 sheet of film like
making a contact sheet and expose the whole roll at once and then develop
the 8x10 sheet after which I'll have my positives that can be cut and
enlarged onto bigger film. Is this how you'd go about it?

Also, is there a best way to approach exposure in the enlarger/ light source
when contact printing the negs to produce positives and then the subsequent
enlargement to big film negatives? I was told it was as simple as laying a
grey card in the film plane (on top of contact printing frame for neg to pos
phase and under the enlarger lens for the enlargement phase) and taking a
meter reading at the iso of the film and then stop down and expose. Is this
correct? Seems quite simple if this is the case.


Geoff,
I too have used 8x10 primarily. I actually just stepped up to 11x14 and
8x20. I love big cameras and big film but I also love my 35mm Leica lenses
and very much still enjoy shooting 35mm. However, I am a contact printer and
prefer to work with the contact printing workflow far more then enlarging
and on top of that the materials I use require contact printing in almost
every case. So, I've set out to figure out how to enlarge these 35mm negs of
mine :)

Would you mind sharing your reversal process as well? I'd be interested to
hear it.

I'm familiar with the copy-print process but in this case it not the method
I'd like to use. Also, the waxed paper techniques are something I'm very
familiar with. I spent a long time working exclusively with paper negative
processes. Great stuff but not ideal for my purposes here.


Thanks for the insight everyone, I look forward to reading your responses
and further comments!


Anyone else listening,
bellow are a few links to reversal process explanations and instructions
that I'm looking at:

http://www.angelfire.com/wi/spqrspqr/photo/bwreversal.html
http://www.bonavolta.ch/hobby/en/photo/slidesbw.htm
http://www.digitaltruth.com/products/formulary_tech/01-0600.pdf
http://www.bonavolta.ch/hobby/files/Kodak%20j-1.pdf

-Francesco



On Sun, Jun 3, 2012 at 3:04 PM, Geoff Chaplin <geoff at geoffgallery.net>wrote:

> Well here's my two pennyworth.
>
> I generally used in camera 8x10 negs but over the last couple of years
> have enlarged 35mm up to 16x24 for gum printing. I've tried the
> following
> methods:
> A. Reverse process B&W file (easy but lengthy) and print onto (e.g.
> FP4+) film.
> B. Neg -> enlarged print -> contact print onto (film, lith film,
> paper)
>
> Out of the second set of steps printing onto paper is easiest but has
> a limited tonal range and leads to slow printing times. This can be
> speeded-up a bit if you print onto fibre based paper then oil the back
> (any clearish oil will do. Printing onto film is OK but I find
> difficult to judge - a densitometer helps. Generally I print onto lith
> film partly because it's cheap and robust. But the downside is
> development and resulting contrast range. I think I've tried
> everything that’s suggested on APUG and elsewhere and find the best
> continuous tone developer is dilute paper developer about
> 1/4 strength. It oxidises very quickly so you need a fresh batch every
> half-hour or so. Sometimes its necessary to make two negs - highlights
> and lowlights.
>
> Of course scanning an digi-printing as a million times easier ....
>
> Geoff Chaplin
> チャップリン・ジェフ
>
> geoff at geoffgallery.net
> www.geoffgallery.net
>
> Skype: geoffchaplin1611
> UK mobile (英国の携帯電話): +44(0) 7770 787069 Japan mobile (日本の携帯電
話): +81(0)
> 90 6440 7037 Japan land line / fax (日本の電話とファクス): +81(0) 166 92
5855
>
> -----Original Message-----
> From: alt-photo-process-list-bounces at lists.altphotolist.org
> [mailto:alt-photo-process-list-bounces at lists.altphotolist.org] On
> Behalf Of Francesco Fragomeni
> Sent: Monday, June 04, 2012 1:11 AM
> To: The alternative photographic processes mailing list
> Subject: [alt-photo] Creating Film Negative by Enlarging a Film/ Slide
> Positive
>
> I'm interested in enlarging positive film (any slide/ chrome film or
> B&W reversal processed film) onto a larger piece of traditional B&W
> negative film (not lith) for the purpose of producing enlarged
> negatives suitable for alt-process and Azo. I know people do this but
> I've had a difficult time finding a solid explanation and instructions
> for how to go about it since it is far more common to scan these days
> which I am very aware of but not interested in with this particular
> case.
>
> Basically, can I expose/ enlarge slide (positive) film onto regular
> B&W negative film and achieve an enlarged negative? Is the higher
> contrast of slide film helpful in this situation or a hinderance?
> Would it be better to contact print B&W negative film (much lower
> contrast) onto another piece of B&W neg film to produce a positive,
> develop to the same contrast as the original, and then enlarge that
> lower contrast film-interpositive onto a larger sheet of B&W neg film to
achieve the enlarged negative?
>
> I'm interested in this specific process of enlarging film positives to
> larger negatives, not the alternatives so lets please try to stay on
> topic and not go astray with conversations of digital negatives,
> duplicating film, etc., although if reversal processing your original
> B&W neg to positive plays a role that might be worth explaining.
>
> Thank you!!
>
> -Francesco Fragomeni
> www.francescofragomeni.com
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