DK-50 is not a particularly contrasty developer. D-19 was
originally designed for X-Ray film and is quite contrasty.
However, one can find much more contrasty developer for photo
mechanical work like Kodak D-8 and D-11. I have no idea if these
are suitable. I don't remember what D-90 is, I though perhaps a
late motion picture positive developer. The usual routine for
motion pictures is to process the negatives to quite low contrast
and the prints to quite high contrast. There is a difference in
the negatives for sound; for variable density sound the negatives
are quite low contrast, on the order of the image negatives, for
variable width, AKA variable area, the negatives are very high
contrast. However, all B&W release prints are high contrast
regardless of the sound tracks.
On 10/17/2021 3:39 PM, BOB KISS (bobkiss) wrote:
DEAR JANET,
I don't presume to have "mastered" S0-132 but I have some suggestions.
1) Use the most contrasty developer you can find.I tried DK 50but too weak.Then D-19 and later another Kodak dev named D-90something that was supposed to be the most contrasty thing since Lith devs.
2) It seems to me that there is no such thing as over exposure!LOL!!!To get ANY areas thin enough to print as shadows you have to REALLY expose that stuff.
3) Don't be shy about using a bleach such as Farmer's Reducer (Potassium ferricyanide and sodium thiosulfate) to clean out those shadow areas.Of course, you have to do it JUST enough to allow the shadow areas to be thin enough to print but not so much that you lose texture (a.k.a. image info) in those shadows.
4) Be ready for looooooooooooooooong exposures for most alt processes.
I did some and they worked but, as soon as I learned to scan negs, image process the files, and print diginegs on my epson, I left the remaining SO-132 in my freezer.
CHEERS!
BOB
*From:*pure-silver-bounce@xxxxxxxxxxxxx [mailto:pure-silver-bounce@xxxxxxxxxxxxx] *On Behalf Of *janet ness
*Sent:* Sunday, October 17, 2021 5:09 PM
*To:* pure-silver@xxxxxxxxxxxxx
*Subject:* [pure-silver] Re: ISO 4 Direct Positive Orthochromatic filmI
I have several boxes of Kodak SO132 b&w duplicating film in my freezer. I tried to use it for enlarged negatives years ago, but much success (developed in Dektol). Has anyone mastered the process?
Janet Ness
-----------------------------------------------------------------
*From:*pure-silver-bounce@xxxxxxxxxxxxx <pure-silver-bounce@xxxxxxxxxxxxx> on behalf of MARK SAMPSON <dmarc-noreply@xxxxxxxxxxxxx>
*Sent:* Saturday, October 16, 2021 10:37 PM
*To:* pure-silver@xxxxxxxxxxxxx <pure-silver@xxxxxxxxxxxxx>
*Subject:* [pure-silver] Re: ISO 4 Direct Positive Orthochromatic film
There would have been several direct positive b/w films from Kodak over time. I remember using “High Speed Duplicating Film” on the job in about 1978. Despite its name it was the slowest of the many laboratory and graphic arts films we used then. I know there were others later on but the details escape me now… SO-015 comes to mind. Bob Shanebrook might have something to add here, and there may be a listing in his book; I don’t have access to a copy right now though.
Mark S
Sent from my iPhone
> On Oct 16, 2021, at 11:15 AM, `Richard Knoppow <dickburk@xxxxxxxxxxxxx> wrote:
>
> Lots of bells ringing. In fact, I think SO-239 is what was in my memory. It has been too long since I read the theory but I have a source for brushing up on it. You reminded me that Sabattier effect and solarazation are not the same. I think it is just too long since I thought about this so only rough outlines remained in my memory. I never actually forget anything.
>
>> On 10/16/2021 6:46 AM, BOB KISS (bobkiss) wrote:
>>
>> DEAR RICHARD,
>>
>> Yes, you are right.I have used Kodak SO-239 and X-Ray duplicating films (both direct positive films) to make enlargednegatives for printing on PT/PD and other alt processes...well before I learned to scan, image process, and print enlarged negs with my Epson.They use the phenomenon called solarization, (NOT to be confused with the Sabattier Effect, re-exposure during development, which is often improperly called solarization).The name came from the source of its discovery...black suns in images exposed for the landscapes.There was so much overexposure in the sun that it caused a reduction in density on the film yielding a darker or even black sun.
>>
>> At RIT we did some experimenting with various film/developer combos exposing the crap out of them through step wedges.You can clearly see the reduction in density with increased exposure in some combinations.(For those who care, it has to do with surface developers vs. internal developers because the excess exposure causes some of the released electrons to migrate into the interior of the ag-x xtal ergo, internal developers reduced the effect and surface developers increased it.)
>>
>> To make these films, they basically "flash" it up to the point where any further exposure will start decreasing density when processed in a surface dev.The film you mention here was probably made the same way.
>>
>> CHEERS!
>>
>> BOB
>>
>> -----Original Message-----
>> From: pure-silver-bounce@xxxxxxxxxxxxx [mailto:pure-silver-bounce@xxxxxxxxxxxxx <mailto:pure-silver-bounce@xxxxxxxxxxxxx>] On Behalf Of `Richard Knoppow
>> Sent: Friday, October 15, 2021 4:02 PM
>> To: pure-silver@xxxxxxxxxxxxx
>> Subject: [pure-silver] Re: ISO 4 Direct Positive Orthochromatic film
>>
>> My memory is not what it used to be so I don't remember
>>
>> details. You may know there is an effect where if an emulsion is
>>
>> seriously overexposed it reverses the image. This effect was used
>>
>> to make direct positive material. I am pretty sure Kodak and
>>
>> others made such films for either document copying or for making
>>
>> duplicate negatives or duplicate release prints where only the
>>
>> original positive was availabe (or from a reversal film). I am
>>
>> just drawing blanks on the name of the material or even the name
>>
>> of the effect it made use of. I am hoping someone else here has
>>
>> enough of a clue to remember. Meanwhile I will look at what
>>
>> documentation I have to get a reminder. ISO-4 is in the range of
>>
>> fast enlarging paper or positive films. If you developed a clip
>>
>> what did you get? If I am right it should have come out black and
>>
>> a clip exposed to strong light should come out clear.
>>
>> It is the term "direct positive" that leads me to think it
>>
>> might be this stuff. If, however, its just "positive" its
>>
>> probably something like Kodak Fine Grain Release Positive, a film
>>
>> originally intended to make release prints of B&W movies. This is
>>
>> a very slow film, ISO-4 would make sense for it, with an emulsion
>>
>> similar to fast printing paper like the late, lamented,
>>
>> Kodabromide. There is likely still data on it on line and similar
>>
>> film may still be made because it was also used to make masks (or
>>
>> matts) for motion picture special effects and titles. It can be
>>
>> processed in any fairly active developer like paper developer or
>>
>> D-19.
>>
>> On 10/15/2021 12:38 PM, Martin magid wrote:
>>
>> > I developed a strip, and there is nothing printed on the edges.
>>
>> >
>>
>> > Now what?
>>
>> >
>>
>> > Marty
>>
>> --
>>
>> Richard Knoppow
>>
>> dickburk@xxxxxxxxxxxxx
>>
>> WB6KBL
>>
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>>
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>>
>
> --
> Richard Knoppow
> dickburk@xxxxxxxxxxxxx
> WB6KBL
>
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