Re: Digital Carbon Negatives

From: Sandy King ^lt;sanking@clemson.edu>
Date: 03/07/04-11:03:36 PM Z
Message-id: <a0602041abc71add9bf67@[192.168.1.100]>

Rjuj wrote:

>are using films that are less than ideal for
> > alternative printing because they have such a high rise in B+F from
>> the longer development times we must give them to get enough
>> contrast. Films like BPF and HP5+ are good examples. And of course,
>> as I noted above, an increase of 0.15 for a traditional negatives
>> becomes an effective increase of 0.30 to 0.45 for a stained negative.
>>
>> What to do?
>
>Why don't people use antifoggant like 1-phenyl-5-mercaptotetrazole or
>one of benzotriazoles? I suggest PMT in 3-10% of phenidone by weight,
>or benzotriazole in 50-100% (same) as a starting point. You can use
>KBr as well.

I don't know why people don't use antifoggants. Sounds like an idea
worth experimenting with, though.

But I have a question. I have some Benzotriazole. Suppose I make a
10% solution of Benzotriazole. As a starting point how many ml of
this 10% solution would you suggest adding per liter of working
developer if the goal is to cut B+F in half, say from log 0.50 to log
0.25.

Sandy

>
>> 4. If you must shoot films like BPF and HP5+ in very flat lighting I
>> would recommend that you either develop the film in a Pyro developer
>> that does not produce a lot of stain, ABC Pyro at the 1:1:1:7
>> dilution for example, or use a very high energy developer like Kodak
>> D19, which you will have to mix from scratch.
>
>If highest contrast is desired, D-11 is probably a better choice than
>D-19. You can still buy D-19 in a bag (at least last when I checked)
>but you have to mix D-11 from bulk chemicals. These developers contain
>KBr and fog increase with these developer should be pretty minimal.
>
>--
>Ryuji Suzuki
>"All the truth in the world adds up to one big lie." (Bob Dylan 2000)
Received on Sun Mar 7 23:04:20 2004

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