Re: Experience with 20X24 format

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From: Sandy King (sanking@clemson.edu)
Date: 11/28/01-10:35:16 PM Z


Hi Neal,

I look forward to hearing more about your work with the 20X24.

Yes, I was very surprised that the 450mm Nikkor covered so well. It
even allowed some movement when focused at about 25 feet. The
diagonal of 20X24 is about 30 inches, so the Nikkor-M, which is
17.75" in focal length, is .58 of 30, so the correlation would be
more to a 20-21" lens than a 24".

I develop all of my large film (7X17, 12X20, and now 20X24) in print
drums with either Pyrocat-HD or ABC+ (Rollo Pyro) and have never had
any problems. I pre-soak most of the time (in the drum) for about 5
minutes but even on the times when I did not pre-soak I saw no
streaking or staining. I would avoid PMK, however, because in the
past I did see some streaking with PMK and rotary processing. The
film that I developed after the recent experience with the 20X24 was
FP4+. It was developed in a Jobo 20X24 print drum on a Unicolor motor
base with Pyrocat_HD and the negatives were perfect.

When processing in print drums I do follow an agitation method that I
would highly recommend. Once every 1-2 minutes, depending on time of
development lift the drum off the motor base and agitate vertically
for 10-15 minutes. If you don't do this you may get bromide drag from
the laminar flow of the developer.

Sandy King

>Dear Sandy,
>Your account has inspired me to borrow a friend's 20X24, for a project I've
>been working on, photographing squatter settlements in Manila. I also have a
>450mm Nikkor-M and was pleasantly surprised to hear that it covers the
>format! I am wondering how wide this lens ends up being on 20X24, something
>like a 24mm in 35mm?
>How did you process your film? I was thinking of using Rollo-pyro in a Jobo
>20X24 print drum, but am concerned about film streaks that I've heard occur
>with the big print drums. Given the high cost of the film and the fact that
>I only have one film holder, I don't want to lose film in the processing
>stage so I'm thinking the safer alternative is a regular non-staining
>developer that isn't so streak-sensitive. Its just that the pyro gives me
>such delicate tonality in the sky. Anyone's experience developing this
>format would be appreciated.
>Thanks in advance, Neal
>
>> From: Sandy King <sanking@clemson.edu>
>> Reply-To: alt-photo-process-l@skyway.usask.ca
>> Date: Mon, 26 Nov 2001 17:51:46 -0500
>> To: alt-photo-process-l@skyway.usask.ca
>> Subject: Experience with 20X24 format
>>
>> Hi folks,
>>
>> In this day of digital equipment I suspect that most of you will
>> consider that the use of a 20X24" format camera is "alternative"
>> photography. Which gives me justification to post the following
>> information.
>>
>> Yesterday, with the aid of Sam Wang, I took a real live 20X24" camera
>> into the field and made four negatives, using the FP4+ like film from
>> PhotoWarehouse. Sam's help was invaluable because the camera, which
>> is a home-made field camera after the Nagaoka, weighs about 50 pounds
>> and it can be something of a bear to get on the tripod. I was pleased
>> to find that my Manfrotto 3036 tripod and 3039 head, though not rated
>> for this weight, supported the camera very well.
>>
>> I used three lenses for the four negatives, including a 480mm Dagor
>> and a 450mm Nikkor-M and was really surprised to find out that the
>> Nikkor-M covered the format and even allowed for a bit of movement.
>>
>> The negatives were developed in Pyrocat-HD for 15 minutes, based on a
>> scene with a SBR of about 5. The only problem I had was a small light
>> leak caused by movement of the holders on re-insertion of the dark
>> slide after exposure. Actually, what I did was insert the slide
>> between the camera and holder, thus pushing the holder slightly out
>> and allowing light to pass. Silly thing to do but on the vertical the
>> top of the holder was a foot over the top of my head and the
>> insertion point thus not visible.
>>
>> Sandy King
>>
>>

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