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View Full Version : More plate madness - using Holography plates?



Ole
08-11-2006, 09:02 AM
I've just got hold of three dozen 4x5" holography plates, Agfa-Gevaert Holotest 10E75.

Now I don't really want to start with holography. Old plate cameras are "madness" enough!

So does anyone know if, and how, these can be used for photography? I assume they are very slow and very high contrast, but I also assume this can be remedied with appropriate processing.

BTW, they'll be used two at a time in a Linhof Universal 4x5" film and plate holder, most likely in a Speed Graphic, and vrey likely with an assortment of strange old (barrel) lenses.

MenacingTourist
08-11-2006, 11:13 AM
You're sick Ole, sick sick sick.

Dan Fromm
08-11-2006, 12:18 PM
You're sick Ole, sick sick sick.Wrong! Ole's not sick, he's clever.

Ole
08-11-2006, 12:22 PM
Wrong! Ole's not sick, he's clever.
You think there's a difference? :D

Dan Fromm
08-11-2006, 04:55 PM
You think there's a difference? :DAbsolutely! They're very different. Understand, though, that being clever doesn't preclude being sick too. And becoming sick doesn't induce cleverness in the naturally dull.

Cheers,

Dan

DBP
08-11-2006, 05:49 PM
I've long wondered the same thing.

Jerevan
08-12-2006, 12:17 PM
I don't know much but... there seems to be several types, with both blue, green, red and pancro sensitive emulsions. I can't see why they wouldn't be able to be used as normal plates as they seem to have a daylight spectrum sensitivity. The developer I found looks rather like a normal B/W developer to a non-chemist: http://www.holokits.com/jd-2_holography_developer.htm. Why not give it a go if you have a bunch of the plates lying around.

Be our expert guinea pig and report back of your experiences at the mountains of madness. ;)

David A. Goldfarb
08-12-2006, 12:25 PM
My impression is that the ortho and panchromatic plates are the same sorts of emulsions used for ortho and panchromatic films and plates designed for pictorial use, and that conversely ordinary films and plates can be used for holography.

Justin Cormack
08-15-2006, 05:13 PM
I think they will just be very fine grain and slow - to get the holographic effect you need resolution of the order of the wavelength of light. They might not be very contrasty necessarily. I did a very short course once but it was very many years ago and i forget. Seem to remember using a red laser, which would be the cheapest option, so presumably most are red sensitive.

Ole
08-17-2006, 01:06 AM
By searching around holography sites, I've learned that the plates are red-sensitive (almost into short IR!) and almost green-blind. So DBI looks like the way to go.

They also resolve 3000 lppm, although no lens can produce that resolution. But the resolution has to be around the wavelength of light for holography, so that shouldn't have been a surprise to me (600nm = 0.6 micrometer = 6/10000 mm, or 1666 lpm, 3333 lppm).

Justin Cormack
08-17-2006, 06:52 PM
They seem to be available in several sensitivities, not just red, but I think red is most common due to the red laser situation. Get your green safelight out.

Do Slavich still cut to size? Stories on the web say retrophographic used to sell them, though not sure if they still do.

You have the useful advantage of having plate cameras in every size which helps... trying to stick to one (or maybe two - being tempted) for now.

Kino
08-17-2006, 08:45 PM
You think you are sick; I got a bunch of Kodak 3 x 3 glass plates used in the semi-conductor industry for making substrate matrices; those have got to have a "curve" flat as plate glass and almost vertical!

Build a pinhole camera... learn to reverse process.. bwahh ha ha ha!

Ole
08-18-2006, 01:17 AM
They seem to be available in several sensitivities, not just red, but I think red is most common due to the red laser situation. Get your green safelight out.

Do Slavich still cut to size? Stories on the web say retrophographic used to sell them, though not sure if they still do.

You have the useful advantage of having plate cameras in every size which helps... trying to stick to one (or maybe two - being tempted) for now.

You're right, AFAIK there are several different emulsions with sensitivity in different ranges for different laser wavelengths. Mine are red-sensitized and have a very low green-sensitivity. Green safelight's the thing.

Slavich seems to be the last remaining plate maker, and they still cut to size. Unfortunately the minimum order weighs about a ton (glass is heavy!).

Retrophotographic still sells them, at least they still had a little stock of 9x12cm plates last time I looked. I've bought two packs from them, and still have one left. It's fun, but expensive fun!

As to plate camera sizes, there's a very useful little trick: My 24x30cm plate camera came with two complete sets of format reducing inserts: 24x30cm to 18x24cm, 13x18cm, 10x15cm, 9x12cm and 6.5x9cm. It may seem a bit difficult to shoot 6.5x9cm plates in a 24x30cm camera, until you realise that the camera has a minimum bellows extension of 30mm. Yes, 3cm. Maximum is about 120cm! Since the front movements (rise, fall and shift) don't use the bellows, there's sufficient movements to move the center of a 90mm lens completely outside a 5x7" (or 13x18cm) negative.

Justin Cormack
08-18-2006, 04:17 AM
Actually doing the measurements, 9x12 fits vertically in my (half plate) holders, and that must have been what was being used as the original ground glass is missing and someone has bodged a vertical one in the middle (I think it spent some time being used as a portrait camera at a guess). So I do have a two format camera without any adaptors! Might see if retro have any left then.

Hmm, they do have some left. I see what you mean about pricey though - 5 a shot. ISO 125 though - whats the spectral sensitivity of these ones? What do you dev them in? Have you got any example shots?

Pretty much ready to shoot now, see about the light leaks.

cullah
09-16-2006, 06:54 PM
I once used a Kodak product that was used for holography and astrophotography. Its speed was in the order of ISO .00000001. While using it to make photos of stars, with a normal exposure of 8 hours, it ended up being a faster film than Tri-x, due to reciprocity effects. It was as grainless as film could be. I shot some high-key scenes at noon with it and my time was in the 30 to 40 minute range. It was developed in D-19.

htmlguru4242
09-16-2006, 11:43 PM
I, too, have wondered this for a long time.

It seems to me that any light-sensitive silver halide material can be used for regular photography, even if its through some weird processing procedure.

The plates are (obviously) super fine-grain, and are slow.

I used some of the red-sensitive slavich plates once, playing around with holography with laser pointers (actually quite fun).

After a 30 second exposure about 8 inches from a laser pointer with the collimating lens removed, and 10 seconds in the developer, the plate was completely black, so they're not too slow ... I've always been wanting to try this.

Let us know how it comes out.