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View Full Version : Magic Lanterns in the 21st Century / 8x10 Slides!



Ed K.
5-Aug-2007, 22:59
Sorry - there is no category on this forum for large format slide projectors...:rolleyes:

A few experiments over this last year with DR5 have produced some really amazing range and tonal qualities using 8x10 black and white film processed as a positive. While I have just sent a few tests, I can see that the slides from DR5 surpass anything that a scanner can scan or a piece of paper can hold. I want to do a photo essay in DR5 for its buttery smooth mid tones and deep shadow details... but somehow, there has to be a way to share the view of the slide on a larger scale. While the photos I shot for DR5 tests have been nothing to write home about, the tone and range simply floor me - it's an amazing process. Of course, I never used Scala - but it's the same concept. In particular, my upcoming project will match perfectly with the Van Dyke Brown tonal feel of HP5 processed in DR's #2 developer.

Part of my essay will have a series of backlit panels, masked, with original size slides suspended as part of a walk-through exhibit.

But I want a way to project some of the 8x10 slides using modern optics and I don't mind building a projector and carrier system to get it done. I think that a nice 8x10 foot projected image, changing every few moments would do the trick even if it takes two or three rigs to do the trick. At least then people could see what's in the 8x10 film image and experience its luminous qualities. Sure - scanning and then projecting, or using perhaps 120 film in DR5 would work fine, but I wish to use 8x10 for this project because it is the unaltered piece of film that was in the camera at the time of exposure. I also want the dynamic range that the film itself has without any digital intervention, banding or artifacts whatsoever.

I want one part of the exhibit to be personal and up-close, but then have a larger area that is more immersive, with some huge but pristine B&W images.

Has anyone here built or found a modern 8x10 projection system? Got any ideas as to which lenses could handle the job without killing my pocket book too badly? I wonder if heat absorbing glass and perhaps an active cooling system would allow at least 20 seconds display of an image?

I'm planning this project, and I may need to apply for a grant to assist me in creating the show. I don't have any of the images yet, so there is plenty of time - I'll be shooting this project in the upcoming fall through spring. But my proposal needs to have the whole thing worked out in advance somewhat.

Any thoughts appreciated.

Sandeha
6-Aug-2007, 00:30
Just imagining how it might look ... surely you'll only get those "luminous qualities" back-lit with a lightbox set-up. Projecting would degrade the image and the luminance, no?

So I imagine.

Wimpler
6-Aug-2007, 03:00
http://www.largeformatphotography.info/forum/showthread.php?t=26684&highlight=splendon

I posted there about the rodenstock splendar/splendon lenses. I own a 200mm/250mm and 300mm lens. I know the 300mm covers 5x7, don't know about 8x10, don't have an 8x10 camera :s

Here is a link about a 600mm rodenstock splendon, that should cover 8x10. http://www.bubu.jp/rodens600/rodens.htm

And an other page with special lenses (from episcopes, ...) http://alag3.mfa.kfki.hu/astro/GiantLenses/127mm.htm

Good luck.

Wimpler
6-Aug-2007, 03:01
more info on large format projectors: http://www.a1.nl/phomepag/markerink/proj_667.htm

BrianShaw
6-Aug-2007, 08:08
What an interesting concept - projecting LF slides. I have never given it much thought. Good luck to you!

I've found that showing folks LF (4x5 in my situation) transparencies has always evoked a "wow" response. I can only imagine what the "WOW" response sounds like for 8x10 transparencies.

With 35mm slides I recall a lot of film popping and hyperactive autofocus on the part of the old Carousel projectors. I'd expect this to be even a biger problem with LF projection. Perhaps there is a newer light source, like LED, that runs cooler and will make LF slide projector more practical.

David A. Goldfarb
6-Aug-2007, 08:35
Projection lenses are often quite simple Petzval designs. Maybe you could salvage something from an opaque projector or overhead projector for your purposes.

I've experimented a bit with a Beseler Slide King for projecting 6x7 slides, and the projected image is very impressive, even at that format. The maximum size is lantern format, but there were carriers for smaller sizes. I think ultimately I'll have some custom cardboard mounts made, lantern size on the outside with horizontal and vertical windows for 6x7, since the lantern slides only fit the carrier in the horizontal format.

Slide Kings are cheap, compared to modern medium format projectors, so the idea of having custom mounts cut becomes a very viable option.

Ed K.
6-Aug-2007, 15:09
Interesting collection of stuff on the links.

Overhead projectors usually have a mirror, a fresnel lens, and inexpensive optics - chromatic aberration? They also have a lot of stray light. There must be some good ones though.

I thought it might be possible to build a cooled (perhaps even refrigerated) light house, and then perhaps create a sliding carrier to hold glass sandwiched slides vertically. Then put the whole thing in a separate room. Who knows, perhaps I could rent a theater to accomplish this and then get some other photographers to coop the show with me. There are many small towns that still have theaters for rent - their projection rooms might do well, plus then there could be a sound system.

For condensers and such, there are many kinds of optics that are part of motion picture lights (leckos, and mole projector, etc.). One thing for sure is that cooling would have to be very aggressive. Putting a transparency in the "cookie drawer" of a lecko would vaporize it in about 5 seconds. That said, I thought that perhaps the focused beam with heat absorbing glass and cooling might do the trick if the slide is outside the elements.

It would be nice to have a screen larger than most movie theaters, with more vertical space. I did see such a screen at the Luxor in Las Vegas (the virtual IMAX ride, several stories tall) - but getting to rent that for a large format slide extravaganza would take a PR machine that is probably beyond even my wildest dreams. Hmmm, maybe I should try that - but I would need other, more noteworthy photographers to join me.

The scale and spectacle of it would be marvelous though.

Any other ideas, please let me know. And also, if anyone is interested in pursuing this as a coop venture of sorts - I'm definitely interested in hearing about it...

Captain_joe6
6-Aug-2007, 23:46
I think that we're missing one glaringly obvious solution here: use a LF camera. Pull the ground glass out and rig a film holder or some such to be a sort of negative carrier. Get your hands on a good APO enlarging lens and create some sort of light source, and you're well on your way. Graflex did it 50 years ago with the Graflarger accessory.

Ed K.
7-Aug-2007, 00:13
Thanks Captain Joe - but that would not hold up to the heat for the amount of light needed on a large screen for an audience. The image would be pretty dim. Projectors, even small ones for 35mm, generate a lot of heat - the radient energy alone of a large amount of unfiltered light hitting a projected piece of film is pretty intense. Heat absorbing glass that cuts the UV part would be needed. Your basic idea of having a focus capable box, a film holder and a lens is correct for sure - I'm sure that to be really safe, bright, sharp and effective - the solution needs a bit more than that.

To clarify - the projected size should be at least 8x10 feet, however much larger would be better still. I want the audience to see all the luminous nature of the images, and the image should be nice and bright, as in a good movie theater.

Some lenses would work fine if they can stand the heat. Other lenses might just melt apart where they are glued - if you know particular lenses that can take a lot of heat from projection use and still produce nice sharp images - please do mention them.

And so far, thank you all for some good input. I'm surprised that nobody has one of the projectors I need just laying around in their surplus collection...

Captain_joe6
8-Aug-2007, 15:27
I would imagine that it would be possible to construct a film carrier with heat-absorbing glass, possibly in a few layers, that would protect the negative enough to permit some length of viewing. Another trick would be to use fresnel lenses between the light source and negative and other methods in order to focus the beam and be able to move the light source farther from the film plane. At that point, if you're throwing enough refrigeration and ventilation at the light source and assembly as a whole, and despite the fact that the entire contraption would require nothing smaller than a Humvee to transport, you should be able to throw a nice big projection lens on there without fear of melting the cement.

Oren Grad
8-Aug-2007, 15:51
I think Noblex made a projector as large as 4x5 at one point. Do you think you could get away with 4x5 for the pictures you want to project? That would also reduce the cost and logistical hassle of making duplicate originals in case the projected ones get fried.