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View Full Version : Making Modern Magic Lantern idea thread, LED?



Randy Moe
10-Aug-2016, 17:28
I have long wanted to project Large Format slides on walls.

At least 4X5 as it may be the best size. Or 2x3?

I find ALL existing 35mm and 6X6 slide projectors pretty tired and old. Hot, expensive bulbs that blow out all the time. I have bought and rejected many.

I tried OHP and considered BAUSCH AND LOMB, Golde, etc, but they are either very expensive or cheap mantle pieces.

The earliest Magic Lanterns were candle lit, then gas lit and finally carbon arc. Very old tech.

I am thinking at first use a tilt head Beseler and add a powerful LED lamp. I want this to shine brightly!

Assuming a very dark room,

How many lumens?

Color temp?

Yes WA enlarger lenses would be ideal, but they are not easily found at any price.

I have 150mm Rodagon, but maybe a faster lens would be better. Radar 4.5?

Point source with condensers or diffusion.

I know this is similar to mural printing on walls, but I want way brighter positive images.

These are a new category in LED, but not yet available singly.
(http://www.ledtronics.com/Products/product_new.aspx?id=LEDRK01DL-150W-XCW-101WD&d=High%20Power%20LED%20Retrofit%20Kits)
All ideas welcome.

LabRat
10-Aug-2016, 17:34
Just think what an enlarger would need to project... Use enlarger parts... And use a bright projection screen...

Steve K

LabRat
10-Aug-2016, 17:38
Oh, and try a fast projection lens instead of an enlarger lens... That would be the big difference...

Steve K

Drew Bedo
11-Aug-2016, 06:44
Isen't this basically the concept behind an enlarger?

Randy Moe
11-Aug-2016, 07:03
Isen't this basically the concept behind an enlarger?

Yes, but I want it very bright, so I need a powerful 'and not hot' light source.

A cold light head won't do it, and I want the best color temp for both E6 chromes and B&W positives.

I want to project up to 5x7 and 8X10 'slides'.

I do not want a digital transparency, analogue process only.

Drew Wiley
11-Aug-2016, 08:43
How glass plate color separation negs were originally projected was with three aligned carbon arc projectors. Talk about hot and bright! LED is actually rather weak and not particularly versatile if you consider you need to focus the array. Someone showed me the brightest unit I have yet seen two days ago. I told them to be very careful where they aimed it, or I literally wouldn't be able to drive home that evening! But all those lumens were on a wing-shaped array designed to light up a very large space. Seemed about three times brighter than the market equivalents currently available in this country, and with much more reliable components. Expensive, naturally. I think halogen would be the most likely choice. You could invent a water-cooled housing if necessary, with coils, if you plan on auditorium sized slide shows. Otherwise find good projector bulbs like US or Japanese-made ELH, which can run straight 115 voltage in more than one burn position. Your bigger problem is how to keep the film flat. There are still quite a few Gepe 6x7 anti-Newton glass slide mounts laying around here and
there, but I've never personally seen anything bigger.

Drew Wiley
11-Aug-2016, 08:48
... Yes, you could have Focal Point cut you a sandwich of AN glass at around $100 per sheet, but you'd need quite a few pairs of this to actually make a slide show that didn't suffer from long interruptions cooling and remounting them. I once had a big horizontal Durst color mural enlarger that would make a helluva projector.
Of course, the cooling fan alone sucked up more wattage at 220V than the typical industrial table saw motor, and if you left a transparency in the thing more than
a minute it would be 25% faded.

Randy Moe
11-Aug-2016, 08:57
I have 10 sheets of 8X10 AN.

I might try offroad racing car LED.

Maybe my slide show will use 4 projectors and switch them on and off.

Or I rent one of those Laser signwriters and call it a day. :(

This will be a wacky Art installation anyway...

Drew Wiley
11-Aug-2016, 10:01
If this were a decade back when a full selection of chrome films were still available, I'd preserve the original chrome and make 8x10 dupes. Once Cibachrome
ended, I sold off all the remaining boxes of Fuji dupe film in my freezer, so can't help there. Of course, you could go back to the 3-projector method using black
and white separation negatives; but there is a pretty steep learning curve doing matched sets from your original chromes. The advantage is that these wouldn't
fade, and they'd do a superior job reproducing the full scale and hues of your original. But 8x10 T-Max ain't cheap either, though FP4 could be substituted with a
bit more fuss. You'd want to hypothetically learn the technique with 4x5 film anyway, unless you want the piggy bank to have a quick death rather than slow one.

Randy Moe
11-Aug-2016, 10:08
If this were a decade back when a full selection of chrome films were still available, I'd preserve the original chrome and make 8x10 dupes. Once Cibachrome
ended, I sold off all the remaining boxes of Fuji dupe film in my freezer, so can't help there. Of course, you could go back to the 3-projector method using black
and white separation negatives; but there is a pretty steep learning curve doing matched sets from your original chromes. The advantage is that these wouldn't
fade, and they'd do a superior job reproducing the full scale and hues of your original. But 8x10 T-Max ain't cheap either, though FP4 could be substituted with a
bit more fuss. You'd want to hypothetically learn the technique with 4x5 film anyway, unless you want the piggy bank to have a quick death rather than slow one.

First reverse 4x5 X-Ray and learn with FP4 , then we get crazy.

Art is never cheap.

Drew Wiley
11-Aug-2016, 11:36
X-Ray film isn't panchromatic, so it wouldn't have any practical value in this instance. By far the most cooperative film for color separations is TMX, followed by
TMY, followed by FP4. There has to be linearity of tricolor response not only at the middle of the curve, but over a long straight line sufficient for the entire range of the original transparency itself. A lot of tricks to this. There are people who can do separations commercially for you, or you can do it entirely in your own darkroom; but expect only blood, sweat, and tears for a couple of months. If you are willing to endure it, I can give some further tips. And of course, dust control
must be undertaken with fanaticism.

Fr. Mark
11-Aug-2016, 21:00
XRay film might be reversal processed, but all of it I've ever seen is on a blue base which would make odd slides. Some XRay film is pretty orthochromatic. I got some clouds well captured today, for instance.

Randy Moe
11-Aug-2016, 21:34
I enlarged 6x17cm onto 14x36 inch Kodak CSG to make a positive and on my light table the blue is not that visible.

Don't forget I am not trying to emulate the past, but make what we have now work for me.

I posted an iPod image of that in X-Ray.

Maybe I should go play with the ALT Print crowd as I seem to be moving off mainstream.


XRay film might be reversal processed, but all of it I've ever seen is on a blue base which would make odd slides. Some XRay film is pretty orthochromatic. I got some clouds well captured today, for instance.