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Bill_1856
27-Jul-2010, 12:18
Has anyone tried using Lodima for enlarging rather than for contact printing? What sort of exposure time/aperture are involved, say 4x5 to 16x20? 150 watt bulb.

EdWorkman
27-Jul-2010, 12:20
Have you seen the information on the Azo site? It's a start, perhaps.

Peter De Smidt
27-Jul-2010, 12:25
Yeah, check out the site and forums. Last time I was there someone was developing a special enlarger head for the paper.

John Bowen
27-Jul-2010, 12:28
Bill,

Yes check the Azo site. I would recommend you ask the question there, someone may have tried it. Lodima just may be fast enought to use for enlargements.

My educated guess would be wide open on the lens and a 1 minute time for 8x10. If that worked, I'd try 8 minutes at 16x20. I hope my math is correct :-) This assumes a "standard" negative (ie Tri-X in HC-110). If you are using a stained negative (ie Pyrocat HD) you will likely need longer exposures.

Good luck and please let us know what you find.

Steve Goldstein
27-Jul-2010, 12:56
I tried using my enlarger as a light source to contact print a whole-plate negative on Lodima. It's a Beseler 45 with an Aristo head and V54 bulb. I have a Zone VI stabilizer, which I normally keep dialed down to the "F" setting (it goes up to around K, and gives 1/4 stop more light per letter, so I could have cut my printing time about in half). Exposure time was around 11 minutes. For comparison, the same negative contact-printed onto Ilford MG-IV, using the "F" setting, was in the 30-seconds range. All this was with a 135mm EL-Nikkor, used wide open, and focused so the edges of the empty 4x5 negative holder were sharp.

I suppose a 4/150 APO Componon would halve my exposure time, all other things being equal. I never tried hauling out the condenser head....

John Bowen
27-Jul-2010, 13:49
Steve,

Ditch the lens, raise the lens stage and lower the head so the light is little more than the negative you want to cover. Your times will be DRAMATICALLY lower

Drew Wiley
27-Jul-2010, 14:09
Just depends on the lightsource, and also probably on the UV transmittance of the lens
and carrier glass. Haven't done Lodima, but have done Azo in about 2 min with a
conventional 250W colorhead and fast (f/4.5) lens wide open. A powerful color mural
head would punch it no time flat.

Bruce Barlow
28-Jul-2010, 03:28
Yeah, Mr. Bowen is right, as usual, Bill. You're not going to get enlargements out of Lodima with any exposure time that you'll stomach. "Turn on the light and go out for lunch" isn't a viable strategy.