Cold light source vs normal? Difference?

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http://ctein.com/PostExposure2ndIllustrated.pdf

Page 57 ... :wink:

I think Mr Lyga is just asking for facts over speculation or myths.

I have two identical Beseler 4x5 chassis in my darkroom, one with the 45S "color" head and one with the standard condenser. I can make identical prints with either. The myth I find most interesting is that diffusion heads hide dust. Oh, puhleeze. The dust spots on my diffusion prints may be slightly lower in contrast, but they're just as sharp and require just as much spotting ...

Absolutely true.

If it hid a large dust particle, can you just imagine how much resolution would be lost. But the internet myth goes on and on and on , and just like the dictators propaganda, people believe it.

The other is stand developing. It makes streaks ( bromide drag ) that may or may not show. Certainly they will appear on the very best frame you ever shoot.

How about Rodinal being sharp. NOT. D76 1:3 is sharp, ugly but sharp. Time is around 16/18 min at 68 deg. Detail like you would not believe.

How about pushing film. You might get a little more shadow with certain developers, but not a whole lot. Diafine will get 1200 with Tri x, but image is ugly. Extending time in D76 is a waste.

Mixing ISO on the same roll. No. All you get is some over and some under exposed frames.

How about my fiber prints dry flat on a screen.. Get real. Only two kinds of dryers work. Those that interleave prints with blotters and corrugated boards and have a fan blow, and those that tape a print to a drawing board or glass plate, ferrotyping, or the big 36" drum dryers,

Those that say they can weight a cockled print flat under weight. No. It is cockled because the edges are longer that the center in dried state. Unless you have a paper stretcher, there is no way to fix or you have a poor definition of flat. The metal industry gets wavy edges from rolling and they use stretchers to fix. I used to be a roller. A rolling mill needs parallel rolls to roll flat. Control with jacks on ends and differential cooling . There is art to it. It is really an extrusion process.

The only thing I will concede is I have prize neg that got a scratch where the roll end flipped up. A condenser clearly shows the line. A diffuser does not. Leica V35 and Focomat IC, latest Leica lenses on both. But hide dust no way. and the line shows as white and way to fine to spot. Finer than if you lost a hair on the paper under the enlarger.
 

cliveh

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The sad problem is glass carrier (needed to prevent negative popping with condenser heads) can be a dust nightmare due to the focused light hitting the dust on six surfaces and rendering the particles in great detail in your prints. Diffuse light usually blurs out the dust on the top and bottom of the glass carrier. The dust trapped between the glass can still show in all its intimate detail.

If you don't have the enlarger on very long, not enough heat will be generated to cause popping.
 

DREW WILEY

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All it takes is a temp differential or bit of inherent film curl. I gave up on "glassless" decades ago; it's kinda like eating uncooked meat, Australopithecine-style, at least if you're anticipating reliably sharp prints. Lots of film isn't flat to begin with; so it certainly won't be in a glassless carrier. 120 roll film is the worst.
 

ic-racer

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For the same reason, glass can also isolate your emulsion from dust,

Good point. This is a reason I use 1:1 projection for same-size multigrade printing, rather than a heavy glass or contact frame under focused colored enlarger light. I might do 20 little test chips to work up a print, so there is less manipulation of the negative when it stays in the glass enlarger carrier.
 
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