Recent content by Anthony Zingre

I want to thank all three of you. The last two comments gave me some real food for thought. Going with Bill's idea to just drop the lenses in place and see what happens in both directions by testing for attenuation of UVA at the print surface. Still waiting for the COB.

My question too. Maybe it would be better to just remove the condenser lenses entirely. I'm going to find out in about a week.

Hello, ic-racer. Not sure why your second comment didn't make it here but did on my email, but, good advice. I may be chasing unicorns but, light is light is light. If the condenser is blocking too much UV, there are ways of spreading that light out evenly. As a matter of fact, I'm guessing no...

At this point I'm going to say no. That said I have not tested it. The fan tower and power supplies are in place and I'm waiting for the COB to arrive. I say no but a gentleman on YouTube, Prussian Blue, converted his 4×5 Beseler, about the same age unit as my Omega Dii, and plows the light...

Thanks, Bill. Personally, I'd not heard this either and the big concern being the overall collomated (sp?) position of the two lenses. That, I suppose, merely reducing what Newton rings might be forming and not much else. Mine, however, look to be different. I'm taking them into work today to...

Of the two condenser lens present in the housing, one has more of a flatter, pancake shape compared to the other and has no edge roll when compared to the thicker lens which has an edge about 3/16ths thick. You know, one of these things ain't like the other and if I had a better way to measure...

Thank you, Niranjan. That clears up the confusion on Ethan's original post. Tony

Yes, that's understood. The point of sensitization then is to eliminate the need for UV light entirely, correct?

Here's the deal. I may have misunderstood what was being said here. I assumed some level of UVA was still necessary even if the sensitivity was shifted to the blue. Since I am more interested in cyanotype, and finding a UVA bulb at 365nm capable of exposing a print in a reasonable amount of time...

Good morning. Oh, you were asking the technical "why". Ok. I gotta get to work but given what Ethan experienced, does broadening the spectral response, i.e. more blue light sensitivity, by adding an analine dye like he's done increase the sensitivity of the emulsion only and decrease the amount...

Hello, Koraks. Thanks for the insight into this. To answer the why part of this involvement with actinic processes, yes, the obvious answer is just work with emulsions or papers designed for enlargement. I suppose they will be here for the foreseeable future. Right? Tbh, and because I've been...

Ok, home with time to think. My concern and an acquaintance and apparently a few here on this thread was that adding any dye that could cause silver bromide to become sensitive to a specific wavelength is that it would only be sensitive to that wavelength and roughly there abouts. Spreading out...

Thank you, sir. When I get home tonight I'm posting an experiment in digital but I think... well, you'll see. Back to work.

Thanks, Ethan! Tonight, when I get home, I'll clear this thought process up a tad and get on with it. Like you, the experiment is the real world for me as well.

As usual, I'm late to the forum. I'd read an article about the development of orthochromatic plates by it's inventor Hermann Wilhelm Vogel. His addition of an antireflective dye, Korallin made his emulsion sensitive to the yellow spectrum up to a, I believe, 590nm wavelength. My question here...