emulsion exposure time

[noortrd]

Which emulsion is good . short exposure time or long exposure time?

[tpitman]

I'm not sure I'd characterize an emulsion's exposure time as the definition of its "goodness" unless you have a very weak exposure unit where a faster emulsion would speed up production. Dual-cures vs. premixed each have their pluses and minuses. I've settled over the last few months on Saati Grafic HU, a dual-cure with moderate exposure time but very good definition and excellent reclaim. Lasts over 2 months after mixing the diazo, and I buy it by the quart so none goes to waste. Takes more time/light units than Murakami HVP, which I like for its transparency and ease of registration, but the Murakami is inclined to turn gummy upon reclaim without good post exposure, and sometimes a bit even with it. The Grafic HU just melts off the screen as soon as the remover hits it.n That's my idea of goodness, anyway.

[Gilligan]

Good still use more entries, but it's a start.

https://docs.google.com/spreadsheet/ccc?key=0AgdPJ7c6eSh6dFZ4bVBSTFVXZzZ5eFNvX3JyVk9vQ0E&usp=docslist_api

[noortrd]

May be short time is better bcs electricity is expensive.

[Grumpy Ole Artist]

I've been using Ulano RLX (diazo-sensitized) for EVER...Thrown/given away soooo many samples of "modern" emulsions over the years...I now tell any rep walking in with one to just take it back to the car! For my processes/equipment (vellum, with all of it's attendant poor toner density/ milky background issues, a glorified tanning bed for an exposure unit, a wind-up egg timer, no integrator, etc.), I need a slower emulsion to get a usable screen. The exposure 'window" on the newer emulsions is so narrow, that either the emulsion falls out when it gets wet (underexposed) or the image is completely blown away (over-exposed). My exposures range from about 4 minutes (for 230 mesh) to about 20 minutes !!!!!
(61 mesh)...Sssssloooooow!
I DO like the sound of the Graphic HU "falling out" in reclaiming. I am very frustrated by my emulsion reclaim times here...Seemingly just can't get a full burn/crosslink with vellum and a single exposure....I miss my old darkroom with its' AGFA stat camera, point light source/integrator, contact frame, and FILM POSITIVES...Waaahhh!