How long would the exposure time be with a 35mw diode on a 2.5"x2.5" plate? I want to use a camera with a remote trigger for a shutter. It can do any time between 2 seconds and 1/1000 of a second.
Ronny Andreassen - Fri, Aug 06, 99 10:39:32 AM
Hi Kraken. It depends on wich type of holographic film or plate you are using, and if your plates have to be preswelled before use. I'v made 4"x5" single-beam holograms with my 35mW laser at 658nm. I'm using BB-640 plates and have to preswell them before use. This process will halve the exp.time. If you messure the exp. time to be 1sec. on AGFA 8E75 the exp. time on BB-640 will be appr. AGFA X 4+ after preswelling." +" exp. time depends on how much the object you are using will reflect the light back to the plate/film (obj. beam). When using stone as an object I'v to expose 6 X AGFA after preswelling. All the tests I'v done tells me that the exp.time on AGFA 8E75/BB-640 is 1:8. I know that other holographers have 1:4 as their rule, and I do not know why? Well, you have to try and fault to find your exact exp. time on your plates. My personal Rule is that the plates have been perfectly exp. when the developing time takes 2min. to give the right Density (nearly opaque) when making reflection holograms. Hope the best for you........ronny (sorry for my bad english) 130.67.15.242