How do you measure the density of a plate during development? Is it necessary to buy special equipment for this?
Frank - Tue, Jul 20, 99 08:47:54 PM
Hi Pascal. The easiest (and cheapest) way is to contact your local photo supply store and buy a few pieces of neutral density film. I paid around $1.89 or so for a large sheet of .5. I can cut this up into pieces and combine the pieces to match, say, a density of 1.0 or 2.0.
Just hold your sandwich up to your safelight while your developing your film or plates. When your plate matches the density of the sandwich, you've got it.
Also keep in mind that there will be areas of your hologram that will become much more dense than others, depending on the reflective qualities of the object being recorded. You need to keep an eye on the areas that are reaching your desired density first. This will be especially true for any object that has high areas of reflection such as a polished metal area, etc. You do not want to "burn out" this area of your hologram -- yet, at the same time, do not want the other areas to be underdeveloped because of it.
After time, you can "eye ball" density -- where you get to the point where you do not need any reference at all anymore.
Bottom line: get in the ball park of your target density and you'll be OK.
Frank 207.16.159.216
Brian Nichols - Wed, Sep 13, 00 04:20:44 PM
Think about using a 300 ion laser, emulsified plates, (which are made in Belgium,) Kodak developer, potassium bromide and sulfuric acid for the bleaching process, and 2 hours for the whole process..... 207.160.161.212
Brian Nichols - Wed, Sep 13, 00 04:24:37 PM
I forgot; Isopropyl Alchohol: this process is used to make holographic
gunsights. (I hope this is appropriate.)
bhn 207.160.161.212
- Thu, Dec 21, 00 01:22:38 PM
and how ca n I controle my Stoops. By this I meane, if I want to overexpore one stop how maeny % do I have to Add to my devlopme
nt time 212.87.117.249