Update on the quest for dark slide replacement material.

I completed a fairly dimensional test of the plastic sheet material that appeared to be a perfect candidate. I took three sheets of the material and performed three individual image making comparative tests on a holder where one side I used the original dark slide and the other side of the 8x10 holder I used the plastic replacement material. On each image I allowed each side of the holder to be open to the sun for a reasonable period of time - consistent with normal field operations. I made three separate exposures one per double sided holder, processed the negatives and put them on the light table.

Unfortunately and much to my disappointment, even though the plastic material looks light tight, I can see areas in the replacement slide negative where the light worked its way through the dark slide material in varying proportions and had an adverse impact on the negative. This has to be a random event having to do with the manner with with this replacement material is manufactured. I was using 400 speed film and although 90% of the negative looks fine, the section that is slightly fogged is visually obvious. As a result I must conclude that the material that appeared to be so promising making a dark slide replacement is not suitable for the task at hand.

At this stage I feel we should see if through the forum we can see if anyone has a contact with Fidelity in some way so we can attempt to gleam their material source for dark slides. The other alternative would be to see if the English company making holders and cameras has a material source. I could not see a way to communicate with them.

I gave it a good go but the results are what they are. The material I used was a phenolic plastic material. I see this only as a temporary setback. We will collectively figure this out.

Thanks!