acrylic versus glass for negative holder?

tonyowen

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I've an ancient 2 3/8" x 3 3/8" negative holder with only one piece of glass fitted.
Are there any negative [no pun intended] reasons why 2mm acyclic cannot be used in place of 2mm glass to refurbish the negative carrier?

regards
Tony
 

Ian Grant

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It's unlikely the acrylic is optically up to it, if you said CR39 which is the resin used for Glasses and filters like Hitec, Cokin etc then maybe.

I'd be surprised if the negative carrier uses 2mm glass, usually it's much thinner. as it happens I came across my thinner glass over the weekend, I've made new glass inserts in the past for a Durst enlarger.

Ian
 
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tonyowen

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Ian Grant said:
It's I'd be surprised if the negative carrier uses 2mm glass,
Click to expand...
Ian, yes, the in-situ glass is circa 1mm thick [determined] measurement is around 0.045" [I'm assuming that the age of the item means imperial measurements were used in 'those days']

My micrometer will not reach as far as the glass so I had to measure glass plus metal surround and take away the measured metal surround thickness.
I do not want to attempt removal - which would/could break the glass..

Also it seems that 2mm is the minimum thickness nowadays for glass

regards
Tony
 

Patrick Robert James

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I've used acrylic before, non-glare framing acrylic, above the negative as a sort of anti-newton glass. It worked fine. Only problem with acrylic though is it tends to attract dust because of static, and it is easily scratched of course. You could use it though.

You can buy thinner glass at Edmund Optics. Glennview, who has darkroom equipment, sells coated glass and IIRC he will cut it to fit for you. Kinda pricey though.

I'm just providing this for information though. You should take Ian up on his kind offer...
 

voceumana

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i concur with Pieter12. Bad choice of materials for a negative carrier for those reasons.
 

DREW WILEY

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Acrylic is not dimensionally stable. It tends to warp toward heat and light. As already mentioned, it scratches easily and is quite electrostatic, attracting dust. If your negs are just 6x7 cm, then old Gepe 6x7 slides mounts with Anti-newton glass on both sides do a good job.
 
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