Photopolymer Exposure Time

torokta
on 5 Apr 10 (13:36)

Has anybody used Toboyo Printight Photopolymer? The manual does not mention the exposure time.

http://www.williamson.ca/products/photopolymer/toyobo/

there is a table with 21 step grayscale values instead.

What does it mean?
How can I compare a yellow photopolymer to a grayscale???

Vrooooom
on 5 Apr 10 (14:26)

I believe that table is your step wedge test. You use it with a plate and do a test exposure and then use your results to gauge the best result.

Good thing to do every so often as the light source sometimes drops in output near the end of its life…

jhenry
on 5 Apr 10 (16:15)

You will need to purchase an exposure step wedge from your plate supplier (or any graphic arts supplier) and expose a plate through it as Vrooooom has indicated. On the envelope the step wedge comes in, there is a table which will tell you how much to increase or decrease the exposure time to get the solid step indicated on the Printight data sheet.

torokta
on 11 Apr 10 (12:38)

Thanks just found the answer on boxcar site

http://www.boxcarpress.com/photopolymer-supplies/stouffer-gauge.html

rwarnoldjr
on 11 Apr 10 (23:55)

Torokta, I believe the plates the Boxcar sells are Jet plates. If I am correct and they are then there is a difference in the the exposure and washout times. I have used both and prefer the Printight plates myself.

Robert
The Dog House Press