RE: [PPLetterpress] Re: Uneven ink on plate
- There is more than one "Stouffer scale". The company makes scales with different density ranges and also different density steps from one number to the next.
the Papertrail Handmade Paper & Book Arts
New Dundee, Ontario
From: PPLetterpress@yahoogroups.com [mailto:PPLetterpress@yahoogroups.com] On Behalf Of Eric
Gerald has a good point here. 18 is a very high point on the Stouffer scale, when 14-15 are the specifications for Toyobo K-series plates (at least in my old spec sheets). Sure it is a Stouffer scale and not a different type?
My drying method like everything else is admittedly low tech. I typicaly lay a paper towel over the raised surface to remove excess water then gently blow warm air on the plate from a hair dryer before post exposure. That's probably not the best way, but I've never had any problem with it using hand-processed steel backed (145HSB) plates. This photo shows plates I made Monday this way for making round stickers for a local rock band: http://www.flickr.com/photos/9645031@N07/8652743991/lightbox/ At left you will see the original bitmap created in Photoshop and printed on my laser printer at 200 percent (40 dpi halftone); the camera negative made on rapid access film shot at 50 percent (raising the dpi to 80); the actual plates after exposure and processing; and the finished stickers after being die cut to 3 inches round. I find this method satisfactory for general work. However, I don't actually make wedding invitation plates this way. For high-end work I generally have the chosen graphic artist order professionally made plates from a supplier of their choice (especially when troublesome thin hairlines common to calligraphy and script type is involved). --Ed
- Thanks to everybody for all the help with this problem! I now have lot's of drying techniques to try.
--- In PPLetterpress@yahoogroups.com, "Eric" <Megalonyx@...> wrote:
> Gerald has a good point here. 18 is a very high point on the Stouffer scale, when 14-15 are the specifications for Toyobo K-series plates (at least in my old spec sheets). Sure it is a Stouffer scale and not a different type?
> Then consider the image itself. What is shown is essentiually a reverse, which should be given a shorter exposure than whatever the "normal" exposure is to avoid filling.
> To remove any surface moisture or debris, I don't use a sponge but rather wipe with a laundered cotton rag. bunched up as an etcher would do when wiping a plate with cheesecloth. Sometimes I do use compressed air but you may blow slick photopolymer onto the surface, and possibly blow over underexposed elements such as barrel-bodied lines and dots. A very careful wipe takes care of the surface, and the time spent in the dryer will shrink some of the non-image areas that were almost at printing height when still wet.
> --Eric Holub, SF
- --- In PPLetterpress@yahoogroups.com, Kevin Martin <kpmartin@...> wrote:
>The 21-step Platemaker's gray-scale has long been standard in commercial printing, and is what is sold by most suppliers of relief photopolymer plates. It is also what the manufacturer's specifications mean when they refer to Stouffer (they may also give values for other brands such as Dainippon etc.).
> There is more than one "Stouffer scale". The company makes scales with different density ranges and also different density steps from one number to the next.
--Eric Holub, SF