Mylar sheets for alt process printing

[CreationBear]

Like a lot of y'all it seems, I'm in the process of kitting-up in anticipation of exploring a few alt-processes this Spring. Since I'm using in-camera negatives, I wanted to use a mylar sheet between the film and the sensitized paper as both a safety measure and to also to provide clean borders when taped with rubylith.

A quick search turned up a lot of ~5 mil sheets that are advertised for stencil applications, while Sandy King once mentioned that there's a little thinner option available from Light Impressions. (I'm assuming that it's something like this:http://www.lightimpressionsdirect.com/foldlocktrade-sleeves-8-x-10-50-pkg/protective-sleeves-prints-negatives-records/

Which is all a round-about way of asking your help in sourcing:), with any added insights into the process greatly appreciated as well.

[Drew Wiley]

Large sheet of frosted mylar should be available from any large art supply store. The thicker 5-mil version will be a lot less subject to crinkle marks than the thinner 3-mil, but still should be carefully inspected for blemishes, sheet by sheet. That's why I prefer to buy large sheet brick n' mortar store style, where they're stored in big flat drawers, allowing me to pull my own sheets and inspect them, rather than receiving them roll up by someone else. I can't comment on the specific application you have in mind. But just realize that there is an important distinction between frosted mylar sheets and similar looking frosted acetate, which lacks the dimensional stability of mylar, yet is often sold in the same places at slightly lower price.

Otherwise, I didn't know Light Impressions was still around. They seem to have largely collapsed years ago, ever since they sold out and moved from NYC to LA. If you do need an internet source for these sheets, there should be plenty of other options to choose from.

[CreationBear]

But just realize that there is an important distinction between frosted mylar sheets and similar looking frosted acetate, which lacks the dimensional stability of mylar, yet is often sold in the same places at slightly lower price.


Excellent, that's very helpful--we do have a Jerry's Artarama here close to campus, so that will be my first stop to see what I can sift through.

[gypsydog]

You do realize you can't use frosted mylar, it must be clear. 1 mil is best, some say 2 or 3 is okay. It usually comes in rolls and is not really reusable.

[domaz]

Yep thin as possible is very critical. Especially with any alt process where the image appears on a gelatin base (think Carbon Transfer or any Silver process with gelatin/albumen sized paper) since they are very inherently sharp processes, too thick of a piece of mylar would be noticeable.

[CreationBear]

It usually comes in rolls and is not really reusable.

Excellent, thanks for the insights, gents--I'm seeing a product called "drafting film" that might fill this need.:)

[gypsydog]

Drafting film is usually matte, you need clear mylar or you will end up with a blurry mess!

Like this https://catalog.cshyde.com/viewitems/films/mylar-polyester-pet-film
Click the optically clear and 1 mil



Excellent, thanks for the insights, gents--I'm seeing a product called "drafting film" that might fill this need.:)

[CreationBear]

you need clear mylar or you will end up with a blurry mess!

Excellent, I appreciate the hand-holding for what appears to be a solution looking for a problem;). That said, is this product closer to what I should be envisioning? https://www.amazon.com/Grafix-Dura-Lar-14-Inch-17-Inch-Sheets/dp/B004O7A92O/?_encoding=UTF8&pd_rd_w=DBbEb&pf_rd_p=29505bbf-38bd-47ef-8224-a5dd0cda2bae&pf_rd_r=QRBCB5AK02BDS4MCBSM0&pd_rd_r=85e3df44-e14d-4d06-9aa7-8d9dcdbc04f3&pd_rd_wg=lbxMT&ref_=pd_gw_ci_mcx_mr_hp_atf_m&th=1

PS: just saw your link: very interesting!

[jprofita]

I bought this after ruining a negative with print out palladium. I would cut several pieces from the roll and store them in a print sleeve to lessen dust. Each sheet was good for several uses. Since then I have switched to develop out chemistry where holding moisture in the paper is not as critical...so I quit using this material.

https://www.usplastic.com/catalog/item.aspx?itemid=40081

[CreationBear]

I bought this after ruining a negative with print out palladium. I would cut several pieces from the roll and store them in a print sleeve to lessen dust. Each sheet was good for several uses. Since then I have switched to develop out chemistry where holding moisture in the paper is not as critical...so I quit using this material.


Excellent, thanks so much for the link and the pointers--like a lot of people I think, I'm a bit put off by the moisture issues with ziatypes so hopefully
VDBs will be a less hectic intro to POPs.:)

[jp]

overhead transparency material FOR LASER PRINTERS is mylar. Normal clear overhead transparency material melts in a copier/laser printer and is not mylar.

[sanking]

For a number of years I have used Grafix Dura-Lar clear as protective cover for printing digital negatives with UV sensitive processes. I generally purchase the product from Dick Blick, where you can find it in a variety of sheet sizes as well as roll sizes. It is also available in various thickness. I use the 0.002" thickness. Avoid the 0.001" thick Grafix Dura-Lar as it has a UV coating that blocks 2-3 stops of UV transmission, making it impractical for contact printing with UV processes.

Clear polyester is available from a wide variety of other sources, but be aware that some of it has a UV coating, which may or may not be mentioned in sales literature.

Sandy

[Drew Wiley]

Well, I get it now. Exposure through the back, ala carbon transfer or something analogous. Same sources. But going very thin would seem to make it all the more beneficial to examine sheets in person if possible. And perusing through my various samples of polyester/mylar, it is apparent that some of those brands have a slightly yellowish flavor which would block UV somewhat, just like Sandy warned. I'd ask for a small sample in advance if you can't select the sheets in person.

[CreationBear]

I use the 0.002" thickness. Avoid the 0.001" thick Grafix Dura-Lar as it has a UV coating that blocks 2-3 stops of UV transmission, making it impractical for contact printing with UV processes.


Ha, thanks for that information--that's a gremlin that I'm pretty sure I wouldn't have been able to interpolate.:) At any rate, I appreciate all y'all--having folks being able to articulate the intricacies of just the basic materials really saves us newbies hours and hours.

[sanking]

Yep thin as possible is very critical. Especially with any alt process where the image appears on a gelatin base (think Carbon Transfer or any Silver process with gelatin/albumen sized paper) since they are very inherently sharp processes, too thick of a piece of mylar would be noticeable.

You are correct. In carbon printing with digital negatives that have high resolution there is definitely some slight loss of print sharpness when using thick mylar of 0.005" compared to thin mylar of 0.002".

The above assumes the use of a vacuum frame. Your results may vary with contact printing frames.

Hard to be specific with processes like albumen, pt/pd. and Vandyke Brown and Kallitype, but as a general rule if you have a very sharp negative I would always use the thinner mylar.

Sandy