Dry Mounting Damage

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I finally got my own dry mount press (Seal 210) and have completely cut the cord from the local university darkroom. Consistancy is much better. However, I think I may be damaging the emulsion on some prints, but it is subtle. I use Forte polycontrast neutral paper with a glossy finish. My press is set at 200 F (checked with a thermometer). I have two pieces of 4 ply on top and one under the print. Time in press is 3 minutes. If you look at the mounted print at just the correct angle there seems to be a bit of a spotty film on it, almost starch like. It is hardly noticable and is not noticible at all behind plexiglass. Am I damaging the emulsion ? If so, what do you think it is from, too hot, too long, too much pressure ??? Thanks.

-- Paul Mongillo (pmongillo@thurston.com), July 13, 2001


Typically you set the temp for the mounting media you are using. Some are low temps but is sounds as if your press is a little to hot. You are using release paper on top of the photo right?!

-- Scott Walton (f64sw@hotmail.com), July 13, 2001.

Paul, Make sure that the paper and board that faces the emulsion surface of your print are absolutely flat without any cuts or defects. Any imperfections will be ironed onto your print permanently.

The starchy appearance may be from the release paper. Your temp may be too high for the type of release paper you are using.

-- Dave Anton (daveanton@home.com), July 13, 2001.

If you measured the temperature correctly, it is not too hot.You should do this at the print surface level.The best way to do this is Seal's temp test strips, it may sound like an unnececessary expense, but it's not.MT5 needs at least 200 F (200-220).If you use archival mount, you can set it lower.Seal's recommended temperatures are a little lower than optimum.2 pieces of 4 ply is not really necessary, i use only one.3 minutes is too long, when you use a single piece of 4ply on top, 2 minutes should be sufficient unless the print is 16x20 or larger.I can't tell you if the pressure is too much on your press, but it is the the heat that bonds the print and the tissue,not the pressure, so if it feels too tight, loosen it up a little bit.You should repeat the temperature test at the new pressure setting.

Having said all that, unless the temp and pressure are grossly over, i don't see how it can damage a fiber print.

-- Cem Topdemir (cem-1@softhome.net), July 13, 2001.

One last thing, if you are using some sort of release paper, try not using one.Like Dave said, it might be leaving a residue.I never felt the need to use one of those.

-- Cem Topdemir (cem-1@softhome.net), July 13, 2001.

Paul, Are you pre-drying/shrinking the print in the press at low presure before mounting? Too much moisture in the paper can cause the indications you describe. If you live in an area with high humidity, the board needs to be treated in this manner also.

-- Bruce Wehman (bruce.wehman@hs.utc.com), July 13, 2001.


We too have recently acquired a Seal 210M and are now just beginning to use it, and you may find our experience helpful since so far emulsion damage is not noticeable.

We just mounted a half dozen 8x10s on 11x14 rag boards, all Oriental Seagull fiber dw G2, 3, and 4, glossy. We set the press at about 175 and pre-dried prints and boards, with release paper top and bottom, for about 60 sec. We use Seal archival Buffermount, recommended temperature 170, minimum 160. Our sandwich (from top) consists of silicone release board, Seal ColorMount coversheet, art, and release paper. Time in press about 60 sec. when guage read around 170, maybe 90 sec. when the temperature dropped, but never higher than 180. So far as I can tell, the mounting took and with no signs of damage to the emulsion. Beginner's luck, I guess. As suggested in previous posts, I suspect it's either because your temp is too high or your time too long, or both. Hope this helps. Nick.

-- Nick Jones (nfjones@pitt.edu), July 13, 2001.

I do pretty much the same thing Nick does; I _think_ I've seen the odd phenomena described once. Rather than stuff on the print surface, it's that tiny spots become shiny and is caused by a board either above or below the print that isn't smooth enough.

-- John Hicks (jbh@magicnet.net), July 14, 2001.

paul a few ideas on causes and solutions. firstly,are you using any hardener in your fixing baths? next how long are you washing the prints and at what temperature? modern emulsions tend to have a variety of problems that were not evident even 10 years ago,use of a clean sheet of seal release paper is sometimes useful sometimes not. you might try a sheet of brown kraft paper as this will not leave a residue-also you must preheat all items especially mountboard as others have stated. i also would suggest you noy use any buffered materials,either boards,papers or mount tissues as these can be/are harmful to photographic prints. finally try just one sheet of 4-ply board with a cover sheet not 2 pieces and maybe 180 degress at 45 seconds and be sure upon removal to place weifgt on the item just mounted.

-- robert (ralfoto@aol.com), July 20, 2001.

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