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This may seem really bsic, but how do ferrotype plates work? From what I understand, you can dry a fiber based print on a ferrotype plate to obtain a glossy surface. This must require proper paper(what type?) and does the ferrotype plate have to be heated?


-- Mike Castles (photomc@flash.net), December 02, 2001


Fiber-based paper coated with a thin layer of gelatin can be ferrotyped. This is, as I recall, labeled an F surface. There may be other surfaces that work, too. The gelatin is not apparent, and the prints are often matt dried and not ferrotyped at all. Ferrotype tins or the glossy, metal surface on a drum-type dryer are used. The metal and print surfaces must be clean, at least devoid of specks that might stick into the paper surface and cause little nonglossy spots. I guess some heat is needed to help soften the gelatin and promote its taking on the slick surface texture of the ferrotype tin. Heat is certainly needed to speed up drying, although ferrotyping is said to work best if drying is slowed down some from what you'd use otherwise. I must admit, I've never been able to consistently get all-over gloss on prints -- there were always big unglossed spots. There are waxes and so on that are supposed to help, but I never tried them. I finally gave up ferrotyping altogether. Now, if I want glossy, I use glossy RC paper. However, some folks claim to have no failures with ferrotyping.

-- Keith Nichols (knichols1@mindspring.com), December 02, 2001.

If you are wanting the glossy surface, you probably need to buy Pakosol to soak or "condition" the prints before the glossy surface makes contact with the plate or drum roller. About the only place I know to buy Pakosol is Calumet Photo, and you have to buy 1 gallon (will do several thousand prints, so it should last a while).

Without Pakosol, you will most likely get an "oystering" effect. The print is not ruined, as you can wet it again. Ferrotyping produces a really glossy surface that can't be obtained otherwise with fiber paper (at least I don't know any other way). But it is a pain in the neck, and personally I don't like the glossy look anyway. I have a drum print dryer, but when I use it I dry with the back of the print to the drum. Works fine, and seems to add a little more contrast to the paper.

-- Jim Rock (jameswrock@aol.com), December 02, 2001.

Ferrotyping works by providing a perfectly smooth surface for the prints to dry on. The paper you use must be glossy to begin with.

The ferrotype plates must be immaculately clean, no easy task as implied above.

My recollection is that ferrotyping was originally done to provide a completely untextured surface for halftone reproduction. With the smooth surface, no trace of texture carried over into the halftones.

Today, RC papers provide this textureless property without the major hassles of ferrotyping. Since permanence isn't of importance for the reproduction prints, RC is fine.

-- Charlie Strack (charlie_strack@sti.com), December 03, 2001.

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