Selasa, 25 Maret 2014

Workshop on platinum printing from digital negatives workshop

The Center for Alternative Photography (CAP) is a workshop based educational program developed 10 years ago.  It holds workshops on historical, emulsion, and alternative photographic processes. CAP later morphed into the Penumbra Foundation, a non-profit, member supported organization dedicated to preserving historical and emulsion based photography and maintaining its relevance as an artistic and educational tool in the evolving digital age.

CAP has workshops in kallitype, albumen, cyanotype, Van Dyke brown printing, gum bichromate, wet plate, with some courses partnered through ICP (International Center for Photography). It also has its own tintype studio on the premises at 36 East 30th Street, New York.

You might recognize this picture in the print above from yesterday's blog post. I took it while walking on the way to the weekend workshop on platinum printing from digital negatives. The photo was taken with my X-T1 and 35mm lens and converted later in the workshop to a black and white negative that you can see at the top of the photo above. At the bottom right is the final platinum/palladium print made from the negative. 
This past weekend CAP held a 2-day hands-on workshop on making platinum/palladium prints from digital negatives taught by the excellent photographer, Carl Weese. Platinum/palladium is a contact printing process so the negative must be the same size as the final print. To achieve this a negative can be made from a digital camera file or scanned from an original film negative, scaled to size in Photoshop, and printed on a digital printer. This is the process being used to make my platinum prints.

I used to use digital images taken with a Nikon D800 because of its high resolution, but after some experimentation I have found prints made from the smaller-sized, 16bit sensor of Fuji X-cameras, such as the X-Pro1, X-E2, and new X-T1, seem to deliver an image that more closely matches the quality I used to achieve from 6x6cm film negatives. I think the reason for this is that the D800 files deliver almost too much resolution, whereas the Fuji files introduce a bit of graininess more like film. Whatever the reason, I have had a much easier time and better results since I began transferring Fuji-X digital images to platinum prints.

Platinum prints are known for their superior, extensive tonal range. The process was invented in the 1870s and has qualities never surpassed by later methods. As Weese says, "Silver prints, and now digital prints, can be very, very good, but neither can actually duplicate the tone, surface, and color of a well-made platinum/palladium print." The Platinum/Palladium printing is done on archival graphic media, usually watercolor paper, and with the Pt/Pd embedded right in the paper it produces the most permanently stable results.

Below are some photos from the workshop showing some of the progressive steps in making a print.

The most important part of this entire process was learning how to create the right negative to print. Platinum printing has a very extensive tonal range, way more that in silver printing. One of the most difficult parts of the process for me was finding how far I had to extend the tonal range in Photoshop to achieve a good negative. Because the tonal range is so extensive, expanding the image data to accommodate it was far more subtle than the post-processing I normally would do. The image on the computer above held a very wide dynamic range of tones. Spreading them out to cover the tonal range of a platinum print was a real learning experience.

The digital negative for platinum printing is printed on a transparent medium, such as Pictorico Ultra Premium OHP Transparency Film shown in this photo. We used an Epson 3880 printer to create the final negative. The X-Pro1 I used for my week end project is shown in the upper left of the picture.

Water color paper cut down from larger sheets is marked out with an outline of the actual printing size.

The mixture of platinum and palladium plus any additives is medewinared out in drops sufficient to coat the chosen paper size.

There are two methods for coating the paper with the emulsion mix. In this workshop we spread it with a brush. You can also use a glass cylinder with attached handle. Platinum is only sensitive to extreme UV light, like that from the sun, and can be worked  in a room lit with low wattage tungsten lamps. 

Time to cook the print in UV light. The negative is sandwiched with the emulsion prepped paper and placed in a frame. This is then exposed to UV light in either a homemade or purchased box. In our case the exposure was eight minutes. Platinum is sensitive only to UV light. You could also expose it directly to sunlight, but medewinaring the time becomes a bit sketchy.

Next comes the wet development process. Here Carl is pouring the developer over the exposed paper. Results are immediate.

The print is developed for 90 seconds. One interesting thing about the process is that the developing solution essentially never ages. You can use it over and over again for years with replenishment only for lost liquid.

After development the print goes through a wash, two stop baths, and a final wash before being hung up to dry. Platinum printing is the most stable printing process out there. Final prints on archival paper will last pretty much forever. 
If you are interested in alternative photographic processes, or just want to have a tintype portrait made, it is worth a visit to the Penumbra Foundation anytime you are in New York. As they like to point out, the foundation is located right around the corner from where the famous 291 Gallery created by Alfred Stieglitz was housed on Fifth Avenue.

Further information and details for the Penumbra Foundation and Center for Alternative Processes (CAP):

Address: 36 East 30th Street, New York, NY 10016
Phone: 917-288-0343
Email: info@capworkshops.org
Website: http://capworkshops.org/
Office Hours: Monday to Friday 10:00am to 6:00pm

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