Category: The Positive

Prints and all their jazz

The Paper is Key

Posted on Posted in minimum daily requirement, the Lab, The PositiveTagged

Ink, metal, chalk, or dye on paper, it is the paper that holds the “stuff of” and it also is the source of the light.

Albumin Printing: https://www.bostick-sullivan.com/product-category/alternative-process-kits/albumen-printing-process/

Or, albumin paper: https://analoginside.com/en/product/20-papeles-albuminados-85×11-216x277cm/

Unsensitized photo-paper: https://www.fotoimpex.com/brands/adox-art-baryta-241×305-cm-95×12-inch-50-sheets.html

Reflection requires smooth surface — smoother is more reflective. This provides higher “saturation” — the Dmax. The topmost covering produces the first and last light scatter. In photography of the Silver Gelatin type, this is Gelatin. Albumin has also been used. Many colloids have been tried in search of the perfect holder; that stuff with perfect properties — lasts, passes liquids, blocks gasses… No perfect single thing has been found — we live with a suited to purpose answer.

The ‘goo’ adds color– albumin is different color than gelatin. They age differently. As matter of cost,the albumen silver print uses more silver than the silver gelatin print

Make it smoother; get higher density. Gelatin seems our easy, cheap solution. That is what we have used at industrial scale since the 1930s. Keep the emulsion thin and smooth to achieve higher density.

The secret to Dye Transfer’s intense color isn’t due to the matrix nor the dyes but to the paper, one of the most protected secret of the process. That was the item causing Kodak to stumble in the 80s. The process of the mill was little understood by much of the Kodak elite.

Additional to coating is HOW you coat; the tool, coater, as well — how many coatings. Making the emulsion means controlling crystal size, dispersion and “layer” —

chemical photo: stuff

Posted on Posted in alt photo, art biz, The Negative, The PositiveTagged , , ,

January 2025. GETTING STUFF. supplies in a ebb market.

NOTES:
too much… getting too much.
choice must be clearly known to be choice.

Shops selling items for the darkroom.
In Germany, Hans O. Mahn GmbH & Co. KG brings out the Rollei products through the website Macodirect which also sells Adox products. The website Fotoimpex seems closely related to – and sells all – Adox products –does not sell Rollei papers

Stores:
the wet lab is drying out; few places remain, but here are some online sources

Prior Posts:

lab. 12/18 Fujifilm

Posted on Posted in labnotes, overnight notes, The Positive

What Fujifilm knows. Two interesting patents about color print/ display materials. Also contain light sources used during testing of the new material.

People. Patents. Products. Find the people behind the knowledge and you will learn what the product solves. Meindert Slagt has few patents. This one lists several people with multiple patents. Jun Matsumoto came about in reviewing other patents of the holders. He is a key researcher for Fujifilm. Finding the addresses of each of these researchers locates their research building.

The need to provide a different print material, one designed to solve the problems of prior silver/color printing in being used in a digital /scan printing system.

  • A: “light-sensitive material after digital exposure.”
  • B: “it is obvious, that in digital exposures other problems have to be solved to obtain a very good color photograph.”
  • C: “a high-quality image with higher desnity is requested for the transmission-type light-sensitive material.”
  • D: “if the difference in density is too small, it is difficult to obtain satisfactory image quality in the points such as black depth…” difference too higher, problems such as delay of development in lower layer(s)…
  • E: a snippet describing a single layer (the Fifth) of the display material. This is the Red-Sensitive layer. Notice that there are 5 Cyan couplers indicate, and eleven “color-image stabilizers.” Describing all the chemistry would take months.

>> https://patents.google.com/patent/US20060068338A1/en ” as to technique to prepare a color print, printings by both conventional surface exposure and scanning exposure have been practiced, and color print materials for each exclusive use have been put to practical use. Therefore, at the site of color print preparation, two kinds of color print materials are necessary. In the past there has been a vast amount of developments in order to improve the response to light of silver halide systems in order to obtain the best results upon analogue/surface exposure. ” Inventor Meindert Slagt Akira Kase Peter Franciscus Van Asten Yasuo Iwasa

>> https://patents.google.com/patent/US20040157175A1/en “As a method to expose a light-sensitive material according to digitized image information, an image-forming method in which scanning exposure is carried out using a light source of high light intensity such as a laser or LED, has been rapidly gaining popularity. Resulting from the recent popularization of laser printers and digital prints, the above-said image-forming method has been common. Accordingly, there has been a continual need for a light-sensitive material having characteristics suitable for laser exposure and digital exposure. As print for a display advertisement, higher image density is requested, because a vivid image must be provided from its purpose of use.” Jun Matsumoto Shinichi Nakahira Hidekazu Sakai

—- plus, updated posts: this on portra