Recent content by dwross

Crystal violet (also called gentian violet or methyl violet) plus methylene blue, were the dyes used for purple potato starch granules. Orange was a combination of yellow tartrazine with rose Bengal and eosin. (The Lumiere Autochrome, History, Technology, and Preservation, by Bertrand Lavedrine...

I couldn't agree more about bringing us closer to the true essence of photography. To realize that a photon can strike a silver halide molecule, and change its state to produce a fixed record of an object in one time and space, stills gives me goosebumps.

Peter, you are most definitely one of the Keepers of Light. The book of that title is what started me on my journey. Back then, silver gelatin wasn't an alternative :-). I did albumen for years. I guess I love glossy silver! It is amazing how far we've taken the historical and the new-alt...

I've never found one. Unfortunately, not all dyes are photosensitizers. Gentian violet was used to dye the purple potato starch particles in autochromes, but I don't think it was used as a sensitizer. Do you have an alternative/historical process chemistry supplier available to you? They might...

Interesting recipe. I don't see any obvious reason it wouldn't work, although I don't have personal experience with sodium acetate. Any recipe that can be coated on glass can be coated on paper, but its utility probably depends on whether you want paper negatives or printing paper for contact...

I think I have a selfie that looks something like that :-)

No need for expensive dopants. Keep it simple (and cool). Edward Curtis and others used the then-new photographic technology of silver gelatin dry plates to travel the American West without the portable darkroom required for wet plates. If you don't let your unexposed and exposed plates get...

Brain burp deleted.

I am unaware of anyone making color emulsion. However, it is very do'able to make BW ortho and panchromatic emulsions and then the various processes that use them. If this interests you, let the community know and we can get you started. Good luck and fun!

Learning to make and coat a simple emulsion is necessarily the first step. It's not hard. Second, expose and process your plates or film. You might enjoy the basic process for what it offers. A colorblind emulsion is unlike anything you can buy commercially. You might explore extreme halation...

Looking forward to your results!

I still do on occasion. I used to as a matter of course. I just use regular film. Finer grain film works a bit cleaner.

What you've observed is actually the miracle that is gelatin as a matrix. Once dry, it's tough. You might try something like emulsion transfer. If emulsion is coated on Yupo synthetic watercolor paper (actually, a plastic), it sticks long enough to get through the processing and then, before it...

Good luck! One last point. Barium sulfate is a fine powder. By itself it isn't a coating. It is applied to paper in a suspension of either gelatin or casein, along with various other ingredients. There isn't a surface that is "only baryta."

Hi Frederica. Welcome to Photrio! Always great to see new alt process photographers. I'm sure I'm not the only one interested in the details of the process/question you are researching. The more information, the better the membership can help you. There is a LOT of experience represented on...