Digital Negatives

[titrisol]

Thanks to Brazile for his comment in my thread a few weeks ago I began looking into printing those old photos into cyanotypes
It seems to me that the most important step is making digital negatives that match the tonal range of the final medium

I found these posts about it:
https://www.alternativephotography.com/ ... ives-gimp/
https://www.mikeware.co.uk/downloads/DiginegWork.pdf

But I still would like to know how are you guys doing this?
How to match the tonal ranges of the inkjet to the final print?
Wouldnt it be a lot of nano-dots in patterns that look like gray?

How if we use color in the negatives to block UV light more efficiently?

[Brazile]

See my post in your other thread for my answer to most of these questions. As to "nano-dots", no, the resolution of modern inkjet printers is sufficiently fine that once passed through the analog process of your choice, the dots are not really visible any longer. That said, I can see how applying the necessary curve to the image can yield some odd results that might result in banding, but in practice I haven't had a problem with this...so far.

As mentioned elsewhere, you can certainly discover which color in your inkset (I have an Epson 2880 printer, which uses the "Ultrachrome K3" inkset, I believe) to block UV, but it isn't necessary to start.

Robert

[Brazile]

Just looked at Mike Ware's notes. The man certainly knows what he's talking about, so I'm sure his method works. Interesting that he finds that an overall gamma correction (as opposed to calculating a specific curve from what amounts to simple densitometry) works for the purpose well enough, after having spent more time than I figuring out max ink.

I will note, though, that the process I use does not involve a 100-step wedge, but one of only 10 or 12 steps (can't recall just this moment) and it doesn't take that long to do. But Dr. Ware's method is also pretty simple and would be worth trying, and might yield better results.

Robert

[titrisol]

I went with Dr Ware's process, I'm using some Photographers Forulary liquid cyano... as I found a kit on sale
I printed a 31 step tablet and seems to me that I have to make the negatives with a Gamma of 1.8 - 2.0 so as to print in Grade 0 paper (soft)
The highlights are extended, and the shadows tend to compress

I made a 1st batch of 6 paper sheets on Canson water paper and results are decent.
Last night I prepared a 2nd batch; adding K-Drichromate to see if there is any difference

[titrisol]

I followed the procedure frm Mike Ware, and I had this picture that I have loved for a while
Looking outside the Opera House of Paris... dec 2009
Taken with a Pentax ZX7 and Fuji Film

Paris-Opera

Paris Opera House -Cyano[/url]
Paper: Canson Montval
Cyanotype - Photographers Formulary (2 coats)
Exposition ~45 min

[PFMcFarland]

That looks pretty good, Pablo. I'll have to read up on how you did it when it's not so late at night.

PF

[alexvaras]

The ones I saw in flickr are very nice!

[titrisol]

They are all the same process, after the negatives were made, basically using a Gamma of 1.8 I printed them (black) in transparencies and contact printed
The main problem is separating the tones in zones 2-4 and 7-9 which can be achieved with a curve such as:
Input 0 4 8 12 25 39 52 76 102 127 153 178 204 229 242 255
Output 0 84 112 126 145 155 162 171 179 186 192 197 202 208 214 225

The cyanotype was traditional chemistry (PF kit) I added the solutions with a brush, letting the 1st coat dry and adding a 2nd coat.
PF has K-Dichromate as part of the kit, and I used it in some of the tests as it is supposed to help with contrast
You can see the difference in the blue tone with 1 and 2 coats in this picture as you can see the difference in the edges where there are brushtroke marks
The 2nd coat makes the blue deeper

Development was in vinegar solution (1+1) and the water rinse

I used Canson XL paper for the 1st batch, and since ACMoore is closing, I got some nicer Canson paper (Montval) for the next batch (Opera picture) the tone is bluer and I heard toning is easier, so I'll try that but the texture is a lot more aggresive