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Photo Engineer
04-07-2014, 09:15 PM
Film Needs about 300 mg / ft sq of silver, but paper needs 1/2 or less of that. This is the reason. You need dmax with film.

PE

GLSmyth
04-07-2014, 09:41 PM
Thanks, that makes sense.

Cheers -

george

Photo Engineer
04-08-2014, 11:38 AM
One additional thought though. Mark, Nick and I spent a day trying to coat plates with rods and found an unusual ripple effect on our plates. They are working on this and I have to go over again in a few days to continue this work with them. We hope to get a handle on it.

PE

Andrew O'Neill
04-08-2014, 03:23 PM
Actually, I push the gelatin around with my fingers now...

Resorting to a cheap accessory, I use a comb from the dollar store. :)

Photo Engineer
04-08-2014, 03:49 PM
This is excellent for the artsy look. We have done many things in our workshops at GEH.

However, nothing beats a blade or a rod for sheer quality. You can approach current production quality this way.

PE

dwross
04-08-2014, 04:57 PM
This is an interesting issue. I'd even go so far as to say "problematic". By now, it is indisputable that handmade silver gelatin can be made to a quality where you can't tell it from commercial. What do we get for that fact? A big "ho hum". ASA 100 ortho roll film: "ho hum de dum". But make an absolutely craptastic wet plate and the crowd goes wild. :laugh: If not for the fact that I'm a pathologically upbeat person , it would be depressing!

Maybe exactly what we need are more fingers and combs in the emulsion. Go for it, guys. Make a happy mess. You just might make a name for yourselves!

Photo Engineer
04-08-2014, 06:15 PM
You have a very good point Denise. And, a surprise to you I am sure, I agree.

However, in all of our workshops, we let students finger paint, use brushes, rods, blades and etc. Just about anything goes and on many paper types, but the preference is always either a blade or a rod due to quality. So, HO HUM they may be, they are desired.

PE

kb3lms
04-08-2014, 08:51 PM
A threaded steel rod from the hardware store will work, too. I prefer the one with the color coded green paint on the ends, IIRC it is 3/16 inch.

Jason

Photo Engineer
04-08-2014, 09:17 PM
Seems pretty heavy to me, but if it works, it works.

PE

Dr Croubie
04-09-2014, 12:06 AM
You have a very good point Denise. And, a surprise to you I am sure, I agree.

However, in all of our workshops, we let students finger paint, use brushes, rods, blades and etc. Just about anything goes and on many paper types, but the preference is always either a blade or a rod due to quality. So, HO HUM they may be, they are desired.

PE

There's a type of art that I've seen around occasionally, where you enlarge to paper normally, but then just splash developer over the paper so it doesn't cover the entirety, you just get a Rorschach-shaped image. (not sure if there's a named-style for this, like there is for something like a Photogram).

Maybe there's just as much artistic-merit in simply painting the emulsion onto the plate/paper before exposure? Depending on how gloopy and sticky it is, you might be able to get some nice shapes out of it.

Scratch that, forget what I wrote, noone steal my idea. I'm going to get a paintbrush and a bottle of liquid-light on the way home, and get practising my chinese calligraphy...

GLSmyth
04-09-2014, 07:29 AM
Actually, I have done the paint with developer thing a number of times. When sepia toned on matte paper it looks quite good. I also played around with applying developer with a spray gun so that it results in a series of dots, which is fun.

Cheers -

george

jnanian
04-09-2014, 07:51 AM
There's a type of art that I've seen around occasionally, where you enlarge to paper normally, but then just splash developer over the paper so it doesn't cover the entirety, you just get a Rorschach-shaped image. (not sure if there's a named-style for this, like there is for something like a Photogram).

Maybe there's just as much artistic-merit in simply painting the emulsion onto the plate/paper before exposure? Depending on how gloopy and sticky it is, you might be able to get some nice shapes out of it.

Scratch that, forget what I wrote, noone steal my idea. I'm going to get a paintbrush and a bottle of liquid-light on the way home, and get practising my chinese calligraphy...

hi dr c

with coating your own you have an open slate. its much more versatile
than pre bought papers &c ... once you understand how the emulsion sticks ( or doesn't )
or hardens, ( or doesn't ) or ? there are ways of doing all sorts of fun stuff ...

Photo Engineer
04-09-2014, 08:55 AM
I think that there is room for all of these. After all, it is art and just about anything goes. The questions are whether you like it and then whether your audience / customer(s) like it.

If it does not please the majority, then it is not what is going to be viable until after you die! :D this is the usual rule o art!

PE

Vaughn
04-09-2014, 11:26 AM
There's a type of art that I've seen around occasionally, where you enlarge to paper normally, but then just splash developer over the paper so it doesn't cover the entirety, you just get a Rorschach-shaped image. (not sure if there's a named-style for this, like there is for something like a Photogram).

Maybe there's just as much artistic-merit in simply painting the emulsion onto the plate/paper before exposure? Depending on how gloopy and sticky it is, you might be able to get some nice shapes out of it.

Scratch that, forget what I wrote, noone steal my idea. I'm going to get a paintbrush and a bottle of liquid-light on the way home, and get practising my chinese calligraphy...

Sometimes it is fun. Platinum print, 11x14 negative. Next time I'll keep Alex's feet in the image area!

Athiril
04-10-2014, 11:51 PM
Hi Athiril,
Thanks for looking up the numbers on tape! Scotch Magic is a easy candidate for taping puddle pushers. For some reason I've totally forgotten, I had a couple of rolls of 850 when I started playing with emulsions and I settled into it as my tape of choice.

One note: 0.9 mil of the 850 is the adhesive. That's one reason I like the stuff so much. I just count each wrap as 1 mil because I assume the adhesive mashes down to nearly nothing. I also have to assume the adhesive on Magic Tape is also about 0.9 mils. But, as said, "stressing the mils" isn't necessary. Vaughn's approach to carbon could be the role model for our work. He's a master of his craft, without resorting to expensive accessories.

Customer service for 3M got back to me, as I also sent the question to them.

They're stating 810 magic tape is 2.2 mils (0.056mm) instead of what I found in the data sheet I found. I guess if you want to be specific, you should measure the rod bare, and then with the tape on.

dwross
04-11-2014, 08:41 AM
Thanks for digging up the information. That puts Magic Tape even closer to 810. They certainly look like they are twins, side-by-side. 3 mils is about as thick as air. Really, though, the exact mils is not that important a variable. I use the same puddle pushers for all my coating. 10 wraps of 850 tape. Might be eleven or twelve on one of them. (I have five so that I can coat five 36" strips of film in one coating session, without stopping to clean them before I'm done. With film, starting with a dry puddle pusher improves the quality of the coating pass. With paper, it's not as important.)

Anyway, what's important is the temperature of the emulsion while you coat. One degree C can make a difference there. It's all about viscosity. The lower you can go and still have a good, smooth flowing emulsion, the better the density and contrast in the final product (permanent caveat: "in my experience".)