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Two23
24-Mar-2011, 21:41
I am starting to shoot my Derogy during the day now, having made an f16 for it. I've been using Efke 25 and coated ND filters so I can have a 1s exposure. Looks like Efke 25 is the slowest b&w film available? How low can it be rated and still get decently good results? I'm assuming it can easily be shot at ISO 12?


Kent in SD

Vaughn
24-Mar-2011, 22:09
Most film can handle a stop over-exposed -- and if the contrast is high, then reducing the development will get you right where you want to be. YMMD

Jay DeFehr
24-Mar-2011, 23:21
I get EI 6-12 with ortho lith film.

Roger Cole
24-Mar-2011, 23:32
Efke IR with an opaque IR filter?

Also, I don't know what this thing actually is or the format, but how about paper negatives? There's a thread over in image sharing, and it seems that would be pretty slow.

If you REALLY need S-L-O-W you could use a paper negative of contact paper like Lodima. ;)

Two23
25-Mar-2011, 06:08
No, the Efke is the regular silver one from B&H. Comes in a box of 50, says PL 25 M on the box. The paper negs are something I really want to try at some point, but haven't got around to it. I need to read up on it. As I gain experience and confidence I like to try new things and increase my skills. At the moment I'm just wanting to experiment with the Efke 25 rated ISO 12, or can it go lower than that?


Kent in SD

Vaughn
25-Mar-2011, 07:38
If you want to get real low, try it at 6 or even 3. The negs will probably be very dense, but then bleach the negs and re-develop to the density you want. This can be done in room light. You could even partially bleach to get rid of some of the extra shadow detail first, re-fix, then do the above step.

What will the images look like? Heck I don't know, but it sounds like fun.

I have bleached negs to lower the shadow values, then selenium toned to boost the hightlights -- this was to boost contrast for alternative processes.

Of course you could always make a f64 stop for your lens.

Two23
25-Mar-2011, 08:01
Of course you could always make a f64 stop for your lens.

Thanks for the info. I probably will make some more washer-stops for my lens. It's a Derogy Petzval, and wide open shows more of the famous bokeh. Sometimes I do need more DoF though.


Kent in SD

Vaughn
25-Mar-2011, 08:22
Are you are looking for a 1 sec exposure time because you have no shutter? I run into that problem with my barrel lenses (RD Artars).

Andrew O'Neill
25-Mar-2011, 08:51
I shoot this in 4x5 and 8x10. 16 is my "normal" EI.

Two23
25-Mar-2011, 12:32
Are you are looking for a 1 sec exposure time because you have no shutter? I run into that problem with my barrel lenses (RD Artars).


Mainly, yes. Night time is no problem, but daytime is another matter. I also think long exposures help replicate the vintage look. It seems to soften things just a bit, somehow. Maybe it reduces contrast?



Kent in SD

Vaughn
25-Mar-2011, 13:15
The romantic part of me also feels that long exposure and the capturing of time somehow imparts something to an image beyond what we see. Of course the pragmatic part of me knows that I would be hard pressed to tell the difference between two otherwise identical images, one taken at 1/8 second and the other at 8 seconds.

But I ignore the pragmaticist most of the time. I am an artist, not a scientist, after all! LOL!

A back or front mounted packard shutter might be an answer. Some have an "instanteous" setting (1/125?) and I do not know how quickly one can open and close one of those manually...but it would be sub-second.

Roger Cole
25-Mar-2011, 13:42
Efke IR with an opaque IR filter?

Also, I don't know what this thing actually is or the format, but how about paper negatives? There's a thread over in image sharing, and it seems that would be pretty slow.

If you REALLY need S-L-O-W you could use a paper negative of contact paper like Lodima. ;)


No, the Efke is the regular silver one from B&H. Comes in a box of 50, says PL 25 M on the box. The paper negs are something I really want to try at some point, but haven't got around to it. I need to read up on it. As I gain experience and confidence I like to try new things and increase my skills. At the moment I'm just wanting to experiment with the Efke 25 rated ISO 12, or can it go lower than that?


Kent in SD

I think you misunderstood my reference to the IR. I knew you were shooting the regular stuff. I was suggesting shooting the IR with a visually opaque IR filter as a way of getting much, much slower. I think people usually rate this at EI 3 or 6, and I believe that's in sunlight. It would be a lot slower with other sources, possibly completely insensitive, but if you want really slow, it's another step down.

Tobias Key
25-Mar-2011, 14:01
Have you thought of using an ND400 filter? They are primarily for shooting solar eclipses and cut the light by 9 stops.