new idea for GG (maybe?)

[Filip Kovcin]

idea:

use unexposed 35mm negative film and find kind of "wrong" processing (developing, fixing etc.) to acheive plain "milk"white surface. but still semi transparent.

i do not know how to do this right now, but i remember when i was developing my old b/w photo negatives, from time to time i did something wrong with temperature, timing or/and chemicals and received parts of negative wrongly developed. and they were often king of pale green???

i belieive that with proper method - there is possibility to receive nice white/milk surface.

since film grain is VERY small - if you use, say 50 asa film - there is a chance to make proper GG with a grain smaller than any CCD, even HD...

and if this is possible at all - and you receive proper 35mm GG - just cut it and glue it on plain glass. with the rest of your negative 35mm GG frames you can do whatever you want - even to send it to other users of this respectable forum.

just an idea... i hope,


filip

[Laurence Maher]

I'm a layman, I guess, but what would be the point of this experiment. Can I ask what you're trying to achieve?

[Bob Hart]

I have seen something like that, a very long time ago, on some old glass photographic plates which had been left out in the weather on a dump. As a kid, I had no idea of their value from a historical point of view, all cityscapes and picket fences.

I wonder if an emulsion, not necessarily photographic, could be applied to glass then processed to produce this outcome, then covered with another sheet of glass to protect the surface. It would be another form of the Boss screen but might be viable.

[James Ball]

use slide film and shoot a solid neutral gray that is evenly lit. Shoot out a variety of grays.

If you have an LCD display use photoshop and fill a .jpg with various gray values. Enlarge to fit the screen. Back off 3 feet, zoom in to fill your viewer with the screen. Turn off the lights, close curtains. Set the exposure, defocus a little.

I'd say it's worth a try.

The diffusing layer should be very thin!

[Laurence Maher]

uhhhhh,

Can I ask what you're trying to achieve?

just curious . . . I'm at a loss.

[Frank Ladner]

Laurence:

Filip is suggesting an alternative to the larger-grain ground glass as an intermediate image collection surface.

The static and rotating 35mm adapters (homemade Mini35s) have been using ground glass (or plastic). The surface is ground with aluminum oxide (usually 5 micron or so...pretty fine grain) or some other abrasive so as to create a 'frosted' surface that, when you put it behind a 35mm lens, you can see the image projected onto it. Then you basically record this image onto your DV camera (usually with a macro lens inbetween there).

Well...on the static (non-rotating/vibrating) models, the grain is still evident, especially if you stop down the 35mm lens. The next best thing is likely microcrystalline wax, which is supposedly microscopic-fine.

So...as Filip says, with a translucent 35mm negative processed the way he describes, it may replace the ground glass solution, since 35mm film has way smaller grain.

Hope this helps! Let me know if I didn't explain something right. :-)


,Frank

[Filip Kovcin]

if i'm not wrong with this idea - if you use wrongly developed (which means that this frame is evenly frosted after that "wrong" process) single frame of 35mm negative you can use it instead of sand grid GG. if this is possible at all - just treat it as another solution INSTEAD of normal GG for aldu/agus device.


filip


p.s. btw - i do not think that grey slide frame (normally shooted and developed) will work - because it will be treated as kind of neutral density filter, which has color (grey in this case), but it will be fully transparent, (like ND3, ND6 or ND9 filters) but darker, not "frosted".

[Ari Shomair]

Why aren't 35mm SLR Focusing screens used? They already have condesors in them, making them good candidates. They can also be purchased which have no marking;

do they have a visible grain?

[Frank Ladner]

Ari: Yeah, 35mm focusing screens are ideal in that they are designed to distribute the light more evenly, cutting out the hot-spot problem. But, as you guessed, they do have visible grain.

[Ari Shomair]

What if we were to vibrate them?

[Frank Ladner]

Ari: Vibrating / rotating / moving the ground glass in some way does practically eliminate the grain/patterns because it is moving and thus the grain isn't still long enough for the camera to pick up.

Check out some of the other threads here to see what people are designing in the area of non-static 35mm adapters.

,Frank

[Cody Dulock]

anybody tried using frosted glass spray??? duno if it would work or not.... just a thought

[Aaron Shaw]

What is frosted glass spray?

[Cody Dulock]

theres some pictures of glass that has been frosted...

http://www.diynet.com/diy/gl_etched/article/0,2025,DIY_13838_2273960,00.html

frosted glass spray is like a spray paint

http://www.lowes.com/lkn?action=productDetail&productId=102170-000000090-1903-830

[Jim Lafferty]

It doesn't work -- the grains are far too large.