View Full Version : Optosigma or Nikon D


DJ Lewis
December 19th, 2005, 10:41 AM
Hi,
was wondering what everyone thought was the better option. The Optosigma gg or a Nikon D screen?

I thoght about using two optosigmas back to back to get rid of the aerial image. (It would be used in controlled lighting situations, so there would be plenty of light.) But there is tons of talk about the Nikon D screen, but all the shots I look at seem to have some color fringing, and look a bit weird in the bright spots (or am I imagining this?)

I guess my overall concerns are with the color fringing and haziness that I see alot of... should I just break down and try to make a wak or bosscreen difusser?

Or buy a G35? :)

Ben Winter
December 19th, 2005, 12:48 PM
I would tell you to sandwich two optosigma GG pieces. I would only use the Nikon D in a non-static situation, i.e. dissassemble it and replace the Letus GG with the Nikon GG.

Andy Gordon
December 19th, 2005, 06:15 PM
I've tried Optosigma, Nikon D and 2x Optosigma. Nikon D is by far the worst, lots of grain and hotspot, smaller image area. 2 Optosigmas lose a fair bit of light and I think the grain may be worse than a single Optosigma, but I didn't test it much as the light loss was too much for me.

DJ Lewis
December 20th, 2005, 12:07 PM
how much light loss are we talking about here? Is it a night and day diffrence? (no pun intended).

Andy Gordon
December 22nd, 2005, 05:22 AM
I had another look at the double Optosigma after my latest attempt at a wax glass, and the light loss and grain on the double OS are better than what I can get with a 2 aluminium foil thick micro wax layer. If you use 2 120FL Optosigma PCX lenses you can eliminate the hotspot with very little if any colour fringing. I've played around with various arrangements on the condensers, PCX GG GG PCX (||) works, so does GG GG PCX PCX ||(), which would be better using a DCX to eliminate the glass air glass interface in the middle. There's also virtually zero barrel distortion, that's with a Takumar 1.4 lens on a GS400.

Anyways of everything I've tried the double OS is the best static solution so far, better than Beattie or Nikon D. I still haven't been able to make a wax glass without really obvious grain on it...

DJ Lewis
December 23rd, 2005, 12:18 PM
Andy, got any frame grabs of your adapter with two Optos and two pcxs? And what achromat are you using?

Andy Gordon
December 23rd, 2005, 08:03 PM
I'll try and post some grabs comparing my latest wax attempt vs 2x OS if I get the chance. You don't need an achromat with the GS400.