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-   -   Mini 35 Competing Unit for a Lot Less $ (https://www.dvinfo.net/forum/techniques-independent-production/10532-mini-35-competing-unit-lot-less.html)

Spencer Houck July 11th, 2003 12:12 PM

I love that image, absolutely great!

I'm a very uninformed "noob" if you will, but I keep hearing people say that the 35 mill conversion doesn't work well with cameras with permanent lenses, such as your GL2 and my VX2000. Your tests seem to put that thought to shame, and I hope the same can be attained by my VX noting our similar lens setups.

Knowing that I'm totally uninformed, in theory could we in effect cancel out that we have lenses in front of our cameras? Bear with me now, but could you replicate the permanent lens structure of our cams in reverse and toss it in front of our cameras to take us down to a sort of "glassless state" like the Xl1? It seems a little fantastical and may introduce color abberations, etc., or maybe it just doesn't make any logical sense at all, but it just sounds like it may be crazy enough to work to someone who's clueless :). Who knows, maybe with your setup the glass in front of my camera won't instigate a problem, I'll just have to test and find out.

Oh yeah, I can't see very well what the philatelic lens(5x) looks like in your setup picture. Can you explain that to me, is it just a normal magnifying glass like any one you'd find?

Thanks for keeping the innovative stuff alive,
Spencer Houck

John Jay July 11th, 2003 02:08 PM

eureka or maybe countach!


1 was the fresnel still necessary?

2 looks like I shall find a new use for the lenses from my Pentax LX kit :)

Jaime Roman July 11th, 2003 10:09 PM

Hey cosmin,

How did you invert your image? Did you do this in post or did you use prisms?

I took a canon eos camera apart and am using a skeletal version of it; problem is i didn't realize that canon eos lenses do not have a diagphram control it is controlled by the camera body (which i just finished destroying, UGH!) do these lenses default to being wide open? Or, will i be destroying a perfectly good lens?

Cosmin Rotaru July 14th, 2003 03:34 AM

Hi guys!

Spencer, why do you need that "glassless state" for your VX2000? Al you need is to focus the camcorder lenses onto the 35mm GG. For this you need a close up lens: a normal magnifying glass.

John, in this second test I didn't use a fresnell lens. The image is cropped on top and bottom (for a 16:9 or whatever look) and so the corners are left out. And so is the vigneting!

Jaime, I inverted the image in post. I don't have a prism. I don't know about the EOS lens. The lenses I use (Pentax K-mount?!) are wide open by default. The lens has a small lever that goes from the lens in the camera. Whatever aperture you chose, the lens stays open until you take the pic. Than the aperture is closed at the chosen level by switching that lever on the lens (yes, the camera does that). You can turn that lever by hand and see how the iris closes. I don't know if this is the case with the EOS lenses.

Spencer Houck July 14th, 2003 06:56 AM

Could you post some pictures of your newly updated rig, especially any with the camera set up on it also?

I seem to have a hard time focusing my camera on anything relatively close which is discouraging me a lot in recreating this great effect. I believe the GL2's minimum focusing distance is much shorter than my VX2000's. Hopefully I can get it all working.

Spencer Houck

Cosmin Rotaru July 14th, 2003 08:11 AM

I'll see what I can do so I can take a pic "with the camera set up on" the rig.
The problem is that I use the camcorder to take the pics...
You'll see that the GG is not very close to the camcorder's lens. Look again at the pics I've already posted. Is the same setup but I use the rotating CD instead of the GG/fresnel sandwich. The magnifying glass allows zooming in the GG.

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