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-   -   Static 35mm Adapter Solution (https://www.dvinfo.net/forum/alternative-imaging-methods/18690-static-35mm-adapter-solution.html)

Ernest Acosta January 12th, 2004 12:31 PM

Great Work
 
Great work folks! Vendible I've been following your idea from the Agus35 posts. I also own a DVX100 and pending your experiment on the 10 degrees Holo diffuser, I will place an order for two.

Frank Roberts January 13th, 2004 10:08 AM

To Lewis...
 
Lewis, in regards to your holographic material, and forgive me if this had been covered in another post, is there any way to introduce illumination to it? I.E. It is isolated somewhat from the prisms, correct? Is there anyway to expose only the holographic material to illumination of some sort. Just curious. Best- Mike

Filip Kovcin January 14th, 2004 03:46 PM

to daniel moloko
 
hey, daniel!

did you finally find that guy who has a shop with full of old zenits?

did you find the exact model where from yo tooked your GG with no grain?

filip

p.s.

need this info desperatelly!!!

Frank Roberts January 14th, 2004 04:11 PM

What about this?
 
Beattie bright screen.

http://www.tallyns.com/Beattie.htm

Dean Harrington January 14th, 2004 06:34 PM

Frank....
 
the beattie screen looks interesting. I've asked them about the size and micron thickness.

Mark Beal January 16th, 2004 01:08 PM

<the beattie screen looks interesting. I've asked them about the size and micron thickness.>

I just pulled the focusing screen out of our Hassalblaad, and it's 2 1/4 x 2 1/4". I'm not sure about the thickness, but it's about like an acrylic lens filter. The Beattie screan should be about the same.

Dean Harrington January 16th, 2004 02:55 PM

Mark....
 
That's about the same size as the holo. if it's about the same thickness as an acrylic lense - I'm going to guess about 3 microns? Mark - does that sound right?

Filip Kovcin January 19th, 2004 05:47 PM

louis,

did you finished your holo35?
any news, any photos?

just curious

filip

Brett Erskine January 20th, 2004 02:02 AM

Apochomatic Lens for homemade Mini35
 
Hello everyone. Until not too long ago I thought I was the only one that had tried to build my own Mini35. When I found this thread I was inspired to get working on the project again. Its nice to see there are more people putting their heads together on this problem. Because I wasnt bouncing my ideas off of anyone my design has evolved totally seperate from you guys and while we have gone down similar designs paths I thought I would bring up some things that have been totally over looked and sooner or later we are all going to have to deal with if we are striving for perfect looking footage:

1) Apochomatic Lens - for just about anyone planing to use a 3CCD video camera other than a XL1 your most likely going to need some form of a diopter/closeup filter lens in order to both keep in focus and fill the frame of our target object size: a 35mm film gate (same size as the inside of a individual film slide mount).

But two problems arise when focusing on something so close to the cameras lens.

Spherical and chromatic aberration.

Spherical aberration is the barrel effect you see exagerated on extremely wide angle lenses where straight vertical and horizontal lines of a given subject are bent outward as they approach the outside edges of the frame (fisheye effect). Your going to see the same unwanted effect (although to a lesser degree) when you try to capture that image projected on the ground glass. Try shooting a grid with your current homemade mini35 setup and you'll see what Im talking about.

And if you look real closely you will also notice the effect of something called chromatic aberration at the outer edges of the frame as well. Its characterized by the bleeded and blending of colors along with a over all ever so slight out of focus appearence. Technically speaking this is due to how different wavelengths (colors) of light react and bend at slightly different degrees as they go thru glass (ie a prism's rainbow)

But dont worry. Im not only the bringer of bad news but good as well because both can be corrected for with prefection with what is known as a APOSPHERICAL compound lens.

Which brings me to one of the reason why I temporarily dropped the idea of making my own a long time ago. I can't seem to find someone that manufactures exact what we need:

-----------a APOSPHERCIAL Macro Lens------------

In my case one with a +10 to +12 power because I have the DVX100.

So I hoped we could put our heads and resources together to find one. I tried Edmunds Scientific. Nothing. Anyone have any other links?

Brett Erskine
Director of Photography
Premiere Visions

Taylor Moore January 20th, 2004 02:07 AM

Hi Brett,
I have started a post over at

http://www.dvxuser.com/cgi-bin/DVX/YaBB.cgi?board=news;action=display;num=1070228577

there is a fellow from Century optics who has put up some specific information relating to the dvx and correct lens.

Hope this helps.

Brett Erskine January 20th, 2004 02:08 AM

APOCHROMATIC Macro Lens for homemade Mini35
 
ha ha I ment to say we needed a:

APOCHROMATIC Macro Lens

not a apospherical.

-Brett Erskine

Nicholi Brossia January 20th, 2004 04:27 PM

Some folks were using, or planning on using, Century Optics' achromatic diopters. The apochromatic are basically a step above achromatic. Just so everyone can understand exactly what these lenses accomplish, here's a link: http://hyperphysics.phy-astr.gsu.edu...opt/aber2.html.

James Ball January 20th, 2004 10:36 PM

"When we speak of
 
"When we speak of correcting chromatic aberration, the term should not be taken literally, as meaning "eliminate," but should be understood more in the sense of "suppress." from the link below:

http://www.astronomysite.com/mapug/13/msg13371.htm

This guy tells the differences between apochromatic and achromatic with a discussion of is it "worth" the extra$. It's for telescopes but is salient.

He also discusses 3 element acromats (l think Edmund has these)

Dean Harrington January 21st, 2004 07:20 AM

apromatic lense....
 
Since it seems that the blue spectrum aberrance effects the image would an 85B filter in front of a acromatic lense work to correct the light?

Anders Floe January 23rd, 2004 02:46 AM

GG
 
I looked at the movietube construction and saw that it uses a special developed microcrystalline grain glass as ground glass. Couldn't we use a normal piece of glass and wax it with microcrystalline wax to get almost the same effect? Just an idea.


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