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-   -   35mm Adapter Static Aldu35 (https://www.dvinfo.net/forum/alternative-imaging-methods/20408-35mm-adapter-static-aldu35.html)

Mike Tesh February 3rd, 2004 03:31 PM

Brett where do you get one of these regular condenser lenses and about what do they cost?

Frank Ladner February 3rd, 2004 03:40 PM

Brett: This makes sense, with the condenser being curved on one side and flat on the other. The curved side would pick up the image and project it out straight.

What would the correct condenser size be for the given filter size? ie. should it be equal to or larger than the filter?

Thanks for this suggestion!

,Frank

Jim Lafferty February 3rd, 2004 06:21 PM

I'm just stopping in to see what people are thinking about the LCD monitor issue. I think the previous link had only one among all the options available that advertised its ability to "inverse" the image. This makes me skeptical about purchasing a lot of the models out there.

For instance, here are two I've found that would otherwise seem promising, but I don't know whether or not they can rotate and flip the image:

One.

Two.

Does anyone here have a sufficiently comprehensive understanding of electronics so as to share how you could jury-rig a monitor with an inverse and rotated image? Is it a matter of just swapping inputs?

- jim

Brett Erskine February 3rd, 2004 08:48 PM

As far as what, how much and where of condensor lenses just read my previous post again. All the answers are there.

For CRT's only I would have to say yes you can switch certain wires to flip the image but your likely to get a SERIOUS maybe even deadly shock for your troubles. Wouldnt help anyways. We need LCDs for this app. Like most of the questions just take the time to look at my previous post but I'll give you the link again anyways. These will do what you need:

http://www.portablemp3playerstore.com/

They are also on ebay all the time for cheap. Look for "sunvisor style" LCD screens.

Brett Erskine
Director of Photography
Premiere Visions
1761 W. La Palma Ave., Suite #302
Anaheim, CA 92801
www.CinematographerReels.com
BErskine@CinematographerReels.com

Jim Lafferty February 3rd, 2004 09:02 PM

Brett,

Thanks for your response, though in case you missed it, this link you provide is exactly what I've first linked above. To reiterate -- among all the models of LCD screens listed only one boasts of being capable of inversing an image.

I'm not about to shell out the dough to get a different (read: cheaper, smaller) model and risk it not having this feature.

- jim

Frank Ladner February 3rd, 2004 09:05 PM

I spent about 40 minutes grinding my uv filter on 600 grit aluminum oxide today and the results are excellent. I get a very fine grain glass that is uniform in brightness (no hot spots).

After testing it a bit on my GL2, I see that I badly need a condenser or some other solution. (The center of the image is very nice and sharp, though.)
So I have called around and have someone that is gonna bring me an old slr body tomorrow. If the condenser or something from that doesn't work, I guess I'll have to order a condenser, but I'll try and let you guys know what happens.

Thanks to all of you for posting your suggestions!

,Frank

Brett Erskine February 3rd, 2004 09:36 PM

Heres my "PremiereVisions35 adapter" (ha ha or whatever you would call it) design equation:

35mm lens>condensor lens>600+ alum. powder ground glass or better>macro lens (+16 power*)>video camera with on board image flipable LCD

(*for DVX100. May be different power for other cameras)

And if you want to have the image interially optically flip and mirror without the aid of a extra LCD the equation is:

35mm lens>condensor lens>600+ alum. powder ground glass or better>Pechan prism>roof pentaprism>macro lens (+16 power*)>video camera

Brett Erskine
Director of Photography
Premiere Visions
1761 W. La Palma Ave., Suite #302
Anaheim, CA 92801
www.CinematographerReels.com
BErskine@CinematographerReels.com

Mike Tesh February 3rd, 2004 10:10 PM

My 35mm Minolta SLR didn't have a condenser lens unless it was built into one of the prisms or the ground glass. The Ground glass (plastic) actually looked more like a fresnal. It won't work though. So I need to find a condenser lens somewhere else.

Paul Doss February 4th, 2004 09:44 AM

Alain,

Just watched the lastest footage. Very nice. I can't get over the very shallow depth of field. In the shot with the guitar only 4 or 5 frets are in focus. Never thought I'd say this but, almost too shallow for many applications.

Was the aperture wide open? Any chance we could see some footage shot in bright lights or outdoors?

Paul
dvdof.com

Stewart McDonald February 4th, 2004 10:45 AM

Depth of field gets shallower the closer you are to the subject, I think.

Taylor Moore February 4th, 2004 10:51 AM

DOF
 
Not to get off the focus of this forum but depth of field is dependent on light/shutter speed and aperature.

More light--less softness
Less light--more sharpness

THe B.S. algorithym for depth of field is approx 1/3 soft before focal plane(place of focus) 2/3 soft after focal plane.

This is a rough layman explanation.

Barry Green February 4th, 2004 01:12 PM

<<<-- Originally posted by Stewart McDonald : Depth of field gets shallower the closer you are to the subject, I think. -->>>

That is correct -- distance to subject is a major factor in determining DOF, and the closer you are, the shallower it is.

For shallower DOF, you need to get as close to the subject as you can, use as wide-open an iris as you can, and as telephoto a lens as you can.

Kyle Doris February 4th, 2004 11:22 PM

"35mm lens>condensor lens>600+ alum. powder ground glass or better>Pechan prism>roof pentaprism>macro lens (+16 power*)>video camera"

will this have to be tweaked with a DVX-100A, due to the different minimum focus length (2' instead of 3' i believe) or does it not matter?

thanks in advance.

-kd

Brett Erskine February 5th, 2004 12:01 AM

Yes. You wont need a diopter quiet as powerful for the DVX100-a. I'd love to confirm thoughs minimum focus numbers. Find out what they are and its simple math after that.

Alain Dumais February 6th, 2004 11:01 AM

Frank
 
------I spent about 40 minutes grinding my uv filter on 600 grit aluminum oxide today and the results are excellent. I get a very fine grain glass that is uniform in brightness (no hot spots).------

I am doing another GG today and after a hour I am about alfway to the final result and the last part are longer.

What I have actually is about two time the size of the grain that it as to be ,otherwise I will see the grain.

I was thinking that maybe your gg is made from plastic, there is some uv filter that are made whit plastic and this very easy to grind but also easy to scrath. But easy to repare.


Alain


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