Material for focusing Screen in a 35mm DIY adapter

[drjass]

What materials can be used as Focusing Screen besides the normal Canon/Nikon screens and the wax screen???

 

[Ted Ramasola]

frosted CDs or frosted CD cases for a spinning set up, not the vibrating type.

 

[Pettersen]

For my adapter, I actually used a laminating pouch like this.

I cut it in shape of a cd, and it works great in my rotating design. If anyone is interested, I have some footage I can post. I just have to upload it first.

 

[Park Edwards]

i wouldn't mind seeing it.
i remember using some of that a long time ago, but never got around to it.
how did you mount such flimsy material on a spinner?

 

[Pettersen]

Here is the test.

I just cut a hole in the middle and mounted it like a CD. The G-force from the spinning keeps it in place.

 

[rafikiwilliams]

pettersen what kind of set up are you running? that footage looked great.

 

[rafikiwilliams]

ah so i see your setup here

http://norskfilmforum.com/modules.php?name=Forums&file=viewtopic&t=4821

as its in Norwegian i cant read it but, my only real question is, did you use a macro for your dvx? and how did you get rid of vignetting?

i have a homebuilt static adapter, but the vignetting is pretty bad, and advice? thanks

 

[Pettersen]

It's a diy rotating design. Even though the footage looks OK, the adapter makes a lot of noice so it's not that great to use on set. I've ordered an SGpro that I'll probably get in a few days.

Here are some pics of the adapter:

I've tried a lot of different GG solutions, and found this to be the best. Earlier I used a hand-grinded CD, but the light loss and grain was quite bad.

The motor is from a discman (not sure what brand). It's powered by a 9v battery.

The achromat is also DIY. Made out of two binocular front elements.

You can see more from my adapter here, here and here.

 

[drjass]

Thank you, man! your footage looks great! Im going to get one laminating pouch. Im working in a DIY vibrating project and I need something like that.

 

[leteeci]

Hey!

If this laminating pouch is tin foil, you can use the old Floppy drive and huck it to adapter.. They are cheap.. And you can put foil in old Floppy discetes, and have diferent grades of GG, which can be switched in seconds..

Just idea..

Cheers

 

[Kevin Lee]

Petterson, I am really interested in building an adapter like yours. So the laminating pouch is laminated together on itself and provides a clean GG surface?

 

[Pettersen]

Not sure what you mean by "laminated together on itself". The laminating pouch has not been put through a laminating machine, if that's what you mean. I can actually pull the pouch apart into two separate layers, but they haven't separated while spinning (yet). I don't think they will, either.

Good luck on building your own If anyone is interested, I have some more pics of the adapter and the achromat that I can post.

 

[Park Edwards]

how did you mount such flimsy material and keep it from wobbling?

 

[Pettersen]

I cut a hole in it and mounted it like an ordinary CD. It wobbles a tiny bit, but I haven't had any problems with picture going out of focus, etc. The g-force keeps it level when the adapter is mounted on a tripod, so the only situation where wobbling could be a problem, is when doing quick pans. I haven't experienced this, though.

 

[Park Edwards]

interesting. i figured it would wobble and throw the flange distance off. thanks for sharing.

 

[Pettersen]

I was worried about that, too, but it seems to work good.