Hey all, I'm currently shooting with a kodak 2D and boy is that screen dark! I was wondering if there are any inexpensive methods of lightening the glass?
Hey all, I'm currently shooting with a kodak 2D and boy is that screen dark! I was wondering if there are any inexpensive methods of lightening the glass?
There have been a couple of recent threads about using the very inexpensive page magnifiers for Office Depot or Walmart as Fresnels to brighten the existing screen. I did it on my Kodak Master 8x10 with huge success.
Just cut it to size and place behind the existing glass. I used a band saw to cut mine, but some have mentioned using scissors.
"One of the greatest necessities in America is to discover creative solitude." Carl Sandburg
First get a more modern GG and then add a modern fresnel.
Faster lens?
More seriously on the inexpensive side, I'd do search on Fresnel lenses on the site & on google as that's about the only cheap way I'm familiar with.
4x5 and a Tessar is heaven
"I beg to dream and differ from the hollow lies..." Green Day
Have to agree with Bob, a new screen can make a big difference, then the fresnel gives a further overall boost. My own experience is the equivalent of over 3˝ stops improvement is easily possible compared to an old original glass screen.
The UK importers of Beattie screens claim 5 stops, but I think that's rather over optimistic, I do have a new Beattie screen on a 10x8 and can test that out for myself when next in the UK as I have 2 cameras and can swap the backs. Visually it's nothing near that figure, but I have good bright glass screens.
Ian
Has anyone had any experience re-grinding the screens in old Crown/Speed graphics? I have a couple graflok backs from this era, with fresnels, and I feel like they could be brighter. After reading the thread about grinding your own ground glass from scratch, I've been wondering if going after my current glass with 400-600 grit SiC would make an improvement or not.
Science is what we understand well enough to explain to a computer. Art is everything else we do.
--A=B by Petkovšek et. al.
I've made about 20 screens now, that includes 3 Speed/Crown Graphics and 4 German 9x12 cameras (almost the same size just a touch narrower).
All the screens are substantially brighter than the originals, and also slightly better than a commercial screen I bought 2 or 3 years ago.
In some cases I re-ground the originals, it makes no difference to the end result.
Ian
Good; I just figured it would be easier to re-grind the original than to get a piece of glass the same size. What type of grinding compound do you use? I've been told 400 grit SiC paste is the best to use.In some cases I re-ground the originals, it makes no difference to the end result.
Science is what we understand well enough to explain to a computer. Art is everything else we do.
--A=B by Petkovšek et. al.
I understand SiCarbide is the next hardest to diamond, I had trouble with it chipping the glass surface, rather than grinding it... Aluminum oxide leaves a much more even and smooth surface. Al oxide is used after the Si when lapping telescope mirrors. The stuff I have is made by Willmann-Bell, Inc, Richmond, Va 804-320-7016 It comes in a # of micron sizes. I start with 15 and go to 9, 5 and finish with 3... but the 3 is only to see if there are any deep scratches left from the 15.... if the 3 is too fine for you, then go over with 5 to finish. Keep all grades separated in double plastic bags so they don't cross contaminate. If I can find it there is a post on procedure... Bill
See dokasphotos.com , look under "Articles"
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