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Jehu
6-Apr-2009, 16:29
I'm having trouble with my compositions because I just can't see them that well in the glass. Are there different qualities available? Or do I just need to develop my skills?

My camera is a Calumet monorail.

aphexafx
6-Apr-2009, 16:45
There is better quality ground glass than most OEM ground glass, except that very high end cameras probably come with good ground glass to start with. My Mamiya did. My Cambo 4x5 did not.

So, as a result, I am just about to purchase a custom 4x5 piece from Steve Hopf on eBay. His product is hand ground and he has a very fine version that he will cut to your specs, corner, grid, etc., all for around $20 for 4x5.

There are other (very much) more expensive products with wax, etc. that cost many times this price, so it is probably worth betting on Hopf’s. If you still want one of the fancier types after trying Hopf's, well then you have a backup.

Hope that helps.

aphexafx
6-Apr-2009, 16:48
Also note that focus lengths less than ~120mm will start to affect the image on your ground glass as the light is less and less parallel the wider you go. This causes you to need to move your head around to catch the image as you move away from the center. If this is what's happening, you would benefit from a Fresnel lens.

David Karp
6-Apr-2009, 17:43
Steve Hopf makes a nice ground glass. I have one on a 5x7 reduction back.

However, other options can provide a brighter image than a standard groundglass. Cambo makes a Fresnel lens that sits on the viewer's side of the groundglass. This will brighten the image, but some people feel that the fresnel (any fresnel) makes it a bit harder to focus due to the lines from the fresnel lens.

Other cameras require that the Fresnel be on the film side of the GG. If installed properly, all will be fine. If not, the plane of focus may not be in the proper place. You need to make sure that everything is installed properly for the type of camera you are using. If you are using a Calumet that is actually a Cambo camera, no problem, as mentioned above, because the Fresnel goes on the photographer side of the GG.

Calumet also sold what they call a Super Sharp Screen (and maybe they have some left). These are actually a product called a Bosscreen. These are camera-specific, so a non-Cambo Bosscreen may not be right for your camera, even if it fits physically. These screens have their own issues, but the image is nice and even, and snaps into focus very well. Search this forum for "Bosscreen" for many comments and discussions

Maxwell also makes what is said to be an outstanding Fresnel, without many of the issues that trouble some regarding Fresnel lenses. These are expensive and pretty much custom made. Search this site for "Maxwell."

Hope this helps.

lxdesign
16-Apr-2009, 10:19
Thanks for this info guys, I need to replace the ground glass in my camera.

Jehu
16-Apr-2009, 10:31
I just got my new glass from Steve Hopf yesterday. I set up in my front yard just to get a look at it. It seems like a worth-while improvement so far. I'll be out shooting in the next couple of days. I'll post up after I've had a chance to put it to the test.