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View Full Version : Fresnel For Shen-Hao?



Hagai Kaufman
3-Nov-2001, 03:39
Hi everyone,

I just got a new shen-hao 4x5 camera. very nice machine, although the finish of the metal parts is so-so. Camera is solid and good, as been metioned several tim es here so I don't want to repeat it.

Does someone know if I can fit it with a fresnel screen, and where to get one ?

Thanks,

Tom Perkins
3-Nov-2001, 09:30
The Maxwell screen is marvelous. I got the tip from reading the threads on this forum. You can reach Bill Maxwell at 404 244-0095. He'll be able to help you figure out if it will fit. Good luck.

Ken Burns
3-Nov-2001, 14:43
Hagai:

You can get a Beattie Intenscreen Plus for almost any camera.

David Willis
3-Nov-2001, 15:32
I've been pretty pleased with the Shen Hao without a fresnel, but I've thought of adding one too. I am considering buying a flexible page magnifier from Edmund Scientific and cutting out the middle. Not as nifty as some of the other options, but very cheap and may be quite functional. I plan on testing it before shooting anything important.

Dave

mo
3-Nov-2001, 20:08
I also have a shen -hao camera and i bought a used frenel screen from a local photo shop. It works very well. All you need to do is to put on the outside of the Ground Glass next to where you look at on the glass. My pictures are very sharp. As Dave Willis suggested, you can purchase a fresnel screen from Edmund Scientific. (Buy one that is 1/16 th of an inch thick.) Hope this helps. Mo Kenny

Nghi Hoang
17-May-2005, 14:18
Refering to the post above, why does the fresnel screen have to be 1/16th of an inch thick? What will happen if the thickness isn't as exact? I have a Shen Hao 4x5 also and have been considering a fresnel screen to help with focusing.

Emmanuel BIGLER
17-May-2005, 14:55
The thickness of a Fresnel lens does matter if the Fresnel is put between the lens and the GG. Say : in front of the GG seen from behind the camera.
If it is put over the GG, but after the GG, between the GG and the human eye, its thickness does not matter at all for final image sharpness on film ; but in this 2-nd configuration where no camera and GG re-calibration is necessary, the plastic can be easily scratched. All Fresnel lenses I'm aware of for photographic use are plastic and easily scratch-able. As far as managing the image brightness, both configurations are IMHO, absolutely identical.

3-rd party GG manufactuerers who choose solution#1 i.e Fresnel in front of the GG usually have a trick so that the end user has just to swap the older GG for a brighter one, but be careful and check with the 3-rd party GG manufacturer for proper installation procedures. If you simply add a Fresnel lens in front of the GG you'll induce a focus shift.