Have been trying to figure out how to attach a detachable fresnel lens onto the back of my 8x10 Chamonix and have have yet to figure out a way to do this. Suggestions will be greatly appreciated.
Thanks
Have been trying to figure out how to attach a detachable fresnel lens onto the back of my 8x10 Chamonix and have have yet to figure out a way to do this. Suggestions will be greatly appreciated.
Thanks
Some scheme involving velcro dots or small high energy magnets come to mind... Securing them with some contact cement or hot glue will make the fasteners reversible if you change your mind... These can hold some strips that would support the fresnel...
Or see if the GG clips will extend enough to leave a fresnel on all the time...
Think, think, think...
Steve K
Tried to figure out how to simply adapt my 8x10 rigid fresnel lens to the back of my 8x10 Chamonix and could not figure out a simple reversible way to mount a fresnel. Then I saw up for auction an 8x10 inch fresnel lens described as
"Ultra bright super slim Fresnel lens, only 0.5mm thickness. Size195x248x0.5mm, fits almost all 8x10 camera, like Linhof, Toyo, Sinar...." for $69.99 shipping included. Item location: Hong Kong. Figured it was worth taking a calculated chance and bought the fresnel lens. Took about a week to arrive. The fresnel lens was bagged and triple bubble wrapped.
It arrived and placed it on the back of the Chamonix and seemed like it would work. The long dimension was 0.1mm too long to fit above the ground glass so trimmed off 0.1mm with an Xacto knife - easy since the fresnel is only 0.5mm thick. Three passes with the pointed Xacto knife 's blade and a clean cut. Unscrewed the 4 Philips head screws holding down the 2 metal strips holding in the ground glass. Slid the fresnel under the metal strips and tightened the screws.
Image was a joy to view. Works great with my lenses from 250mm up to 508mm. I seems like it will also amazingly work with my 120mm Nikkor but I first need to fabricate a recessed lens board to be able to get the 120mm to focus at infinity. Focal length of the fresnel was a perfect match. Now with a pair of cheap CU glasses, I can easily view the full image under my dark cloth. Because of the thinness of the fresnel, it does bow out from the ground glass in the center by maybe 0.2mm. This bothered me at first but in practical use it is of no consequence. When I use a loupe to fine focus, it pushes the fresnel in contact with the ground glass.
Will be ordering another same 8x10 fresnel lens and cut it down to fit my Whole Plate camera.
On my Shen-Hao, I used the existing clips to hold it into place in a manner which required no modification at all to the camera.
Greg,
Sounds very interesting. The seller is Rudy, who also makes bellows. He is very responsive, in my experience.
Can you still easily focus on the GG grain using this fresnel?
I checked the listing but did not see any directions. I remember seeing something similar that was allegedly designed for mounting in front of the glass. That concerned me because I thought even though it was so thin it would still throw the focus off, so I never followed up.
This would be nice on my WP camera, and maybe my 5x7.
I can easily focus on the ground glass with the fresnel in place. I have to admit this thin fresnel lens by far outperforms my 8x10" OEM Sinar fresnel on my 8x10 Sinar Norma... but then the 1960s Norma and its 1980s OEM fresnel lens aren't exactly state of the art modern pieces of photographic equipment.Originally Posted by David Karp
As far as mounting the fresnel in front of the GG... technically the fresnel lens would throw the focus off, but because it is so thin and I normally stop down to at least f/45, I doubt that I would ever notice the focusing being so infinitesimally off but it would always bother me that it was that fraction of a mm off. Back in the 1990s, I was using a Nikon Multiphot. Went to clean up the GG and fresnel and when I re-assembled the back put the fresnel on top of the GG. Then for a bit of time my photomicrographs were always just slightly out of focus. Came to find out that the fresnel lens was put in front of the GG and Nikon did account for this change in focus...
Thanks Greg. I guessed that what you say is true, but also would always feel the same way. It is good to hear that the fresnel is so easily installed and removed. I will look into this when my WP camera is up and ready to go! In poking around eBay yesterday, I saw that Rudy also sells this product in 5x7.
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