Chamonix Ground Glass

[Andrew Moxom]

Okay, I've owned my Chamonix 451N for about two months now and my only gripe with it is the ground glass screen in that it's rather dim compared to my Canham. In every other espect, the Chamonix is a dream to use. I am thinking about getting a brighter fresnel (with the corners cut on it unlike the standard issue Chamonix one!!) and a new ground glass. I need some help here as I want to try this vendor for the fresnel:- http://lensn2shutter.com/fresnels.html

and this guy for the ground glass:- http://stores.ebay.com/Brilliant-Ground-Glass I got this from another thread already opened on GG specifically.

My question is ( and it maybe deemed a stupid question), do I need both a GG and fresnel, or if I just order the fresnel, would a regular sheet of grid marked glass on top work ie existing grid screen? It appears that the Chamonix viewing screen is just a sheet of glass, not ground. Am I incorrect?

Thanks

 

[Barry S]

Like any view camera, the Chamonix has a ground glass--so you need both. Many of us cut the corners on the Cham fresnel, but you could always test the Cham glass with the Canham fresnel and the Cham fresnel with the Canham glass to see if one or both need replacing.

 

[argus]

Andrew,

Adding a fresnel lens will brighten up any classic ground glass.
If the Chamonix is not factory equipped with a fresnel, make sure you add it at the viewing side of the groundglass, i.e. on the outside of the camera.

G

 

[TheFlyingCamera]

Also consider if your Canham GG/Fresnel set fits the Chamonix, just ordering another set of the Canhams and using that. They're fairly inexpensive. I did that with my Shen Hao, which also came with a rather crappy, dim GG. Made a world of difference.

 

[Andrew Moxom]

When I looked last night, I noticed the Chamonix fresnel has a small rebate about 1/16th" wide machined into the top and bottom edge of the inside facing side of the fresnel. It's a miniscule amount, but it's there. Measuring that rebate depth will need fine tools to get right, and then applying that to a replacement will be quite tricky. I am thinking that replacing the GG as the first thing is likely the best course for now.

 

[freygr]

Just remember to measure the thickness of the glass as it sounds that the Ground Glass and the thickness of the Fresnel lens lip regulates the surface placement of the GG.

 

[Andrew Moxom]

If I just replace the GG, wouldn't that just be a drop in fit? As the fresnel facing side will still be in the same reference point? The fresnel will not be changed and the GG can fit right on top of it.

 

[freygr]

If I just replace the GG, wouldn't that just be a drop in fit? As the fresnel facing side will still be in the same reference point? The fresnel will not be changed and the GG can fit right on top of it.

If the ground glass is the same thickness there will not be any problems. But if the indexing for the film plain is not indexed by the face of the ground glass, and the replacement ground glass is not the same thickness, then you will have a focusing problem. It will look in focus but the ground glass is not in the same place as the film :confused: