In search of help on adding a Fresnel lens to a Burke and James 8x10 focusing screen

[chazum0]

Hi All

I recently acquired an old Burke and James all metal 8x10 studio camera that I'm preparing to begin shooting with. Unfortunately, the ground glass back has no Fresnel lens and it's incredibly difficult (and annoying) to compose with in my studio where I will primarily be using the camera. So far I've done a little bit of preliminary research about the pros and cons of which side the mount the Fresnel lens on, but I'm still uncertain of what's my best option.

Any suggestions on a good Fresnel lens and a method of attachment would be greatly appreciated.

 

[shutterfinger]

Not knowing how familiar you are with cameras of this size so the clipped corners of the ground glass are to let air out of the bellows as the camera is closed and by looking at the aperture through the clipped corner you can determine if the selected aperture will vignette or not. If you can see the aperture edges it will not vignette. This is true if the lens covers the format.
I had a Sinar that used a fresnel on the back side of the ground glass. It was as easy to focus as a Graphic with the fresnel in front of the ground glass.
Get one of these and experiment before committing to a more expensive photo dedicated fresnel. https://www.officedepot.com/a/products/671085/Sparco-Handheld-Fresnel-Lens-Magnifier/
Cut it to fit the gg opening with clipped corners. The ribbed side goes against the gg.

 

[awty]

Interesting to put them on the back, would be heaps easier.
Is their any modern types that have a good compromise on brightness to sharpness? I find them hard for critical sharpness on the old ones I have. I usually just turn up the lights to focus.

 

[Ian Grant]

A Fresnel is a lens so causes focus shift if placed on the inner side of the GG screen, this is why any removeable fresnel is placed on the rear (outside) of the GG screen.

Ian

 

[AgX]

The question of a good fresnel is hard to answer, as such lens must be chosen with the actual optical situation in mind. That is simply said the distance of both the rear element of the lens and of your eye from the screen.

 

[juan]

I once did what shutterfinger suggested. It did help.

 

[ic-racer]

I put one of those inexpensive reading fresnel lenses on my Shen Hao just as a test. I quickly cut some notches in it to slide under the tabs that hold the ground glass in place to hold the fresnel in place while I tested it. That was ten years ago, looks like it is still in place. If anything it serves as a ground glass protector while transporting the camera.

 

[Ian Grant]

I put one of those inexpensive reading fresnel lenses on my Shen Hao just as a test. I quickly cut some notches in it to slide under the tabs that hold the ground glass in place to hold the fresnel in place while I tested it. That was ten years ago, looks like it is still in place. If anything it serves as a ground glass protector while transporting the camera.
View attachment 267816

That's the correct approach, I have two of those fresnels, but then my 10x8 Agfa Ansco Commercial View came with a NIB Beattie Intenscreen thrown in for free, and the camera & Dagor, well complete kit was inexpensive

On the Cambo (Calumet) Cadet I owned for a few years and used over only over one long weekend there was a very thin but excellent fresnel, it lay flat and gave a good bright image. I've been looking for similar since with no luck. I have found some that I can cut down for 5x4 but theey don't lie flat, and they are too reflective.

Ian

 

[ic-racer]

I have been thinking about one of those all-in-one combined fresnel and focus screen. But when I look at my fresnel, I see a lot of marks from my backpack. It really has been protecting my ground glass. So, if I got the all-in-one, then I'd need a piece of glass behind it to protect the $150 plastic focus screen. Then I'd need something to keep the glass from breaking....

Another option to protect a valuable plastic all-in-one focus screen is a "U" shaped piece of plexiglass that slides around the focus screen. In fact, that wood channel in the picture above is to catch the lip of the 'ground glass protector' when in place (though I don't have one).

 

[cowanw]

If you do lay a fresnal behind your GG and use the clips that hold the GG in, you may need to source slightly longer screws of the same diameter.

 

[chazum0]

Not knowing how familiar you are with cameras of this size so the clipped corners of the ground glass are to let air out of the bellows as the camera is closed and by looking at the aperture through the clipped corner you can determine if the selected aperture will vignette or not. If you can see the aperture edges it will not vignette. This is true if the lens covers the format.
I had a Sinar that used a fresnel on the back side of the ground glass. It was as easy to focus as a Graphic with the fresnel in front of the ground glass.
Get one of these and experiment before committing to a more expensive photo dedicated fresnel. https://www.officedepot.com/a/products/671085/Sparco-Handheld-Fresnel-Lens-Magnifier/
Cut it to fit the gg opening with clipped corners. The ribbed side goes against the gg.

This is a great suggestion, shutterfinger. I'm going to give the cheap fresnel a try first.

 

[chazum0]

If you do lay a fresnal behind your GG and use the clips that hold the GG in, you may need to source slightly longer screws of the same diameter.

That's a good point. I'll see how much I can back the screws out without them coming off.