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Wally
2-Jul-2008, 14:34
My newly acquired used Shen Hao arrived :) , but it's ground glass was in backwards, with the etched side facing my eye.

I flipped it around, but the clips don't hold it in position and it rattles.

Do these normally come with a fresnel, or should I just bend the clips a bit to make them hold the GG tightly?


// Wally

Walter Calahan
2-Jul-2008, 15:00
After removing the clips from the camera, don't do this while attached to the camera, gently bend the spring portion of the clips a little bit by hand so they hold the GG tight to the camera.

Some cameras have fresnel lenses, other don't.

Wally
2-Jul-2008, 15:06
Thanks, Walter. Will do.

Anybody with a Shen Hao: Do you have a fresnel in yours?


// Wally

Dave Parker
2-Jul-2008, 15:07
I would bend the clips gently and take a couple of test shots, to ensure your focus plane is correct, you will know if it is not, because the images will be soft, if that is the case, you should be able to get a hold of shen and purchase or gets the dimensions for a fresnel.

Dave

Turner Reich
2-Jul-2008, 20:30
Return it, get one that is correctly assembled. I, like an awful lot of others have one of these and the issue has never come up. Contact the sell right away before you start to modify it.

willwilson
3-Jul-2008, 12:02
If you are swapping out your ground glass I can't say enough about the Bosscreen. I think I have tried all the different focusing screens at one point or another and the Bosscreen won hands down. Its not as bright as some of the fresnels, but it is smooth. This makes it very easy to focus with a loop. I think fresnels tend to be better for taking in the whole ground glass, but they are tough with anything wider than say a 90mm on 4x5.

If you do decide to go with a fresnel make sure you can return it, if you are not satisfied. A focusing screen is a very personal piece of gear and everybody has their own favorite.

I've never had a problem with the wax melting or bubbling, and I have had it in 105+ degree heat in Death Valley, but you never know. I carry a back-up always.

As a side note, the Shen Hao is a great camera, I use one myself. Great gear for the money. I would suggest that you test the ground glass alignment. Mine was out of wack a bit and need shimming. There was a great detailed article in Viewcamera about it.

-=Will

Wally
3-Jul-2008, 16:29
Thanks for the suggestion on Boss.

I have a depth micrometer, which reads about 0.187" measuring from the camera mating surface to the frosty surface of the GG. I'm going to take a shot at a 12 in. ruler 10 feet away that's at about a 30 degree angle from the plane of sharp focus, focus on the 6, process it and see where the focus is actually at.

As I understand it, optics gets involved when adding a fresnel - it's not simply a matter of keeping the ground glass at the same place. Does the focusing point move forward when a fresnel is used, and thus would require that I shim the back of the groundglass, or does it move back? And what would I do then??

Turner Reich
3-Jul-2008, 16:47
I have a depth micrometer, which reads about 0.187" measuring from the camera mating surface to the frosty surface of the GG. I'm going to take a shot at a 12 in. ruler 10 feet away that's at about a 30 degree angle from the plane of sharp focus, focus on the 6, process it and see where the focus is actually at.

As I understand it, optics gets involved when adding a Fresnel - it's not simply a matter of keeping the ground glass at the same place. Does the focusing point move forward when a Fresnel is used, and thus would require that I shim the back of the ground glass, or does it move back? And what would I do then??

The depth is correct but I have to congratulate you on testing the focus, I had a medium format camera that had a focus screen, which was adjustable, out of focus for a long time until I learned that they came from the manufacture within a tolerance. Within specs is not what I would call right on.

Bobf
3-Jul-2008, 17:17
<snip>
As I understand it, optics gets involved when adding a fresnel - it's not simply a matter of keeping the ground glass at the same place. Does the focusing point move forward when a fresnel is used, and thus would require that I shim the back of the groundglass, or does it move back? And what would I do then??If you place the Fresnel between the ground glass and your eye (i.e. your side of the gg) you do not need to do anything. That's the simplest solution and what I did with my Shen.

Bob.

Erik Larsen
3-Jul-2008, 17:34
Wally, I picked up a shen hao branded fresnel from Badger and it came with a clear gridded piece of glass to protect the fresnel, not intended to be used with a ground glass was my impression. I haven't done a focus check because I haven't noticed my shots being out of focus except for when I make stupid errors.
regards
Erik

willwilson
3-Jul-2008, 20:31
Checking the focus of your camera is essential. It's often not noticeable in normal shooting circumstances, but then you get in a situation where you are only stopping down to f11-f16 and some movements are involved. Also, macro tends to be very sensitive to alignment issues.

My seat of the pants can't fly that much, so I always check the alignment of my camera just for the peace of mind. Good shooting...-=Will

Wally
4-Jul-2008, 19:17
The depth is correct but I have to congratulate you on testing the focus, I had a medium format camera that had a focus screen, which was adjustable, out of focus for a long time until I learned that they came from the manufacture within a tolerance. Within specs is not what I would call right on.
I read how to do it by scouring the forum's archives. I love this forum!

Wally
4-Jul-2008, 19:18
If you place the Fresnel between the ground glass and your eye (i.e. your side of the gg) you do not need to do anything. That's the simplest solution and what I did with my Shen.
With the 'edgy' side of the fresnel facing out, right?

Bobf
5-Jul-2008, 08:56
With the 'edgy' side of the fresnel facing out, right?With the smooth side of the Fresnel facing out so you can put your loupe on the smooth side and not damage the lens ridges. Not sure if it makes any difference optically but it's certainly more practical that way.

Mike Snider
5-Jul-2008, 10:33
I own a Shen Hao and installed a fresnel from Badger Graphics. It currently sells for about $80.00. It comes in two pieces; a ground glass/fresnel comob and a cover piece with grid lines. The ground glass goes in first with the ground glass side facing the lens and the side with the fresnel facing towards the back of the camera. The cover piece goes on top of that. It works great!

Mike Snider

Wally
5-Jul-2008, 11:11
With the smooth side of the Fresnel facing out so you can put your loupe on the smooth side and not damage the lens ridges. Not sure if it makes any difference optically but it's certainly more practical that way.
I hadn't considered the fact that these things are plastic and can get munged by my loupe!

As long as it doesn't move the optical plane with respect to the mechanical plane, I guess it makes no difference. Thanks.