Shen Hao TZ45 IIB - Ground glass dim

[jamiek]

Just purchased the camera (Shen Hao TZ45 IIB) off someone one on here. It seems an excellent camera.

The only thing that is bugging me is the ground glass. It is really dim so not easy for looking at composition. I have a proper elasticated dark cloth to keep light out when I view the ground glass but still its really dim and impossible to use in low light situations.

Does anyone have any advice one this? I dont really fancy spending ALOT. But any ideas are appreciated. I hear to get a fresnel helps, does anyone know anywhere I can get a fresnel sheet cheap so I can cut it myself instead of paying 65pounds..

Cheers,
Jamie

[Songyun]

I hear to get a fresnel helps, does anyone know anywhere I can get a fresnel sheet cheap so I can cut it myself instead of paying 65pounds..

Cheers,
Jamie

Just in the other post, there are quite a few Chamonix users don't use their fresnel.

[jamiek]

I shall keep my eye out for people selling them then

[Peter K]

Jamie, often a dark gg is only dirty. Remove the gg carefully from the camera. Note all washers, distance pieces, screws etc. Then wash the gg with soap and luke warm water. Dry it carefully without removing the grid, focusing marks etc. Mount the gg and try it again. If it's still too dark, you can try a cheap fresnel-loupe from an optician. This fresnels are thin but work well with cameras up to 4x5".

The focal lenght of the fresnel lens should be nearly the same as the taking lens. E.g. for a 150mm lens choose a 2x-loupe. How to calculate the focal-lenght from the magnification you can find here.

[bobwysiwyg]

I've heard folks mention that such lenses, sheets really, can be found at places like Officemax, Staples, etc. You would have to cut it to fit and I have no clue as to the quality, but suspect it would be an inexpensive test at least.

[Rick Floyd]

Jamiek: I think the obvious question is what lens is on the front? Could the lens be the cause of the dim view?

RF

[jamiek]

The camera is like new so the ground glass should be free of dirt, I'd of hoped so anyway!

I shall call into staples today and have a look around.

Rick, the lens isn't the fastest so that wont help (Fujinon SWD 90mm f/5.6).

[Peter K]

The camera is like new so the ground glass should be free of dirt, I'd of hoped so anyway!

The rough surface of a gg has a very big effective surface with all the little "valleys and mountains". Specially if grinded and not etched, such an isolator like glass holds the dust like glue.

[Clement Apffel]

Washing the ground glass as a start is a good piece of advice.
When I got my Cambo (used), I was more or less with the same problem that you have with your camera. The cleaning did improve the brightness.

Some weeks ago, years after the original purchase, I found myself trying to do a home made ground glass.
Using this tutorial:
http://www.dokasphotos.com/techniques/ground_glass/

I did not have the chance to find 5 microns nor 3 microns grit.
But I was offered a sample of 7 microns grit.

It worked just fine. I ended up with 2 new ground glass for my 2 4x5” cameras.
My ground glass is 1.5 stop brighter than the cambo’s !!! and 0.5 stop brighter than the chamonix’.

The total cost was like 16€ cause I bought some spare glass for being able to quickly ground some other if ever I break one some day.

Before that, I considered Steve Hopf’s ground glasses that are probably the best price/quality ratio for a plain ground glass.

Last point: a Fresnel lens is not necessarily a magic bullet.
A Fresnel on very dim ground glass will end to be a very dim Fresnel. If you see what I mean.
And personally I don’t like Fresnel lenses. I find the lines are disturbing the focusing.
I recently had the opportunity to focus through a Sinar Fresnel and I had the same feeling than with my Chamonix Fresnel eventhough the lines were thinner.

My advice would be to find a cheap clear ground glass either by making one or by purchasing a hopfglass. (around $35 with clipped corners and grid IIRC EDIT : for a "ultra fine")

hope it helps,
regards,
CA

[RichardRitter]

but still its really dim and impossible to use in low light situations.


Cheers,
Jamie

Yes all cameras are hard to focus in low light. I some time will take a flash light and shine it on the main area to do the focusing.