Tachihara 4x5 question

[Sigurd Wik]

Hi all,

My first post here.

I fell and broke the glass on the back of my Tachihara, luckily (what I believe to be) the fresnel lens is intact. I'm a bit new to this and not quite into the terminologi fresnel lens/ground glass/protective glass. I know that what is closest to the front of my camera is a matte glass (plastic?), and the rough side of this matte piece faces forward. I think this is the fresnel lens. Behind this piece was the glass that is now broken. This is the only two pieces of glass that was at the back of the camera. So does anybody know if the broken glass is just a protective cover glass that I can simply replace with clear glass wothout any concerns for focusing problems? I am not able to shoot a focus test right now, as I have sent the camera back to a local dealer who will take a look at it.

The broken glass was totally shattered, so I don't have it to see if it was clear or matte, as I have been told that this would determine if it was clear glass or a ground glass that is broken. However, I was able to focus on the remaining (fresnel lens?), but I can't shoot a test as the back is sent away.

Don't know if this was explained very well, but I appreciate any inputs.

Sigurd

[Jon Shiu]

The ground glass on a Tachi is a combination piece of plastic that is ground on one side (facing lens) and grooved on the back side, ie Fresnel. The cover glass is to protect it from scratching and has gridlines on it.

Jon

[Alan Gales]

Jon is correct.

Midwest Photo Exchange has an exact replacement with the gridded lines for $35.00.

[Sigurd Wik]

Thanks!

Does this mean that I can use a piece of clear glass to cover the fresnel, and that the thickness of the glass is not that important? Going on a trip in two days, so I don't have time to have new glass ordered from a photografic dealer.

Sigurd

[Ken Lee]

If Midwest Photo doesn't work out for some reason, you can get in touch with the manufacturer (which is still in business) here.

[AJ Edmondson]

Sigurd... the cover glass should just be a clear glass if the Fresnel has a matte side forward and the Fresnel grooves facing the glass.

Joel

[Alan Gales]

Thanks!

Does this mean that I can use a piece of clear glass to cover the fresnel, and that the thickness of the glass is not that important? Going on a trip in two days, so I don't have time to have new glass ordered from a photografic dealer.

Sigurd

If it's close to the same thickness it will work. It has to work with those "thingys" that hold it in place.

Sorry about getting technical there.

[Alan Gales]

Ken might know the real name for those pieces of metal that hold the ground glass in place on view cameras.

Hey Ken, What do you call your "thingys"?

[Sigurd Wik]

Thanks to all for excellent and fast feedback! I like this forum.

Sigurd

[Sigurd Wik]

Got a bit uncertain...

As I haven't got the back here now I can't check, but from what I can remember the groove side faces forward (closest to lens) and the matte side faces backwards. Do I remember wrong, or can this be the case?

The camera is bought new, so I rule out disassembling/replacement issues. Also, I have used it without any problems so far.

Sigurd