ground glass thickness

[Whiteymorange]

A question from an ignorant man: many of the old LF cameras that I have inherited seem to have the frosted side of the GG facing out - on the back side of the camera, not facing the lens. They are old and have been kicked around some, so I can't say that that is the way that they were made, but they seem to work pretty well with modern film holders. Is it possible that the previous owners reversed the glass to make up for the difference between glass plates and film in terms of the placement of the emulsion in relation to the lens?

Thanks,
Whitey

[smieglitz]

..the glass must be positioned so that the inner (frosted) surface of the glass is the same distance from the camera back as the film will be. In 4x5s, that's 0.195" or 5 mm (if I remember correctly)...

Here's a page that lists the critical "t" distance you refer to as well as other dimensions for 4x5 and all common sheet film holders:

http://home.earthlink.net/~eahoo/filmhold.html

[Murray@uptowngallery]

Is that Whitey Morange or Whitey M. Orange?...just curious so I don't mispronounce it in my head every tiem I see it.

My first thought was the gg was reversed by someone, and you have an interesting reason why. Hopefully someone knows how plate vs film applies to your proposed explanation.

I just borrowed a Zone VI camera from a guy at work to study and noted he had put his GG in backwards from the first time I looked at it.

Other than in my CG that has an Ektalite Fresnel, I do the ground side toward lens/Fresnel behind GG method for my experimental stuff (which I have only looked thru but never shot film with yet...I'm easily amused by the ground glass image for now).

I am spatially challenged. What confuses me is whether to take film thickness into consideration or not when building a camera back, and if so, whether to make the spacing deeper so the surface of the film is at 0.197" for 4x5. I realize film thickness is within the tolerance, filmholders might be warped, etc, so in the interest of being neurotic, and having to go to the effort of spacing anyway, why not go for dead center ? Maybe paper negs are thicker than 0.007" too.

Thanks

[Whiteymorange]

It's Morange, though I often tell people to spell it the other way so that they get it first time, you know, orange, with an M in front of it. Funny thing is that the reaction I get when I say this varies by region (my wife does the same spelling thing and gets the same reaction.) In eastern MA, most people seem to get it. In other locations where we have spent some time we more often get "huh?" Must be an NE thing.

The cameras that I have with the glass frosted in the back seem to work great. Being of the sometimes hamfisted variety of man, I'm going to leave them that way. If it ain't broke...etc.

And Murray, what about that negative feedback??

[Murray@uptowngallery]

The neg FB...I must wear it like a Badge of Courage, milk it for all it's worth, get my mileage out of it, etc.

I am cooling off a little....so I hesitate to broadcast the name of the seller in bold letters, as they have initiated a Square Trade resolution. I got the (-), my first ever I might add, as retaliation for GIVING neg to a seller who sent me a worn, beat product with a 1988 date code, described as new then offered to exchange it. Another winning bidder on same product got one in similar condition dated 1983, and was equally unhappy.

I put a link to pics on the web in my feedback since it appeared to be blatant fraud, not an oversight (two people in a row, come on!). Offer to exchange it I didn't respond to because they rationalized it in many ways.

I will wait until the Square Trade thing pans out & see if the resolution was an honest fix or ...something else. If it's corrected properly, I'll undo my smear campaign. IF invoking Square Trade ends up being part of a darker plot by the seller, no reason to assume so yet, I will be out with a virtual flame thrower, to protect innocent unsuspecting fellow photographers from such indignity. I think it's too much work for most people who get burned, but I may have given them a wake-up call (only a one-alarm so far).

I will take my chances with the average eBay clown who 'doesn't know anything about cameras' and not be surprised if an item doesn't meet description or has functional issues, but a dealer with a condition rating system posted on their website?...uh, uh, no way.