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buggz
29-Feb-2012, 20:13
Posting this in a separate thread, so the original thread would be not contaminated with my newbie confusions.
And perhaps, it will hopefully help someone else.

Oh wow!
I actually found out what you were talking about!
Heh, sorry but this just does not seem very obvious as springing out the back.
At least not to me.
First I removed the GG frame portion, and fitted a holder.

BTW, I have the entire back of mine oriented in portrait orientation, so it, the GG frame portion, slides upwards.
Heh, I actually, "discovered" the landscape/portrait orientation playing w/ the camera previously.

So now, I have the GG frame portion removed, and amazingly, a holder fits perfectly.
Cool, it fits, but what holds it in place?
Ahh, look, what do these sliding tabs do? Woo, it clips into the holder, holding it!
Duh, I feel soo stoopid...
Thanks for the info!

Another stoopid question:
With the GG frame portion off, it's what is called a Graflock back?



I use a PA-45 in my Sinar F2 all the time with no issue. You push in the two chrome spring clips above and below the ground glass and slide the ground-glass frame sideways. It comes unclipped and will come off the camera in your hand. Then, place the PA-45 in its place, making sure the ridge to the right of the opening seats in the slot on the camera, the same way any film holder would do. Then, slide the two tabs at the top and bottom of the back so that they slide into slots at the edges of the PA-45 and lock it in place.

The Graflok design includes the ground-glass frame held on with spring clips, and the two tabs to lock into those slots. The "standard" only requires that the tabs be positioned in a particular way.

Note that the Graflok tabs must be open for the ground glass frame to seat properly.

Rick "it's only confusing the first time" Denney


Hmm, I just bought a Fuji PA-45 back.
I have some FP100C45 film on the way.
I have test mounted this back in front of the ground glass, by opening/extending the back by use of the two levers, one on each side.
I am assuming this is how you would mount 4x5 double sided sheet film holders as well.
Is this incorrect?
I'm confused about the Graflock part above, and attaching this in lieu of the GG ?
I am working from "instructions" found here:
<<http://www.webster.edu/acadaffairs/asp/mediacenter/Photo/equipment%20manuals/sinar_introduction_manual.pdf>>
I will take some pics tonight.


Yeap, sure is confusing.
I have taken the back completely off, and apart.
Though, I have not tried to take the GG off while the back is still on.
I will look at this tonight.
Any problems with the method of putting the film holders in front of the ground glass?


For holders that don't have protrusions that will bear on the glass directly, and if the spring arrangement of the ground-glass holder has sufficient travel to accommodate the thickness of the back, then there's nothing wrong with just sliding it under the ground glass. I do not know whether the back on the Sinar will accommodate a Polaroid 405, aside from the issue described by the OP. It will absolutely accommodate a Fuji PA-45 in that way, though not with an abundance of margin. I just tested it. The PA-45 back is about 1.07" thick.

Rick "noting that the bail tab has a 1" travel, so lifting the back itself is required with the PA-45" Denney

rdenney
1-Mar-2012, 07:14
With the GG frame portion off, it's what is called a Graflock back?

Graflex developed the Graflok interface to make it possible to attach roll-film backs to Graflex cameras. They first came out in 1949. I do not believe that Graflex patented the Graflok, but they certainly trademarked the name. At about the same time, Carl Hans Koch designed the first Sinar camera (which came out in 1948), and as far as I can tell it included an "international" back. That back is functionally identical to the Graflex Graflok. The ground-glass frame from a Sinar Norma fits in a Graflok-equipped Speed Graphic (after removing a couple of accessory tabs), and even the clip-in accessories for the ground glass are interchangeable. One can put a Graflex folding hood on a Norma, and an early Sinar Fresnel frame on a Graphic. I cannot tell from an Internet search which came first, but clearly somebody was making sure that their camera accommodated the interface used by the other. Given Sinar's relative insignificance in the market at the time, probably Sinar went to school on Graflex, but the dates are what they are: The first Sinar appeared in 1948 and the Graflok first appeared in 1949. Maybe the very first Sinars didn't yet have the International back. Maybe the standard governing the International back had been discussed and circulated within the industry well enough so that both could work independently. It would not be the first time Graflex applied a "Graf-something" trademark to a feature incorporating an international standard.

People commonly use "Graflok" (though often misspelled) to describe an international back. Functionally, they are interchangeable.

There are guys here who know far more Graflex history than I do and may know more historical details.

I have never seen any official description of either Graflok or the standard defining the international back, so I'm reverse-engineering what I think constitutes a Graflok back: The removability of the ground glass, the width between the rails above and below the frame, and the location, depth of insertion, and other dimensions associated with the locking tabs. The clips that retain the ground glass frame are apparently not standardized in the international standard--ground glass frames from one camera with an International Back may or may not fit in another camera with such (the near-compatibility of the Norma and Graphics notwithstanding). The size of the space into which the accessories fit once the ground glass is removed is mostly dictated by the size of a standard sheet film holder. That is a separate standard that dates from very early on, and that standard dictates the size of the holder, the location of the locking ridge that is used for alignment, and so on.

All my various holders that are designed to fit International/Graflok backs work equally well into the Graflok back of my Speed Graphic and the International back of my Cambo and Sinar cameras. That includes original Graflex roll-film holders, a Wista 6x9 holder, a Sinar Vario roll-film holder (though it can also be slipped under the ground glass), a Shen-Hao 6x12 holder, and a Fuji PA-45.

Rick "could Graflex have 'channeled' the work of some obscure Swiss photographer/designer?" Denney

Robert Crigan
3-Mar-2012, 04:19
I think you may have misunderstood the way film holders are inserted into the camera. The back with its ground glass is not meant to be removed. Those tabs you mention are for holding in place a roll film back or other sort of back.
ShHeet film holders should be slid under the ground glass back from one side. The springs of the back allow it to make room for the holder and to hold it in place.
It's a bit hard to learn how to use large format cameras without having someone to learn from, even if it's just to watch them work once.
Good luck
Robert, Melbourne


Posting this in a separate thread, so the original thread would be not contaminated with my newbie confusions.
And perhaps, it will hopefully help someone else.

Oh wow!
I actually found out what you were talking about!
Heh, sorry but this just does not seem very obvious as springing out the back.
At least not to me.
First I removed the GG frame portion, and fitted a holder.

BTW, I have the entire back of mine oriented in portrait orientation, so it, the GG frame portion, slides upwards.
Heh, I actually, "discovered" the landscape/portrait orientation playing w/ the camera previously.

So now, I have the GG frame portion removed, and amazingly, a holder fits perfectly.
Cool, it fits, but what holds it in place?
Ahh, look, what do these sliding tabs do? Woo, it clips into the holder, holding it!
Duh, I feel soo stoopid...
Thanks for the info!

Another stoopid question:
With the GG frame portion off, it's what is called a Graflock back?