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axs810
19-Mar-2015, 19:18
I just bought a Speed Graphic (Pacemaker?) on ebay and was wondering about a replacement ground glass because when the camera arrived it didn't have a ground glass but had a really scratchy fresnel installed. Right now the fresnel doesn't function as anything because the ground glass is missing so it has some wiggle room. I was wondering if this is the kind of Speed Graphic where I can just drop in a new ground glass or if I'm going to need to shim before placing a new ground glass in.


My cameras serial number is 902386.


I just placed an order with Steve Hopf for a new ground glass. I'm really hoping I can just drop the new ground glass in without shimming, but if that problem does arise what would be the best way to shim the ground glass for best accuracy when focusing?
Jon Shiu
19-Mar-2015, 21:24
Put the Fresnel in first. Then put the ground glass on top.

Jon
axs810
19-Mar-2015, 21:27
Only problem is that the fresnel takes up a lot of space. Right now it's on my camera and there's only like a few mm of wiggle room. Feels like almost 2-3sheets of printer paper can fill the gap so I don't know how well the ground glass and fresnel will fit together under the clips.
Jon Shiu
19-Mar-2015, 21:53
Normally, the Fresnel sits in kind of a "well", with deeper edges. If you haven't already, take the door off, it unclips. Then take the clips off and see what the situation is.

Jon
RichSBV
19-Mar-2015, 22:41
The GG clips are spring clips that hold pressure on the GG, There will seem to be less room without the GG in place, but make sure your new GG isn't too thick! And make sure the fresnel's grooves are facing you, not the lens. Of course the frosted side of the GG then faces the fresnel...

Oh, and your serial number is from a batch of 3000 dated 12/1/1954...
Old-N-Feeble
20-Mar-2015, 08:48
Sorry to intervene but...

Rich, are you sure about the Fresnel orientation?
Dan Fromm
20-Mar-2015, 09:28
Rich is right.

About whether to put the fresnel in front of the GG, it depends on the focusing panel. Pacemaker Graphics have two types of focusing panels, for use with and for use without a fresnel. Graflex Inc. being Graflex Inc., both types have the same casting number.

The GG (or GG + fresnel sandwich) sits on bosses (four, I think, it's been a while since I took one of my focusing panels apart). Focusing panels for use without a fresnel have high bosses, focusing panels for use with a fresnel have the bosses milled down. High bosses ==> put the fresnel behind the GG with the grooves facing the GG. Low bosses ==> put the fresnel in front of the GG with the bosses facing the GG.

Note that all this assumes the fresnel is Graflex' original issue. Not all fresnels are the same thickness.
BrianShaw
20-Mar-2015, 09:42
Dan is right.
RichSBV
20-Mar-2015, 10:09
Dan and Rich are both right :p
Old-N-Feeble
20-Mar-2015, 11:00
I should have been more specific. I should have asked, "Should the Fresnel grooves face the back of the camera?"
BrianShaw
20-Mar-2015, 11:18
Dan and Rich are both right :p

Yes, indeed. In my reply you inherited rightness via Dan's rightness. :)
RichSBV
20-Mar-2015, 11:24
I should have been more specific. I should have asked, "Should the Fresnel grooves face the back of the camera?"

Yes...

Fresnel grooves face back of camera, frosted GG surface faces Fresnel.
RichSBV
20-Mar-2015, 11:25
Yes, indeed. In my reply you inherited rightness via Dan's rightness. :)

Well, I certainly wouldn't mind inheriting from either of you! ;)
axs810
20-Mar-2015, 17:23
131137

131138

131139


Still can't tell...is my speed graphic the kind where I can just drop in a new ground glass or do I need to have the fresnel in front of the ground glass?
axs810
20-Mar-2015, 17:24
131140

131141

131142



Still can't tell...is my speed graphic the kind where I can just drop in a new ground glass or do I need to have the fresnel in front of the ground glass?
RichSBV
21-Mar-2015, 00:04
It's a very slightly different design than the panel I have on hand, but from what I see it should be made for both the Fresnel and GG. If it was made for no Fresnel, there would be some kind of raised sections to make up for the space.

I also took a quick measurement of the thickness of my GG. Of course I now forget. I think it was .062 or so...
axs810
21-Mar-2015, 00:09
.062 mm ???


I just ordered a Steve Hopf ground glass as a replacement :( ...so this most likely won't work with my set up huh?



edit/ In post #15, second photo, is that a raised section?
Dan Fromm
21-Mar-2015, 05:16
What matters for a ground glass is where the front (frosted) side is, not how thick it is.
IanG
21-Mar-2015, 05:49
.062 mm ???


I just ordered a Steve Hopf ground glass as a replacement :( ...so this most likely won't work with my set up huh?



edit/ In post #15, second photo, is that a raised section?


2mm Ground glass is best, older screens may be 1.5mm but it's far more prone to breakage, I make both but only use 1.5mm where 2mm won't fit.

Ian
Michael Cienfuegos
21-Mar-2015, 11:12
It appears that you guys are making a big hoot over nothing. Put the ground glass in as it should be put in. Frosted side to the front. Stick in a film holder and take a photograph as you normally would. If it is out of focus you will know there is a problem. Follow Ian's instructions, Fresnel in first, then the GG. That is how it is an all three of my Speedies.



m
axs810
21-Mar-2015, 11:35
If i do have to use both the fresnel and ground glass I don't think they are both going to fit. I'm not even sure the fresnel I have is original...if that happens what are my options?
IanG
21-Mar-2015, 12:34
If the frame's designed for a fresnel & GG the glass will be loose on it's own, if the frame is only for a GG the retaining clips won't sit flat where they are screwed to the frame and the hood won't lock in place securely.

I have all the permutations of Pacemaker backs, with & without Fresnel, Spring & Graflok. If you add a Fresnel to the rear of a focus frame made for just a GG you need to shim the retaining clips, only other time you need to shim is when you remove a fresnel from a back designed to use one,

Ian
RichSBV
21-Mar-2015, 22:53
You're over stressing where no stress should be! Yes I meant .062 inches, which is close enough to 1.5mm. I think the frosting alone would be thicker than .062mm :D

Your Fresnel looks original to me but it's hard to tell in pics. I couldn't see any raised sections either.

Just wait for your G and see how things fit. But remember that the spring clips do put some minor pressure on the GG. If the Fresnel really wasn't meant to be there, you'll know it.

Here's some more measurements for you. My Fresnel also measures .062. That obviously means if the standard GG was 1.5mm (.062") then your clips would be tight against just that! So we can guess already that your panel was indeed made for both.

And to really confuse you, the measurement on the other side of the panel from the flat section to the Fresnel is .140". Why? To show you hat you don't have a raised section for no Fresnel. The best place to make this measurement is the corner opposite where the film holder would be pushed in as there's a good flat section on the corner of the panel which sits directly against the camera back.

So no worries. Just get your GG, install carefully and enjoy!

Disclaimer: My measurements are "close enough" as perfect is very difficult without much more care and dis-assembly A difference of .001 in this instance wouldn't matter...

And my measurements are in inches at the moments mostly because all dimensions of Graphics are in inches, and my digital caliper needs batteries :p
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