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luisefigenio
20-Jun-2014, 14:35
Hi, I did bought an used Speed Graphic. I do have shoot with nikkor150mm , and I'm struggling with the focus. I do focus in ground glass, my target seams perfect in focus, but in negative it is always focus behind the target. In exemple, I did focus on caravan, and in the boy with the gun? What is wrong? could it be problem in ground glass? any help?
117119117120

brucetaylor
20-Jun-2014, 14:46
I suspect the groundglass is not on the same plane as the film holder. I am not an expert, but there were different Graflex groundglass holders, one set up for a fresnel lens before the focussing surface of the glass, and one not. If a plain gg is in place of the fresnel/gg combination the plane of focus will be off. I have also seen gg installed backwards. You may be able to adjust this yourself with care. I'm sure there are some Speed Graphic experts that will comment, or go over to www.graflex.org and you should be able to find answers there.

Jim C.
20-Jun-2014, 15:21
I've received cameras that have the gg reversed for whatever reasons the previous owners thought was a good idea.
I'd check the ground glass, the matte side should be facing inside the camera.

Tracy Storer
20-Jun-2014, 15:25
Jim C. has already posted what would have been my first suggestion. Make sure the ground glass is installed properly, frosted side towards the inside of the camera (and lens) and the plain, glossy side facing out towards you.

Chauncey Walden
20-Jun-2014, 15:32
Do you use a loupe?

jbenedict
20-Jun-2014, 18:21
Do what is suggested above. Take the lens and board off and look to see if the ground glass is frosted on the inside and the part that you look at through the focus hood is shiny.

If that checks out, make a test:

1. Take the lens off the lens board. lock the focus rail at any convenient position. (The lock is the small lever on the right hand side of the focus rail near the icus knob on the right hand side.) Measure the distance from the edge of the lens hole to the ground glass.

2. Put a film holder without the dark slide in the camera back. The holder should have a piece of film in it. Measure the distance from the edge of the lens hole to the ground glass.

3. The distance should be the same for both cases.

Not sure how something could have gotten messed up because I haven't seen everything.

If both distances are the same, ask yourself if, after you focused on the ground glass and closed the shutter to make the exposure, had you locked down the focus rail first? The lock is on the right hand side of the focus rail right by the focus knob. If it wasn't locked, you could have moved the focus rail when you touched the front standard to set the shooting aperture and close the shutter.

You are going to need a loupe of some sort to accurately check the focus. Set up and carefully focus making sure that everything is locked down when you are happy with the focus. After you lock down the focus rail, check the focus before you adjust the aperture and shutter. Insert the holder and expose a piece of film. Take care that you don't bump or move anything when you insert the holder. After you make the shot, open the shutter and aperture and check the focus again. Process the piece of film and see if it is in focus. You don't necessarily have to proof it if you have a loupe to examine it.

If it still is out of focus, I'm not sure what to do next. Throw it in the bay and go have a beer. That will fix anything. ;)

Jeff

Jim Jones
21-Jun-2014, 05:52
This problem has been discussed often here and elsewhere. Look here: http://graflex.org/articles/sanz-cervera/.

IanG
21-Jun-2014, 07:37
The castings used for Pacemaker backs are machined either for a plain screen or a screen and Ektalite fresnel, if it's the second focus frame and the fresnel is missing the register will be out as you describe. The two focus frames look virtually the same and have the same casting number, side by side you can see a difference between them.

I have Pacemakers with plain screens and one with the original Ektalite fresnel, plus I have some Pacemaker backs on format conversion backs so have become quite familiar with the issues. Often the come incorrectly, maybe the fresnels been removed.

Ian

tom thomas
21-Jun-2014, 14:35
Hi, I did bought an used Speed Graphic. I do have shoot with nikkor150mm , and I'm struggling with the focus. I do focus in ground glass, my target seams perfect in focus, but in negative it is always focus behind the target. In exemple, I did focus on caravan, and in the boy with the gun? What is wrong? could it be problem in ground glass? any help?
117119117120

What is the serial number of your Speed Graphic. Knowing then it was made could help determine if it should have a Fresnel installed or not. I've found mention of those with Fresnel in Graflex Service manuals, ie parts lists and even discussion. Plus you don't appear to be using a Graflex original lens, ie the Nikkor 150mm. Could that be affecting the focal distance? Others would know more about that effect.

I dont' see what the problem is with your photo of the young shooter. I see that his face and side of head is in focus but the gun stock is out of focus. I like the effect you've attained there for a portrait. What was the aperture setting? Wouldn't that affect the focal depth of field too.

Brian C. Miller
21-Jun-2014, 14:59
Hi, I did bought an used Speed Graphic. I do have shoot with nikkor150mm , and I'm struggling with the focus. I do focus in ground glass, my target seams perfect in focus, but in negative it is always focus behind the target. In exemple, I did focus on caravan, and in the boy with the gun? What is wrong? could it be problem in ground glass? any help?

The lens is not the culprit here.

Your problem is exactly the same problem I had when I bought my Super Graphic. The GG/Fresnel had been swapped for a plain GG. If your Speed Graphic's GG has the ground side facing the lens, then you need to buy a replacement GG/Fresnel combination. A book magnifier Fresnel lens will not work because the Fresnel plastic for cameras is much thicker.

If you do need to buy a ground glass/Fresnel replacement, your work will not be done yet. The replacement will still not be in the same plane as the original, and you will need to do some testing and put in shims to get the glass into the right spot. (If you are not the kind of person who builds and modifies things, now is the time to find someone who does that.) To tell if you have your camera's glass in the right spot, extend the bellows all the way, and put a ruler in front of the lens. Move the ruler so that its middle is in focus. Then make a photograph. If the middle is in focus, everything is fine. If not, then shims need to be put in. In my camera, there are two strips of film, one strip from 4x5, one strip from 35mm, on each side to put the glass where it needs to be. Together they are the right thickness, and my images are wonderfully sharp!

Dan Fromm
21-Jun-2014, 15:10
What is the serial number of your Speed Graphic. Knowing then it was made could help determine if it should have a Fresnel installed or not.

Good idea, but there were retrofits.

Leigh
21-Jun-2014, 15:32
...You don't appear to be using a Graflex original lens, ie the Nikkor 150mm.
Could that be affecting the focal distance?
No.

You can use any lens with this camera that has a flange focal length (FFL) less than the maximum bellows draw.

Obviously for subjects closer than infinity, the FFL must be short enough to permit focusing on the subject.

- Leigh

IanG
22-Jun-2014, 02:35
Good idea, but there were retrofits.

Also some late models were sold without a fresnel. I'm using one (a Crown Graphic) today, I had to fit the fresnel on the outside to retain the focus register.

It doesn't help that there were Spring and Graflok backs sold with and without fresnels fo quite a few years.

Ian