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View Full Version : Looking for thoughts/experience with mounting a big Dallmeyer 8" lens on a LF camera



kymarto
15-Jan-2018, 05:45
Hi folks,
I have been using a Dallmeyer Super Six Anastigmat 8 inch f2.0 lens on a Sony A7RII, which is a huge waste. AFAIK this lens will have an image circle of about 200mm, so I am only using a tiny part of the center of the circle. I used to shoot with an old Speed Graphic, and so I am considering buying another one and resurrecting a cut film developing system so that I can see what this lens is capable of.

The issues are as follows--first this lens weighs about 3.5 kilos, and has a rear barrel diameter of about 88mm. I have a method to mount the lens on a lensboard, but the Graphic board is only 100mm square. If I enlarge the hole in the board, is there going to be enough metal to hold the lens, and can the focusing rail of a SG handle such a weighty beast?

Of course the lens has no shutter, so that is why I think the SG with its focal plane shutter is the only practical way to expose a piece of film. I do not remember the top speed of the SG focal plane shutter. I suppose I am going to have to mount some sort of neutral density filter on the rear of the lens if I want to shoot wide open.

This would be somewhat similar to mounting an Aero Ektar, but this lens is considerably larger and heavier. I don't think the bellow extension will be a problem.

Ideally I would love to put this guy on a 5x7 camera, but I know of no way to mount a shutter with that, so I think I have to settle for 4x5.

Any advice or thoughts appreciated!

Best,
Toby

Dan Fromm
15-Jan-2018, 08:54
If you look hard, you can find a 5x7 Speed Graphic.

I wanted to use the 6"/1.9 Super Six I used to have on my 2x3 Speed Graphic. I never implemented the solution for the Super Six, the lens was just too heavy for walking around with, but have implemented it for several other largish lenses taken from aerial cameras.

If you cross the Dau brothers' palms with silver, SKGrimes will made a cup-shaped adapter that will go on a 4x5 Graphic board. Smaller male end goes through a hole in the board, retaining ring clamps it to the board, larger female end accepts the lens. Then make a spacer (crutch) that will fit between the bottom of the lens' barrel and the bed rail's front cross-bar. Caveat: the adapter may act as a stop, if so you'll have a lens that's somewhat slower than f/2.

And there you will be, if the lens' barrel is slender enough. To find out whether this can be done, lay the lens on the camera's front bed and check whether the lens' optical axis is below the center of the gate.

kymarto
15-Jan-2018, 22:27
If you look hard, you can find a 5x7 Speed Graphic.

I wanted to use the 6"/1.9 Super Six I used to have on my 2x3 Speed Graphic. I never implemented the solution for the Super Six, the lens was just too heavy for walking around with, but have implemented it for several other largish lenses taken from aerial cameras.

If you cross the Dau brothers' palms with silver, SKGrimes will made a cup-shaped adapter that will go on a 4x5 Graphic board. Smaller male end goes through a hole in the board, retaining ring clamps it to the board, larger female end accepts the lens. Then make a spacer (crutch) that will fit between the bottom of the lens' barrel and the bed rail's front cross-bar. Caveat: the adapter may act as a stop, if so you'll have a lens that's somewhat slower than f/2.

And there you will be, if the lens' barrel is slender enough. To find out whether this can be done, lay the lens on the camera's front bed and check whether the lens' optical axis is below the center of the gate.

I have an adapter I am using now that holds the lens and ends 80mm later in a male M65 thread. I think that is long enough not to act as a stop. The main question the becomes whether a lensboard could handle all the weight, and what would happen to the front standard and focusing rail. I could have a shorter one made and ending in any size thread or tube diameter and length, but if you had problems with a 6 inch, the eight inch is going to be problems on steroids.

Dan Fromm
16-Jan-2018, 05:22
That's why you want a crutch. Here https://1drv.ms/i/s!AggQfcczvHGNh10etmk2wHeRewl0 is a link to another ridiculous lens on a 2x3 Speed Graphic. The piece of plastic between the lens' barrel and the outer bed's front crossbar supports the lens, keeps it from destroying the front standard. If the link doesn't work for you, please complain.

If your monster's balance point is too far forward for this approach to work, you can support it with a crutch on a bracket that attaches to the camera's tripod socket. The bracket will have to have a socket for attaching everything to a tripod.

B.S.Kumar
16-Jan-2018, 06:04
Ideally I would love to put this guy on a 5x7 camera, but I know of no way to mount a shutter with that, so I think I have to settle for 4x5.


Perhaps use a Sinar or Packard shutter? People on this forum have adapted the Sinar shutter to various field cameras. I think I've also seen references to the shutter portion of the Super Graphic camera being removed and used as a shutter. This approach would let you use the most suitable camera for this lens.

Kumar

Dan Fromm
16-Jan-2018, 06:17
Good thoughts, Kumar, but I think the Sinar shutters are a little small for the OP's monster. A large Packard would work, but what's the point of using a shutter whose top speed is 1/25 with an f/2 lens?

jp
16-Jan-2018, 06:28
Dan's suggestion for a crutch/stand is about all you can do. I don't think a 5x7 speed is going to have a bigger lensboard. A super-speed does not have a shutter and has a smaller proprietary lensboard. An Anniversary or Pre-anniversary speed graphic 4x5 is going to have the biggest lensboard. You can often use a square metal board rather than a wooden one for more strength. I'm not sure how the the lensmount compares to an Aero Ektar, but the AE fits my camera with very little room to spare.

Alternatively if you have a studio camera with a big 9" lensboard, you could mount a speed graphic as a shutter as I did. https://www.youtube.com/watch?v=pAjyYixKXm8

Tin Can
16-Jan-2018, 06:29
Look here at one working solution.

https://m.facebook.com/groups/6841431147?view=permalink&id=10154895605041148&src=email_notif

Pere Casals
16-Jan-2018, 06:32
I suppose I am going to have to mount some sort of neutral density filter on the rear of the lens if I want to shoot wide open.

Not at all, the Speedy shutter is curtain type, allowing for very short 1/1000 exposures by using a narrow window between front and rear curtain.

Dan Fromm
16-Jan-2018, 09:01
Papi, Speed Graphic shutters have fixed width slits. Just one curtain.