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Old September 14th, 2006, 09:18 AM   #1
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not shooting straight

Before I bother quyen with this has anyone had an issue where there letus is shotting kinda crooked out of the lens like instead of using the middle of the lens it's shooting off to one side or another? I haven't hear anyone else talk about this yet, but mine is doing that which is making having a level shot almost impossible.
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I have a dream that one day canon will release a 35mm ef to xl adapter and I'll have iris control and a 35mm dof of all my ef lenses, and it will be awesome...
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Old September 14th, 2006, 10:06 AM   #2
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Could you advise what camera type you are using?

What Letus35 version are you using?

Is your Letus35 hanging off the front of your camera via its filter thread or is it supported on a brace or rods system.

It doesn't take much of a bend along the span between the camcorder and the GG with any adaptor to put the projected SLR optical centre out of alignment with the camcorder optical centre.

The VX2000/PD150/VX2100/PD170 camera family has an offset optical centre-axis relative to the CCDs. This does not adversely affect performance in normal circumstances but can make setting up home-made adaptors a little difficult.

That said, I must confess I have never tested the Letus35 for axial alignment.
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Old September 14th, 2006, 10:19 AM   #3
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I'm using an xl-h1 it's the letus flip enhanced xl or thereabouts. I got a hold of quyen and he seems to think it might be a mirror that needs readjusting. Which I guess varfies that there is a problem.
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Old September 14th, 2006, 11:02 AM   #4
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Nick.


As Quyen describes, a mirror could be the issue.

I have been playing with a Letus flip for XL recently and very much like the look of the Canon images.

There is quite a bit of compliance in the section from XL1 lens mount via Minolta relay lens to the mirror flip module and a lot of weight with lots of leverage over that XL1 mount.

The rear tube may have moved on the shoulder were it is bonded to the flip module. Watch this because it may come off if there have been knocks or impacts during transport. Have a close look. It should not be too hard to spot disturbance to the bonded joint.

We went with a brace arrangement to take the load off the XL1 lens mount and the all the jointwork in the adaptor. This is a re-assurance and also relieves any stiffness in the relay lens focus action.

Except for the added hardware with sharp edges to mutilate the collarbone, it makes the whole show more user friendly for handholding.

In this case it is a rods based autocue mount. There was made, a close fitting collar which goes over the front tube of the Letus35 and a small thumbscrew to grip the tube. (haven't got the thumbscrew yet but that is the intention. A standard screw suffices for the moment.).

This screw must be able to be loosened to enable backfocus as the whole Letus35 body moves away or towards the XL1 when backfocus is initially set and must be free to slide inside the collar which is rigidly mounted to the rods. After backfocus is set it is re-tightened but not too much because it will injure the tube.
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Old September 14th, 2006, 11:44 AM   #5
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Bob,

Haven't really used it that much so I think it must have happened in shipping, I also noticed something funny without the lens on when I first hooked up the adapter so I'm betting that there was jsut some sort of issue there. the relay lens seemed eally foggy when fully open so I'm wondering if it's not just some sor tof bad really lens or something.

I'm interested in the mount that you have set up I don't think I quite followed everything from your decription though. I've heard of people using a cavision mount to hold the adapter in place, is it similar to that?
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Old September 14th, 2006, 11:40 PM   #6
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The autocue mounted up to a rod arrangement generally similar to Cavision which was fixed to a sort of universal baseplate with several tripod screw holes in two sizes. The rods centres are 60mm apart, the rods themselves 12.7mm thick (1/2").

Wide open, the relay is a bit soft on the specimen I have been playing with. Best if you can keep it in the ballpark of f5.6 and use camcorder gain or the SLR lens aperture for light control. If you have to open the relay lens wider than say f4, then you probably need to add light to the scene with lamps or a reflector panel.

I think I recall previous posts where there was reference to the relay lens aperture on an earlier production having been limited to an optimum range. The ability to open the lens all the way I think may have been a response in subsequent production to user requests.
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