Are you getting a vignette with your 67mm .25 diopter? If not, then I don't see any problems.

What aperture were you shooting the above images at?

@leoj I've had mine apart, and it's a very open unit, from back to front. Best place to seal is inside the little protruding hood. But it will be tricky to do so.

I've actually hack sawed the front of mine off now, so it's really simple to tape and seal. Advantages of hacking the front off, are being able to push it up to a circular aperture matte box easier and use wider lenses. My 14-140 now works at about 15mm without vignette now, where previously it was around 17-18mm. I'm also looking at adhesive Velcro for the front, to mount a hi-tech mark 4, 2 slot 100mm filter holder with rotating 105mm ring (for pol).

@plasmasmp I don't think you will struggle in the 2-5m range with many lenses that will require a larger diopter before vignette. The 20/1.7 works with a 72mm diopter taped right up to the front element. The 14/2.5 works well wide open without any diopter.

Hello does anybody have a good solution for less dust to enter in the Inside of the 7200 ?

I heard some tape is good but where to seal it up not to sure

I know, I'm just saying it will work if you rig it up.

Diopters are really difficult at this size. I have a century focusable, which has a 95mm barrel size, with the interior glass 82mm. I can rig my Tokina +0.4 (72mm) into it, but it vignettes below 35mm. I also have the Cokin P101 +1 which is actually a circular 72mm piece of glass inserted into a 84mm plastics drop in filter holder.

I've got a LA7200 coming in a week or two from the US and will let you know how I get on too. My plan is to use the LA7200 in combination with a few other anamorphics depending on the scene.

It's called a Lomo Foton A, and they're as rare as rocking horse shit. I'd then expect to pay a pretty sum for it. There's an 153mm diopter on eBay at the moment (http://www.ebay.com/itm/D-2-5-1-0m-Large-Round-Diopter-LOMO-Zoom-Lenses-153mm-diameter-/250936936509?pt=Camera_Filters&hash=item3a6d01c83d#ht_2298wt_1134) for $750!

The reason you need a diopter for close-up work with an anamorphic lens is to center the convergence between the two anamorphic lens elements inside the adapter. You can regard an anamorphic as a wide-angle adapter that has different magnification factors in its horizontal and vertical directions. When the lens elements are precisely aligned, the anamorphic astigmatism at the plane of focus will coincide in an ellipse of minimum size. When the alignment is off, you'll see the astigmatism stretch out in either horizontal or vertical directions.

To correct the anamorphic astigmatism at close focus, you need to place the diopter in front of the adapter. Placing it behind the adapter will alter the plane of focus of the standard lens you're using behind the adapter, which is probably not the effect you're looking for.

JaecJaec

Where did you find the 105mm macro/close up filter? I've looked everywhere.

With some clever rigging you don't need a diopter.
You can focus however you'd like, and use whatever lens you need.



This guy was supposed to make a guide, it's a shame he didn't.

It seems to me this isn't a good test because you're using a camcorder. The problem with LA7200 and DSLRs or mirrorless cams is shooting close with wide open apatures. If you haven't already seen it the eyepatch entertainment guy on youtube has done a lot of vids with the GH1/2 and the LA7200. He uses a "cheap" $20-30 cokin +1 diopter and he gets close focus within a certain range with wide open lenses, but then he loses infinity focus and can only focus up close, but it works for typical talking close ups.

I also bought a cheap close up filter from Adorama and got good close focus with +1. Click my user name and search my "threads started" I've got some pics of focus with diopter and without.