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Thinking about the LA7200, oh god diopters


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 So the only thing really holding me back on buying an LA7200 is diopters.  I mean, I've seen what the Kenko +0.3 diopter can do ([url="http://bit.ly/Vw0zMp"]bit.ly/Vw0zMp[/url]) but it's pretty hard to find.  I'm willing to shell out for a Schneider 138mm +0.5 diopter ([url="http://bhpho.to/JzwJBv"]bhpho.to/JzwJBv[/url]) but I'm still just a little uncertain.  I was hoping to get 35mm (equivalent) out of it, so maybe I do have to go all-out, but maybe there's a better solution out there?

There's also a Canon 105mm close-up adapter on ebay ([url="http://bit.ly/SWiKMJ"]bit.ly/SWiKMJ[/url]) that I know people use, but have no idea about the power...

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This worked for me (at a fraction of the cost of the other filters that you are talking about): [url="http://www.eoshd.com/comments/topic/1212-panasonic-ag-la7200-diopter-mounting-solution/"]http://www.eoshd.com/comments/topic/1212-panasonic-ag-la7200-diopter-mounting-solution/[/url]


I actually saw your thread!  However, I should have wrote 35mm (35mm equivalent), which would be the 17.5mm on the GH2...  which would probably vignette. 

 

Am I pretty much boned here, or do you of any other wide-angle options (or am I crazy for going that route to begin with)?

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LA7200 from what I have seen is no better than the century 16:9, yet people pay almost twice the price for them!  go with century and have enough to a tokina left over!

 

century + tokina on 28mm f2.8 wide open, aps-c sensor:-  vimeo.com/52472870  I have a few more samples of the century on my profile.  If you find a la7200 for the same price as the century then go for it, otherwise, it's no better from what I have seen.  Both need a smaller sensor to work at their best.  

 

Someone for gods sake try one of them on a ikonoskop or a rx100

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The lenses I use have 72mm and 77mm filter threads, though.  Not saying I can't buy a step-down ring, but would the century cover those lenses (the Rokinon 24mm and 35mm, among others).  Otherwise I'd be all over the Century.

 

I missed the ebay sale, but the shipping was Europe only when I looked.

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The lenses I use have 72mm and 77mm filter threads, though.  Not saying I can't buy a step-down ring, but would the century cover those lenses (the Rokinon 24mm and 35mm, among others).  Otherwise I'd be all over the Century.

 

I missed the ebay sale, but the shipping was Europe only when I looked.

 

I think you might want to rethink your plans.  though you wont get any vignette on the 35mm (and very little with the 24mm)   f1.4's are a no-no with anything focus through like the century or la7200.  just get something like a 35mm f2.8 and that will be fine.  you're only lining yourself up for disappointment otherwise.  IMO 

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I think you might want to rethink your plans.  though you wont get any vignette on the 35mm (and very little with the 24mm)   f1.4's are a no-no with anything focus through like the century or la7200.  just get something like a 35mm f2.8 and that will be fine.  you're only lining yourself up for disappointment otherwise.  IMO 

 

Thanks for the heads up.  I was under the impression that shooting wide-open isn't a good idea - its just using the lenses I already have as compared to buying a whole new set.  Would it be cheaper to buy a whole new set?  Probably....

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I think you might want to rethink your plans.  though you wont get any vignette on the 35mm (and very little with the 24mm)   f1.4's are a no-no with anything focus through like the century or la7200.  just get something like a 35mm f2.8 and that will be fine.  you're only lining yourself up for disappointment otherwise.  IMO 

 

That's what the Tokina is for, in addition to CU shots.  It sharpens up apertures in the F2 and bigger range.  In my tests so far it looks like I can get usable sharpness opened fully to F2 on my Nikkor 24mm, F2.5 on my Nikkor 105mm and F1.4 on my Nikkor 35mm, with the Tokina, with my Century Optics.  I've seen videos online that look great with the 20mm Lumix pancake lens fully open too, with the Tokina.

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I suppose I was assuming the thread starter is using aps-c.  however, gh2 with smaller sensor will work better with bigger apertures.  I'd still question the usibility of the century any wider than f2.8 in close to medium distance - sharpness at infinity is easier it seems.  -but in most cases I never managed anything wider than f2.8 personally

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I suppose I was assuming the thread starter is using aps-c.  however, gh2 with smaller sensor will work better with bigger apertures.  I'd still question the usibility of the century any wider than f2.8 in close to medium distance - sharpness at infinity is easier it seems.  -but in most cases I never managed anything wider than f2.8 personally

 

Challenge accepted.  I find I don't need the diopter at F2.8 unless I need really sharp focus at well under a meter, ECU distance from the camera, at least not with my 24mm Nikkor.

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Yeah I was talking about APS-C.  I have some friends around, but no luck finding old diopters...  In a few weeks I'll post some results with the LA7200 and the Schneider diopters.  At least I figured out that they come in 115mm, which -should- be more then enough.

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I use the LA 7200 professionally all the time. [I shoot on GH2 & AF102]

Glass config: LA 7200/Kenko 105mm .03 Close Up Filter/Voigtlander 17.5mm f.95

I must say this setup hits some sort of major 'sweet spot'! I haven't taken off the Kenko .03 filter for months.  

To me the focal range is astonishing and I have even picked up [carefully composed] shots @ f.95!

I own a lot of glass but nothing comes close to the Voigtlander 17.5mm f.95 & Voigtlander 25mm f.95[which I use with 

an Isco 54 on my AF102] 

I bought the Kenko on Ebay for under 300 bucks - for my money this setup is worth chasing up! 

ps my other favourite LA 7200 set up is: LA 7200/Kenko 105mm .03 Close Up Filter/Olympus 14-35mm f2[crops@20mm]

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I wonder if some of the variation in user experience with these anamorphic adapters has anything to do with the way folks are rigging up their mounts to overcome the bayonet mount (at least on the Century).  I'm using a step-up ring sandwiched between the rear element and the back of the lens.  It fits perfectly around the back element and essentially gives it threads to fit up perfectly into a 52mm Nikkor.  You wouldn't know it had been modified at all if you didn't know these things didn't come normally with threads in back.

 

I saw one example online where a fellow was doing something like this but with a slightly larger step-up ring being held in place by four washers wedged underneath the edges of the rear of the lens.  He then used a step-down ring to mount his modified anamorphic to his taking lens but now I'd expect there to be slightly more distance between where the rear of his anamorphic sits and where the taking lens is designed to expect something to be mounted, or does this tiny difference matter at all?

 

For that matter, does it matter if the diopter/achromat in front of the anamorphic has an adapter ring or more of space between it and where it would normally be seated if some form of home brew mounting method didn't have to be engineered?

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That's an interesting consideration BRoades - especially if the anamorphic adapters in question are single glass element designs - are we stumbling across augmentations [in the case of using some low powered close up diopters] that unleash the quality of earlier multi element anamorphic adapter designs? For me the holy grail is a 112mm + .025 Achromat filter.

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the panasonic is a posher version of the century and optex and generic design.
posher because panasonic had better quality controls and higher spec.
but still variations on a theme.

the designs of these may seem simple but they are complex air spaced cylindrical achromatics.
designed on a super computer and optimised for various small sensor but semi pro camcorders.

the poor quality relates more to what they where designed for and the variable factory quality control.
and like most anamorphics missalignement of front and back optics.

although these type are single element they are anamorphic cylindrical achromatic designs.
achromatic like thick doublets in quality anamorphics just different recipes.
they are not just a couple of bits of glass.
if they had of been designed with movable optics quality would of improved a lot.
my guess is the slr magic test lens will be a variation on the century panasonic system.
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although these type are single element they are anamorphic cylindrical achromatic designs.
achromatic like thick doublets in quality anamorphics just different recipes.
they are not just a couple of bits of glass.
 

 

To be achromatic they must have two elements at least. The stretch factor is the ratio of the rear to the front focal lengths. By keeping the ratio fixed and reducing the front and rear focal lengths the spacing between afocal and 2m focal length of the compound lens can be made to be about 1-2 mm. This works for 6mm sensors pretty good within a zoom range of 10x. 

 

Using them with 35mm lenses opens the door to softness and CA

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