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tonydtv

Single Focus Instructions for Anamorphic Projector Lenses

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http://tinypic.com/r/33di4o2/8

Found this. Turns out, separating the wide angle section from the macro section and placing them in front of the anamorphic, moving the wide bit further from the macro bit allows me to focus. Essentially a wide angle and a diopter packaged together, yes? Also, I'm not quite sure why (maybe the hand held testing) but infinity was somewhat fuzzy. Any input on all this?

 

Awesome! So when you move the wide further away, does it focus closer or further?

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EOSHD Pro Color for Sony cameras EOSHD Pro LOG for Sony CamerasEOSHD C-LOG and Film Profiles for All Canon DSLRs

More fun footage. Didn't do the 3x or 4x of the wides, mainly because of the logistics of safely mounting that much weight to the front of the lens. So here's a build with a different taking lens (43-86mm nikkor, fixed at 86), a different anamorphic adapter (Bell & Howell single focus anamorphic w/ focusing diopters removed [dat flare tho]), and a better PVC housing. Sorta.

 

 

Actually, the first few clips were before I got the pvc snug, so its free-lensy. Majority of close focus shots were between 1 and 5 feet. The super close shot of the pup at 1:25 was inches away.

 

As requested, pic of the build:

 

r1lpqq.jpg

 

The anamorphic adapter is held on by tape, not the strongest connection. Had to cradle the anamorphic block and the taking lens in the same hand just in case they came apart. Even with my other hand handling the wide angle block, I didn't want to risk the stress more glass would've put on the build, so I held off on the additional wide angle adapters. Next time!

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Oh alright, here's some stills of four 0.6x wide angle adapters stacked against a +13 diopter block (+10 achromat and a +3 achromat) on the 43-86mm nikkor, set to 86mm. Its equivalent to a 30mm anamorphic lens.

 

1e2o83.jpg

 

Blue is 2.40:1 crop, so vignetting is not an issue going this wide.

 

Top is a bit soft, but I imagine that's due to the achromats: I have them out of their housings and stacked glass on glass, and with the curved surfaces they don't align all that well by hand.

 

Also, very heavy, very awkward in my current tape and PVC build. Working on that.

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IMO, wide angle lens contains a +? diopter as rear lens, so many of them can be screwed out and used as + diopter lens for close focus.  So to reduce using lens, try to get rid of some and keep minimum lens, the powerful one.  Then the pictures quality is the best.  I know, wide angle works well, but taking lens should use longer focus to get higher resolution, less crop and keep the same widescreen view, which depends on anamorphic lens with wide angle attachment.

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Awesome! So when you move the wide further away, does it focus closer or further?

Moving the wide angle away gets closer focus.

Building on this, close focus seems easily attainable (at 1.7 on my Minolta glass, it's a bit fuzzy) but infinity is not quite there. I think it may be due to the fact that I can't get the smaller macro lens close enough to the wide angle bit. Any input?

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Moving the wide angle away gets closer focus.

Building on this, close focus seems easily attainable (at 1.7 on my Minolta glass, it's a bit fuzzy) but infinity is not quite there. I think it may be due to the fact that I can't get the smaller macro lens close enough to the wide angle bit. Any input?

 

The macro lens (I assume a single element diopter and not an achromat?) is too strong to get infinity focus. The strength of the diopter moves where infinity focus is. A stronger diopter moves infinity back, a weaker one moves it forward.

 

So right now, your diopter is so strong that for the wide angle adapter to attain infinity, it would have to go behind the diopter, aka, impossible. If you choose a weaker one, infinity will move forward, ideally in front of your diopter where your wide angle adapter can go without breaking the known laws of physics. Here's a little diagram to illustrate:

 

ezewk0.png

 

I suggest buying a cheapo set of close-up filters/macro filters/diopters that come in +1, +2, +4, +5 sets. While they won't be sharp, you can fine tune infinity focus, and they'll let you know what strength achromat you should buy if you're so inclined.

 

Also, your image is fuzzy because of the quality of the macro/diopter lens; it's probably a single element diopter. An achromat (a two element diopter) will make your image much much sharper. It may also be your wide angle adapter; is it multi-element?

 

Or you could stop down the lens, but where's the fun in that?

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Wide angle seems multi element, as does the macro element, unfortunately too strong. I threw an old 10+ diopter in and the focus throw seems about right. Terrible blur due to the single element, I assume. I've got some Surplus Shed glass coming in, so I'd rather hold off and play with that until I splurge for a +10 achromat. Anything vintage that is achromatic with that kind of power?

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So where does the focus take place?


Like I said more suitable for a Kowa build or adapter that has focusing built in. Probably for the LA7200 directly behind the adapter although using a 3d printer to rehouse the LA7200 in a cylindrical focus housing would probably work best.

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The wide angle seems like a lot to fix within the lens.

Although in the 28-80mm lens I took apart there is a separate element that seems like it could fix the spherical distortion if a wide angle. That one is a pretty thick lens part so I think its more than one element possibly a 2 achromatic.

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Wide angle seems multi element, as does the macro element, unfortunately too strong. I threw an old 10+ diopter in and the focus throw seems about right. Terrible blur due to the single element, I assume. I've got some Surplus Shed glass coming in, so I'd rather hold off and play with that until I splurge for a +10 achromat. Anything vintage that is achromatic with that kind of power?

 

+10 sounds right, considering that what I used on Build 2 was two 0.6x wide angles stacked, which equals 0.36x wide angle block, pretty close to your 0.4x.

 

Blur may be from using 0.4x... I used a 16x9Inc 0.4x wide angle adapter and I would lose focus on the edges unless I stopped down like mad. Stacking weaker power wide angles might work better, or at least has from my experience.

 

The achromat will help tho. I remember back during the redrock craze, people were DIY'ing achromats using old binocular glass. I think it was easy to get a +7 achromat out of them. Google "achromat binoculars dof adapter". 

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Like I said more suitable for a Kowa build or adapter that has focusing built in. Probably for the LA7200 directly behind the adapter although using a 3d printer to rehouse the LA7200 in a cylindrical focus housing would probably work best.

 

Seems like focus would still only affect the horizontal plane if you're focusing on the anamorphic only, although I don't know enough about optics to say one way or the other...

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Wide angle seems multi element, as does the macro element, unfortunately too strong. I threw an old 10+ diopter in and the focus throw seems about right. Terrible blur due to the single element, I assume. I've got some Surplus Shed glass coming in, so I'd rather hold off and play with that until I splurge for a +10 achromat. Anything vintage that is achromatic with that kind of power?


Would you be able to use an achromatic then a regular non achromatic. Stack them to get the power you need and the CA fix?

Might be cheaper.

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Would you be able to use an achromatic then a regular non achromatic. Stack them to get the power you need and the CA fix?

Might be cheaper.

 

My thought process here is that when I get my Surplus Shed glass I'll be able to do that very thing. 

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Here's the 30mm (ish) anamorphic!

She is a BEAST. Weighs about 6 pounds. My PVC and tape housing is not strong enough to hold all the glass securely so the elements do get misaligned in a few shots. BUT, as a proof of concept, I'm happy.

Focus travel is probably a half inch or so between infinity to about an inch. The close focus shots in the clip are about an inch away.



Working on an engineering solution to mount this on a 70-200 Canon zoom and have a 30 - 80 anamorphic zoom!

Also, a programming note: I'm pretty sure I'm wrong about my redrock +10 achromat, I think the it's a +8 and NOT a +10.

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Thanks so much, this has been so interesting & in keeping with the spirit of an open source community - in a time where people just seem to want to take take take, rather than give!

 

This Anamorphic Forum has always been about people helping/giving advice to others who are passionate about Anamorphic Lenses or to those that are just discovering them.

 

I tip my hat to you - especially in light of the vitriol displayed in another thread!

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@ tonydtv Thanks for the inspiration.

 

Here is my test assembly with Nikon 50mm/Schneider Cinelux 2x/+10 Diopter and 0,43 wide-angle.

Awaiting some Marumi Achromats for further testing.

 

post-35412-0-87285000-1411115102_thumb.j

 

btw: As I understand the next GH4 Firmware will enable 4:3 Videomodes

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