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tonydtv

Single Focus Instructions for Anamorphic Projector Lenses

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Might as well throw this into the anamorphic forum explosion!

 

I came across this focusing solution earlier this year by taking my 20% understanding of comments made on varied forums about optics and vaguely knowledgeably combining elements from the large amount of random glass I've amassed over the years. I don't claim to know much about optics, and I'm certainly no engineer, but this technique has worked when I didn't have the budget to rent a set of Kowas or the like.

 

This is definitely a lo-fi, DIY solution. The other products popping up around the forum are higher quality than this, and really this solution's quality depends on the quality of glass you use. Also, I could be totally wrong about how and why this is working.

 

But if you like to tinker as much as I do, and don't mind a lo-fi aesthetic, then, here:

 

 

(handheld the optics, hence the wobbles)

 

In a nutshell, arrange the following items in the following order:

a. Camera

b. Taking Lens

c. Anamorphic Adapter

d. Achromat

e. Wide Angle Adapter

 

Instructions:

1. Mount camera, taking lens and anamorphic adapter together.

2. Attach achromat to the front of the anamorphic adapter, as close to the glass as possible.

3. Place the wide angle adapter as close to the achromat as possible.

4. Through your viewfinder (and not lens markings) set infinity focus.

5. Move the wide angle adapter away for close focus.

 

At some point you'll start to vignette from the front element getting to far away. If you want closer focus, reset your 'infinity focus' to something closer, like 15ft. That's what I did in the embedded video.

 

There's more notes in the video description, but here's a couple more to get you started:

 

The trickiest part is finding the relationship between strength of the achromat to the strength of the wide angle adapter. I'm sure someone with knowledge of optics will say how. Loudly. Before dropping cash on any achromat, you can use closeup filters to ballpark a strength. In fact, you can use closeup filters, but image quality will suffer. But good if you want to experiment.

 

Also, old DVX or HVX wide angle adapters are a good starter to tinker. 72mm or higher gives you more travel before vignetting.

 

Any questions, ask away!

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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

Well since we're hammering away at this, I'll chime in.

I'm all for the democratization of technology. I saw these (FM whosawhatzit) and immediately started pouring over patents and the such, shortly finding that Iscos are afocal blocks with a variable diopter in the front. So here we have to individuals capitalizing on this "revelation." God Bless America. I, on the other hand, and planning on finding a cheaper solution with some "surplus" (surplusshed.com) and some shoddy test builds. Lucky for me, I have a friend that currently has a satellite (imaging, of course) in orbit and he's more than happy to hash out some details. Once I have some concrete findings, I'm sharing it with the world wide web. Every creative can benefit from this.

 

Preach on @tonydtv!

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Thanks artiswar! Look forward to hearing what you make!

Also, a little more tinkering fun: by doubling the strength of both the achromat and the wide angle adapter, you shorten the length of travel between the two elements to focus. Less vignetting, more close up, keep infinity.

Rock and roll.

Samples soons.

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samples now:

 

 

+10 achromat and two 0.6x wide angle adapters = much shorter travel between achromat and wide angle block = less vignetting, less breathing (but still there) + keeping infinity focus intact.

 

All the shots close focus to between 1 to 5 feet. Also built a wonky PVC housing, so while the elements are aligned better, they're still a little off.

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samples now:

 

 

+10 achromat and two 0.6x wide angle adapters = much shorter travel between achromat and wide angle block = less vignetting, less breathing (but still there) + keeping infinity focus intact.

 

All the shots close focus to between 1 to 5 feet. Also built a wonky PVC housing, so while the elements are aligned better, they're still a little off.

 

beautiful results Tony.  And lovely to see some helpful diy info being posted.  The use of stronger optics in your second test is great.  Anamorphic lens whacking anyone?  

 

In my experiences I would add that using a large diamter century diopter of +7 strength alongside a cheap 'singlet' wide angle adaptor for the pd150 will work great.  As wide angle attachments they are hopeless, but as a source of an off the shelf high quality portion for what you are doing they will be great!

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beautiful results Tony.  And lovely to see some helpful diy info being posted.  The use of stronger optics in your second test is great.  Anamorphic lens whacking anyone?  

 

In my experiences I would add that using a large diamter century diopter of +7 strength alongside a cheap 'singlet' wide angle adaptor for the pd150 will work great.  As wide angle attachments they are hopeless, but as a source of an off the shelf high quality portion for what you are doing they will be great!

 

Thanks!

 

Any of those achromatic diopters work great. The tough part for me has been finding good wide angle adapters. The ones built for certain cameras tend to go soft on the edges or develop mean CA that you have to stop down for. I imagine that's because they are designed for one specific lens. The more generic, focus through adapters have worked best in my experience...

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i have an old +10 red rock achromat sitting here I knew would come in use:)

That is EXACTLY what I used in my build for the second video!

 

Now having bought that ridiculous spinning disk contraption for my XL1 doesn't feel so stupid...

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That is EXACTLY what I used in my build for the second video!

 

Now having bought that ridiculous spinning disk contraption for my XL1 doesn't feel so stupid...

 

indeed.  those +10's were essential for using with redrock dof adaptors I imagine!  I actually grabbed on for development of my 70mm dof adaptor I built a while ago.  It never got used though. 

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large +10 achromats are rare as rocking though.  I think redrocks is the only one ever made in large numbers

Yeah, I know opteka makes them too, but allegedly they are 40mm diameter glass mounted into a frame to fit filter sizes (72mm, 77mm, etc). Probably get vignetting on a 55mm, but maybe fine on an 85mm.

 

There's always edmundoptics.com....

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Yeah, I know opteka makes them too, but allegedly they are 40mm diameter glass mounted into a frame to fit filter sizes (72mm, 77mm, etc). Probably get vignetting on a 55mm, but maybe fine on an 85mm.

 

There's always edmundoptics.com....

 

the opteka's are a joke.  tiny optics in a big ring.  i think the 77mm one has the same optics as the 55mm version

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Well ive been batting this idea around for a while. Trying to use 3d printing to fabricate a lens from LA7200 optics and junked out pieces of old lenses.

Which btw, work better than you'd think. Ive recently spurned my own interest in this with a most recent successful experiment in creating a no CA FD to EF adapter and hunting for infinity focus.

However even from an easy and acessible for most standpoint, I had this sort of makeshift might work setup in mind.

Ef to mft or a larger diameter adapter (havent found quite the right one yet.)
| - magnification lensing element affixed inside this - both to counteract going from ef to mft to ef XD (see blow)
MFT to ef adapter with manual aperture
|
Reverse EF to macro lens adapter
| - Possibly affixing an achromatic diopter here as well to fix any CA
77-72mm step down ring (longer 72mm thread - Makes it stronger
|
Panasonic LA7200 adapter

Not the most elegant solution but it might work?

It would ideally work better with an anamorphic lens that has focusing abilities.

However why not try with the LA7200 - Ive got this one already so.

I have a post in creativity and ideas for the FD to EF lens adapter ill be updating if anyone is interested. Anamorphic is the next step once I get the adapter working.

btw @tondtv I just found edmundoptics randomly a few days ago searching for some obscure search term i never tried. fantastic site looks very promising. I think I was researching glass for Google Cardboard or something lol
 

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Well ive been batting this idea around for a while. Trying to use 3d printing to fabricate a lens from LA7200 optics and junked out pieces of old lenses.

Which btw, work better than you'd think. Ive recently spurned my own interest in this with a most recent successful experiment in creating a no CA FD to EF adapter and hunting for infinity focus.

However even from an easy and acessible for most standpoint, I had this sort of makeshift might work setup in mind.

Ef to mft or a larger diameter adapter (havent found quite the right one yet.)
| - magnification lensing element affixed inside this - both to counteract going from ef to mft to ef XD (see blow)
MFT to ef adapter with manual aperture
|
Reverse EF to macro lens adapter
| - Possibly affixing an achromatic diopter here as well to fix any CA
77-72mm step down ring (longer 72mm thread - Makes it stronger
|
Panasonic LA7200 adapter

Not the most elegant solution but it might work?

It would ideally work better with an anamorphic lens that has focusing abilities.

However why not try with the LA7200 - Ive got this one already so.

I have a post in creativity and ideas for the FD to EF lens adapter ill be updating if anyone is interested. Anamorphic is the next step once I get the adapter working.

btw @tondtv I just found edmundoptics randomly a few days ago searching for some obscure search term i never tried. fantastic site looks very promising. I think I was researching glass for Google Cardboard or something lol
 

Not sure I follow your plan. Would this enable single focusing or would you still have to double focus?

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the opteka's are a joke.  tiny optics in a big ring.  i think the 77mm one has the same optics as the 55mm version

Then again, if the optics are good, it could work for the smaller anamorphics.  I currently have my +10 mounted on my Bell and Howell (the single focus kind, but with the diopters removed), and the smaller opteka may be a smarter fit, ergonomically.

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Just found adding a third 0.6x wide angle adapter (and not changing the + 10 achromat) actually acts as a 0.6x wide angle! And adding a fourth 0.6x makes the whole block a 0.4x-ish wide angle!

 

There are vignetting issues, and the travel is increased, but it looks promising enough to expect a 35mm equivalent anamorphic from it, if not a 28mm too.

 

Also, it's heavy. Very heavy.

 

Footy soon.

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Just found adding a third 0.6x wide angle adapter (and not changing the + 10 achromat) actually acts as a 0.6x wide angle! And adding a fourth 0.6x makes the whole block a 0.4x-ish wide angle!

 

There are vignetting issues, and the travel is increased, but it looks promising enough to expect a 35mm equivalent anamorphic from it, if not a 28mm too.

 

Also, it's heavy. Very heavy.

 

Footy soon.

 

I'd love to see a photo of this setup if you can swing it. Nice results so far.

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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?

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