Single Focus Instructions for Anamorphic Projector Lenses

[artiswar]

@ 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.

 

Frankenscope.jpg

 

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

Now that's a pretty set up. Any footage? What diopters do you have back there? Seems we have a similar set up, my footage is just pretty soft.

[tonydtv]

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!

Thanks bud!

I think it's hella productive to hive mind these DIY projects. Who better to play with than a community of filmmakers who thought it was a good idea to strap a projector lens onto their camera?

I've got nothing against the folks selling their wares, I'm sure they will work amazingly well (and judging by the tests, they do). But for those of us who can't afford the thousands of dollars for adapters or iscoramas, a couple hundred on achromats and old wide angle adapters let's us in on the whole "being able to focus my lens" rage.

So let's play people!

[tonydtv]

@ 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.
 
Frankenscope.jpg
 
btw: As I understand the next GH4 Firmware will enable 4:3 Videomodes

Awesome first build! No tape or PVC I see... What's your focusing mechanism? Are you sliding the wide on the rails?

How's the footage?

Where's the footage?

Post some footage.

[tonydtv]

On close up filters vs achromats...

 

Close up filter:

 

 

Achromat:

 

 

Detail:

 

 

Note all the chromatic aberration in the close up filters, and how much softer the edges of the frame are (look at the top and bottom of frame).

[artiswar]

Very interesting results. The abberation is really pronounced with the close up filters.

Surplus Shed glass finally shipped and will be arriving Monday, excited to test. I think the first thing I'm going to try is some type of focusable achromat. We'll see.

[artiswar]

HD should be up soon but here it is.

I'm using plano-convex lens mounted to the front element of my anamorphic. On the rails, I've mounted a plano-concave lens (pretty ghetto set up, but works enough for proof of concept). Moving the rail mounted lens further away gives me closer focus, in fact, pretty fucking close. Sharp as can be too. All I need to do now is figure out the power of the lenses, buy larger elements, and house them. Baby steps.

[tonydtv]

HD should be up soon but here it is.

I'm using plano-convex lens mounted to the front element of my anamorphic. On the rails, I've mounted a plano-concave lens (pretty ghetto set up, but works enough for proof of concept). Moving the rail mounted lens further away gives me closer focus, in fact, pretty fucking close. Sharp as can be too. All I need to do now is figure out the power of the lenses, buy larger elements, and house them. Baby steps.

WOw! This looks really good! When you're focused to infinity, how far apart are your two lenses?

 

Can you list out the ingredients? Lens, camera (FF or APS-C), which anamorphic adapter giving you awesome flares...

[artiswar]

WOw! This looks really good! When you're focused to infinity, how far apart are your two lenses?

 

Can you list out the ingredients? Lens, camera (FF or APS-C), which anamorphic adapter giving you awesome flares...

 

Thanks! Realized I didn't include any of that on here.

The lenses are about 6 inches apart at their farthest (focus point of around 6"), at infinity (this was all interior so it's kinda difficult to confirm) the lenses almost touch, maybe an inch? 

Anamorphic is the second iteration of the 16mm Hypergonar S.T.O.P.. Beautiful flares. Taking lens for the majority of the clips was the Panny 14-140 usually around 50mm on the BMPCC.

I should also mention, the last clip is without this single focus thing. Just an extra clip.

Like I said, these small elements were just a proof of concept. I need higher power lenses (less movement), larger lenses (no vignetting), and a mounting system (zip ties, sticky putty, and adapter rings look terrible)

[artiswar]

Also, anyone with some knowledge about optics, what type of powers should I look for in terms of focal length to minimize the lens movement?

[Martinn]

It's perfect, but no talking about setting.

[tonydtv]

Also, anyone with some knowledge about optics, what type of powers should I look for in terms of focal length to minimize the lens movement?

 

I know for diopters, it's (power/1000mm) = focal length. So a +1 diopter has a focal length of 100mm, a +4 is 250mm, etc.

 

Don't know about the wide angle adapters.

[artiswar]

I know for diopters, it's (power/1000mm) = focal length. So a +1 diopter has a focal length of 100mm, a +4 is 250mm, etc.

 

Don't know about the wide angle adapters.

 

I have the same math. The only thing I'm having trouble figuring out is how the powers interact (ie, what power glass would shorten the distance of movement required to focus)

Just got a hook up with an optician that works locally and has some tinkering toys at his house. Hopefully I'll gain more info there.

[tonydtv]

I have the same math. The only thing I'm having trouble figuring out is how the powers interact (ie, what power glass would shorten the distance of movement required to focus)
Just got a hook up with an optician that works locally and has some tinkering toys at his house. Hopefully I'll gain more info there.

Let us know what you find out!

[artiswar]

Where'd everyone go!

Placed a second order with Surplus Shed after having tinkered with this: http://arachnoid.com/OpticalRayTracer/

Used what was available in reasonable diameters and input the parameters into the ray tracer. Hopefully the pieces I order work out.

In the mean time, it seems like equal, strong dioptric value glass is the key. The stronger the power, the less movement required. Ideally, a concave lens with a power of -25 and a convex lens with a power of +25 should be ideal, just expensive/hard to find. Emailed a Chinese lens manufacturer about making these so we'll see where this goes.

Further looking into the use of wide angle adapters, it seems they're comprised of a negative lens and an achromat which would explain why this works in place of solely a negative lens. I'm thinking a .5 and a +10 diopter might be workable but the travel distances would increase.

[tonydtv]

Where'd everyone go!

Placed a second order with Surplus Shed after having tinkered with this: http://arachnoid.com/OpticalRayTracer/

Used what was available in reasonable diameters and input the parameters into the ray tracer. Hopefully the pieces I order work out.

In the mean time, it seems like equal, strong dioptric value glass is the key. The stronger the power, the less movement required. Ideally, a concave lens with a power of -25 and a convex lens with a power of +25 should be ideal, just expensive/hard to find. Emailed a Chinese lens manufacturer about making these so we'll see where this goes.

Further looking into the use of wide angle adapters, it seems they're comprised of a negative lens and an achromat which would explain why this works in place of solely a negative lens. I'm thinking a .5 and a +10 diopter might be workable but the travel distances would increase.

 

That program's cool! I have something similar on my ipad, although I'm not literate enough in it yet. Any diagrams?

 

I'm still playing around with what I've got in house. I'm planning on building a housing with the elements I have before I feel confident enough to start buying glass...

[artiswar]

Some diagrams!

Here's what I was working with in my last build

 

And here's the order on the way:


As you can see, the change in focal length greatly decreases the amount of travel required from infinity to close focus. The converging rays indicate the focal point. Excited to keep tinkering!

[Matthew Marshall]

Ive been working on this with my LA7200 realize topic has been quiet, but getting nominal success with the LA7200 just got to fit the thing together right. Issue right now is that its a telephoto lens with non fixed front focus. Making work arounds trying to attach to non moving elements further in the lens.

[FrankLad]

Hey guys!

I stumbled upon this thread while researching tricks and workarounds for single-focusing anamorphic lenses.  Initial searches brought me to the "Fokus|Automat" project: Technically very impressive, but bulky and seemingly complicated... and it appears to no longer be in development.  Later I found this thread and was inspired to have a try at focusing with a wide-angle adapter.

I received my 0.6x Wide Angle Adapter yesterday and came up with this short test.
Setup: Blackmagic Pocket + Metabones Speedbooster + Jupiter 85mm f/2 + ISCO UltraStar 1.75x + 77mm Hoya +4 macro filter + 82mm Cavision 0.6x wide angle adapter
(More details in video description.)

Stretched from 1920x1080 to 3360x1080 in After Effects, then exported at 1920x618.

 

 

Currently I'm looking for a large (77mm / 82mm) achromatic diopter, which I hope will minimize chromatic aberration and sharpen things up a bit.

Thanks for sharing your experiments here!

 

 

[FrankLad]

I've received some messages about the setup and thought it might be helpful to post this.

 

 

This is the new non-cardboard housing.  

I'm waiting for my 77mm achromatic diopter to arrive, and will post a new test once I get that.  (Hopefully this particular achromat is good quality... it's both well-reviewed and fairly cheap.  Will talk more about that once I get it.)

 

 

[robbing]

Awesome!

Tried with tele adapter on a Sankor 16D and it works too.

Thank you so much for this thread!

 

I think just need a wide or tele converter with 2 components,the wide and the diopter,dissasemble and use the wide one to get in focus.

I would like to do this with my Lomo square front too. So,the issue is get a huge lenses with the same power (in opposite?) -10 and +10 for example,right?

Perhaps here:

http://www.edmundoptics.com/optics/optical-lenses/cylinder-lenses/