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anamorphic lenses and diopters


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do diopters behave the same way when used on anamorphic lenses as they do on spherical? what about doublers?

 

thanks.

 

They both work the same as on spherical and you will not risk anamorphic mumps. Diopters and doublers are multiplicative in their corrections so you'll always be keeping the same ratio of horizontal to vertical focal lengths.

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They both work the same as on spherical and you will not risk anamorphic mumps. Diopters and doublers are multiplicative in their corrections so you'll always be keeping the same ratio of horizontal to vertical focal lengths.

 

You know, I wrote that and then thought about it more. I know that isn't the best order in which to do these things. ;)

 

With diopters you probably will introduce a bit of the anamorphic mumps, because you are focused closer than the in-lens corrections will be correcting for. It shouldn't be too much of a problem, though. It should be slight and I can't remember ever shooting faces with diopters on, to be honest, and that is where most people would notice the effect the most. I guess just use the weakest diopter that will do the job and that will minimize the effect.

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You know, I wrote that and then thought about it more. I know that isn't the best order in which to do these things. ;)

 

With diopters you probably will introduce a bit of the anamorphic mumps, because you are focused closer than the in-lens corrections will be correcting for. It shouldn't be too much of a problem, though. It should be slight and I can't remember ever shooting faces with diopters on, to be honest, and that is where most people would notice the effect the most. I guess just use the weakest diopter that will do the job and that will minimize the effect.

 

I just directed a feature shot on the RED with round front Lomo anamorphic primes (a 35mm, 50mm, 75mm, 100mm and 150mm). I was often very close to my subjects and we employed diopters pretty much de rigeur. With regard to ana mumps, I noticed the longer focal lengths tended to fare better. A lot depends on the make of the anamorphic lens itself.

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do diopters behave the same way when used on anamorphic lenses as they do on spherical? what about doublers?

 

thanks.

 

At first, we must know, what kinds of type of optical scheme have anamorphic lens.

This can be lens with front anamorphic adapter and lens with rear anamoprphic adapter.

If we have anamoprhic lens with rear anamoprhic adapter, this is lens can use at spherical and at anamorphic version of assembling and front diopters adapter can use at anamorphic and at spherical version of assembling of lens.

The russian zoom lens 35 OPF-7-1 25-250 at spherical version and 50-500 mm anamorphic version with fear anamorphic adapter had set of diopters for shooting with short distance 0.75m, 1m.

And this is diopters use at spherical and at anamorphic versions of lens.

 

If we told about anamorphic lens with front anamorphic adapter, we need use of front dipter attachmnet with big size round form or big size with square form.

The wide angle anamoprhic lenses do not had diopters attachment, because, will need have big wide angle of view.

 

The russian prime anamorphic lens 35 BAS 4-10 ( 50 mm ) and similar had square front diopter attachmnet for shoot with short distance 0.8 m and 1 m.

 

The very god result have complex optical schemes of front diopter attachmnet with a few glass inside.

 

As of our experience, for macro shoots, we use of round glass LOMO anamorphic lenses 35 BAS2-2 150 mm with hand made front attachment.

We had size of subject of shooting 3x5 sm.

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Anamorphic Mumps?? Can someone post a pic or a detailed description of this optical aberration? I'm unfamiliar with the phenomenon and am going to shoot BMR with both Lomo round fronts and 2 piece square fronts and what PLANNING on possibly using both diopters and split diopters so it's probably something I should know about.

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Anamorphic Mumps?? Can someone post a pic or a detailed description of this optical aberration? I'm unfamiliar with the phenomenon and am going to shoot BMR with both Lomo round fronts and 2 piece square fronts and what PLANNING on possibly using both diopters and split diopters so it's probably something I should know about.

 

http://www.widescreenmuseum.com/Widescreen/wingup1.htm

 

The photos at the bottom of the widescreenmuseum page are panavision's demo to show their superiority to B&L C'Scope lens.

 

Older anamorphics are focused by moving the neg and pos cylinder elements together. This causes the squeeze to change. Newer anamorphics focus by means that do not move the cylinder elements.

 

peter haas, who's a regular on the KonvasOrg was at Fox at the time and says these photos deliberately exagerate the mumps.

See if you can find his posts in the Konvas archieves their & in the Google group 'rec.arts.movies.tech' .

 

The problem would show up in the square fronts when focused close, but shouldn't be as bad as the Panavision anti-CinemaScope demos. The round fronts use newer focusing, the front spherical lenses act as a variable dioptre. as in Hawks and Technovison.

 

yours in TohoScope,

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