anamorphic lenses for 16 and super8 widescreen
benj_...@my-deja.com
after reading the article on the 8mm metadirectory about anamorphic
lenses for super-8, i am shopping
around for one (mostly watching auctions on ebay). My question simply
regards the letter designations (ie,
16A, 16C, D, F, H, and probably more) that follow the lens names and
seem to be industry standard. Do
these refer simply to rear thread width and if so, could somebody write
out the specs for me?
Also, are there major differences between projector and camera
anamorphic adapters? Have people had
decent success using camera set-ups that include projector lenses?
any other info you might think relevant would be appreciated.
thanks,
benj gerdes
Sent via Deja.com http://www.deja.com/
Before you buy.
Peter
>>
Also, are there major differences between projector and camera anamorphic
adapters?
>>
Yes.
A projector anamorphic usually can focus to 50 feet minimum, and looses
"sharpness" due to lack of correction for astigmatism, if focused closer.
A camera anamorphic usually can focus to 5 feet minimum, and doesn't loose
sharpness due to astigmatism (but it does loose squeeze when focued very
close).
The main internal difference is a projector anamorphic only has four
cylindrical elements while a camera anamorphic has six or more cylindrical
elements ... and this is just for the adapter portion, not the prime portion.
Also, a projector anamorphic usually is designed for 50mm (2") focal length
prime lens and longer (16mm format) while a camera anamorphic is usually
designed for 25mm or a little shorter prime lens.
JohnW248
> 16A, 16C, D, F, H, and probably more) that follow the lens names and
>seem to be industry standard.
While there doesn't appear to be a standard, the lenses made by Sankor follow
this pattern:
16C has a rear diameter of 42mm, the thread is (I think 40mm)
16F has a rear diameter of 42mm and no thread
16D has a rear diameter of 52mm and is threaded
The Kowa lenses are different
The Vidoscope 16mm 2x lens has the same rear barrel and thread as the Bolex
Moller lens and can be used in the Bolex 16mm Rex set-up
The Kowa 16D has the smaller rear barrel 42mm and is usually threaded
The Kowa 16H is the larger lens with the 52mm rear barrel
The Kowa 8Z was sold for 8mm/Super8 use is a 52mm rear barrel lens (not sure if
it's threaded.
Other lenses will generally fall into these three sizes (39/42/52) except for
the 16mm Panatar lens which is 50mm. The Panavision Superama lens has a 42mm
barrel with it's own threading of the full barrel diameter.
Many other names appear on these lenses since the manufactuers appear to have
custom engraved names on the lenses if the quantity was large enough. You'll
see Films, Inc, ICECO, Singer, Victor, etc.
Bell & Howell eventually sold the Kowa 16D with a built in adpater for the
large threaded barrel lens, but earlier made a rather strange long adapter
which originally was made for the military and adapted to the Jan Projector.
Earlier they made an exception, but rare, Filmorama lens.
The Buhl lenses appear to be Sankor optics in new mounts.
And beware, there are a number of 16F lenses marked Eiki, D O Industries or
Sankor that were part of a government naval buy which have been modified to
three foot focusing on Laird telecines. These were ship board television
stations for the US Navy before they went to Beta cassettes.
John
be...@lostandfoundry.org
name whether the lens is designed for projection or as a camera lens? Are
the sankor and kowa lenses camera lenses?
thanks,
benj gerdes
In article <20000922232245...@nso-dd.aol.com>,
Peter
be...@lostandfoundry.org asks ...
>>
so, I'm still a little confused, is there a way of telling from the lens name
whether the lens is designed for projection or as a camera lens? Are the sankor
and kowa lenses camera lenses?
>>
None of the lenses mentioned are camera lenses; they were indended for
projection.
AFAIK, the only 16mm anamorphic lens actually manufactured for principal
photography was the Bell & Howell Filmorama, and these haven't been made for 45
years, and were too expensive anyway ($595 in 1956 dollars; that's about $7,500
in 2000 dollars).
If you really want a good anamorphic for 16mm principal photography, get a
Bausch & Lomb Type II CinemaScope adapter. About $500, give-or-take.
These lenses were designed for production, will focus closely, and will cover a
35mm focal length prime lens in 35mm (17.5mm in 16mm). Lots of glass ;-)
Those projection adapters mentioned were designed to cover a 2" (50mm) focal
length projection lens, and I'd be surprised if they'd cover even a 40mm focal
length prime lens when used on a 16mm camera.
Peter.
JohnW248
>so, I'm still a little confused, is there a way of telling from the lens
>name whether the lens is designed for projection or as a camera lens? Are
>the sankor and kowa lenses camera lenses?
The Sankor and Kowa lenses can be used for photography. You problem (concern)
will be that these are supplemental lenses and must be mounted in front of your
prime lens. You need to construct a device (like the Bolex adapter) which will
hold the lens so that the prime can be focused. The problem is that if it's
affixed with a screw in filter holder type adapter, the prime front element
will roatate in focusing and thus the anamorphic will not be properly aligned.
You need to focus the prime, then the anamorphic. You need to rely on tape
measures nor visual focus (which can often be "off"). Isco made a 1.5x lens for
still cameras back in the 50's called Iscorama. These came with a proper 50mm
lens for a still camera (Pentax/Nikon, etc) and a 100mm slide projector lens
(Kodak). The lens would stay in alignment with focusing and only the one lens
need to be focused. A "C" mount adapter would make this usable for 16mm
photography.
I've shot with the Panavision Superama lens, having modified the Bolex Rex
adapter to hold the larger barrel lens.
Remember these lenses generally won't focus closer than five feet, but you can
shoot closer by use of diopters.
John
Peter
The "focusing" ring on an anamorphic adapter is not focusing, per se, but an
adjustment for astigmatism.
The indicia on the adapter which is marked in feet (or meters) is that setting
for which a point source of light, at the indicated distance, will have minimum
astigmatism, when refracted through the adapter.
Projection adapters are usually four cylindrical elements and can focus to 50
feet (35mm type) or perhaps somewhat closer (16mm type).
Production (principal photography) adapters are usually six or seven
cylindrical elements and can focus to about 5 feet.
Loss of squeeze is the principal defect when close-focusing a cylindrical
adapter, as these are actually designed for an infinite reproduction ratio
(i.e., these are designed to be "focused" at infinity), and these have the
specified squeeze (usually 2X) when set at infinity, but this squeeze falls off
towards 1X as the reproduction ratio approaches unity.
Optical printer adapters are designed for a unity reproduction ratio (i.e.,
these are designed to be "focused" such that a 1 to 1 dupe is being made), or
close to unity, and these have the specified squeeze (usually 2X) when making
'scope to flat or flat to 'scope recompositions in the same gauge; also for
35mm to 70mm, 70mm to 35mm, or 35mm to 16mm conversions.
Steven J. Weller
be...@lostandfoundry.org writes:
> so, I'm still a little confused, is there a way of telling from the lens
> name whether the lens is designed for projection or as a camera lens? Are
> the sankor and kowa lenses camera lenses?
For virtually all of the S-8 and 16mm anamorphic lenses, the camera
lens and the projection lens are the SAME lens. They are a-focal
devices that are (in theory) not a part of the focus/zoom lens
elements; they just squeeze and unsqueeze the image.
The rule-of-thumb would be to get the one that a) fits your camera, and
b) provides the aspect ratio you're looking for (1.85, 2.0, 2.35,
whatever), and then to get an adapter/stand/mount to hang that same
lens in front of your projector.
--
Life Continues, Despite
Evidence to the Contrary
Steven
Paul H. Cotto
principal photography and mount directly to the camera on a special bracket.
It's the Bolex-Anamorphot 16/32/1.5x made in Germany by System Moller. For
more information on amateur grade anamorphic lenses visit Mr. Bumgartens
page,
http://members.aol.com/Super8mm/Widescreen.html
Hope that helps,
Paul Cotto
"Peter" <peter...@aol.com> wrote in message
news:20000923122558...@ng-df1.aol.com...
>
> be...@lostandfoundry.org asks ...
>
> >>
> so, I'm still a little confused, is there a way of telling from the lens
name
> whether the lens is designed for projection or as a camera lens? Are the
sankor
> and kowa lenses camera lenses?
> >>
>
Peter
>>
I am not sure your answer is correct. I own 2 Bolex lenses made for principal
photography and mount directly to the camera on a special bracket. It's the
Bolex-Anamorphot 16/32/1.5x made in Germany by System Moller.
>>
What's not correct?
The original writer was asking about *projection* 2X adapters being used for
principal photography.
My comments were about the differences between projection and *production* 2X
adapters and the trade-offs encountered in using a projection adapter for
production.
Sure, the Moller system, which is a 1.5X adapter, is a solution for those who
desire a non-conforming (1.5X) lens.
It is possible to made a cylindrical anamorphic which has excellent performance
at most subject to film distances, but these have more elements and cost a lot
more.
See Schneider's current offerings for examples. About $3,200 each, list price.
Paul H. Cotto
meant amateur grade adapters. I am not an expert as you seem to be. I do
understand the limitations of using a projection adapter to shoot with. I
have seen 2X adapters made for shooting though, but mostly for Bolex 8mm
cameras.
Regards,
Paul Cotto
"Peter" <peter...@aol.com> wrote in message
news:20000925123500...@ng-cq1.aol.com...
Peter
>>
Sorry, I didn't see where he was asking about 2X [ anamorphics ] .
>>
The original post listed a number of anamorphic adapters by screw size.
John responded with a list of adapter manufacturers and the screw sizes that
applied to those adapters.
All were projection adapters intended to permit the user to present squeezed
features such as those obtained from Films Incorporated, for example.
Such squeezed features are 2X.
I suppose there was a chance that the original post was in regards to in-flight
motion pictures, which were 1.5X, but that is a very, very remote possibility.
Hence, the original post strongly implied 2X.
<<
I have seen 2X adapters made for shooting though, but mostly for Bolex 8mm
cameras.
>>
Bolex's own adapters were 1.5X.
Bolex did, however, make a special modification for its "octameter" (side)
viewfinder which supported 2X. That modification hasn't been available for more
than 40 years, and I can find no evidence of that finder modification in any
catalog.
Remember, Bolex was once in the service business as well as the manufacturing
business, and it could and would upgrade an older, non-reflex camera to a
reflex camera, although such an upgrade probably wasn't economically justified.
Clive has a pretty comprehensive list of Bolex models and the corresponding
serial numbers. The serial numbers changed when the reflex model was
introduced, and with subsequent models as well, but a reflexed camera kept its
original, non-reflex serial number.
Clive Tobin
I think Paul might be confusing compression ratio with aspect ratio. A
1.5:1 compression/expansion of a 1.33:1 aspect ratio yields a 2:1
aspect ratio.
My writeup of Bolex serial numbers, pertaining mostly to the Reflex
cameras, can be found at http://www.tobincinemasystems.com/page96.html .
Missing is the beginning serial number of the Rex-2, which nobody seems
to know. If anybody has definite information, kindly let me have it and
I will update the pages. Thanks.
--
Clive Tobin
http://www.tobincinemasystems.com
e-mail: clive tobin at liberty bay dot com
Peter
>>
I think Paul might be confusing compression ratio with aspect ratio. A 1.5:1
compression/expansion of a 1.33:1 aspect ratio yields a 2:1 aspect ratio.
>>
Yes, the 1.5X squeeze was specifically selected so that the resulting aspect
ratio was 2.00:1.
1.66 * 1.5 = 2.00.
David Mullen
>1.5:1 compression/expansion of a 1.33:1 aspect ratio yields a 2:1
>aspect ratio.
Also remember that aspect ratio can further be adjusted by print or
projection matting. Since Cinemascope-type anamorphic lenses have a 2X
compression, the 2.39 : 1 projected image means that the image on the print
passes through a matte or gate that is 1.195 : 1. So you could have an
image on a print that gets unsqueezed to 2 : 1 but still end up with a 1.85
or 2.35 image if you could further matte it during projection. Of course,
that's not a standard projection matte, but neither is a 1.5X anamorphic
projector lens...
David Mullen
Clive Tobin
> ...that's not a standard projection matte, but neither is a 1.5X
anamorphic
> projector lens...
The latter might become one, if John Pytlak of Kodak gets his way. He
is presenting a paper at SMPTE suggesting using the scope aperture with
a 1.5x anamorphic to get very close to 1.78:1 aspect ratio with maximum
image quality and light transmission through the gate.