Cine and photography lenses

What's the difference between "cine" and "photography" lenses?

For instance:
photography: http://rokinon.com/lenses/digital-photo-lenses/35mm-f14
cine: http://rokinon.com/lenses/cine-ds-lenses/35mm-t15

--
Alfred Molon

Olympus E-series DSLRs and micro 4/3 forum at
http://tech.groups.yahoo.com/group/MyOlympus/
http://myolympus.org/ photo sharing site

In article , Alfred Molon wrote:

What's the difference between "cine" and "photography" lenses?

For instance: photography:
http://rokinon.com/lenses/digital-photo-lenses/35mm-f14 cine:
http://rokinon.com/lenses/cine-ds-lenses/35mm-t15

I can't speak about these rokinon lenses specifically, but there are a reason
why cinema lenses are expensive as hell.

When shooting video, you often use focus pull rigs (which the why Cine Rokinon
lens is rigged with a geared focus ring) which need to be calibrated to a
standard across lenses for it to work as it should.

And another one that yo also notice with the Rokinon lenses above is that
cinema lenses always report their t-stop, not their f-stop. T-stop is the
amount of light that reaches the film plane, not the size of the opening like
f-stop. When switching between two lenses in a scene, using the same t-stop
means you get the exact same amount of light through to the sensor, which is
important in film.

There's also focus breathing, you won't want the lens to zoom when changing
focus. For still photography, that's not as much of a problem.

Cinema lenses are also built a lot better. Still lenses need to be light weight
to carry around, while cinema lenses are weather proof and is usually rented by
the crew, so it's durable and a hardware malfunction would be costly for the
crew, this also means that most cinema lenses are highly serviceable as opposed
to most still lenses.

Most cinema lenses comes in sets as well, meaning you get a full range of focal
lengths from Zeiss for instance. They are all matched as far as contrast and
color reproduction is concerned, so you can change between them and get the
same grading process in post.

A lot of cinema lenses are varifocal lenses as well, meaning if you focus on a
subject and then zoom, the focus remains on the same distance during the zoom.
Most still lenses are parfocal, meaning you have to focus again after zooming.

Professional cinema lenses also doesn't vignette. Vignetting in still
photography is undesirable but fixable in post. For motion, vignetting is a lot
more noticeable and also a bit more cumbersome to account for in post.

So, to conclude - a cine lens on a still camera would make the still
photographer wonder why it costs so much, but a stills lens on a cinema rig
would lead to all sorts of problems.

--
Sandman

On 09/03/2016 21:54, Sandman wrote:
[]
A lot of cinema lenses are varifocal lenses as well, meaning if you focus on a
subject and then zoom, the focus remains on the same distance during the zoom.
Most still lenses are parfocal, meaning you have to focus again after zooming.
[]

Other way round:

- parfocal, constant
- varifocal, not constant

--
Cheers,
David
Web: http://www.satsignal.eu

In article , David Taylor wrote:

[]

Sandman:
A lot of cinema lenses are varifocal lenses as well, meaning if
you focus on a subject and then zoom, the focus remains on the
same distance during the zoom. Most still lenses are parfocal,
meaning you have to focus again after zooming.

[]

Other way round:

- parfocal, constant
- varifocal, not constant

My mistake, sorry

--
Sandman

In article , Mark F
wrote:


It used to be (1970's) that a "zoom" lens meant you could zoom
to the longest focal length, focus, and unzoom to get a better focus
then you would by trying to focus at the shorter focal length where
the image was smaller.

some zoom lenses still do that, but with autofocus, that's no longer
necessary.

Oh yeah, the F-stops remained the same also.

many zoom lenses today have a constant f/stop.

Lenses that didn't work that way used terms like variable focal
length if you had to refocus. I don't remember if there was a term
for lenses that didn't keep the same full open F-stop over the
entire range of focal lengths.

the term is called less expensive.

(Of course focal length ratios were in the 1.5 to 4 neighborhood,
not 15 to 60.)

technology progresses.

lenses of today were impossible back then.