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Why there is no running F aperture on Epic's monitor with CP.2?

A

Alexey Datsenko

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Could you tell me please why there is no F aperture shown on Epic's monitor with CP.2?
 
because CP.2 don't transmit i/data because it's not build in
 
Zeiss CP.2 lenses can't provide f-stop information to the camera they are attached to. No electronics in the lens, no data pins in the mount, therefore no information for a camera to display.
 
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How can it be? The most popular lens for Epic and no any aperture information on monitor?
 
Zeiss didn't design the lenses that way. Not an Epic issue. Zeiss would be the people to complain to in this case.
 
How should the Epic know if the lens doesn't tell the camera?

facepalm_picard2_reasonably_small.jpg
 
Alexey, as Mark and Max said, the Zeiss CP.2 are full manual lenses with no electronic connections to the camera. This is how the lens is designed.

This isn't a camera limitation, this is a lens design issue.

This is the case for many professional cinema lenses as well.
 
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Thanks guys! So what lenses also don't show aperture?
For example with Zeiss ZE it is very useful to see it
 
Alexey Datsenko said:
Thanks guys! So what lenses also don't show aperture?
For example with Zeiss ZE it is very useful to see it
Click to expand...

Only modern electronic lenses that are supported via the Nikon and Canon mounts. Pretty much any modern Canon and Nikon still lens as well as Tamron, Sigma, Voigtlander, etc.....

Manual lenses do not and will never support communicating with the camera.

Some PL glass professional cinema lenses do have electronic communication that may or may not be supported depending on communication type. And of course new lenses that are released may support it as well.
 
In PL mount the RED zooms (18-50 & 50-150) transmit data to the camera; so you see Tstop & focus on the monitor and in the meta data. The pins on the PL mount are set-up in the fashion of the Cooke i/ system, so none of the Zeiss / ARRI lenses will send data.

G.
 
Just as an example, the Rokinon/Samyang lenses, being fully manual, don't show lens info either.
 
Nikon has a way to display this information for lenses without electronics.

When you move the lens aperture ring, a lever on the camera body is moved. Your camera displays f/0 at max aperture and changes in whole numbers (f/1, f/2, f/3) as you stop down. I'd rather do a bit of math [max aperture is 2.8, f/2 means plus two stops, I must be at f/5.6] than stop shooting and look at my lens.

The newest Nikons even allow you to enter your lens's max aperture (and focal length, for EXIF posterity) so the camera can do that bit of math for you and display real apertures.

I'm really shocked no one ever thought to include such a system in the PL mount.
 
Lee Saxon said:
Nikon has a way to display this information for lenses without electronics.

When you move the lens aperture ring, a lever on the camera body is moved. Your camera displays f/0 at max aperture and changes in whole numbers (f/1, f/2, f/3) as you stop down. I'd rather do a bit of math [max aperture is 2.8, f/2 means plus two stops, I must be at f/5.6] than stop shooting and look at my lens.

The newest Nikons even allow you to enter your lens's max aperture (and focal length, for EXIF posterity) so the camera can do that bit of math for you and display real apertures.

I'm really shocked no one ever thought to include such a system in the PL mount.
Click to expand...

It is substantially more difficult as there are no click-stops on a PL mount lens (well, most PL mount lenses at least). Also, since the body does not control the aperture (i.e. there is no lever like in the Nikon bodies), there is no way to get the data except through a protocol like the Cooke/i technology.
 
I would think F-stop readout using any F-mount lens with a AI lever on the Red Nikon mount should be possible with a firmware update. The Red mount has a motor that engages the lever on the lens. AFAIK lever position on the lens is consistent across all AI lenses (including G lenses, which still need the lever). So Red would just need to ask the motor in its mount to give feedback on its position and voila!, F-stop readout on screen. May not be exact due to tolerances and wear between lenses, but very close.

There are some assumptions in this reasoning on my part. Corrections welcome.

If the feedback loop relies on the in-lens chip and there is no way of getting feedback from the in-mount linkage, then this won't work.

Also, I don't know if CP.2 lenses have the AI lever, so this may be a little off topic.
 
Steve Wake said:
Also, I don't know if CP.2 lenses have the AI lever, so this may be a little off topic.
Click to expand...

Zeiss CP.2 do not. They are not (specifically) Nikon lenses. One of their features is an interchangeable lens mount that allow the lens to be configured as one of 5 different camera interfaces (PL, EF, F, E and MFT). This involves removing the back end of the lens and replacing it with different mounting hardware.

There are no electronics/data pins, or mechanical iris linkages to a camera body in this line of lenses. They have manual focus and iris rings, and are not designed to be remotely controlled or sensed by any camera bodies they are attached to.

If you are using the RED DSMC Nikon lens mount and an F-mount lens listed in RED's compatibility list, then your assumptions are correct: a Nikon lens supported in firmware would have the mechanical iris lever mapped out and would provide an indication of where the current f-stop of the lens is at.
 
The RED lenses I bought last month - 300mm prime and 17-50mm zoom don't have i-pin communication either therefore no F-stop or focus distance information on LCD.
 
swan n said:
The RED lenses I bought last month - 300mm prime and 17-50mm zoom don't have i-pin communication either therefore no F-stop or focus distance information on LCD.
Click to expand...

None of the RPP lenses have the pins / lens data - only the original RED zooms 18-50 & 50-150
 
Is it the same case with most PL cineprimes?

Super Speeds, Ultra Primes, Master Primes?
 
My old 18-50mm RPZ does and I love it for doing tests when I don't have a clicker. Aperture speed shows up as metadata in RCX. Pretty cool.

swan n said:
The RED lenses I bought last month - 300mm prime and 17-50mm zoom don't have i-pin communication either therefore no F-stop or focus distance information on LCD.
Click to expand...
 
Will Keir said:
Is it the same case with most PL cineprimes?

Super Speeds, Ultra Primes, Master Primes?
Click to expand...


Master Primes & Ultra Primes have the Arri LDS system of electronic contacts and send info back to the Alexa - But RED PL mounts only have Cooke i/ pins in them. Cooke & Arri chose completely different pin placement (Cooke pins are at the top - Arri are at the side) so they are incompatible. Shame really because it forces camera companies to choose one or the other.
 
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