Focal Length Conversions

[Daniel Soderberg]

I apologize in advance because I'm geussing this question has been asked before, but from what I understand already, my current DSLR set of lenses (C/Y Zeiss lenses converted for my Canon 5D), will act like longer focal lengths on the Red One because of the sensor difference (going from FF to S35). (my Zeiss 50mm will act like an 80mm -1.6x crop). Is this correct?

Will lenses made for film cameras/the Red One like the Zeiss superspeeds (50mm) act the same way (as an 80mm) like my C/Y mount Zeiss 50mm on the Red?

(Trying to be careful with my wording because I do understand that a 50mm is a 50mm no matter what you use it on, it is just that the field of view changes).

 

[David Mullen ASC]

I think you are confusing yourself a bit whenever you put things in terms like "a 50mm is an 80mm on a Super-35 camera", but yes, a 50mm lens is more telephoto in view on a S35 sensor than it is on a FF35 sensor. Doesn't matter who makes the 50mm lens, the only difference between two 50mm lenses could be if one doesn't cover a larger sensor without vignetting if designed for a smaller sensor. But the field of view between two 50mm lens is the same on the same size sensor.

 

[Daniel Soderberg]

I think you are confusing yourself a bit whenever you put things in terms like "a 50mm is an 80mm on a Super-35 camera", but yes, a 50mm lens is more telephoto in view on a S35 sensor than it is on a FF35 sensor. Doesn't matter who makes the 50mm lens, the only difference between two 50mm lenses could be if one doesn't cover a larger sensor without vignetting if designed for a smaller sensor. But the field of view between two 50mm lens is the same on the same size sensor.

Thanks for the response David.

Yes, I understand that the lens doesn't 'become' an 80mm, that's why I was careful to say it 'acts' like an 80mm.

So the same things goes then for instance for the Zeiss Superspeeds in that the 18mm Superspeed will act like a 28.8mm on the Red One (in the same way the 18mm C/Y Mount Zeiss lenses made for DSLRs will act)?
(I ask this because I am considering selling my C/Y Zeiss and buying a set of Superspeeds).

Thanks.

 

[David Mullen ASC]

Thanks for the response David.

Yes, I understand that the lens doesn't 'become' an 80mm, that's why I was careful to say it 'acts' like an 80mm.

So the same things goes then for instance for the Zeiss Superspeeds in that the 18mm Superspeed will act like a 28.8mm on the Red One (in the same way the 18mm C/Y Mount Zeiss lenses made for DSLRs will act)?
(I ask this because I am considering selling my C/Y Zeiss and buying a set of Superspeeds).

Thanks.

It's only from your perspective -- from my perspective shooting Super-35, an 18mm acts like an 18mm! Yes, an 18mm is more telephoto in view on a Super-35 camera than it is on a FF35 camera. And an 18mm is an 18mm, whether it is a Zeiss, Cooke, Canon, Leica, etc. -- the view is the same on the same sized format.

 

[Jerry Creaney]

Not sure If this is the appropriate place for this post Has any one tried fitting a Red 18-85 Zoom to Panasonic AG-AF100 I'm thinking the lens will cover the sensor (21.6 mm Diagonally ), not sure about the mechanical requirements on the Red Zoom

 

[Peter Strietmann]

I would strongly encourage you to get the MatchLens app. "It computes the equivalent lens focal length to produce the same field of view between two cameras with different aperature/sensor sizes." I have no commercial relationship with the company, just a happy customer.

http://web.me.com/donmatthewsmith/Site/MatchLens.html

 

[Steve Das]

Check this out...

Check this out...

Check out Abel Cine's field of view comparator

http://www.abelcine.com/articles/index.php?option=com_content&task=view&id=548&Itemid=45

http://www.abelcine.com/fov/

 

[Uli Plank]

Has any one tried fitting a Red 18-85 Zoom to Panasonic AG-AF100 I'm thinking the lens will cover the sensor (21.6 mm Diagonally ), not sure about the mechanical requirements on the Red Zoom

Not tried yet, but we have both an AF101 and the RED zoom. First thing I notice is how light the AF101 and it's bayonet is and with any lens heavier than the camera itself I'd rather get a support for the lens and attach the camera to it…

 

[Daniel Soderberg]

Another question about focal lengths:
Will a wide angle lens (lets say 18mm) made for an S35 sensor have less distortion (fish eye look) then a wide angle lens made for a FF sensor, because there is less sensor that it has to cover?
I ask this again because I am considering buying either Zeiss superspeeds or Contax mount zeiss lenses and I can see that some of the Contax mount (made for FF still cameras) lenses suffer from distortion, and I wonder if the lens will suffer less if it is made for a smaller sensor (S35).
Hope that makes sense.

 

[Daniel Soderberg]

Bump!
Is bumping of an unanswered question allowed?

Anyway, I still have this (not so intriguing) question I'd like to figure out:
Thanks.

Another question about focal lengths:
Will a wide angle lens (lets say 18mm) made for an S35 sensor have less distortion (fish eye look) then a wide angle lens made for a FF sensor, because there is less sensor that it has to cover?
I ask this again because I am considering buying either Zeiss superspeeds or Contax mount zeiss lenses and I can see that some of the Contax mount (made for FF still cameras) lenses suffer from distortion, and I wonder if the lens will suffer less if it is made for a smaller sensor (S35).
Hope that makes sense.

 

[Michael Olsen]

In my limited experience, lenses that provide a similar field of view for different formats have similar degrees of distortion. In other words, from my experience, a 100-degree FF35 lens and a 100-degree S35 lens will have a similar image.

Of course, that also depends heavily on the specific lenses used - some Nmm lenses will have lots of distortion while others will have far less.