Full Frame E-Mount Lenses??

[William Koenig]

I have been following the news regarding the release of the next NEX lenses. 4 in 2011 and 3 in 2010. Exciting stuff.

I can't find documentation on whether NEX lenses are full frame. I see that the focal lengths on the barrels of the 3 released lenses are for full frame, and don't reflect the crop factor of the NEX3, 5 or VG10.

Is the focal length barrel markings just a DSLR lens convention, or an indication that NEX lenses are full frame.

My thinking is the latter, due to the impending release of the 35mm NXCAM and the NEX7.

Anyone hear anything?

Thanks,

William

[Charlie Webster]

so far all are APS-C.

[R Geoff Baker]

Focal length is focal length -- there is no such thing as 'for full-frame' or otherwise. Assuming you mean that 35mm still camera represents full-frame, there is a 'crop factor' that is applied to any other frame size, but the focal length is a physical reality ... the lens markings are absolutely correct.

Note that many here would argue that the important 35mm frame size is not the one associated with stills photography, but rather that associated with 35mm cinematography -- and so the focal lengths you read of in reference to movie-making and such are relevant to S-35 and the like. Note that the focal length is an absolute, so knowing that a movie was shot with a 30mm lens is not useful if you don't know what format it was shot with ... almost certainly not with a 35mm still camera! Conveniently, APSC is very close to a popular 35mm film format, S-35 -- a 50mm lens on one offers a 26 degree angle of view versus 28 degrees on the other.

The APSC frame size is almost the same as the S-35 frame size. The following tool is very useful for comparing and as an aide in visualizing:
AbelCineTech - Field of View Calculator

Cheers,
GB

[Paul Curtis]

I assume you mean whether the existing NEX lenses have an image circle that would work on a full frame sensor.

Because of the size of them i would guess that they don't, they seem APS-C only looking at the back.

As GB said, focal length is focal length, it doesn't mean that the lens has an image circle that would work on 35mm. Ironically it means that a 16mm lens (which has an effective focal length of 24mm on a NEX) would actually NEVER give you a 16mm angle of view because it will never cover a 35mm sensor size.

hth
paul

[William Koenig]

Thank you for your responses. The Field of View Tool was extremely helpful. I never would have guessed the F3 and 35mm NXCAM sensor is almost identical to an APS-C sensor in size.

So the NEX lenses are compatible to the new NXCAM coming this summer, but will still have a 1.5 crop factor. Same crop factor for Alpha lenses with adaptor.

I will be waiting for its release. Love the fact that it has 24p and XLR.

William

[Charlie Webster]

Originally Posted by R Geoff Baker

there is no such thing as 'for full-frame' or otherwise
Cheers,
GB

Certainly there is. The E-mounts are APS-C lenses, as are many new lenses, and they will not cover a full frame sensor.

On the other hand there are many lenses designed specifically for FF and of course all the legacy lenses designed for 35mm film.

And focal length is focal length, but we all reference "effective" focal length. So actual focal length may differ from effective focal length, which is what matters.

[Paul Curtis]

Originally Posted by Charlie Webster

Certainly there is. The E-mounts are APS-C lenses, as are many new lenses, and they will not cover a full frame sensor.

On the other hand there are many lenses designed specifically for FF and of course all the legacy lenses designed for 35mm film.

And focal length is focal length, but we all reference "effective" focal length. So actual focal length may differ from effective focal length, which is what matters.

I think we're both right. Full frame is generally taken to mean 35mm stills. But obviously every sensor fills the 'frame'. You can get 65mm frames too, so what are they - super sized full frame? :)

I'm awaiting the NXCAM too, the VG10, because of it's 1.8 crop and scaling is no good for me. The F3 looks super nice (and not beyond the budget) but i actually prefer to have an Emount on there and stick a separate recording device on the back. The F3 mount is more expensive to adapt and the camera itself is compressed. I figure for the cost of the F3 body the NXCAM could be configured fully. Maybe. There's a lack of specs to confirm anything yet!

cheers
paul

[R Geoff Baker]

Originally Posted by Charlie Webster

Certainly there is. The E-mounts are APS-C lenses, as are many new lenses, and they will not cover a full frame sensor.

On the other hand there are many lenses designed specifically for FF and of course all the legacy lenses designed for 35mm film.

And focal length is focal length, but we all reference "effective" focal length. So actual focal length may differ from effective focal length, which is what matters.

You've misquoted me, Mr Webster -- and that is poor form ...

What I said was that focal length is focal length -- 16mm is a focal length, and it is only in relationship to the imaging area that one can determine the angle of view. It is usually angle of view that users actually intend to describe when they reference a focal length, and it is only when everyone is using the same imaging area (e.g 35mm still camera) that focal length on it's own describes the angle of view.

The OP hinted that they expected a different 'focal length' marking when in fact what the really wanted (I beleive) was a marking that referenced an angle of view. Your suggestion that 'we all reference "effective" focal length would come as quite a shock to cinematographers that have never used a 35mm stills camera, or photographers like me that used a 2 1/4" square camera as our device -- to suggest that a frame format that has no history of use in film making or video production is the de facto standard seems a stretch to me. If your knowledge is centered on 35mm still work, you may have to learn to convert. If your background was 35mm movies, you'll find that APSC is nearly identical to your experience.

So please, my statement that focal length was not changed by the size of the imaging sensor remains entirely correct ...

Cheers,
GB

[Charlie Webster]

Originally Posted by Paul Curtis

I think we're both right. Full frame is generally taken to mean 35mm stills. But obviously every sensor fills the 'frame'. You can get 65mm frames too, so what are they - super sized full frame? :)

I'm awaiting the NXCAM too, the VG10, because of it's 1.8 crop and scaling is no good for me. The F3 looks super nice (and not beyond the budget) but i actually prefer to have an Emount on there and stick a separate recording device on the back. The F3 mount is more expensive to adapt and the camera itself is compressed. I figure for the cost of the F3 body the NXCAM could be configured fully. Maybe. There's a lack of specs to confirm anything yet!

cheers
paul

yes the 1.8 is a drag

even the 1.5 is less than what we all want.

On the other hand you don't need a sharp lens for video, so the sigmas are just fine, if you need low light.

And we should have a 2.8 wide zoom within a year from somebody. That would be just fine for low light.

all the best,
Charlie