[mmc]

Hello all. First post here. I have a Canon XSi(450D) and would like to get a manual focus lens. I'm looking at either the Voigtlander 20mm f3.5 or the 40mm f2.0. Even though I currently have a Canon body, I would not rule out a future Nikon DLSR, or more likely, a Four Thirds/EVIL camera. One of my factors in choosing a lens will be it's compatibility with different camera bodies/mounts. Even though the two previously mentioned lenses are available in a Canon EF mount, I'm wondering if it would be better to get one in a Nikon mount? I understand that I would lose the Canon metering if I used a Nikon-mount lens with my XSi (via an adapter), but I think the addition of the aperture ring on the Nikon models would be better in the long run.



Question: I've read the [url="5d review http://www.opticallimits.com/canon_eos_ff/504-voigtlander20f35eosff"]Voigtlander 20mm review[/url] on a Canon 5D full-frame body (Nikon-mount lens via an adapter). Will the same Nikon-mount lens (either the 20mm or 40mm, via an adapter) work properly/physically fit on a Canon APS-C body (specifically, the XSi)? I haven't found any reviews yet that covered this body/lens combo.



Nikon-mount lens:

Pro's:

- Works on Canon EF body via adapter, full manual control

- Works on Nikon body, auto metering or full manual control

- Fits Four Thirds/EVIL mounts via adapter (I assume full manual control?)

- Dedicated aperture ring

Con's:

- No auto metering on my current Canon XSi



Canon EF-mount lens:

Pro's:

- Auto metering on Canon body, aperture control through Canon body

- Physically fits Four Thirds/EVIL mounts via adapter

Con's:

- No aperture ring (no manual aperture control on Nikon/Four Thirds/EVIL mount)

- Won't fit on Nikon body



Do I have the above Pro's and Con's correct? If so, I'd buy a Nikon-mount lens and gladly lose auto metering on my XSi for the future compatibility on other bodies. But I am concerned about the physical fit. Any other thoughts? Thanks.



Matt

[edge]

I'm not sure what you mean by auto-metering.

If you use a Nikon mount via an adapter, the Canon XSi will still meter. It will be "stop-down" metering using the ap ring rather than the on-camera dial. You will lose the focus confirm in the viewfinder though. Not a problem if you focus using live view. Also the viewfinder will get dim as you stop down.

[Brightcolours]

[quote name='edge' timestamp='1291096342' post='4588']

I'm not sure what you mean by auto-metering.

If you use a Nikon mount via an adapter, the Canon XSi will still meter. It will be "stop-down" metering using the ap ring rather than the on-camera dial. You will lose the focus confirm in the viewfinder though. Not a problem if you focus using live view. Also the viewfinder will get dim as you stop down.

[/quote]

Depends on the adapter you have. If you have an adapter with so-called "focus confirmation chip" you will not lose focus confirmation, provided you do things in a certain order:



First you open the lens totally, and focus on the scene. Focus confirmation will help you determine focus (usually). Then you close the aperture to whatever aperture you like to use, either in Av-mode or M-mode. Then in Av-mode the camera will decide on the "correct" exposure for you, in M-mode you then set the exposure yourself, with help of the camera's metering.



Av-mode may seem a bit strange, since you can not set the aperture via the camera. But the camera will just always imagine the lens to just be open, and set the shutter speed to the light conditions reaching the metering regardless of the real aperture.

[mmc]

Thanks for the reply's. Everything you've said confirms what I was expecting. Regarding the Nikon mount on a Canon APS-C body, I've since found a Flickr user who mounted a Nikon mount 40mm SL2 onto his XSi with no problems.



[quote name='edge' timestamp='1291096342' post='4588']

I'm not sure what you mean by auto-metering.

[/quote]



I don't either <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/huh.gif' class='bbc_emoticon' alt='' />. It made sense last night when I wrote it. I think I got that from the Camera Quest website that said the SL2 lenses were "Chipped for full meter compatibility".



Matt

[genotypewriter]

[quote name='Matthew' timestamp='1291093982' post='4587']

I have a Canon XSi(450D) and would like to get a manual focus lens.[/quote]

Bad idea... unless you're planning to change the focusing screen to a higher precision one or going to use LV all the time. Just a heads-up <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/wink.gif' class='bbc_emoticon' alt='' />



GTW