would the magnification be altered? - also i'd be using an adaptor as its an olympus lens onto a canon 20d digital
thanks Yes, the magnification would be increased by a factor of 1.6, so the lens would act like a 45-168 mm lens. As you know, this is "normal" to mid-telephoto length.
The adapter might mate the lens up, but you may loose the ability to autofocus or even use the meter, so check this out before you buy anything.
The 20D does not have the APS size sensor of approx. 23.6 x 15.8 mm, but a slightly smaller standard Canon size 22.5 x 15.0 mm sensor. This accounts for the slightly different magnification factor. Yes, because of the 1.5x sensor crop it should become about 42-158 on the 20D and most DSLRs with an APS size sensor. I wouldn't bother to be honest.
A number of reasons:
1: The conversion factor, x1.6 for the smaller chip but also some adaptors have a minor conversion factor on top of this (the physical distance between the lens and the camera is extended by the depth of the convertor)
2: Such convertors tend to lose the ability to infinity focus.
3: Apart from losing the autofocus and any automatic metering (you will be able to meter in 'M' mode, it will give you a recommended shutter speed, or do the faux needle match thing) you will also loose aperture control from the camera, you will need to use the manual aperture ring on the lens and meter with the lens stopped down (I.e. manully focus first then stop down)
4: If it's an olympus OM lens it will be designed for film, which can record light from all angles, the light will strike the sensor at all kinds of angles, digital camera work best when the light hits the chip straight on, you will get vingetting and fringing. |
