On 02/10/07, ann sanfedele, discombobulated, unleashed: >but seriously, folks - It took me a few beats too long to realize that a >28mm smc Pentax lens on a >35 mm digital camera changes it to a less wide lens -- and, I'm >guessing, the bit of space between the >back of the lens and the camera itself, due to the thickness of the >adaptor also contributes to this.
Your questions have been answered already Ann, but note that the adapter you refer to - yes it does put a tiny bit of space between the back of the lens and the camera - wisely observed. However, this brings the Pentax lens into the correct 'zone' (if you like) for focussing. So it does not contribute in any way in changing the angle of view of the lens. (For angle of view, read 'effective focal length' but this is a disclaimer as I have not been gotten by the focal length bodysnatchers :-) So - your Pentax lens plus adapter on a Canon camera - the distance between back of lens and the sensor is the same as your Pentax lens without adapter on a Pentax camera - back of lens to sensor distance is the same. This is because not all camera manufacturers make their cameras with the same distance between the sensor and the front mounting area for the lens. Hence some conversions to lenses are easier than others. Pentax to Canon being a good example. Canon to Pentax is not a viable proposition - in more ways than one!! HTH -- Cheers, Cotty ___/\__ || (O) | People, Places, Pastiche ||=====| http://www.cottysnaps.com _____________________________ -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
