Suitabilty Of Slr Lenses

[jayenram]

I have a couple of Pentax SLRs (film) (SuperA and ME super) together with a variety of lenses. I am currently considering buying a digital Pentax SLR if the mounting is the same.

My question is: would the old lenses (mostly none automatic) operate correctly with the digital model?

Thanks

[Nordlys]

http://en.wikipedia.org/wiki/Pentax_K_mount

I haven't read the above link yet, but I believe ME super and SuperA share the same K mount with the most up-to-date Pentax SLR models including dSLR. From what I heard, however, the old K mount lenses are more compatible with new SLR bodies (but with a few possible restrictions) than new AF lenses (especially those designed for dSLR) on old Pentax bodies.

However, most kit lenses that comes with entry-level dSLR are quite cheap, that I don't think you want to keep using manual focus lenses on SLR bodies designed for AF, not a big saving for a lot of trouble (focusing not as easy as manual focus lens on manual focus body, I would assume).

Edited September 13, 2006 by Nordlys

[astral]

Unless your lenses have a modern mount compatible with the new digital camera,

or you have a specialist lens where you can manage in manual mode, then you are better starting from scratch.

I was lucky that my Canon EOS lenses are fully compatible with my Canon 10D and all the other Canon digital SLRs

[Tywais]

Unless your lenses have a modern mount compatible with the new digital camera,

or you have a specialist lens where you can manage in manual mode, then you are better starting from scratch.

I was lucky that my Canon EOS lenses are fully compatible with my Canon 10D and all the other Canon digital SLRs

I believe there is an issue also with the effective area, can't remember the term, but if the lens is from a film camera it is meant to cover a 35mm area. Unless the dSLR you have has a 35mm CCD it may not cover it correctly. Example: the lens (dSLR) may show on it 18mm and equivalent to 50mm lens from a film camera. May be wrong about this though.

[eddmun]

Be aware that with some digital SLR cameras, the viewfinder is a lot smaller to compensate for the smaller sensor size (the smaller size can sometimes result in 1.6x magnification of the projected image from the lens) so manual focusing is a LOT harder.

If you are only going to be focusing manually with older lenses it might be worth investing in a more expensive full frame dSLR. I believe this is what tywais is talking about.

Edited September 17, 2006 by eddmun

[Nordlys]

Yes, but it's not so much of a problem using lenses designed for 35mm film SLR on APS-C size sensor dSLR (with 1.6X crop factor) as compared to using lenses designed for dSLR with APS-C size sensor on full-size sensor dSLR, except you don't get the focal length (or view angle) it was designed for.

[Chang_paarp]

The old "K mount" lenses may well fit onto some of the current digital models, but why? (I have a couple of screw mount to K adaptors if you have some realy old lenses.)

The lens requirement for the digital is different, you may even find that the focus plane is in a different place making it almost impossible to get a good focus. You will not get metering in most cases, you will not get auto focus, and if you are not careful when putting it on the body you can damage the contacts.

Current lenses are lighter, sharper and compatable with the current model cameras.

The old lenses are attractive and can be sold to people who like film or expensive door stops. Going on the film sales I see, there are not too many film lovers left.

[jayenram]

I bit the bullet and bought the Pentax *ist DL.

The lense included is a 18 mm - 55 mm (27 - 82, 35 mm equivalent) zoom and appears to be reasonably flexible except in low light conditions (f 3.5 to f 5.6). The old K mount lenses all fit and the 50 mm f 1.7 auto is the easiest to use. Unfortunately, as the focal length of the 35 mm lenses are 1.5 times when used on the digital, what was a useful range for the film format has now become less versatile, i.e.

24 mm becomes 36 mm (only moderately wide)

40 mm becomes 60 mm

50 mm becomes 75 mm

100 mm becomes 150 mm (not as much use as a portrate lense now)

500 mm becomes 750 mm (virtually impossible to use without a tripod)

I've decided to therefore only carry the 50 mm (for low light stuff) as a spare lense whilst keeping the 500 mm back only for specific applications.

[astral]

I use my old 28-70mm as a portrait lens on the digital and find it is ideal.

For you the 50mm will be a good choice.