Pentax K10D Lens Mount

[sdgmusic]

How do the lenses mount in the pentax K10D? I heard a rumour that the lenses from my old 1970's 35mm SLR (screw mount) would work on the K10D. Is this true?

 

[Don Simon]

The K-mount is the same bayonet mount (the K mount) that Pentax has used since the mid-'70s, so if you have anything from the original K-series onwards (all can be found here http://kmp.bdimitrov.de/) then the lenses will mount straight on the K10d and allow metering. However you have the 42mm screwmount... this will also mount on the K10d and will allow stop-down metering, but will require an adapter. The adapter however is only metal, no optics or electronics required so it is very affordable.

 

[sdgmusic]

Is that adapter available for any DSLR body or just the K10D. I have a '72 Spotmatic II (pentax) and yes the lesnes are of the screwmount variety. I have 4 lenses (that are old but amazing) and I would love to use them on a DSLR is possible, I was originaly looking at the D80, but if the K10D is the only one that will support these lenses that I already own, I would be more inclined to get the pentax. (assuming that I will not use autofocus)

 

[Don Simon]

Actually in addition to any Pentax dSLR you can also use m42 lenses (with the right adapter) on the Canon EF mount, or the Minolta/Sony A-mount. Unfortunately this is not the case with Nikon; because of a spacing difference even with an adapter you would lose infinity focus, plus I think the metering sitation is more complicated. But Canon, Pentax or Sony should work with a basic metal ring adapter and still allow stop-down metering.

 

[sdgmusic]

thanks

Is this ok to do? will my photos suffer? these are good lenses but they're old.

 

[Big Mike]

It's OK to do...but as mentioned, you would need to use 'stop down metering'.

Or you could use a hand held light meter.

 

[sdgmusic]

so basically you're saying it's cool to do but will be more difficult to manage

 

[Big Mike]

It's cool to do...if you have some sweet lenses to use. I don't see much point if you are trying to mount cheap a 30 year old lens.

And yes, it would be more difficult to manage.

 

[Don Simon]

It won't be as convenient to meter stopped-down; generally you would have to compose and focus with the aperture wide-open, before stopping down to meter. Or as Mike says you could just use a handheld meter. Either way the quality of the images won't suffer unless the lens is poor. I tried several old M42 lenses on my dSLR; some were not very good so obviously there was no point using them over a modern zoom, but I used a 50mm f/1.4 before I replaced it with an autofocus one; it hasn't got less sharp over the years and I had some good results with it. Also I still use an old 85mm f/2 with an adapter; yes it's not all that convenient but it costs a lot less than an equivalent modern lens and performs very well. Some people will say that CAD/CAM and various technologies make today's lenses much better... personally I think that at least when it comes to fairly basic primes, a good lens is a good lens. So if your lenses really are good then it could be worth it, but obviously it won't be as convenient as using a modern autofocus lens with a modern autofocus camera. Apart from anything else, most viewfinders and focusing screens now are designed to aid auto rather than manual focus.