SMC M lenses

Yes, plenty of benefits. Autofocus is the obvious one. Newer coatings and optics are generally better at controlling flare, aberrations, give better colour reproduction and micro-contrast.

Some older lenses are of course super-sharp and will outperform cheaper modern ones, particularly cheaper zooms in that department.

Newer models may have better colour or contrast and autofocus but they are less enjoyable to use. For landscape or night photos old lenses are often better because they don't focus beyond infinity.

I have plenty of AF lenses but I love using my M and K and other old manual lenses too, on both film and digital.

Many of the older lenses are on a par with current lenses for the particular characteristics you've mentioned, If you can't find flaws or limitations then I'd stick with what you've got. I tend to use newer lenses for 2 reasons - WR and Autofocus, but if I could focus manually properly I would have more MF lenses. The ones I do use are superb - the A 100/2.8 is incredibly under-rated, as is the A 50/1.4. The K 28/2.0 and 3.5 produce results that I doubt would be bettered by the newer equivalents, and I'm currently struggling with deciding whether I should sell my K 85/1.8 or FA 77/1.8 - the quality is so similar.

Yes the benefits of an upgrade are worthy for some situations, but if you're happy why change

Hard to say. One photographer might have a style that suits wide angles, another might go for a telephoto look. It's what we make out of it that counts.

You can do a lot worse than browse Ebay. You can pick up umpteen manual lenses for peanuts and try them out. That's how I got most of mine and how I learned which were the best - like Takumar 55mm f1.8 (equivalent but better to your M50mm) Helios 44M-7 (stunning - needs a small modification but will take on all comers) Pentacon f3.5 30mm (which is a Meyer Optic 'Lydith') Jupiter 11A 135mm (knocks spots off a Zeiss Sonnar). None of these should cost you more than £20. And finally, the really el-cheapo Miranda 28mm macro (Ex Dixon's Bargain Basement - except it's a little gem). Just put M42 in the search box under Cameras and Photography.

I love the quality that the 'old' lenses give me, and the fun. I broke my 50mm 1.7 'M' last week, which I adored but found a 1.7 'A' on the bay which cost me £35.00 incl postage. Once it was set up I would be pushed to say my £250 plus 2.8 35mm Ltd is giving better results. I fear not. I have to say, though, I am a great beliver in 'catch in focus' with my manual. I am also loving having the feedback the 'A' lenses give.

Best wishes,
Rob

Yes, it was all so wonderful it's hard to understand why any company bothered to design any new lenses after 1979 ...(deliberate sarcasm. ).

This could have been a good opportunity to compare pros and cons of old and new, not just another gushing session for ancient lenses. We all know and love some old lenses, and that commitment may well be the whole reason for using Pentax for some, but a dose of perspective and reality is surely needed!?

I'll give some .... I love going out with the old M75-150 F4 in the City or Croydon and shooting architecture, taking time to focus, green button metering, aperture adjustments on the ring, shutter adjustments for exposure ... Good fun .....but ..... It's utterly useless for family shots, even static portraits (supposedly static ) as the whole palaver of using it plus the focusing/zooming difficulties just screw everything.

So the F35-70 or Tamron 70-300 are the only choices there because of what their more modern designs offer.

It depends on who you are and what you do as well. For the unwary poor quality old lenses can produce low contrast, greeny/purply faded looking shots that need a lot of processing, and frankly the unwary are mostly the ones who can't do the processing anyway. There are some gems of course .... But its about knowing about them .....