[Jonathan Mac]

That's for sure. I still use mine regularly and it's nice to see other's that do the same.

Collecting K series lenses is a slow and often expensive hobby, though I'm slowly accumulating a modest collection. They're much rarer than Taks or M series and often regarded as the optical pinnacle of old Pentax manual lenses. Their larger size makes them more comfortable for me to use. I like the K series of film cameras and I think the matching lenses look and feel better to use on them.

[SteveM]

Just out for a walk today.....K3 and a K28/2.0

[ultraviolet]

Finally I got some time to get out to try the SMC Pentax 1:2.8/30mm in the cold.

[utak]

Collecting K series lenses is a slow and often expensive hobby, though I'm slowly accumulating a modest collection

Me too. And here's my best value for money find to date: the K 135/3.5. I got mine in excellent condition for $50 plus postage in a contested e-bay auction. Its sharp, produces lovely colours and is an interesting walk around lens, especially for longer-distance candid street shots. I tend to use it to around f5.6/f8, so I don't miss the faster and more expensive K 135/2.5.

I've boosted the colours and contrast on this photo for fun, and the original was so well rendered it coped well with the additional processing.

[Ray-uk]

UtraViolet ... fantastic pics, looks like 30/2.8 is another one to put on my wanted list.

Utak .... nice to see the 135/3.5 performing well, a greatly underated lens in my opinion. Mine doesn't get as much use as it should. Far better than the M version.

[SteveM]

Nice set UltraViolet and Utak! I've always enjoyed the "contrasty" colours the K mounts produce.

[Douglas_of_Sweden]

Collecting K series lenses is a slow and often expensive hobby, though I'm slowly accumulating a modest collection. They're much rarer than Taks or M series and often regarded as the optical pinnacle of old Pentax manual lenses. Their larger size makes them more comfortable for me to use. I like the K series of film cameras and I think the matching lenses look and feel better to use on them.

I think it varies a lot from market to market. Here in Sweden the K serie is more common than the Takumars and about as common as the M and A series.

I don't realy understand how you reason to make them the "optical pinnacle". The majority of the K serie lenses uses optical formulas identical to their m42 counterparts, they just changed the exterior and the mount.
I'd admit that the M serie for some focal lengths were not as good optical because they optimised for small size (in the fight with Olympus and others on whom made the most compact SLR system).
The most complete lens program, as well as the largest number of extreme high quality lenses were the A generation. Not even the fully expanded FA serie could match that. But with the A serie Pentax did for the first time cut the costs on some of the mass produced cheaper normal zoomes and other common lenses (such as the small plastic part in the aperture ring that wear out inside the A50/2 and A50/1.7, but not in the A50/1.4 and A50/1.2). Lots of people have these mass produced lenses, but much fewer have tried the A* lenses...so this has somewhat colloured peoples ideas about the A serie. But if we have to select the "optical pinnacle" in terms of a generation of Pentax lenses, it must clearly be the A generation. That doesn't mean that I don't love my K generation lenses. But if you seriously consider them the optical pinnacle, you should let the SMC Takumars share that position, since they are with few exceptions the same lenses.

[SteveM]

I don't realy understand how you reason to make them the "optical pinnacle". The majority of the K serie lenses uses optical formulas identical to their m42 counterparts, they just changed the exterior and the mount.

I'd agree with your comments on some of the A* series lenses, but each lens series has a few gems.

The optical formula of K85/1.8 was dropped once the M series was created. I have the same in SMC Takumar, but prefer the Ks as I can focus in full light regardless of which aperture I am using.

The K28/2.0 is another lens I use constantly. The lens formula is not available in another lens series, such as the M and A 28/2.0 variants.

[baro-nite]

The lens formula is not available in another lens series, such as the M and A 28/2.0 variants.

Other K-series favorites not available in later versions are the 28/3.5, 30/2.8, and 35/3.5.

[Douglas_of_Sweden]

But what you have to understand there is that the M serie never entirely replaced the K serie at once. Many K serie lenses were not replaced but remained available until the A serie came. For instance, the replaced the K135/3.5 with the considerably better M135/3.5, but they kept the faster K135/2.5 until the A135/2.8 and A*135/1.8 replaced both. There was never any 24mm in the M serie (instead the K24/3.5, which was the same formula as the SMC-Tak 24/3.5, had been replaced a few years earlier with the K24/2.8). The M serie was never a complete lens program in the same way as the K and A generations. I have price lists from these years and they show both series for sale at the same time. When the A serie came, much more lenses were replaced at the same time. A few M lenses remained for sale for a while, but probably only until they run out of stock.

[utak]

nice to see the 135/3.5 performing well, a greatly underated lens in my opinion. Mine doesn't get as much use as it should. Far better than the M version.

the replaced the K135/3.5 with the considerably better M135/3.5

These kinds of different views are what makes this forum so enjoyable!

[Jonathan Mac]

I'm surprised the K series are so common in Sweden, I assumed the distribution would be similar to that of the UK.

What I meant by "pinnacle" was that the Ks often have the highly regarded optics of the Taks with the convenience of a K-mount. After that the M series lost optical quality in many cases and the A series lost the all-metal build quality. The K series was where IQ met BQ in a bayonet mount, even if the birth of a full range of * lenses in the A series brought superior IQ and speed.

[SteveM]

But what you have to understand there is that the M serie never entirely replaced the K serie at once. Many K serie lenses were not replaced but remained available until the A serie came. For instance, the replaced the K135/3.5 with the considerably better M135/3.5, but they kept the faster K135/2.5 until the A135/2.8 and A*135/1.8 replaced both. There was never any 24mm in the M serie (instead the K24/3.5, which was the same formula as the SMC-Tak 24/3.5, had been replaced a few years earlier with the K24/2.8). The M serie was never a complete lens program in the same way as the K and A generations. I have price lists from these years and they show both series for sale at the same time. When the A serie came, much more lenses were replaced at the same time. A few M lenses remained for sale for a while, but probably only until they run out of stock.

Agreed....I don't think the M series was intended to replace the K series. The M series was intended to be smaller, from camera bodies to lenses. Some optical formulas could not satisfy the "smaller....lighter" goal of the series. This is why the K85/1.8 was reproduced as a M85/2.0. I don't think the M85 was ever intended to be a better performer.....just smaller.

I think we saw an increase in optical performance from the A series as the designers were able to increase size as needed. However, we start seeing increased use of plastic, and a different type of quality in the build.

[Douglas_of_Sweden]

Agreed....I don't think the M series was intended to replace the K series. The M series was intended to be smaller, from camera bodies to lenses. Some optical formulas could not satisfy the "smaller....lighter" goal of the series. This is why the K85/1.8 was reproduced as a M85/2.0. I don't think the M85 was ever intended to be a better performer.....just smaller.

I think we saw an increase in optical performance from the A series as the designers were able to increase size as needed. However, we start seeing increased use of plastic, and a different type of quality in the build.

I can guarantie you that there is no plastic in the A*85 and A*135. Nor do I think there is in the majority of the *-less A lenses. The exception is the simpler normal zooms, the kit-50mm lenses and a few others sold in large numbers. The rest of the A lenses I have is as much metal as the K and M lenses.

The M85/2 was actually not a new invention. As much as the K85/1.8 was a modification of the SMC-Tak 85/1.8, the M85/2 is an external redesign of the Sup-Tak 85/1.9. At least the optical formula is so close that I can not see any difference. It was a more compact design than the 85/1.8 from the beginning, and taking it down to f2 made it even more compact, and able to match the 85/2-lens Olympus offered.

[SteveM]

I can guarantie you that there is no plastic in the A*85 and A*135. Nor do I think there is in the majority of the *-less A lenses. The exception is the simpler normal zooms, the kit-50mm lenses and a few others sold in large numbers. The rest of the A lenses I have is as much metal as the K and M lenses.

I have the A* 200/4 Macro, 300/2.8, 600/5.6 and 1200/8 and love them. I have owned a number of standard A series lenses such as the 50/1.4 and 20/2.8. I agree the build quality is terrific, but for me, the build quality of non-star standard lenses in that line are not the same as the K line.

The M85/2 was actually not a new invention. As much as the K85/1.8 was a modification of the SMC-Tak 85/1.8, the M85/2 is an external redesign of the Sup-Tak 85/1.9. At least the optical formula is so close that I can not see any difference. It was a more compact design than the 85/1.8 from the beginning, and taking it down to f2 made it even more compact, and able to match the 85/2-lens Olympus offered.

It's been such a long time since I've had the 85/1.9 that perhaps if I was to use the 1.8 and 1.9 side by side I'd have a better opinion of the 1.9, but I don't think so. I doubt the 85/2.0 made a correction.