[Rbonn]

I've been researching M42 to K Mount lens transition and I was hoping you guys could fill in some blanks. I read that the introduction of the ME in 1979 brought about the M series of lenses. So my question is, when the MX was introduced in 1975? the only lenses available for it were K series lenses? I"ve also seen that SMC Takumar lenses were M42, yet had the new rubber focus barrel.

Call me anal, but I"m trying to match up some period correct lenses to an S2, an MX and an ME. From what I've learned, the
S2 would have used K series lenses, the MX as well and the MEuse Pentax-M lenses.

Would this be correct? I"m assuming the MX was introduced while the Pentax-M lenses were still be finalized. It's a very interesting period in Pentax history for me, because it was the period when I graduated high school and lusted after a Pentax camera and trips down memory lane is one reason why I"m collecting this period of Pentax history.

Thanks for any input.

[GUB]

Hi
These Resources can probably help you.
Pentax Lenses - Pentax Lens Reviews & Lens Database
Pentax Digital Cameras and Film Cameras - Pentax Camera Reviews and Specifications

I"ve also seen that SMC Takumar lenses were M42, yet had the new rubber focus barrel.

Yes but this was just a cosmetic variation on the older taks. The K series lens was a new designed body but often utilised the earlier optical design.

[GUB]

So my question is, when the MX was introduced in 1975? the only lenses available for it were K series lenses? I"ve also seen that SMC Takumar lenses were M42, yet had the new rubber focus barrel.

I would imagine that the Pentax K mount / m42 adaptor was available from day one of the K mount introduction. Given the fairly basic operation of the first Ks the loss of functions of the m42 lens would not have been too traumatic.

[kypfer]

I would imagine that the Pentax K mount / m42 adaptor was available from day one of the K mount introduction. Given the fairly basic operation of the first Ks the loss of functions of the m42 lens would not have been too traumatic.

Use of the Mount Adaptor K is covered in the KM User Manual, so yes, it would seem to have been available since day one.
Wonder if that makes it the longest-running continually available OEM camera accessory?
The manual also includes a list of available lenses, from 17mm f/4 Fish-eye to 1000mm f/8. They're all entitled SMC Pentax, no apparent mention of "M" or any other suffix.

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Last edited by kypfer; 02-01-2022 at 04:58 AM. Reason: addenda

[Lowell Goudge]

I've been researching M42 to K Mount lens transition and I was hoping you guys could fill in some blanks. I read that the introduction of the ME in 1979 brought about the M series of lenses. So my question is, when the MX was introduced in 1975? the only lenses available for it were K series lenses? I"ve also seen that SMC Takumar lenses were M42, yet had the new rubber focus barrel.

Call me anal, but I"m trying to match up some period correct lenses to an S2, an MX and an ME. From what I've learned, the
S2 would have used K series lenses, the MX as well and the MEuse Pentax-M lenses.

Would this be correct? I"m assuming the MX was introduced while the Pentax-M lenses were still be finalized. It's a very interesting period in Pentax history for me, because it was the period when I graduated high school and lusted after a Pentax camera and trips down memory lane is one reason why I"m collecting this period of Pentax history.

Thanks for any input.

The S2 would use auto Takumar lenses not k mount.

K mount lenses came out in about 1976 with the KX, KM, K1000, K2 and K2DMD.

Your MX and ME super would be able to use CMC Pentax (K) mount, or SMC-M (also K mount) lenses.

The differences between the K and M series cameras is largely the physical size, the transition form a cloth curtain horizontal shutter (KX and KM) to a vertical metal shutter (which was also in the K2 and K2 dmd) and more options for exposure and metering.

[Fogel70]

I believe the M-series lenses were introduced in 1976/77 together with ME and MX. ME Super came in 1979.
But it took a number of years before all M-series lenses were introduced.

[pschlute]

I believe the M-series lenses were introduced in 1976/77 together with ME and MX. ME Super came in 1979.
But it took an number of years before all M-series lenses were introduced.

What he said.

I bought my MX in 1977 and it came with the "kit" lens the M series 50mm 1.7

Do not forget also that the "K" series lenses themselves only date from 1975

[Pål Jensen]

Actually the M-lenses probably came before the M-series cameras. I bought a Pentax K2 in May 1976 and wanted the K 55/1.8 but got the M 50/1.7 instead, cause the former was no longer available.....

[ebahle]

I feel it’s safe to say M series lenses are “period correct” for an MX regardless of release date. They were intended to be compact companions to the amazingly small M bodies

[FozzFoster]

I think it may help clarify to state the K2, KX, KM where released all in the same year 1975, along with the M42 adapter.
The next year, 1976, the ME and MX were released.

[Henrico]

Pentax was rather late introducing the K-mount and K-series of cameras in 1975. Pentax hung on the M42 while Canon and Nikon already used bayonets. Like they now lean on DSLR while the competition choose for MILC, history repeats.... Most K-lenses were optical identical clones of the latest Takumars, some were brand new like the K1.2/50. The K-mount has the same flange distance as the M42, so with the K-mount adapter all M42 lenses could be used what was a real advantage for customer loyalty.

Olympus that days were extremely successful with the miniaturized OM series and that amazing range of beautiful Zuiko lenses. Compared with this stuff the Pentax lines of lenses and cameras were bulky and heavy. Pentax responded very successful with the M-series cameras and M-series lenses in 1977. Most of these lenses were optically brand new designs, some were just compact versions of the K-series (1.4/50 f.i.).

Most M-lenses are mentioned optically not as good as their K-siblings, but for film use these are still great. Aesthetically and mechanically M-lenses are beautiful crafted lenses. Now in the digital era on 36 MP sensors it is clear the miniaturization of the M-lenses, for most the wide angles, suffer a bit in edge and corner performance. On cropped sensors this is no issue, for that purpose wide angle M-lenses are great. The M-era was the most successful era for Pentax I think. After that period more and more plastic was introduced in the camera business with lenses and bodies that were real ugly. Again, Pentax missed the boat adopting decent AF and the market shared declined. The nowadays lines DSLR's and star and limited lenses look beautiful again. From all the brands Pentax deliver best backwards compatibility. That is the reason I still use the newest bodies with almost 50 years old lenses. I hope Pentax can continue this strategy for the next decades.

[Bbsteinle]

Ding ding ding! Henrico for the win!

Basil

[Lord Lucan]

K mount lenses came out in about 1976 with the KX, KM, K1000, K2 and K2DMD.

I believe the M-series lenses were introduced in 1976/77 together with ME and MX. ME Super came in 1979.But it took a number of years before all M-series lenses were introduced.

Being pedantic, only the K2, KX and KM came out in 1975 together with K-series lenses*. It was bad timing because the fashion had already moved to smaller cameras (like Olympus's OMs), so the M-series (M for "mini"?) was introduced only a year later, in 1976, starting with the ME and MX accompanied by reduced size M-series lenses. Production of the KX and KM ceased within 2 years of their introduction.

But Pentax wanted to salvage something from the K-series so in 1976 they re-launched the KM in a cheaper stripped-down form as the K1000, which was immensly successful in the market sector that did not demand the latest tech and fashion (or knew nothing of them anyway). At the same time the K2 received an upgrade aimed at the professional market as the K2-DMD, until replaced by the LX in 1980.

The appearance of these bodies and lenses around the world may have occurred at differing times and some K-series lenses (the more specialised ones, eg 50mm F1.2) were never replaced by M-series equivalents. Otherwise, K-series lenses were meant for K-series bodies, and M-series lenses were meant for M-series bodies. The K1000 was made until 1997, long past its technical "sell-by" date, by which time it was being sold with a much later A-series lens!

One seeming reason why Pentax clung to the screw mount for so long was that they had a idealistic view that lens mounts should be standard across brands. The M42 screw was such a standard. When it was clear that it was no longer tenable, Pentax made their new K bayonet mount design a royalty-free "standard". It was used by a number of other camera makers, generally minor ones including Cosina, Ricoh, and Petri.

* Pentax did not call them "K-series" lenses, that is my term for the lenses produced for the K-series cameras. Pentax simply called them "SMC Pentax" lenses. The "M-series" lenses (again my term) were engraved with "SMC Pentax-M". Both were a similar style with the focussing ring covered in square patten rubber.

[Rbonn]

Being pedantic, only the K2, KX and KM came out in 1975 together with K-series lenses*. It was bad timing because the fashion had already moved to smaller cameras (like Olympus's OMs), so the M-series (M for "mini"?) was introduced only a year later, in 1976, starting with the ME and MX accompanied by reduced size M-series lenses. Production of the KX and KM ceased within 2 years of their introduction.

But Pentax wanted to salvage something from the K-series so in 1976 they re-launched the KM in a cheaper stripped-down form as the K1000, which was immensly successful in the market sector that did not demand the latest tech and fashion (or knew nothing of them anyway). At the same time the K2 received an upgrade aimed at the professional market as the K2-DMD, until replaced by the LX in 1980.

The appearance of these bodies and lenses around the world may have occurred at differing times and some K-series lenses (the more specialised ones, eg 50mm F1.2) were never replaced by M-series equivalents. Otherwise, K-series lenses were meant for K-series bodies, and M-series lenses were meant for M-series bodies. The K1000 was made until 1997, long past its technical "sell-by" date, by which time it was being sold with a much later A-series lens!

One seeming reason why Pentax clung to the screw mount for so long was that they had a idealistic view that lens mounts should be standard across brands. The M42 screw was such a standard. When it was clear that it was no longer tenable, Pentax made their new K bayonet mount design a royalty-free "standard". It was used by a number of other camera makers, generally minor ones including Cosina, Ricoh, and Petri.

* Pentax did not call them "K-series" lenses, that is my term for the lenses produced for the K-series cameras. Pentax simply called them "SMC Pentax" lenses. The "M-series" lenses (again my term) were engraved with "SMC Pentax-M". Both were a similar style with the focussing ring covered in square patten rubber.

thank you so much. this is exactly what I was hoping to learn....

am interesting time in their history. I've read that M series lenses aren't quite as good as K series. what do you think?

---------- Post added 02-02-22 at 06:45 PM ----------

I think it may help clarify to state the K2, KX, KM where released all in the same year 1975, along with the M42 adapter.
The next year, 1976, the ME and MX were released.

in my original post I said S2, but meant K2.....sorry for my error

[Henrico]

Have a look on the lens review pages here, there you can get an impression of how all these old lenses perform.

K-lenses have similar build quality as the late Takumars, very robust. Most K-lenses share similar optics as the Takumars did before. Late K-lenses in fact were M-lenses, like the 24 mm f.i..

M-lenses also are very fine lenses, beautiful proportioned and all metal. Late M-lenses like F2/50 mm were in fact A-lenses without A-setting. Most M-lenses have different optics than the K-series because these had to be compact.

A-lenses introduced the "plastification" era. Although still robust with lots of metal these lenses did not have the build quality as the former ones. Most A-lenses shared the optical formulas of the M-lenses, there were also brand new lenses introduced, most optically very respected.

So for your purposes you can find a lot of fine lenses of all series of that era.