Pentax 50mm manual focus...which one?

<p>Which of these Pentax manual focus 50mm lenses is the best, the SMC Pentax 50/1.4, the SMC Pentax-M 50/1.4, or the SMC Pentax-A 50/1.4? Is there any difference in the optics or are they all about the same, and which would you recommend?</p>

<p>I have the M-1.4 and an A-1.7, and in my opinion the A is sharper. But it could just be my copy.</p>

<p>Out of the three lenses you've named, I don't think you could go wrong with any of them.</p>

<p>The 50/1.7 is generally regarded as optically better than any of the 50/1.4 lenses. But it's not as fast.<br>

The formula of the -M may be subtly different from the original SMC "K". But I'd expect the -M and -A to be optically identical. But the -A goes for a lot more due to being much more useful on Pentax cameras with a "crippled" mount, such as all the DSLRs. If you have a crippled-mount camera, the -A is really the one to get.<br>

There's probably more "engineering plastic" and less metal in each successive generation of the lens. If you want a billet of metal, get the original SMC "K" lens.</p>

<p>My favorite K mount standard lens is the original 55/1.8. As far as I can tell the 55/2 is the same as the 55/1.8 but with a different marking. It's also excellent. After that I like the 50/1.7 M. I do not care for the 50/2 M whether made in Japan or elsewhere. The last K mount standard lens I got was a 50/1.7 SMC-F. I use it with my Pentax K-x with excellent results. I must have paid $35-$40 for it a few years ago and it now sells for several hundred. My only K mount 50/1.4 is a Sears (Ricoh) lens. I haven't used it very much but it seems fine. If I could have another 50/1.4 it would be the original SMC Pentax. As far as I know it is the same, optically, as the 50/1.4 SMC M42 lens. </p>

<p>In M42 I had tjhe Super 1,4/50 8 elements, the Super with 7 elements, the S-M-C and the SMC. All in M42 (I repeat). S-M-C is my option. But it yellowed...........<br>

In K mount, the FA 1,2/50.<br>

Digital, the DA 1,4/55.<br>

Rino.</p>

<p> </p>

<p>As for a 50mm F-1.4 I have the Super-Takamura its yellow but as soon as we get some good sun light I will<br>

put it in the sun light and see it that helps reduce the yellowing : But it gives dam good photos and that are sharp :</p>

<p>For a full treatise on all Pentax 50mm 1.4s : See <a href="http://www.luminous-landscape.com/columns/sm-02-11-24.shtml">here</a>.</p>

 

<p>I myself have the SMC-M 50/1.7, and it's good enough for me.</p>

If you also plan to use the lens on a Pentax dSLR then the A is by far the better buy.

<p>I agree with Jeff: if we can expand the choices a little, my sharpest normal lens is the 55 f/2 that came standard on the KX in 1975.</p>

<p>I have the SMC-M 50/1.4, SMC-A 50/1.7, the SMC-M 50/2 and the SMC Takumar 50/1.4 and 1.8 (which might be identical to the original K-mount 1.4 and 1.8 versions).</p>

<p>I found the SMC Tak 1.4 the sharpest wide open, but with lot of coma at the edges. I could find no image quality difference between SMC-M 50/1.4 and SMC-A 50/1.7 wide open or at larger apertures.</p>

<p>If the use of the aperture ring is important to you, you should get the -M or -K versions. The -A lenses have fidgety plasticky aperture rings.</p>

<p>Well I settled on the original SMC 50/1.4 from KEH. The idea that it has the same optics as the SMC Tak 50/1.4 was convincing enough, plus it's a bit larger than the M and A versions and will balance a little better on my KX. I also have the SMC-M 50/1.7 which yields excellent pics as well. The 50/1.4 should arrive by Tuesday, so I'll be sure to road-test it as soon as I get it.</p>