[techkan]

Hi,

I saw the following 50mm Prime lenses at ebay -

1. SMC PENTAX -A 1.2 50 mm
2. SMC PENTAX-M 1.2 50mm
3. SMC PENTAX -M 1.7 50mm

Which one should I opt for ? Prices are more or less the same.


Regards,
Kans

[Sagitta]

The A. Auto aperture is a huge bonus to have.

[Chaos_Realm]

SMC PENTAX-M 1.2 50mm

This doesn't exist, I think it would be a M 50 F/2 There is only A 50 F1.2 & K 50 F1.2.

But The A 50 F1.2 is a fantastic lens but normally a few hundred dollars. The 'K' & 'M' versions of 50mm F1.7 lenses tend to be around $50-100 the 50mm F1.4 around $70-130 the "a" versions a bit more

[VictorDA]

SMC PENTAX -A 1.2 50 mm
SMC PENTAX-M 1.2 50mm
SMC PENTAX -M 1.7 50mm

Hi, I believe you mean:
SMC PENTAX -A 1:2 50 mm
SMC PENTAX-M 1:2 50mm
SMC PENTAX -M 1:1.7 50mm
In which case I would go for the latter (the 1.7) which is the largest aperture and also the best quality. But be aware that it is a full manual lens. If you want auto aperture (being able to use Av and Tv modes) you can go with the A 1:2, sacrificing a little light and image quality for convenience.
None of these lenses should go for much more than USD 50 / EUR 50.
Have fun!

PS: if one of these lenses is indeed a "1:1.2" and is under USD 100 --> GET IT!!!

[techkan]

Sorry for the Typo. These are -

SMC PENTAX -A 1:2 50 mm
SMC PENTAX-M 1:2 50mm
SMC PENTAX -M 1:1.7 50mm

And cost is around USD 45. Another lens which I found is SMC Pentax M 1:1.4 50 mm costing USD 60

[VictorDA]

SMC Pentax M 1:1.4 50 mm costing USD 60

This is a sweet deal too in my opinion. Between the A 1:2, the M 1:7 or the M 1:1.4 it's really a matter of personal preference... Though personally I know I would go for the 1.4.
When buying one of these old lenses, first thing to do is to check it for any defects (the glass should be clean, the rings should turn freely and smoothly, the blades should be snappy when pulling the small lever on the mount). But don't worry, these are really hard to break and most of the time there are no bad surprises!

[NaClH2O]

I'd get the A 1:2. Here's why:
1) Auto aperture is a LOT more convenient
2) Lens meters more consistantly on all Pentax bodies but esp K10D, K20D K-x and K-r. Those 4 bodies especially have difficulty metering with K and M lenses. Curiously the oldest Pentax digital bodies the istD and the istDS don't seem to have as much trouble. The K-7 and the K-5 have some minor inconsistancy but no where near the severity of the K10 etc mentioned above.
3) P-TTL flashes also have highly inconsistant metering issues with full manual lenses.

NaCl(all other things being equal get the A)H2O

[northcoastgreg]

Another lens which I found is SMC Pentax M 1:1.4 50 mm costing USD 60

For $60 that's a pretty good deal. That's the one I would get. The 50/1.4 has better bokeh than the 50/1.7, and is a significantly better lens than the f2 50s.

I own an M 50/2 and an M 50/1.7. The M 50/2 has the same optical build as the A 50/2, so the two lenses are very similar. The M 50/1.7 is flat out superior: far better contrast, richer, more vibrant colors, better all around image quality. For that reason I would take the M 50/1.7 over A 50/2; I would not sacrifice IQ for the greater convenience of A setting.

[techkan]

Thanks for the guidance. I am buying both M 50/1.7 and M 50/1.4