Originally posted by mr. jef 50s club! I have a little question. I own an A-50 1.7, and as much as i love the images it produces, i'm quite often put of by it's construction, and it's rather nasty aperture ring. I was thinking of maybe seizing an M-50mm if the opportunity presented itself, but would probably only do so if i could find a nicely priced 1.4. Has anyone of you ompared the A 50 1.7 and the M 50 1.4 I know i would prefer the handling of the M, but is it comparable in image quality? On stans-photography.info i read the A 1.7 is better than the M 1.7 but a) is this something one would even notice and b) as before, how does the 1.4 compare to the 1.7.
Oh, and would you suppose the 1.4 is still acceptably focusable on the very spartan focusing screen of the k20D, or do i then also have to invest in a split image focusing screen (that is something i would not really do). Right now, my 50 mm snaps into focus, but i don't know how the shallower depth of field would treat me. Of course, maybe the brighter viewfinder would help...
As noted in the comment above, all of the Pentax 50s are good lenses. Some are definitely better than others, but not that different in actual practice.
Regarding the A 50/1.7 vs. M 50/1.7 vs. the M 50/1.4...The A and M lenses have the same optical formula and should be comparable. The M 50/1.4 is obviously faster, but the f/1.7 is supposed to be sharper at f/2 and f/2.8.
In regards to focus screen...That is truly a thorny issue. The stock focus screen on your K20D shows DOF as it exists at about f/4. This is not good enough for fine manual focus with any lens faster than f/2.8, even with focus assist. I currently use the KatzEye with Optibrite. The split image and microprism help immensely as does the matte donut. Less expensive screens are available on eBay and well as at
focusingscreen.com.
Overall, I am extremely pleased with my aftermarket screen and have no desire to go back to the stock screen. However, I can issue these cautions:
- The aftermarket screens are not as bright as the stock screen, even with the Optibrite treatment
- You will get split image blackout to some degree with slower lenses such as the DA 18-55/3.5-5.6 kit.
- Ditto regarding microprism graininess
- The focus aids may be extremely distracting for close-up and macro photography
Steve