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08-06-2010, 06:47 AM   #16
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Must we keep fighting the M42 adapter wars? Basically, 3 kinds of adapters exist:

1) Official Pentax adapter - safe, expensive, tedious, OK when one has few M42 lenses. I own one.
2) Cheap clones of (1), which are fine AFTER THE SPRING AND SCREW ARE REMOVED. Good when one has many M42 lenses; just leave the adapter tight on the lens. I own a couple dozen.
3) Cheap, safe flanged adapters. Infinity focus is lost. Good for old lenses that focus past infinity, or macro or close-up applications where you don't care about infinity. I own several.

@OP,
It seems the manual lenses you're using now aren't M42 screwmounts, so don't worry about adapters until LBA (lens-buying addiction) sets in. Then you're doomed. Meanwhile, K- and M- and A-type manual lenses all have the PK bayonet mount, and if you stick to those, adapters aren't needed.

And I'll ditto the recommendation about using CIF (Catch-In-Focus), the unwealthy person's autofocus. It's a *snap* to use. Combined with Continuous Shooting, you can do wondrous things.

08-06-2010, 09:17 AM   #17
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Not sure I have a lot to add to what's been said, other than that I shoot mostly (~70%) old glass on my K-7. I love my Ltds. but the experience of shooting manually along with the quality of the vintage glass (color, contrast, etc.) really makes it a pleasure.

If you have the means the A lenses are probably a better bet. it's great to be able to shoot in Av and TAv and just concentrate on focusing. The green button isn't that big of a hassle when shooting Ks and Ms (and it's a lot better on the K-7 than on my K10D, where it's positioned too close to the AF button) but, all things being equal, it's more convenient.

Not that this should stop you from picking up a sweet K or M if it comes your way. I know I <heart> my K 135 F2.5.
08-06-2010, 11:25 PM   #18
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Michaelina2:

Thanks for the tip regarding catch-in focus. I must admit I've been aware that it exists BUT I've always been deterred by the fact that, when I leave the camera (K-m/K2000) in autofocus mode with a manual lens, the focus indication does NOT appear to be necessarily consistent with accurate focus.

It seems to be accurate with, for example, some 50mm lenses and (of all things!) my Tak (Bayonet) 135mm f2.5, but results in GROSS front-focus with the M 135mm f3.5. Also, 28mm lenses give focus indication over a very wide band of focus distances.

However, I shall follow your advice and experiment with catch-in focus. In fact, when I get an opportunity, I'll report back on my findings!

Regarding getting carried away, yes I agree. But it does depend on how you view your hobby. If you simply want to take great photos in a wide range of situations then it's probably best in the long run to identify a few great (modern, autofocus) lenses, and acquire them, over time if necessary.

But some people are slightly different - for them part of the fascination is in the scientific and engineering aspects of photography, and this means an interest in the hardware itself, as opposed to the hardware just being a means to an end. Add in the "collector" factor and you end up with the underlying cause of LBA.

I'm certainly in that category, I enjoy acquiring cheap (but good quality and/or interesting) lenses and using/comparing them. But, I do agree that, overall, it isn't necessarily a particularly cost-effective thing.

RioRico:

Sorry if I've stirred things up again regarding "adapter-wars" (I don't want to spoil the constructive tone of this thread), but I was thinking that for the OP's situation the proper adapter would be the most appropriate.

I have to admit, though, that the bungled "Chinese-copy" adapters offend my engineer's sensibilities. (I DO like the flange-type though - they're simple, cheap, a joy to use in the right circumstances. Almost worth adjusting the infinity end-stop on the lens for.)
08-07-2010, 02:02 AM   #19
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Michaelina2 and RioRico, on the subject of catch-in focus and the intricacies of the AF system, I think we're all aware that the camera takes into account the lens that's currently mounted, and fine-tunes the focus-point accordingly. But here's an interesting little aside:

I recently bought a bargain-priced DA 50-200 WR, and was testing it for sharpness. I was intrigued to discover that it would re-focus when I changed from wide-open to f11. What's more, by turning off AF when changing to f11, I was able to compare the images for f11 shots with and without re-focus; the ones WITH re-focus were (slightly!) sharper than those without. (Tests performed using a tripod, SR off.)

This indicates to me that Pentax are aware that focus changes with aperture for the DA 50-200, and changes sufficiently for re-focus to be desirable.

I'm sure that this is a feature of spherical aberration compensation in the lens, so it probably affects most lenses. It does go to show that accurate focus can be a rather elusive commodity! (Stopped-down Live View for manual lenses, anybody?)

08-07-2010, 08:00 AM   #20
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You are welcome and...

QuoteOriginally posted by m42man Quote

Thanks for the tip regarding catch-in focus...

Regarding getting carried away, yes I agree....
...I understand.

Let me expand on the suggestion regarding anchoring a "collection" with the FA 31... My point is that it really helps me to have an excellent reference lens to use when its time to determine if the new candiate deserves tenure in the collection. Plus, the anchor gives me a solid fall back position should it not pan out. Frankly, it does not matter if itís the FA 31; it could be anything that fits one's preferred subjects. Currently, I use the D FA 100/2.8 MACRO as my reference lens since I like to photograph butterflies encountered while walking my dog. It rises above awesome (on a low to high scale of 1-10, it's a 15+, in my book), but that's another story. Fortunately, we have many good lens choices available from which to choose (I like the DA 35/2.8 MACRO, and DA 40 Limited, too).

In a nutshell... If the goal is excellence, I found it helps to have excellence as a point of reference. YMMV

Cheers and enjoy the season...
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