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07-28-2009, 10:09 AM   #16
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QuoteOriginally posted by Igilligan Quote
I look forward to your eastern bloc version of this test... The CZ Jena - The Jupiter and the Tair...
I will probably get bitten by the collector bug again after I sell off some of these.

QuoteOriginally posted by Marc Sabatella Quote
Thanks for dong this - you do such a nice job with these! BTW, I don't know if there are multiple Sears 135/2.8, but I had one, and it was pretty clearly worse than the M135/3.5 in all respects that I tested, but I can't sa I was anywhere near as thorough as you! The JC Penney 135/2.8, on the other hand, looks pretty good to me.
I had a couple of Sears 135/2.8 lenses that were labeled the same, even had the same catalog numbers, but one was a half-inch shorter than the other. Weird.

QuoteOriginally posted by stevebrot Quote
My Vivitar 135/2.8 (Komine) has an eight-bladed iris. Was there a miscount or have we discovered yet another variant?
The one in this test does have six blades, with s/n 28920974 and the newer rubber focus grip. I looked at my auction photos, and discovered s/n 28526017 with eight blades. S/n 28720232 and s/n 28802693 had six. I never noticed the difference before. I know there is a close-focus version - I think Hinman had one.

QuoteOriginally posted by Lowell Goudge Quote
Couple of comments.
Lens hoods.
the SMC 132F2.5 has a snap on hood that is shared with other pentax primes using the 58mm Filter. The Bayonette Takumar, and I believe later 135 F2.5 super taks have a metal screw on hood.
I don't have the 58mm snap-in hood; I kept the screw-in hood from a Super-Takumar instead. I didn't use it in the test because I only remembered it halfway through. The Takumar Bayonet has a slide-out hood. In the samples I have owned, this hood sometimes doubles as a damage absorber.

QuoteOriginally posted by Lowell Goudge Quote
with respect to all the lenses, can you give an indication of exposure accuracy of the lens. I.E. check exposure at F8, and then run through all the aperture stops setting shutter speed accordingly for same exposure, and measure grey scale. Some of the lenses have a tendancy to drift upward in exposure at the smallest F stops.

It would also be interesting to know how the metering on what ever cameras you have worked.

see below for the SMC 132F2.5

note also the umarked stop is F2.8 based on exposure testing I did.
I almost can do this from the photos I used for the sharpness tests, but I haven't attempted it. I use the same method for exposure but the wrong target. The bricks probably vary too much for a good test. If you look at the composite image for center sharpness, it looks initially like a couple of lenses are really consistent, but they are also lower-contrast ones.

I am not good enough at metering with the *ist DS and Katzeye screen to make any meaningful comments about it. I can always find a reason for inconsistencies that I see. Also, I use center-weighted all the time to try to smooth out differences in my varied lens types.

07-28-2009, 10:23 AM   #17
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For other readers, My comment, was about metering tests

QuoteOriginally posted by Just1MoreDave Quote
I almost can do this from the photos I used for the sharpness tests, but I haven't attempted it. I use the same method for exposure but the wrong target. The bricks probably vary too much for a good test. If you look at the composite image for center sharpness, it looks initially like a couple of lenses are really consistent, but they are also lower-contrast ones.

I am not good enough at metering with the *ist DS and Katzeye screen to make any meaningful comments about it. I can always find a reason for inconsistencies that I see. Also, I use center-weighted all the time to try to smooth out differences in my varied lens types.
Yeah, I hear you, metering on the K10D, bad as it was, got worse (especially spot) with my JinFinance diagonal split image.
07-28-2009, 10:37 AM   #18
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QuoteOriginally posted by Class A Quote
I've seen one shot (I think from Marc) that seemed to defy the lack of resolution of the M135/3.5 but all others confirmed my impression of it as an underperformer.
My theory is that it depends on how you are using it. When I'm using this lens wide open, it is generally because I am dealing with low light and am striving to get as fast a shutter speed as possible. And in those cases, I'm also dealing with high ISO, and the corresponding noise robs me of a lot of detail (whether I leave the noise in or try to reduce it). Plus of course in concert photography - which is the situation where this comes up the most for me - I'm also dealing with moving subjects, and shooting handheld. This also tends to put a cap on just how sharp an image on can possibly expect to get. All that tends to blur the distinction between *really* sharp lenses and only *kind of* sharp ones (although truly bad lenses will probably still look bad). I think the M135/3.5 is capable of performing about as well as the constraints of concert photography allow, so the advantages of a better 135 would be largely lost on me.

That's all just a theory, mind you, but it does make sense to me, and fits in nicely with my experiences using this lens in other contexts. It is not especially impressive to me (compared to my DA50-200, say) in situations where one might reasonably be hoping for a higher degree of technical excellence than is the norm for concert photography. In good light at ISO 100 with a nice fast shutter speed - situations where the best lens can *really* excel - I'm rarely as knocked out by the performance of the M135/3.5. Wide open portraits in particular tend to be kind of disappointing. Although when I look at Dave's images, I see the M135/3.5 doing quite well at f/11.

Everything I've said here also applies to my M100/2.8, BTW.

QuoteQuote:
Perhaps the one good shot was very well sharpened and took on sharpening really well?
I can't be sure which one you had in mind, or if it really was indeed one of mine (although I doubt Marc Langille uses the M135/3.5, so I assume you didn't mean him!). But FWIW, I do recall one image in particular I've posted that impressed *me* (and a few other people), and that was this one:



This image comes to mind in part because I know I had also posted a link to a full sized image:

http://marcsabatella.zenfolio.com/img/v7/p711839810.jpg

If you really look at the full size version, I think it illustrates what I'm saying pretty well. It isn't *really* particularly sharp by the standards of outdoor / ISO 100 photography. But for a concert shot, it's not bad at all. The lens seems to be performing up to the limits of what the K200D can resolve at the equivalent of ISO 3200 and what can reasonably be expected shooting a moving subject handheld at 1/30". See her ear stud (the one above the hanging earring) in particular. For what is basically just a handful of specular highlights, it's kind of cool to be able to make out as much as you can given the circumstance and the fact that it is just a few pixels in size. But again, had I tried this same shot under more favorable conditions, I suspect the sharpness of the lens would have been a limiting factor.

Last edited by Marc Sabatella; 07-28-2009 at 10:46 AM.
07-28-2009, 10:47 AM   #19
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QuoteOriginally posted by Marc Sabatella Quote
My theory is that it depends on how you are using it. When I'm using this lens wide open, it is generally because I am dealing with low light and am striving to get as fast a shutter speed as possible. And in those cases, I'm also dealing with high ISO, and the corresponding noise robs me of a lot of detail (whether I leave the noise in or try to reduce it). Plus of course in concert photography - which is the situation I am most often using this lens wide open - we're also dealing with moving subjects. Which also tends to put a cap on just how sharp an image on can possibly expect to get. All this tends to blur the distinction between *really* sharp lenses and only *kind of* sharp ones (although truly bad lenses will probably still look bad). I think the M135/3.5 is capable of performing about as well as the constraints of concert photography allow, so the advantages of a better 135 would be largely lost on me.
marc

the only comment I can make on this argument, is of course, wouldn't you like the 1 stop advantage of the K135F2.5, which from my experience qualifies as really sharp wide open, along with a brighter viewfinder?

Although on the down side, the shallow DOF of the F2.5 might give you focusing problems, and apparent loss of sharpness just because less is in focus.

07-28-2009, 11:24 AM   #20
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I keep changing my opinion about how usable a 135/2.5 really is at f2.5. In really low light, the brighter viewfinder helps a lot to get the correct focus. But you have to be 20-25 feet away from a person to get their head within the DOF. I have taken some pretty bad portraits before learning how the lens should work.
07-28-2009, 02:24 PM   #21
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QuoteOriginally posted by Lowell Goudge Quote
marc

the only comment I can make on this argument, is of course, wouldn't you like the 1 stop advantage of the K135F2.5, which from my experience qualifies as really sharp wide open, along with a brighter viewfinder?

Although on the down side, the shallow DOF of the F2.5 might give you focusing problems, and apparent loss of sharpness just because less is in focus.
Yes to everything you said. Add in the difference in size/weight, and I'm not looking to make a change. I also have the DA70/2.4 and M100/2.8 available, so it's not like I'm limited to only shooting at f/3.5, and I think both of those lenses are sharper wide open than the M135/3.5, too.
07-28-2009, 03:54 PM   #22
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QuoteOriginally posted by Just1MoreDave Quote
Here's a quick one.
Ah, the M135/3.5 is such a beauty and the built-in lens hood is sweet. If only it rocked optically.

QuoteOriginally posted by Marc Sabatella Quote
I think the M135/3.5 is capable of performing about as well as the constraints of concert photography allow...
Everything you said sounds totally plausible to me. Except that, perhaps, the very nice shot of the lady would have come out even a tad better with a better lens. Maybe not.

QuoteOriginally posted by Marc Sabatella Quote
I can't be sure which one you had in mind, or if it really was indeed one of mine ...
I meant you and IIRC it was a nature shot (dragonfly?). But it may have been someone else's. I tried to find it, but no had luck.
07-28-2009, 06:37 PM   #23
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No dragonflies from me, but I have posted a few other shots, including of insects, with the M135/3.5 combined with the Raynox 150 closeup lens, and those were indeed pretty sharp. As they should be, having be shot pretty far stopped down for DOF purposes.

For instance, there was this one:



07-28-2009, 11:41 PM   #24
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QuoteOriginally posted by Marc Sabatella Quote
For instance, there was this one:
Yep, that's the one. Thanks for digging it out.

That isn't a dragonfly?

The high f-ratio helps me to understand the image and maybe there is also some useful interaction between the Raynox and the M135/3.5?
07-28-2009, 11:54 PM   #25
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Pentax SMC K 135mm f/2.5 with K20D and GX-10 performance..

https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/47876-legendar...rformance.html
07-29-2009, 08:58 PM   #26
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I must mention that I own a Takumar bayonet 135 f2,8 and it performs a lot better than I would have expected, and better than your 2,5 I would guess. It seems there is HUGE sample variation with these lenses. My personnal lens cannot compare in sharpness to my best lenses, but it's really not that bad. Colours are beautiful, rich and very film-like. I have taken some of my best portraits with that lens. I think evaluating such a lens should also take into account the use it will be put to.

In any case, thanks for the tests, they were very interesting!
07-30-2009, 09:18 AM   #27
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QuoteOriginally posted by stevebrot Quote
..I am a little curious...what happened with the Viv 135/2.8 on the distance test?
Oh, I forgot about that. Just a focus error. I left the picture in for an idea of colors and contrast. It does actually focus at a distance. I could prove that today, but for some reason we are getting Pacific Northwest weather this week while you get our weather.
07-30-2009, 09:38 AM   #28
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QuoteOriginally posted by bdery Quote
I must mention that I own a Takumar bayonet 135 f2,8 and it performs a lot better than I would have expected, and better than your 2,5 I would guess. It seems there is HUGE sample variation with these lenses. My personnal lens cannot compare in sharpness to my best lenses, but it's really not that bad. Colours are beautiful, rich and very film-like. I have taken some of my best portraits with that lens. I think evaluating such a lens should also take into account the use it will be put to.

In any case, thanks for the tests, they were very interesting!
I have a theory about variation. The f2.5 is vulnerable to getting oily aperture blades, and that oil might also get on the lens surfaces. I did clean this lens before testing to make sure that wasn't a problem here. Even if my results were perfect, they only apply 100% to this one lens.

Your f2.8 lens might be a 5 element design like the Vivitar/Komine or Sears. (The f2.5 uses four elements.)
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