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Old May 24, 2011, 5:39 AM   #11
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Very interesting discussion!

Personal budget keeps me at the cheaper glass level - but have been very pleased with some old and bargain-condition lenses. Particularly the A 35-105 - was very cheap, but has great color and sharpness. Also some old used extension tubes pair very well with A 50 F1.4 for wildflowers. And have been surprised at the sharpness of a (consumer grade) Sigma 70-300 when used at 300mm in the "semi-macro" range.

Would be very pleased to someday own the DA 12-24 for landscapes, but will keep the 16-45 for now... (it still works even after dropping it on the rocks, and it is paid for.)

Manual focus isn't always easy with these old eyes, but worth it for the (inexpensive) results...
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Old May 26, 2011, 6:21 PM   #12
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Given my current photographic tastes I think I have the wide end well taken care of. The DA 14, DA 10-17 and FA 35 takes me from wide to normal. Beyond that the FA 50 starts the telephoto end. The DA 70 Limited looks like a candidate for the next purchase (it seems to check all of the right boxes for me) and although it is far from perfect the DA 55-300mm seems to be a good long lens compromise, it is much sharper than my FA-J 75-300 and not nearly as expensive as a DA* 300 or DA* 60-250.

I still have the WR kit lenses for harsh conditions, they have given some very good results so they will stay as the travel pair as well (just two lenses to cover 18-200 while travelling).

I would really like the DA* telephotos but the combination of high cost and a mild hesitation about SDM make them less likely (of them all the DA* 50-135 is probably the one I would more likely get, the lower relative cost and great flexibility of this lens make it very desirable).
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FA 35mm f2, FA 50 f1.4, FA 28-70mm f4, FA 28-80mm f3.5-5.6, F 50mm f1.7, Tamron SP 70-200mm f2.8 Di, DA 10-17 f3.5-4.5, DA 14 f2.8, DA 16-45mm f4, DA 18-55mm f3.5-5.6 WR, DA 50-200mm f4-5.6 WR, AF-540FGZ

Olympus E-P2, E-P5, OM-D E-M1: 9mm to 150mm lenses

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Old May 26, 2011, 9:18 PM   #13
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Ira, I'm not familiar with the concerns about SDM lenses. Can you tell me what the issues are, or, if it has already been discussed, provide a link ?
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Old May 26, 2011, 10:28 PM   #14
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I was going through some of my shots at Red Rock and can say that the DAL 35 f2.4 is a little gem. Is yours ever sharp, and excellent bokeh, especially when you consider how little they charge for it. It's possible that one could have put my desire for the FA 31 on the backburner for a while, if I had bought it instead of the DA 35 macro. But now that I have the FA 31 I'd probably be looking to sell the little DAL, while I'm still on the fence about the macro - its nice to have its close focusing ability in a relatively small and light (compared to the Viv) package.

Some of the early SDM lenses have had the AF motor fail. The DA*16-50 seems to be the lens most often talked about with failures on other pentax forums. The way some people talk on other boards, all SDM lenses will fail, but I'm not sure I buy that. I have one of the first DA*50-135 lenses sold in Southern California and its been working fine all along. There is some speculation that letting the lens sit for a long time is a contributing factor (which could be a reason mine continues to work - I use it constantly), but no one really knows. Also, reports of such failures seems to be mostly older lenses, like mine, not many new ones have failed. While I've read about it for a long time, it didn't stop me buying the DA*200 and DA*300.

I'm still very interested in the DA*16-50 as I really want something in that range that's weather sealed. If I do get one (and I most likely will at some point) I'll make sure I'll buy an extra extended warranty, just to be on the safe side. In some ways I've been waiting to see if Sigma might bring out their 17-50 f2.8 out in a weather sealed version because then I'd have a very tough time making up my mind. Luckily, the coffers are bare at the moment, so I'll think about it some more until next year.

The DA 55-300 really is a nice consumer lens, especially if you take it on it's own merits. Even though I have other choices, I won't sell mine - it's Dan's favorite lens and one I'll often use when I don't want to drag along a big camera bag. I still am happy I bought one. But there's just something about the DA*300 that is wonderful. Occasionally I'll see a 3D effect that the DA 55-300 isn't capable of. It doesn't happen all the time, I'm not a good enough photographer to do that, but every so often everything comes together correctly and the results can be magical.
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Old May 26, 2011, 10:49 PM   #15
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I would not let the rumours of early SDM failures stop me from purchasing a DA* lens but I would look for the extended warranty. In an Edmonton camera store I picked up a K5 with the DA* 16-50 to try it out and that particular lens seemed to be dead, would not autofocus, and since that was my first experience with an SDM I was a little surprised. Would I buy a DA* 300mm, probably but not right away. The DA 55-300 will not be a recent purchase either, I will go back to my old F 100-300mm f4.5-5.6 this summer and wait until I can afford something better (i.e. one of the DA* lenses). Meanwhile this image shows that the DA 55-300 can produce some excellent results when everything comes together. This image has been resized and that is all.
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Pentax K5, K3:
FA 35mm f2, FA 50 f1.4, FA 28-70mm f4, FA 28-80mm f3.5-5.6, F 50mm f1.7, Tamron SP 70-200mm f2.8 Di, DA 10-17 f3.5-4.5, DA 14 f2.8, DA 16-45mm f4, DA 18-55mm f3.5-5.6 WR, DA 50-200mm f4-5.6 WR, AF-540FGZ

Olympus E-P2, E-P5, OM-D E-M1: 9mm to 150mm lenses

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Old May 27, 2011, 2:43 PM   #16
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Hi All,

Re: SDM failures -- Take a look at these threads:

http://www.pentaxforums.com/forums/g...d-locally.html

http://www.pentaxforums.com/forums/p...or-repair.html

The DIY article referred to for disassembly is here:

http://bangmedia.no/pentax/sdmfix/

There are further tips to the DIY repair located further on in the 2nd thread above, so it's a good idea to read the whole thread to pick up the additional tips if you want to try the DIY fix.

The bottom line I get from these is: if your SDM lens fails, try one of the easy fixes first, instead of continuing to try to focus with SDM -- trying to activate a bound motor could burn the motor out.

If the easiest fixes -- rotating the focusing collar numerous times or turning the screw drive screw to turn the focusing mechanism lock to lock a number of times -- don't work, then either try the DIY, or copy the article or its URL and take the lens to a competent lens tech to have him try it. Also copy the wizofoz post about the local repair for the lens tech to try. Either of these fixes shouldn't cost more than a CLA ($100 or less), and I'd try to get the lens tech to try the repair on a contingency basis -- if the repair doesn't work, there's no charge (but I'd pay him something to cover his time anyway. . . and he's gained some experience that might prove valuable in the future. . .).

Scott
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Old May 27, 2011, 3:54 PM   #17
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Ira - not just early SDM lenses. There are numerous people who have returned a lense for SDM repair and then had the subsequent motor fail too. Just because some people have a lense which hasn't failed doesn't mean yours won't .... as Scott's links show.

However by far the two lenses that seem most susceptible to this motor failure are two zooms, the 16-50 and 50-135. It seems that the primes either don't put as much stress on the lense or the zooms have some other reason for their (relatively) high rate of SDM failure ... these are the only two Pentax SDM lenses I would avoid but even then remember that in all probability the SDM failures are still within industry tolerances - ca. 5%. Still, the Extended Warranties should put your mind to rest.

Looks like you have a great plan !
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Nikon : D800, D600, Sigma 500/4.5, Sigma 120-300/2.8, Zeiss Distagon ZF2 - 21/2.8, Zeiss Distagon ZF2 - 35/2.0, Nikkor 85/1.8G, Sigma 50/1.4. Nikon x1.4 TC, Sigma x2.0 TC
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Old May 27, 2011, 5:32 PM   #18
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I think the DA* 300 is my most likely bet as an SDM lens. With that and the DA 70 Limited I feel I would have a very good set of lenses to cover most of my needs. Although I have heard a lot of bad things about the DA 50-200 my WR lens seems to be reasonably sharp and is serving me well in the focal lengths in between. I will use my current lenses until I have saved enough for my new lenses.
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Current equipment
Pentax K5, K3:
FA 35mm f2, FA 50 f1.4, FA 28-70mm f4, FA 28-80mm f3.5-5.6, F 50mm f1.7, Tamron SP 70-200mm f2.8 Di, DA 10-17 f3.5-4.5, DA 14 f2.8, DA 16-45mm f4, DA 18-55mm f3.5-5.6 WR, DA 50-200mm f4-5.6 WR, AF-540FGZ

Olympus E-P2, E-P5, OM-D E-M1: 9mm to 150mm lenses

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Old May 27, 2011, 6:06 PM   #19
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HI Ira,

Regarding your OP, I can't agree more about getting the best lenses you can. They definitely make a difference. Pretty early on, I chose to use a number of sources for lens evaluation, and set some minimum standards that I stuck to when considering a lens. This has been very successful for me.

For older lenses, I used:

SPLOSdb: I've used his * as a minimum rating and haven't been disappointed. The **, !, and !! rated lenses are among the best I own.

http://www.jcolwell.ca/photography/x...OSdb/index.htm

This is outdated since the author switched from Pentax @ 2004, but the information is still good, and the ratings are fair.

Photozone Lens Performance Survey (not the Review section): I usually have gone with lenses rated at least Very Good in center sharpness wide open and haven't been disappointed.

http://www.photozone.de/active/survey/surveyform.jsp

This used to be searchable by Mount, but you can still find Pentax lenses within it, and 3rd party lenses, but some of the 3rd party lenses were never offered in K mount, so it can be confusing. . .

The old Photodo: The old Photodo measured lens sharpness with a weighted MTF score, where anything in the high 3's was very good, and anything over 4 was superb. The scores have been incorporated into the new site's database, and though harder to find, are still available.

The PF Lens Databases are pretty good, but some users are overenthusiastic, and some overly critical, so one needs to weed these out and try to judge who is more or less objective. Regardless, it can be a good source of information. PF started after I'd accumulated most of my lenses, so I didn't use it much to choose my lenses.

http://www.pentaxforums.com/lensreviews/

As far as technique goes, I confess to technological laziness. I use Av priority 99% of the time. I have the front e-dial set for Ev compensation, and with the K-5 use Auto ISO most of the time. I have my Program Line set to favor faster shutter speeds. I have the Info Screen set up so Auto ISO range is highlighted normally, and I can quickly change the higher ISO limit with a push of a button and rotating the rear e-dial.

This is the way the thought process works for birding. I know that my tele lenses have narrow DOF at the closest shooting distance, so the closer I'm shooting, the smaller aperture I need to use to get adequate DOF, so I adjust Av to get the DOF I need. The exceptions to longer distance/wider aperture is BIF, where I want greater DOF to make things easier on the AF system, and situations where it's a rare opportunity, and I want a focusing hedge and/or extra resolution. I also make exceptions to the smaller aperture/closer distance where the bird is in deep shadow and shutter speeds get too slow. This is the reason I shoot Av priority most of the time.

Having the front e-dial set to Ev comp allows me to override the exposure system for birds silhouetted against the sky (where I use +Ev comp), and for full or partial white or yellow birds in direct sunlight where the light colored feathers have a tendency to blow out because they don't dominate the metering area (so I use - Ev comp)

In Auto ISO, with the Program Line set to faster shutter speeds, the exposure system will default to higher ISO before it allows the shutter speed to fall below 1/125, so using up to a 500mm lens with SR, I can usually get sharp results on stationary birds relying on SR to give me 2-2.5 stops of stabilization, which is, IMO about all I can really count on with my relatively good handholding technique. I'll push this a bit, but not too much, so I have to watch shutter speeds when I'm shooting in shadow. With the K-5 I'll usually set the upper limit for Auto ISO at 5000 and will go to 10,000, but only when needed. If I'm in bright conditions, I will limit ISO to 200 or 400 so I need less NR in PP if I want maximum detail. Although I use automation to a significant degree, there's a lot of judgment involved in the application of it.

I shoot jpegs, so camera settings are important, and PP becomes a necessary part of the technique. With the K-7 and K-5, Auto WB works really well, so my cameras pretty much stay there most of the time. If I'm shooting in consistent lighting indoors and have the time, I'll set a custom WB, and shoot with that.

To keep high ISO noise manageable, I set up my camera's image parameters with Sharpness set to -4. I was initially very disappointed with the K-5 at high ISO until I tried this. This makes sharpening in post a necessity, and of course, NR in post has to be used, so I'm glad that I tried Topaz Denoise and Infocus early on, and I rely on these programs to process my images rather than allow the incamera processor. I turned the high ISO NR in the camera completely OFF as it blurs the images more than I like.

Topaz DeNoise cleans the noise without doing much to the details, and straightens up fine edges that are broken up by noise. Infocus sharpens by deconvolution instead of increasing edge contrast, and allows microcontrast enhancement which is both effective and subtle. I use this program by moving the sliders up until I see some artifacts at extreme magnification, then backing down until they disappear. I only use deconvolution and microcontrast.

Another useful sharpening program is Focus Magic, which used to be my default sharpener for years. It's also a deconvolution sharpener, but I think it adds some edge contrast sharpening, so for me, InFocus is better as a general sharpening program. The part where FM shines is the ease with which it can cure minor motion blur. InFocus also has this capability, but it's harder to learn and doesn't do as good a job, IMO.

One last confession -- I shoot center point AF with my subject in the center of the frame and landscape orientation at least 90% of the time. I crop to compose and rely on the ultra high resolution of the new sensors to supply enough resolution to give me the details I want. This, and a lot of other things I do is blasphemy to purists, but I really could care less. I'm neither an artist nor a great photographer, and don't fancy myself as either. I consider myself to be a competent technical amateur digital photographer/processor and am satisfied with that.

My bottom line is that I use all the technology that is useful to me, and embrace new features and capabilities as they come. I know deep down that I could become a better overall photographer by going back to the basics and using my brain to process a lot of information, but in-camera automation allows me to get better results with less fussing, and with birds, speed is really essential.

I am in awe of those who have the artistic vision to truly see photographically, compose in the VF, and paint with the light. The most I can aspire to is to get the right opportunities and take advantage of them as well as I and the capabilities of my camera might allow. I do draw the line at machine gun and pray, and I rarely use continuous frame rate as a crutch, though I do use it on some rare occasions, and always have my cameras set to continuous high just in case. There are just some times when shutter lag, no matter how little there is, will prevent getting the shot I want because the lag, when added to my continually slowing reaction times just make some anticipation and high frame rate the only possible solution.

Confessions over, I think I'll go out and shoot some. . .

Scott
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Old May 27, 2011, 6:14 PM   #20
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Quote:
Originally Posted by Frogfish View Post
However by far the two lenses that seem most susceptible to this motor failure are two zooms, the 16-50 and 50-135.
BTW, like Harriet, I also have a very early DA*50-135, use it a lot, and have had no problems. I have also heard of others who have had nothing but problems, so I really don't know what to think about SDM failures, but I do think that there's something to wizofoz's post. It could be something as simple as inconsistencies within batches of thread lock compound.

Scott
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