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Old Jul 10, 2008, 12:07 AM   #11
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I did manage to take a few pictures at lunch, though only one comparison shot, which convinced me that the 50-135 is back-focusing a little bit.

First, the 77 Ltd. as a portrait. I re-posted this version in the Lens thread asking whether the 77 is worth the extra cost because my first version was so lousy looking when I got home. ISO 100, f1.8, 1/2000 (it was an overcast noon hour).



Then, the 77 as a street lens. No, this is not the bear thatran into our car on Monday. Though I did joke a bit about killing my employer's mascot a bit. The sun was starting to peak out of the marine layer so it was mostly hazy with lots of glare. ISO 100, f3.2, 1/500 sec.



I had originally shot this picture as an example of bokeh for portraits and used f3.2, assuming that you wouldn't necessarily shoot wide open for portraits. This is not a permanent thing, Royce is substituting for the Vatican for a couple of days. The lens shows that this isn't the real thing (or that good of a copy). Here's the full frame picture, just resized:



And a 100% crop taken from the bottom middle:



I didn't take any pictures here with the 50-135, felt a little funny with all the security people around keeping an eye on the props and incredible amount of equipment.

I did take a couple of comparison shots. It's not exactly the most exciting object, but it has all kinds of lines, tones and depth to it. I've posted the jpg files straight out of the camera if you are interested in comparing them full sized.

77 Ltd at 2.8, ISO 100, 1/100 sec., resized by zenfolio:



The full sized file is at: http://mtngal.zenfolio.com/img/v3/p664017269.jpg.

DA*50-135, 75mm, f2.8, 1/100 sec. ISO 100, resized by zenfolio:



Full sized file at: http://mtngal.zenfolio.com/img/v3/p976540462.jpg.

You can see on the full sized version that while I carefully focused on the upper center corner of the light, the lens focused a little behind that.

Finally, just for interest sake, I took the same picture with the 77 Ltd. at 1.8 (1/200 sec.) There's a bit of purple fringing when it's wide open that you don't see at f2.8, and it's only a very small amount (I've seen far worse). It's still tack sharp.



And the full sized file is at: http://mtngal.zenfolio.com/img/v3/p647901279.jpg.

Remember that the jpg files from the K20 are huge.

I'll do more of a write-up on the lens this weekend. My conclusion is that the lens lives up to it's reputation, I love the lighter weight and smaller size, and I think the DA*50-135is an under-rated lens.


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Old Jul 11, 2008, 9:58 PM   #12
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Harriet,
I'm surprised with these shots. (in the smaller pics) It's interesting, the limited has better contrast but, at f2.8 the DA* has a tad more saturation. IMHO. And, unless you really LOOK for it, you don't notice any fringing like #3 the best overall. That said, when I go full image, the DA* looks softer but, overall more of the image is in focus than the Prime and the Prime shows more fringing. On the DA* I think its more softness than fringing. It would be fun to see which would look best with a little PP. I think they're both great lenses! Of course, if you ever feel like parting with oneā€¦:G
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Old Jul 11, 2008, 10:41 PM   #13
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On the chandelier shots, I am going with the 77mm limited, even wide open, over the 50-135mm. You have not shown me anything yet that would make me cross either lens off my wish list Harriet. My wife would probably be willing to commission you for such a shot though. . .

Tim :lol:
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Old Jul 11, 2008, 11:25 PM   #14
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I thought the DA looked a bit soft until I looked closer - the lens backfocused a bit, leaving the spot that I carefully focused on (the upper middle join of the light) soft because it is slightly out of focus. If you look at the various chains and the back post, you can see the sharpness and focus point of the zoom. I'm going to have to check the focus on it this weekend because I'm pretty sure it's backfocusing, while the Limited is right on, so it appears soft when it really isn't.

One of the things about the Limited is that it has a built-in retractable lens hood. The lens cap isn't the pinch type you normally see - both the hood and the cap are metal. The cap is lined with something like felt (not sure what it is exactly) and just slips onto the outside of the hood, pretty tightly. Usually the lens hood extends out as you pull the cap off (which is very convenient). The DA50-135 has a big lens hood that is the bayonet mounted type. Since it's so long, I leave it mounted backwards on the lens, putting it on correctly when I think flare is going to be a problem. Since it was such a grey day I didn't bother putting the hood on front-wise and also didn't bother removing the UV filter I leave on it much of the time now so there could have been some flare, the reason for less contrast perhaps? Hopefully I'll have a chance to shoot some more comparison shots tomorrow (the week is FINALLY over!) and get a better idea.

I really will do a better review of the lens this weekend. I already have some of the pictures taken, but still want to shoot a bit more to get a better idea of it. I haven't had much time recently.
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Old Jul 12, 2008, 4:00 PM   #15
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Looks like a keeper lens to me!

The guy next door hit a bear with his Minivan and the State told him he could have it if he wanted. Bear steaks on the grill are extremely good it seems, although a bit rich, must be the high fat content.

I always wondered how one of the mini station wagons would hold up in an accident, so how did the Fit fare?

Tom
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Old Jul 12, 2008, 5:09 PM   #16
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Okay... so here's a question: What does Harriet do about the back-focusing issue? By her own count, this has popped up in more than one of these images. And, somehow, I don't think Harriet is the problem. Or isn't the problem enough of a problem to pursue a solution?
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Old Jul 13, 2008, 10:22 AM   #17
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From what I can see here Harriet, both lenses are very good. I had a 77 quite some time ago, and it backfocused a lot. Sent it back, and never did replace it. I would say your copy is excellent! I really wouldn't be able to choose the better shots from either lens looking at normal viewing sizes. At 100%, I'd pick photo #1, but they're very close. The bokeh on these shots is excellent..cheers...Don
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Old Jul 13, 2008, 1:02 PM   #18
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Tom - still no word from the insurance company about the Fit - my hubby thinks they'll total it but I think the damage is all body damage and repairable. I'm on pins and needles because we're still upside down on the loan.

Biro - I have two choices with the 50-135. I have the K20, so I was planning on spending this weekend shooting focus charts to verify just what it's doing. The K20 has a way of adjusting the focus for specific lenses, so I thought I'd do that first. However, I'm now thinking of sending it into Pentax - yesterday morning I spent some time sort-of hiking with the 50-135 on the K100 and the 77 on the K20. While I hadn't noticed any backfocusing with the K100 before, I did yesterday so now I'm beginning to think I've damaged the lens in some way and should send it back. I'll know more when I get a chance to shoot charts.

I got called out of town suddenly yesterday, so I don't have access to the pictures I took. However, the better contrast of the 77 were really evident in the pictures I took and this time I had the lens hood in placeA couple of the 77 "pop" more than the 50-135 (though that might have been influenced by the fact the 50-135 was on the K100, but I don't think so). I'm beginning to see why it has such an incredible reputation. It does have a bit of purple fringing when shot wide open (you can see it in some of the 100% files I've already posted), and there's a little bit of CA. By 2.8 it pretty much goes away.

Yesterday I discovered another advantage to the 77 that I hadn't thought about - it has a closer minimum focusing distance than the 50-135. It's not a macro lens, but it's going to be OK for flowers.
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