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Old Jul 9, 2008, 12:10 AM   #1
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I bought a lens last week (before a bear made the Fit unFit). Here are two shots, both jpg straight out of the K20, shot at ISO 1600. I used a wireless flash unit (finally figured out a good deflector for it - a coffee filter) at f5.6. I would have posted 100% crops but the camera focused on slightly different spots (not using a tripod, the pictures were hand-held while standing on a stool). One lens is a zoom lens and one is a prime. See if you can guess which one was taken by which camera, before checking out the exif.

I've posted the full sized files on zenfolio if you want to look at them/download them. Here's the resized versions, resized by whatever means zenfolio does it. Which one do you like better, and why? Or is there much difference?

#1:



and the link to the full sized file is: http://mtngal.zenfolio.com/img/v3/p796789105.jpg

#2:



and the full sized version is at: http://mtngal.zenfolio.com/img/v2/p947157167.jpg

The picture was taken at ISO 1600, with the noise reduction set to weakest (the default is NR off and I just recently put it to weakest, to see what I think of it when using it for regular shots). The full sized versions of these pictures are really rather interesting, both from a camera point of view as well as comparing the lenses.

I'm not sure that there's an obvious winner between the two lenses. They have different capabilities, but they have similar sharpness. By the way, the elephants were bought by my grandfather. He spent timeworking/traveling around the world well before WWII.
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Old Jul 9, 2008, 6:17 AM   #2
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Congratulations Harriet, I have wanted that particular mystery lens for a long time! I am assuming the control lens is your 50-135mm? I looked at both full size images fairly closely. One thing making direct comparison tough is the camera chose slightly different focus points/planes for the two shots. Shot 1 has the rear row of elephants in better focus and shot 2 gets the front row. Both lenses are very sharp in their areas of focus. (OK, you knew all this already).

I have compared in focus area to in focus area and OOF area to OOF area and I can't figure out which is better. I would really like to see more from the new lens and, if you have the inclination, more comparisons. If the 50-135mm is really virtually identical in sharpenss and IQ to a prime within its range, there really is not much point in buying the prime.

Tim


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Old Jul 9, 2008, 6:29 AM   #3
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Image # 2 strikes me as better: a tad sharper, and better contrast which shows less noise than image#1. I'm not such an expert that I can tell which lens is which...do tell!

Jay
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Old Jul 9, 2008, 7:45 AM   #4
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Now I like #1 better since it shows better detail in the reflection of the ivory carvings and seems to show better shadow detail.

Tom
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Old Jul 9, 2008, 8:45 AM   #5
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Both images are very similar, notwithstanding the focusing previously mentioned.

Image one has clear detail on the wooden elephants whilst image 2 had clearer ivory elephants.




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Old Jul 9, 2008, 9:15 AM   #6
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Hi Harriet, as Tim says there is a focussing difference and therefore it is not possible to distinguish between the 2 lenses with these two photos. Repeat photos with very careful attention to both lenses focussed on the rear row of elephants would be good to see. Otherwise in brief, there is nosubstantial difference between the lenses!

cheers

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Old Jul 9, 2008, 12:54 PM   #7
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You bring up a point, Tom. Exif shows the same shutter speed, ISO and aperture, so the pictures should have the same exposure. The second one looks a bit darker, not enough to be called under-exposed but enough that the reflection doesn't show up as well. It seems like the aperture isn't quite the same (I wonder which one is more accurate?).

I'm terrible with comparison shots, there's always some setting or something that's different. I also get very bored with pictures when I put the camera on a tripod and shoot the same thing over and over - I've usually found them inconclusive. And yes, the focus point was different - you can see it clearly in the full sized pictures.

More comparison shots to come - I'm not planning on getting rid of either one and think it will be interesting to do some outdoor shooting. I really am surprised at how well the zoom lens does compared to the prime.
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Old Jul 9, 2008, 1:27 PM   #8
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Hi Harriet,

Can't fault your taste in lenses -- been thinking long and hard about that one forever.

The big advantages to the prime are speed and size. The 50-135 is a great all around people lens, but it's a little intimidating to a lot of folks. The zoom range does help in getting the framing close when you're in a crowd though. . .

Your new prime will shine when you want very limited DOF, and / or slightly better bokeh, and when you need the extra speed. The differences won't be a lot, but I'm sure you'll appreciate them. Every little bit makes a difference.

Congrats! I'm definitely jealous.

Scott
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Old Jul 9, 2008, 3:54 PM   #9
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I did a couple more comarisons at lunch time. Since I was shooting at f2.8, focus was critical and I discovered that while the prime is dead-on, my 50-135 has a bit of back-focus (at least at 75mm and 80mm -are such things consistent through a zoom lens's range?),I think. It isn't a huge amount and since I don't often use it wide open, I hadn't particularly noticed. It's consistent with last night's pictures- I wasn'tas careful last night as I was today with my focus point,so just thought it was operator error. I was moreextact today and still sawit a bit. Guess I'll spend the weekend shooting focus charts and learning how to use the focus adjustment on the K20.

And why is it when I want to shoot comparison shots, I have trouble finding interesting subjects?!
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Old Jul 9, 2008, 8:43 PM   #10
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mtngal wrote:
Quote:
I'm terrible with comparison shots, there's always some setting or something that's different.
Quote:
More comparison shots to come - I'm not planning on getting rid of either one and think it will be interesting to do some outdoor shooting. I really am surprised at how well the zoom lens does compared to the prime.
I would imagine that comparison shots could be quite difficult, probably one reason I have never attempted them. I always appreciate it when forum members post their impressions, shots, and especially comparisons with different lenses. I want a lot more lenses than would be financially prudent and I am looking forward to seeing further comparisons between these two lenses. Maybe you could find a victim for portrait comparison since the 77mm limited seems to be an ideal digital portrait lens?

Tim
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