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10-22-2014, 10:25 PM   #16
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Here are some tests I ran with various lenses. Not the most scientific, but I did use a tripod and did my best to maintain a parallel plane to the wall. The exposures varied wildly due to p-ttl being employed so I just auto corrected them in lightroom.

https://www.dropbox.com/photos/album/yYfCHwWjbG9WD2N

My k-7 showed about the same. Looks like my k-5's mount is mostly ok, but a bit weak in the upper left. It was a refurbished camera from keh so I might see how much longer I have on the warranty and send it in for a checkup if I ever get a damned working k-3. Same goes for my 17-70 which is also about 5 months old. I don't know what's going on there at f4, but I don't like it. I think it should go in for a warranty check too while I still can, though I could probably mostly live with its deficiencies since I generally shoot at smaller apertures. Its certainly not a perfect lens. The 55-300 is looking downright awful! The 50-200 is looking much better at the same focal length so I really have to blame the lens here. The only lens that looks all that great is the 50mm. Even wide open it looks pretty decent for the most part.

What I can't help but notice is this: Even an imperfect copy of the 20-40 is currently outresolving every lens I own including A 50/1.7 which was previously the sharpest lens that I owned. Jpeg file sizes are 16mb compared to the 6mb or so the other files have. Also the 55-300 is churning out larger files than the 50-200 even though is is really decentered looking. The 50mm at F8 gives a 10mb file. It outresolved my k-7. On the k-5 IIs, not so much.

This makes me seriously want a good copy of the 20-40. Its really good!

On the other hand I just spent a total of 3800 on gear over the past few months that all has serious deficiencies and that is going to require time and more money to fix. Ugh! Am I being too picky here??

10-23-2014, 12:55 AM   #17
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QuoteOriginally posted by zosxavius Quote
Am I being too picky here??
A tad...

"The closer you get to perfection, the easier it is to see how far from it you are."
10-23-2014, 05:07 AM   #18
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I would expect better from 3800 worth of gear to be honest...

I don't see why anyone would be really happy with the performance I am seeing here.
10-23-2014, 06:32 AM   #19
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Don't think the link is working.....
https://www.dropbox.com/sh/3ui3tzoxwaohjcr/AAD8PPe02ryU738wCcyQD4Bfa/Lens%20Tests?dl=0


Last edited by zosxavius; 10-23-2014 at 06:39 AM.
10-24-2014, 03:44 AM   #20
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I shouldn't have written this 20-40 off. It performs far, far better in the real world. My copy might still be a hair off, but I'm not going to be able to tell until I get a good k-3 to put it on. Looks like my k-5 IIs might possible have a misaligned mount since now that I've thought about it, everything I tested was softest in the upper left. If I ever get a good k-3, I'll send in my k-5 for a checkup. Its still technically under warranty. I'm gonna test this 55-300 more, but it looks like the worst of the two so its probably going back with my k-3 if they ever get more k-3s in.
10-24-2014, 07:15 AM   #21
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QuoteOriginally posted by zosxavius Quote
This is what you are using to test your equipment? hmmm.... Did you get that method perhaps from something like this ? https://archive.org/stream/124waysyoucantes010522mbp#page/n9/mode/2up All kidding aside you may want to use a slightly more modern and better testing method.
10-24-2014, 07:47 AM   #22
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Oooh. Good read. Actually for my needs text on a wall is perfectly adequate but not the most scientific I agree. I tend to consider real world results far more than lens test charts. I actually have a test chart but it was pretty packed away the other night and I just wanted to see what thinks looked like on a flat surface. Thanks for the book though. I fully intend to read it.

---------- Post added 10-24-14 at 10:48 AM ----------

I'm still awaiting new k-3s at adorama. I'll test the 55-300 some more and wait for another camera to come up with a verdict here. The 20-40 is already better than every lens I own!
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