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12-24-2015, 02:59 PM   #31
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Thanks so much for taking the time to create the database, and thanks for sharing this very useful information!

12-24-2015, 03:11 PM   #32
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QuoteOriginally posted by pathdoc Quote
I know there are charts for much older lenses (M, A, even K)
Really... is it possible you could point me in the right direction for those, well at least the A series, as I can't honestly I've seen the lowdown on my Ladies.
12-24-2015, 03:13 PM   #33
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This is very useful since I often don't know what the optimal resolution is for a lens and have to guess. I'll have to create a list for the lenses I have. thanks
12-24-2015, 03:52 PM   #34
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Thanks for the information. I can now use "aperture versatility" as another factor on what lenses to buy.

12-25-2015, 08:16 AM   #35
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QuoteOriginally posted by BigMackCam Quote
I also took the plunge and registered a Google account so I believe this gives me the capability to to store it online and allow access to it.
Yes it does.
You can have it publically viewable and then link it in this thread.
12-26-2015, 04:37 PM   #36
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Thanks for that mate, excellent stuff, cheers. I can see it expanding into a wonderful resource for information on many lens sweet spots
09-15-2016, 06:36 PM   #37
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I only found this chart today and linked it into a current resolution thread. Thanks for the work, though I own no Pentax.
09-16-2016, 12:16 AM   #38
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You're welcome. I've been meaning to expand on it, and I will get round to it eventually!

09-23-2016, 02:56 AM   #39
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Thanks a lot for sharing. I would like to see also the result with the FA85*
09-27-2016, 07:13 AM   #40
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It seems a very useful tool, but after a quick look two things stand out to me: DA 18-55 'excellent' wide open at f/3.5?! I don't think so. And I'd rate the DA 35 f/2.4 'very good' at f/2.4 and f/2.8, and excellent beyond.
09-27-2016, 11:43 PM   #41
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QuoteOriginally posted by FantasticMrFox Quote
It seems a very useful tool, but after a quick look two things stand out to me: DA 18-55 'excellent' wide open at f/3.5?! I don't think so. And I'd rate the DA 35 f/2.4 'very good' at f/2.4 and f/2.8, and excellent beyond.
A couple of things to bear in mind:

(1) This spreadsheet shows resolution performance - it does not take into account aberrations
(2) The data used was collated from major test sites such as LensTip and Photozone - not my own measurements
(3) The tests will have been performed on different resolution sensors, some of them now quite old (what was "excellent" back then may only be "acceptable" now)

I wouldn't recommend using this for absolute assessments of a lens' performance, or comparing absolute performance of multiple lenses. Rather, it's most useful for assessing a single lens' relative performance across a range of common aperture settings, at the frame centre and borders.

That said, looking at the DA18-55 results, I think I've made a transcription error there. I'll look at it when I next review the spreadsheet - thanks for pointing it out
10-02-2016, 10:01 AM   #42
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Results will change for different pixel pitches - not only for maximum resolution, but also for diffraction limitation for large f/numbers.
As a general hint this chart is really nice, but not yet comprehensive.
10-02-2016, 02:44 PM   #43
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QuoteOriginally posted by zapp Quote
As a general hint this chart is really nice, but not yet comprehensive.
Indeed not. Hopefully I'll get round to doing some more updates shortly, but otherwise it stands as testament to the fact that you get what you pay for
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