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04-24-2010, 06:52 PM   #31
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After I do the math, 12cm is less than 5 inches. Too close. The closest I'm able to focus with mine (MIJ), is about 9 inches from the lens. That's both MF And AF, and it agrees roughly with what the focus scale on the lens barrel shows.



04-24-2010, 06:56 PM   #32
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QuoteOriginally posted by pHREDD D Quote
here in Adelaide no shops have any stock of FA31s and there were only 2 in stock at CRK (Melbourne supplier) when I ordered mine... thus a bit hard to test etc.

I have been doing some more testing and have found that I can get a focus lock (beep sound and all) at 12cm! Can a 31 focus this close?

Also I've been doing my eyebrow test (just taking a portrait approx. 1 - 1.5m away and pixel peeping the results and I can't get a sharp image of eye lashes at f4 or f5.6 at any focus adjustment (K20). ****can anyone point me to or show me a full size or 100% crop with a eyebrow/eye lashes at any aperture (just collecting ammunition when I ring CRK next tuesday)****
Did you shoot those pics with the tripod? or fixed on something?
and did you shoot them with a fast aperture.
I think all above might cause the sharpness.
I tried my FA 31 AIV, which is very sharp wide open, of cause I put my K-7 on the tripod.
04-24-2010, 07:27 PM   #33
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QuoteOriginally posted by stevebrot Quote
Your example photos indicate something much worse than missed focus. I have seen this sort of thing when internal elements were badly misaligned. I would suggest a replacement from the store and would test the replacement lens before leaving the store.


Steve

I concur, My FA31 f/1.8 performs better than this even at infinity @ f/1.8 - either I lucked out and got an exceptionally good one, or yours has misaligned elements in it.
04-24-2010, 09:17 PM   #34
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According to the Pentax Imaging website on the 31 -

PENTAX FA Wide-angle Limited Lens for Digital SLRs and Compacts: smc PENTAX FA 31mm F1.8 Limited

Lens Mount: PENTAX K AF
Lens Construction: 7 groups 9 elements
Angle of View: 70 degrees
Aperture: F1.8
Number of Diaphragm Blades: 9
Minimum Aperture: 22
Minimum Focusing Distance: 12 inches
Filter Diameter: 58mm
Maximum Magnification: 0.16X
Dimensions: 2.6 x 2.7"
Weight: 12.2 oz.
Case: N/A
Objective Cap: N/A
Hood: N/A
Lens Aperture Ring: Yes
Tripod Adapter: No
Diaphragm Control: Fully automatic
Focal Length: 31mm (equiv. 46.5)

04-24-2010, 11:21 PM   #35
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On the focus distance ring mine says the minimum focus distance is 0.3 meters which is roughly 11.8 inches.

and here are the images from my FA31mm f/1.8 Limited on a K-10D - the first image was taken at f/4 and the second at f/1.8 - no sharpening applied in Lightroom or in the export process. My FA31mm f/1.8 is made in Japan s/n 0028652

* and for the record that is my eye, and I lost the eyebrow peircing in an attempted mugging incident last year, and to be honest i'm not getting it put back in...the damn thing would get caught on my pillow as I slept, it Scratched the rear lens on my Leica M7 Viewfinder eyepiece.

Last edited by Digitalis; 04-29-2011 at 05:09 AM.
04-24-2010, 11:51 PM   #36
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Sorry to hear about attempted mugging. Canikonians?????
04-24-2010, 11:55 PM   #37
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LOL no far from it, But I will say that they spent longer in hospital than I did. <evil grin>
04-25-2010, 07:22 AM   #38
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Here is mine, opening with camera-raw, the plug-in of PS4
Mine is AIV version....
f1.8 1/15 handle with SR on


Last edited by henryjing; 04-14-2011 at 06:27 PM.
04-25-2010, 07:34 AM   #39
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As I know, the FA Limited is well-know as sharpness at one stop less than wide-open...
Try again at f2.0 or f2.2
Those who got MIJ version, lucky are they. But if you got the AIV, it's not a bad thing, you can use them in every condition you want, and never worry about it.
04-26-2010, 12:08 AM   #40
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thanks for all those photos...

thats what I wanted to see!!! (or if I was a clearer thinker... thats what I wanted to see using my lens!!!!!!!!) anyhow a phone call tomorrow about my lens.
04-26-2010, 12:30 AM   #41
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QuoteOriginally posted by pHREDD D Quote
thats what I wanted to see!!! (or if I was a clearer thinker... thats what I wanted to see using my lens!!!!!!!!) anyhow a phone call tomorrow about my lens.
Good luck with that

I have to say mine (MIJ) is also sharp wide open - here is a 100% crop wide open:
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