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08-03-2009, 03:31 PM   #1
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Thoughts on these focus tests?

Not seeing perfect results here. It all sort of started when I noticed that the wrong part of a person's face was in focus when I was using the FA 50mm.

Pics taken on a tripod using the two second timer and the AF540 bounced off the ceiling. SR off.

Thanks for looking and letting me know what you think


1)DA 18-55, 18mm@4.5:


2)DA 18-55, 18mm@5.6:


3) DA 50-200, 50mm@5.6:


4) FA50 1.4, 50mm @1.4:


5) FA50 1.4, 50mm @2.8:


5) FA50 1.4, 50mm @5.6:


08-03-2009, 04:46 PM   #2
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Can't say much. Your first two pictures don't seem to be square to the target, so, starting from there, it is possible to question the rigor of your testing. As for the 50 mm. lens, it seems soft wide open, but it seems to improve as you stop down. I'm still skeptical about the validity of your test. Maybe you should go to "Yvon Bourque's blog" and dowload his test target. I think it is more accurate than the one you are using.
08-03-2009, 08:40 PM   #3
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May I suggest that you use this focus chart instead? It has more gradations, so it's easier to differentiate between sharp and soft.

http://regex.info/i/FocusChart-v1.0-gray10.gif

- Jason
08-04-2009, 03:16 AM   #4
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Good chart Jason...thanks mate !!!

08-04-2009, 04:04 AM   #5
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QuoteOriginally posted by inferno10 Quote
May I suggest that you use this focus chart instead? It has more gradations, so it's easier to differentiate between sharp and soft.

http://regex.info/i/FocusChart-v1.0-gray10.gif

- Jason
There is too much "crap" on that focus chart. You can never be sure where your focus sensor locked focus. Look at the chart on Yvon Bourque's blog. The way it's designed, you know exactly what your focusing sensor locked on.
08-04-2009, 08:20 AM   #6
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QuoteOriginally posted by inferno10 Quote
May I suggest that you use this focus chart instead? It has more gradations, so it's easier to differentiate between sharp and soft.

http://regex.info/i/FocusChart-v1.0-gray10.gif

- Jason
You should link the explanation page because there are many different versions of this chart with various level of grays. You have first to make sure that the camera cannot lock on to the grey parts.
08-04-2009, 10:47 AM   #7
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I use a chart mounted on cardboard that pivots on a rod. The chart is turned so that it is parallel to the sensor for focusing then turned 45 degrees for exposure. That way there where is no question where the camera focused
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