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Old Mar 1, 2009, 1:03 PM   #1
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I am very pleased with the sharpeness of this lens, just a word of warning, mine was heavily front focusing. I went to the max K20d focus adjustment of -10 and it is looking good.

Ed

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Old Mar 1, 2009, 1:04 PM   #2
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Old Mar 1, 2009, 1:05 PM   #3
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Old Mar 1, 2009, 2:12 PM   #4
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Looks like you are getting along quite well with this lens.
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Old Mar 1, 2009, 7:05 PM   #5
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Hi Ed. You are entitled to be very pleased with the lens. Nice sharpness. I'm interested how you set the focussing. Did you do it at 500mm zoom? Did you use a focussing chart, and what distance away? I set the focus for all my lenses, but not sure if I have ever done it for my Bigma.

cheers

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Old Mar 1, 2009, 7:19 PM   #6
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Lookin' goood!

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Old Mar 2, 2009, 12:22 PM   #7
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I used a chart I downloaded on line that has the distances continually verying to compensate for the difference in distance. Lens was on tripod so it was at 45 degree angle to the chart (on the floor). I was zoomed to 500mm and set up at the closes distance focus could be acheived at f/6.3 to minimize depth of field and used 2 sec. timer with mirror lock up. The chart has a focus point labled Focus Here. When i took the first photo the focus point was almost in focus, the text at 25 to 35 mm in front of the focus line was easily redable, the text 25 to 30mm behind the focus point was not readable. I got to adjustment of _10 and the focus line was clear as a bell and the text in fron and back was readable but blurred.

Hope this helps. I would have to do some research to find where I downloaded the chart and instructions, someone on the forum probably has it.

Ed

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Old Mar 2, 2009, 4:15 PM   #8
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Thanks Ed.

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Old Mar 4, 2009, 12:09 PM   #9
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snooked wrote:
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. . .I would have to do some research to find where I downloaded the chart and instructions, someone on the forum probably has it.

Ed

Attached photo is -10 adjustment
Here is the link to the focus chart: http://focustestchart.com/focus21.pdf
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