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01-03-2009, 10:53 AM   #1
Igilligan
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Pf with the FA 50 1.4?

So we always warn folks who ask about the Tamron 70-300 we caution them about the PF that that lens has. But I seldom see a warning about the PF in the FA 50's
Recently while doing some shots with my FA 50 1.4 and 1.7, (don't ask) I have seen a lot of PF at high contrast points in the scenes. Even stopped down.

I tend to use it that lens in low light, so I have not seen it as much before (except aroung light sources in lowlight. Also I have recently switched to the K20 and its bigger sensor.

Has anyone noticed a PF increase with the FA 50 and the K20 sensor? Or has it always been there and I just dont use it in good light enough?

Thanks

01-03-2009, 11:02 AM   #2
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QuoteOriginally posted by Igilligan Quote
So we always warn folks who ask about the Tamron 70-300 we caution them about the PF that that lens has. But I seldom see a warning about the PF in the FA 50's
Recently while doing some shots with my FA 50 1.4 and 1.7, (don't ask) I have seen a lot of PF at high contrast points in the scenes. Even stopped down.

I tend to use it that lens in low light, so I have not seen it as much before (except aroung light sources in lowlight. Also I have recently switched to the K20 and its bigger sensor.

Has anyone noticed a PF increase with the FA 50 and the K20 sensor? Or has it always been there and I just dont use it in good light enough?

Thanks
I just accept that pretty much any lens can be made to show some sort of failure in some conditions.
That's what good RAW converters are for.
01-03-2009, 11:23 AM   #3
Igilligan
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I agree

These were just normal outside conditions. So It is not like I was trying to push the lens to the brink. They were AF adjust test shots so I was pixel peeping to check for sharpness and noticed some PF in almost every shot. I was just wondering if the extra resolving of the K20 sensor may just be part of the issue? Or if it was always there but I never really looked in close that often?

Thanks for the feedback
01-03-2009, 12:48 PM   #4
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I just purchased the FA50 F1.4 yesterday (loving it!!). I've read that this lens, in particular, is prone to PF at very wide apertures and in high contrast scenes.

I usually shoot F/2 to F4 so it's not a big deal for me... yet.

01-03-2009, 01:31 PM   #5
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QuoteOriginally posted by Igilligan Quote
These were just normal outside conditions. So It is not like I was trying to push the lens to the brink. They were AF adjust test shots so I was pixel peeping to check for sharpness and noticed some PF in almost every shot. I was just wondering if the extra resolving of the K20 sensor may just be part of the issue? Or if it was always there but I never really looked in close that often?

Thanks for the feedback
You mentioned that you saw the PF in the high contrast areas of the scene. This is where it will manifest, no matter what the rest of the scene looks like. I've never really gotten a good handle on what causes PF. From what I've read, it isn't a normal chromatic aberration, but some sort of chromatic interference between the lens and the sensor.
Pretty much any lens can be forced to PF, given the right conditions.
I suspect that the higher the pixel density of the sensor, the more easily PF will show itself, but this is the same of any lens aberration.
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