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Old Apr 25, 2007, 9:42 PM   #21
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This is a small section of the previous image, showing the chromatic aberration.
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Old Apr 25, 2007, 9:43 PM   #22
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This is a small version of the test pattern taken from 3 meters away with "(D)" at max zoom. ISO 100. f/8.
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Old Apr 25, 2007, 9:43 PM   #23
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This is a small section of the previous image, showing the chromatic aberration.
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Old Apr 26, 2007, 7:40 AM   #24
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TCav wrote:
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This is a small version of a test pattern I put together in Visio. (Hint: Don't stare at it for very long.)

(I would appreciate any comments anyone might have about this target.)

I printed this out at max res on high quality glossy photo paper, hung it at the height of my camera while mounted on my tripod. I set the self-timer to 2 seconds, and took shot after shot, varying only the aperature and the focal length. (An interesting way to spend an afternoon.) (Metrology is my life. :?)
I like your test targets - these are some of the better organized ones I've seen for sharpness testing. BTW: You're right! It messes with your mind when you zoom in and scroll around!

So have you decided which lens you prefer?
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Old Apr 26, 2007, 8:46 AM   #25
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FrankD wrote:
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I like your test targets - these are some of the better organized ones I've seen for sharpness testing. BTW: You're right! It messes with your mind when you zoom in and scroll around!
Thanks. I was actually getting headaches while I was making it.

On the original, you can actually resolve the one degree radial pattern midway between the end and the first tickmark, but in test shots at 300mm, I was only resolving to 2 or 2.5 with the (D) and even up to 3with the "I". And CA screems out at you. I still use a brick wall for barrel and pincushion tests though.

These aren't absolute measurements, so you can't compare lenses with different focal lengths, but it definately helped me with the task at hand.

FrankD wrote:
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So have you decided which lens you prefer?
Yes. The (D) is sharper. It costs a little bit more, but I'll stick with it. The "I" is going back.

I actually got started with this because I wanted to use my Minolta 18-200 to take some shots of that lunar eclipse almost two months ago. I had been experimenting with moon shots for about a week before the eclipse, but I couldn't get any decent shots. That's when I decided to get a longer, sharper lens. The (D) is a lot sharper at 200 than the 18-200, and the 18-200 has CA at 200 while the 75-300 doesn't.
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Old Apr 28, 2007, 1:10 PM   #26
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Tcav,

Sorry to bug you again - do you know if the hoods are interchangeable between the "I" and "D" versions?

I just received an "I" version but it came without a hood. KEH has a "D" hood listed on their site which I'll purchase if it fits the "I" series lens.

Thanks,

--FrankD

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Old Apr 28, 2007, 5:19 PM   #27
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Old Apr 28, 2007, 7:27 PM   #28
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FrankD wrote:
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I just received an "I" version but it came without a hood. KEH has a "D" hood listed on their site which I'll purchase if it fits the "I" series lens.
My "I" didn't come with a hood either. But every indication is that all the Minolta AF 75-300/4.5-5.6 lenses use the same bayonet type hood EXCEPT the original (the "Big Beercan"). The same lens hood should even fit Sony's version of the lens.
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Old Apr 28, 2007, 8:42 PM   #29
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TCav wrote:
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My "I" didn't come with a hood either. But every indication is that all the Minolta AF 75-300/4.5-5.6 lenses use the same bayonet type hood EXCEPT the original (the "Big Beercan"). The same lens hood should even fit Sony's version of the lens.
OK, thanks TCav.

I'll get one and hope for the best.
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