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01-17-2010, 06:48 AM   #31
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Abbazz's Avatar

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Location: Jakarta
Posts: 667
QuoteOriginally posted by blende8 Quote
Ok, what do you mean by a "tack sharp picture"?
Below is a quick shot of my phone.
Sharp enough for me.
100% crop:
Thank you for taking the time to post this sample picture. It does indeed appear sharper than anything that I get from my second copy of this lens, but I find the longitudinal chromatic aberration in the 100% crop (green halo in the out of focus background and purple halo in the out of focus foreground) particularly annoying.

Most lenses appear sharper when used for close-up photography. It's better to judge sharpness on a picture taken at infinity. On both copies of the 20/1.8 that I tried, landscape pictures don't look good with mediocre sharpness and lots of chromatic aberrations.

Here are some comparison pictures taken this morning -- sorry but it was pouring, so I had to put the tripod in my garage to take these boring pictures. You can click on any of them to view it full size.

20/1.8 @ F/1.8:


20/1.8 @ F/2.0:


20/1.8 @ F/2.8:


20/1.8 @ F/4:


20/1.8 @ F/5.6:


24/1.8 @ F/1.8:


24/1.8 @ F/2.0:


24/1.8 @ F/2.8:


24/1.8 @ F/4:


24/1.8 @ F/5.6:


30/1.4 @ F/1.4:


30/1.4 @ F/1.8:


30/1.4 @ F/2.0:


30/1.4 @ F/2.8:


30/1.4 @ F/4:


30/1.4 @ F/5.6:


Cheers!

Abbazz


Last edited by Abbazz; 01-17-2010 at 07:06 AM.
01-17-2010, 07:29 AM   #32
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blende8's Avatar

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Location: Bremen, Germany
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Posts: 1,521
Boah Abbazz, that's bad! I agree.
One can see double images at the antenna and those glowing borders.
Not good!

This is definitely a bad copy of that lens.
Mine does not show this.
01-17-2010, 08:46 AM   #33
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Join Date: Sep 2007
Location: Dayton, Ohio
Photos: Gallery | Albums
Posts: 2,978
Original Poster
@Abbazz and Wielnad,

Thank you for those sample images.

P.S: How do you link images like Abbazz has done where it goes to the full resolution when clicked on it...I know 'imgwide' doesn't do that..........
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