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04-15-2012, 12:48 AM   #1786
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QuoteOriginally posted by mattb123 Quote
Golden eagle from a raptor rehab center
K-5 & 28075 2.8

wowww!

04-15-2012, 07:29 AM - 1 Like   #1787
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With the 28-75 f/2.8, 50mm, f/2.8. I got this lens because I wanted a zoom with a large aperture to use primarily indoors. I bought it used and didn't realize that it has some decentering evident at the wide end along the left edge until after I left feedback. Still a nice lens that produces usable results wide open.


04-15-2012, 03:01 PM   #1788
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QuoteOriginally posted by Designosophy Quote
With the 28-75 f/2.8, 50mm, f/2.8. I got this lens because I wanted a zoom with a large aperture to use primarily indoors. I bought it used and didn't realize that it has some decentering evident at the wide end along the left edge until after I left feedback. Still a nice lens that produces usable results wide open.


Great shot. What is decentering?
04-16-2012, 09:17 AM   #1789
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QuoteOriginally posted by fuent104 Quote
Great shot. What is decentering?
Decentering is the result of an individual lens or lens group within a lens unit being out of place. It usually results in photographs with blurring, smearing, and/or doubling along one side. It's more commonly noticed in large-aperture lenses. Stopping down can usually mitigate or correct the problem. To get it fixed, however, the lens will need to be sent to the manufacturer. With my lens (the 28-75), it only affects the leftmost tenth of the image, and it's only noticeable wide open at the wide end of the focal range. Wide open, at 40mm, it's gone, and at 28mm, by f/5, it's much less noticeable.

04-16-2012, 10:11 AM   #1790
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QuoteOriginally posted by Designosophy Quote
With the 28-75 f/2.8, 50mm, f/2.8. I got this lens because I wanted a zoom with a large aperture to use primarily indoors. I bought it used and didn't realize that it has some decentering evident at the wide end along the left edge until after I left feedback. Still a nice lens that produces usable results wide open.


Darn nice photo! All your portrait shots have looked great, saw the ones with the 30mm, superb...
04-16-2012, 10:36 AM   #1791
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From my yard yesterday after a storm passed over.
Looks like the dandelions will be ok, damn it!
K-5 & 28-75 2.8

04-18-2012, 08:24 PM   #1792
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QuoteOriginally posted by Designosophy Quote
Decentering is the result of an individual lens or lens group within a lens unit being out of place. It usually results in photographs with blurring, smearing, and/or doubling along one side. It's more commonly noticed in large-aperture lenses. Stopping down can usually mitigate or correct the problem. To get it fixed, however, the lens will need to be sent to the manufacturer. With my lens (the 28-75), it only affects the leftmost tenth of the image, and it's only noticeable wide open at the wide end of the focal range. Wide open, at 40mm, it's gone, and at 28mm, by f/5, it's much less noticeable.
Thanks for that description, I think that's the situation with my 16-50. It only became a problem after it was serviced for motor issues. I am not having it repaired again because I no longer have much use for the lens but I will experiment to see the degree to which focal length and aperture mitigate the problem should I want to use it in foul weather or something.
04-19-2012, 05:33 AM   #1793
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QuoteOriginally posted by theunartist Quote
Darn nice photo! All your portrait shots have looked great, saw the ones with the 30mm, superb...
Thanks, Rick. Without zooming in, it's often difficult to tell the difference between shots taken with the 28-75 and a prime. It's got great color and contrast from f/2.8 on. The decentering is only noticeable in landscapes and flat-field photos, which are rare in practice. For portraits, it's almost never an issue.

QuoteOriginally posted by jmschrei Quote
Thanks for that description, I think that's the situation with my 16-50. It only became a problem after it was serviced for motor issues. I am not having it repaired again because I no longer have much use for the lens but I will experiment to see the degree to which focal length and aperture mitigate the problem should I want to use it in foul weather or something.
Ain't that just the way it goes - get repairs for one problem, get it back with a new problem. I'll try to post some photos of the issue with my lens later.

04-24-2012, 01:42 PM   #1794
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QuoteOriginally posted by mikeSF Quote
here is one with the 70-200/2.8 plus 1.4x TC (280mm total).
Wow! I have the same gear but doubt I have the skill to take a pic this nice.

Newbie question - what is TC?
04-24-2012, 01:52 PM   #1795
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QuoteOriginally posted by Sage97 Quote
Wow! I have the same gear but doubt I have the skill to take a pic this nice.

Newbie question - what is TC?
TC is a tele convertor. mine is a 1.4x which means my 200mm on the lens with TC is about 280mm. They are an inexpensive way to add more reach with a slight loss in light and IQ typically.
04-24-2012, 02:19 PM   #1796
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Some cool clouds from last night.

K-5 & 28-75 2.8






This one received a little more PP than usual.







04-24-2012, 02:41 PM   #1797
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awesome skull work. did you dodge and burn? clone? layer image in and blend? etc? looks great.
04-24-2012, 02:48 PM   #1798
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QuoteOriginally posted by mattb123 Quote
Some cool clouds from last night.
Yep, that's the Front Range in central Colorado. I miss it.

H2

04-24-2012, 03:00 PM   #1799
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QuoteOriginally posted by mikeSF Quote
awesome skull work. did you dodge and burn? clone? layer image in and blend? etc? looks great.
Thanks!
Actually this is my first attempt at something like this since getting full Photoshop CS5 recently on sale.
I found some free clip art of a skull and pasted it as a new layer with 30% transparency. Then I scaled that layer to fit what kind of looked like eyes and a chin in the cloud already (making it taller and skinnier).
Then I added a mask and brushed out the parts I didn't want to show from the skull image and went over it a few times with a translucent brush to try and eliminate any hard edges and that was it! Oh, and I did dodge and burn a little at the end to even out the tones. I was amazed at how easy it ended up being! And fun!
04-24-2012, 03:01 PM   #1800
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QuoteOriginally posted by pacerr Quote
Yep, that's the Front Range in central Colorado. I miss it.

H2
Not quite the Front Range, but close enough (Central Rockies, Western Slope). Yeah, I'd miss it if I left too!
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