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10-22-2010, 05:40 AM   #1
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k5 afc Case Study

Just thought I would post these. The car was travelling at about 60mph towards me. I locked on when it came into view and shot top quality 16mp jpegs until it came close enough to go out of focus due to being closer that the minimum focusing distance of the lens.

Please look and judge for yourselves the ability of the K5 to track and keep in focus a moving subject. Shot wide open at 2.8 to make focusing as difficult for the camera as possible. ISO 100 on a 70-200 Sigma no PP just resized for web. Camera set on 5 point AFC.

Viewing these at full size on my 30 inch monitor you can see the crazed paint on the number plate on these.

I hope the shots stay in the order I shot them in! I will post 5 shots per reply as I cant get more than 5 on one post.


Terry


Last edited by telfish; 01-30-2011 at 10:19 AM.
10-22-2010, 05:43 AM   #2
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second lot

These are the second lot.

Last edited by telfish; 01-30-2011 at 10:19 AM.
10-22-2010, 05:45 AM   #3
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Third lot

These are the third lot

Last edited by telfish; 01-30-2011 at 10:18 AM.
10-22-2010, 05:46 AM   #4
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Last ones

Here are the final three shots


Last edited by telfish; 01-30-2011 at 10:18 AM.
10-22-2010, 05:52 AM   #5
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Looks great to me!
Any idea how fast the car was traveling?
10-22-2010, 05:54 AM   #6
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It's in the first post 60 MPH
10-22-2010, 05:57 AM   #7
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Speed

QuoteOriginally posted by JohnBee Quote
Looks great to me!
Any idea how fast the car was traveling?
Speed was about 60 miles an hour. This is the main east west route along the St Lawrence river and people do not drive it below 55.
10-22-2010, 05:58 AM   #8
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the way i see it, the first set..the focus seems to have issue locking on or could be the iso noise from camera. Could be the shadows from the trees as well.

set 3 is well captured.

10-22-2010, 05:59 AM   #9
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Looks pretty good to me.
Now do someone running directly towards the camera That's a classic AF test I've seen on some of the review sites.
10-22-2010, 06:00 AM   #10
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Anybody know how much of the K5 AFc's ability will carry over to the Kr?
10-22-2010, 06:10 AM   #11
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Resize is not helping the far shots.

QuoteOriginally posted by Reportage Quote
the way i see it, the first set..the focus seems to have issue locking on or could be the iso noise from camera. Could be the shadows from the trees as well.

set 3 is well captured.
That may be a result of resizing for the web. On my full size samples I can read the number plate lettering on even the first shot where the camera is still locking on. I made this as difficult as I could for the K5, shallow DOF shadows across the frame, hand held at 200mm. If anyone has a file hosting service I could upload the set too I would be pleased to do that.

Terry
10-22-2010, 06:18 AM   #12
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THANKS! That was the test I was waiting for, but still I wonder how K-5 will perform in motorsports with much more accelaration and speed.
Was AF making corrections from time to time or was it going fluently (predictive?)?
10-22-2010, 06:21 AM   #13
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QuoteOriginally posted by telfish Quote
That may be a result of resizing for the web. On my full size samples I can read the number plate lettering on even the first shot where the camera is still locking on. I made this as difficult as I could for the K5, shallow DOF shadows across the frame, hand held at 200mm. If anyone has a file hosting service I could upload the set too I would be pleased to do that.

Terry
I did send you a PM about the file hosting part in you're message
10-22-2010, 06:24 AM   #14
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Its hard to draw any conclusions from the first half of the shots as I look at the trees it does not seem to change focus very often. The closer shots look like its working! I am trying to do a similar test with a sea gull flying towards me but no complete results yet.

Were you holding the shutter button fully down the entire time in 7fps mode or working from the half-pressed mode and clicking off individual shots quickly?
10-22-2010, 06:26 AM   #15
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Files upload

QuoteOriginally posted by Priyantha Bleeker Quote
I did send you a PM about the file hosting part in you're message
Thanks, I will upload soon. Might take a while slow upload speed.


Terry
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