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08/12/2007 06:03:23 PM · #1 |
I have a 90mm macro lens on my D40 (135mm equiv.) - I'm trying to figure out if I'm having problems with focus/backfocus, motion blur, or just very narrow DOF. When I clicked I could have sworn the bright water droplet top-right was in sharpest focus;
Straight out of camera:
//www.flickr.com/photo_zoom.gne?id=1096157403&size=l
Here I was using fast shutter speeds from 1/400s to 1/1000s, shooting at between f/2.5 and f/4 (manual lens, so I didn't record the exact parameters for that shot) - I know the DOF is razor-thin and it was also quite windy, so it's *also* possible that my point of focus moved at the moment I clicked. (As you can see there are points on the stem which *are* in focus) |
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08/12/2007 06:05:57 PM · #2 |
if you shot it handheld, you probably moved.
It is extremely difficult to not be rocking backwards and forwards slightly when shooting this sort of stuff handheld.
If you really want to know if you have a camera problem, shoot something at a similar distance with the camera on a tripod and a subject that can't move.
Message edited by author 2007-08-12 18:06:33. |
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08/12/2007 06:06:33 PM · #3 |
Originally posted by jhonan:
I know the DOF is razor-thin and it was also quite windy |
If you were at max magnification at f/2.5-f/4 and it was windy I'm 90% sure movement was your issue. It's hard enough to shoot handheld without wind. Shooting in windy conditions may make macros impossible. |
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08/12/2007 06:27:15 PM · #4 |
Thanks for the replies. I suspect my rocking backwards and forwards combined with the wind movement is indeed the cause!
To put my mind at rest, looks like it's time to find that metal ruler again. :) |
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08/12/2007 07:35:17 PM · #5 |
Okay, you were both right. Here's a test shot on a tripod where I focused on the word 'Alarm' (at f/2.5)
//www.flickr.com/photo_zoom.gne?id=1097206741&size=l
What amazes me is that this aperture gives me about 1cm of focus. Or put another way, plus or minus 5mm... hmmm... I wonder did my body move more than 5mm during that flower shot? :) |
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08/12/2007 09:58:46 PM · #6 |
Originally posted by jhonan:
What amazes me is that this aperture gives me about 1cm of focus. |
It amazes me to. I wouldn't expect more that 1 mm of DOF at F 2.5
Edit: Heck I hadn't looked at the image on flickr. It looks like about .5mm would be about right at F2.5. Your watch was not parallel
to the plane of the sensor or all the words under the crystal would be in focus.
Message edited by author 2007-08-12 22:02:23.
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08/12/2007 10:00:06 PM · #7 |
;)
 |
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08/12/2007 10:05:35 PM · #8 |
Originally posted by Gordon:
;)
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35mm equiv. of 695mm??????
HUH???
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08/12/2007 10:07:04 PM · #9 |
Originally posted by fir3bird:
Originally posted by Gordon:
;)
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35mm equiv. of 695mm??????
HUH??? |
pbase was coded by a man. |
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08/12/2007 10:13:03 PM · #10 |
Originally posted by Gordon:
pbase was coded by a man. |
Could have been coded by a woman. Number would have been much smaller then. ;)
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08/12/2007 10:13:33 PM · #11 |
Originally posted by fir3bird:
Heck I hadn't looked at the image on flickr. It looks like about .5mm would be about right at F2.5. Your watch was not parallel
to the plane of the sensor or all the words under the crystal would be in focus. |
No, it wasn't parallel to the sensor. I shot it at an angle so I could see where the DOF started and ended. |
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08/12/2007 10:15:21 PM · #12 |
Originally posted by fir3bird:
Originally posted by jhonan:
What amazes me is that this aperture gives me about 1cm of focus. |
It amazes me to. I wouldn't expect more that 1 mm of DOF at F 2.5 |
Actually... yeah, you're right..... My watch was only off at a slight angle. The DOF was probably more like 1mm! |
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