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Grace Scalzo
02-06-2008, 09:34 PM
I created this image a few weeks ago at a feeder at a state park on Long Island. Light was low and poor. In order to get as much shutter speed as I could, I opened up to f5.6 (Low as I can go on my 500f4 w 1.4tc), bumped the iso to 640. When I examine this image, the focus point is just slightly below the eye, and yet the head/eye area looks soft to me.

So my question, is this a dof issue, or something else. My recent images have lacked sharpness in general, so I'm looking to get to the bottom of this.

Note- I did apply selective sharpening to the head area. Also been experiencing some banding with my Mk2n, Canon thinks my battery pack was too close to the camera body. (You'll see it in the ul corner)

Thanks! SOrry so long.

1/400, f5.6, ISO640, ETTL -3
1DM2n, 500 + 1.4tc

Rod Wiley
02-06-2008, 09:57 PM
There is an easy way to check your focus points in your camera, if their off a little you may be back focusing or forward focusing. Take a large calculator and set it up straight out from the camera, tilt it up alittle so you can see the numbers and point one of the focus points at a number on the calculator and press the shutter button down and see if the camera focuses on the number you pointed at or the number above or below it. If it focuses on the one above it, its back focusing and the one below it its forward focusing. I use a long lens for this so that the DOF will make all but the number I point to appear out of focus. I had that problem with a D1X and Nikon fixed it for me. Hope this helps

Alfred Forns
02-06-2008, 10:52 PM
Grace first check if the lens is sharp Shoot a newspaper flat on a wall Have the lens locked down in the tripod so there is no movement Would try at several apertures If all are sharp then you are looking at camera shake or point of focus selection

Nothing like being confident your gear is working as it should btw if the test is not good Do try the suggestion by Rod

Rod Wiley
02-07-2008, 08:40 AM
When I checked mine I set up the calculator and pointed the focus point at the # 6 and it showed that the # 9 right above it was in focus and the 6 wasn't. With long lens you have such a limited DOF that the focus points need to be right on.

Jim Poor
02-07-2008, 09:09 AM
There is a test chart here:

http://regex.info/blog/photo-tech/focus-chart/

It is better than the calculator for reasons better explained by the person who designed it than by me, but it basically boils down to a low contrast area and a high contrast target keep the camera from accidently locking on to the wrong area. The keys of a calculator can fall at the edge of a focus area and cause the wrong key to be chosen.

Grace Scalzo
02-07-2008, 01:41 PM
Much appreciate the time and thought, Rod, Jim, and Al. Will work on this this weekend and report back with the result.

Fabs Forns
02-07-2008, 10:28 PM
Grace, 1/400 of a second for the 500 plus 1.4X tele is hardly anywhere near where I would consider the optimum performance of the lens. Shooting wide open is adding insult to injury. Sometimes we ask too much of the equipment ;)

Grace Scalzo
02-07-2008, 11:23 PM
I realize that, Fab, but I haven't been happy with any of my images lately and am beginning to suspect something may be amiss. Couldn't possibly be me. :(

Fabs Forns
02-07-2008, 11:27 PM
Are you hand holding or using the tripod?

Grace Scalzo
02-07-2008, 11:29 PM
Using the tripod.