I swapped my D300 out at the local store and have done some quick hand held (yeah, I know) focus tests.

This is from the 18-70 kit lens, min focus distance @ 70mm, f4.5, 1/80s originally 14bit uncompressed raw.

The focus point was the centre of the eye.

Does anyone think this is acceptably in focus?

It's about a 100% crop and I have made base adjustments.



Edited by Soupdragon on May 16, 2008 at 11:42 AM GMT

Plane of focus looks about right, eye detail and your reflection in it clear. For a kit lens handheld at 1/80th (could still be some camera or head movement) up close where you probably weren't perfectly parallel to the young lady's face, it came out fine.

Only real way to tell is focus test on tripod with good, known lens. That said, I'd take it home to test. Nice eyes by the way.

Focussing in the centre of the eye is asking for trouble, because you are focussing on your own reflection and the focus should be twice the distance.

Anyone know what the DOF would be with the mentioned parameters?

If you're trying to use the 1/<focal_length> rule then you should have the shutter speed up to at least 1/100 on a DX body. The DoF with those settings is only 1.2cm (http://www.dofmaster.com/dofjs.html) which is why the top lashes are OOF and the bottom left ones are sharp. Agreed with the focusing on the reflection noted above.

In short it looks more than acceptable to me.

Thanks for the confidence boost!

You should really try these focussing tests on a focus chart (or a brick wall hah!). Google for one. Remember that your D300 has the lens adjustment feature, so that if you find one of your lenses back- or front-focussing, then you can fix it easily.

Nice discussion in this thread!

user error.

louis fusco wrote:
user error.

??

looks excellent to me, but maybe you could select another focus point and recompose to make the result more predictable...

Guy

gugs wrote:
looks excellent to me, but maybe you could select another focus point and recompose to make the result more predictable...

Guy
+1

hjanssen wrote:
Focussing in the centre of the eye is asking for trouble, because you are focussing on your own reflection and the focus should be twice the distance.

Does it really work that way?

If I take a photo of a mirror that is five feet from the camera but the image seen on the mirror is a mountain 20 miles away, is my camera focussing at five feet or 20 miles?

Greg

Greg Matty wrote:
hjanssen wrote:
Focussing in the centre of the eye is asking for trouble, because you are focussing on your own reflection and the focus should be twice the distance.

Does it really work that way?

If I take a photo of a mirror that is five feet from the camera but the image seen on the mirror is a mountain 20 miles away, is my camera focussing at five feet or 20 miles?

Greg


Yes, it really works that way. In the scenario you describe, the camera will focus at infinity (i.e. 20 miles). The image of anything in a flat mirror is as far behind the mirror as the actual object is in front of the mirror.

Andre Labonte wrote:
Greg Matty wrote:
hjanssen wrote:
Focussing in the centre of the eye is asking for trouble, because you are focussing on your own reflection and the focus should be twice the distance.

Does it really work that way?

If I take a photo of a mirror that is five feet from the camera but the image seen on the mirror is a mountain 20 miles away, is my camera focussing at five feet or 20 miles?

Greg


Yes, it really works that way. In the scenario you describe, the camera will focus at infinity (i.e. 20 miles). The image of anything in a flat mirror is as far behind the mirror as the actual object is in front of the mirror.


I guess that's not the case with this example, if it were, nothing except my reflection would be in focus.

Soupdragon wrote:
louis fusco wrote:
user error.

??

well small dof, both subject and camera are not fixed, eyes lids move very fast, your expectations seem very high, at 1/80th the mirror effects sharpness, looks good to me.