| Joined: | Thu Apr 19th, 2012 |
| Location: | United Kingdom |
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I was confused by the variation in definitions - some say the closest point at which infinity is in focus and others say the point in the middle of closest focus and infinity.
Are these the same thing?
What has shocked me is using the DOF calculator shows how small the DOF is when focusing on a relatively close object. I am going to have to find an exposure combination that gives me the sharpness I want on the subject together with the bokeh I want in the background!
The depth of field exists in front of and behind the point of focus ....typically 1/3 in front and 2/3 behind. So the considered wisdom is to focus 1/3 into the subject. In my experience it's not as precise as that and you still need to be careful you don't 'focus crop' key elements at the front or rear of the subject....that you WANT in focus. Then there is the fact that some lenses front or back focus....that's why later camera bodies have the feature to fine adjust lens focus position!
I prefer to use longer lenses for a subject and stand further back. I've never actually compared dof figures to see if it is better than a shorter lens up close ...but I just seemed to have more control of the zone of sharpness by doing that.
Changing my wording on hyperfocal distance.....it is the point at which you focus on to get the greatest depth of field which extends from infinity back to a point nearest you. In other words the focus WILL extend in front of the hyperfocal focus point by an amount ....but NOT 1/3 V 2/3 as mentioned (....or everything in front of you AND BEHIND YOU to a total distance of 1/2 infinity would be in focus.
)It's a way of ensuring any spare foreground depth of field is used up so that everything from close to you to the far distance is sharp.
Hope that hasn't confused you ....it has me.
This puts it more succinctly.....
“The hyperfocal distance is the closest distance at which a lens can be focused while keeping objects at infinity acceptably sharp. When the lens is focused at this distance, all objects at distances from half of the hyperfocal distance out to infinity will be acceptably sharp.â€
And it proves the point that the proportion of foreground sharpness varies, as in this case it is not 1/3 of the dof, like 'normal' photography ...but reaches forward only half way between the focus point and the camera.
Last edited on Wed Feb 13th, 2019 06:20 by Eric
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Eric