DSLR Photography Forum

a friend asked me this the other day....

shooting at a small F-stop (like 2.8) gives you a shallow DOP, which helps blur the background.
What would be an appropriate or at what F-stop at least would one be able to capture clarity of entire image thru view finder?

how should i answer?
I do not have a technical answer to that cause i have been shooting via feel and past experiences...

anyone?

Depends on how far away your focus spot is, and what the range of distances in your shot is. If your focus point is at infinity, amd all objects in the picture are also at infinity, even a small F number will give you clarity throughout. Assuming that you are focusing closer, and have a range of subject distances, you need to stop down to higher numbers to keep everything in focus. Many lenses have a guide on them that shows in focus depth of field at given focus points and aperatures. Take a look at yours. This seems to becoming rarer with most lenses being autofocus, but it is still present on a lot of lenses. Failing that, there are tables available online to calculate in focus depth ranges based on focusing distance and aperature setting.

Sorry to be vague - if you want a really simple answer, you say F16 and higher. That usually keeps everything in focus regardless of distance.

http://www.dofmaster.com/dofjs.html

Here is an easy way to calculate.

/Paul L.