Hyperfocal Distance

Back to one of my favorite topics: sharpness. I have been doing some editing of old RAW captures and noticed that they are not as sharp as I would like them to be. Some of that can be chalked up to the quality of the lens I used at the time and also maybe to not using mirror lock-up, etc. But, the more I look at them the more it seems that I just wasn't focusing in the right place.

A given hyperfocal distance is the appropriate distance for focusing in order to get sharpness within an acceptable range. It is a concept that I don't fully understand and may have mis-defined in the sentence above. Here is a link to Wikipedia's definition. The point is, is that if you want a photo to be sharp from front to back, you need to focus in the appropriate place in the image.

Calculating the appropriate hyperfocal distance each shot can be challenging, as it is based on the focal legnth you are shooting at, the depth of field, and some camera specific info. I found a site here that has an online hyperfocal distance calculator that finds the appropriate distance given your situation. Also, since I always use the same camera and often shoot at similar focal distances and depths of field, I used the following formula in MS Excel to calculate likely hyperfocal distances and then wrote them down and keep them with my camera. The formula is:

F*F/(f*c)

where

F=focal length
f=f/stop
c=circles of confusion (different for each camera, but usually around .020 or .030 mm)

All units are in mm and the output will be in mm, so divide by 1000 to get meters.

I won't have a chance to go out and try this for a few weeks, but I am looking forward to getting photos with better sharpness throughout.