What is Depth of Field?

Maks is continuing to amaze us with his serious work with portrait lighting.  He made reference to his new lens and the "bokeh" it can make.  The issue is the wider the aperture of the lens, the more easily objects in front of and in back of the lens can go out of focus. His new 85mm 1.8 is just such a lens.  1.8 means the diameter of the glass is much wider than the average "kit" lens that comes with a DSLR.  It is more expensive to make...In the days before digital photography, oftentimes the goal was the opposite... to have very deep depth of field or depth of focus by stopping down the aperture on a lens all the way for landscape shots.

Now with small sensors on point and shoot cameras and phone cameras, everything is in focus all the time and the goal is to be able to throw the background out of focus.

Here is a family snapshot from last night of our 1 year old Golden Retriever, Emma.  See how the lights of the tree behind her are thrown out of focus?  I used my 50mm f 1.4 lens wide open (at 1.4) and I have a full frame sensor on my camera, causing the depth of field to be even narrower.

This was taken in "RAW" mode for better control over exposure and color balance under the very warm room lights at night.  The camera is a Nikon D800 which has a sensor the size of a 35mm negative and a 36 mp sensor to boot for amazing detail.

All of this tech talk is for those wanting to move beyond the beginner stage...Maks has done a great job with his Digital II project...