Depth of field

[hueyatl1]

Is there a gain in Depth-of-field(DOF) in using a wide angle lens if the aspect ratio is return to 1:1?

ex: a 50mm lens @ f8 has DOF from 12'-infinity and a 28mm @ f8 has a DOF from 5'-infinity. So the question that am asking is: want is the DOF a 28mm with 2x optical zoom? Would it be 12'-infinity, 5'-infinity or something in the middle?

 

[cdiver2]

See if this helps
http://www.dudak.baka.com/dofcalc.html

 

[MarkH]

Is there a gain in Depth-of-field(DOF) in using a wide angle lens if the aspect ratio is return to 1:1?

ex: a 50mm lens @ f8 has DOF from 12'-infinity and a 28mm @ f8 has a DOF from 5'-infinity. So the question that am asking is: want is the DOF a 28mm with 2x optical zoom? Would it be 12'-infinity, 5'-infinity or something in the middle?

A 28mm lens is a 28mm lens. As far as I know, there is no such thing as a 28mm zoom. You may have a 28-70mm zoom lens (as an example). There may be some digitals or point and shoots that advertise a 28mm lens with a 2x optical zoom, but as soon as you press the zoom button it is no longer a 28mm lens, but something longer. You can take a 28mm lens and add a 2x teleconverter (Is that what you mean?). As soon as you add this, it is no longer a 28mm lens either. I may be making this up. Maybe someone else can explain it better.