Depth-of-Field on DX lens

danster · 7th March 2005

Just wondering whether the DOF for DX lens is equivalent to the actual focal lenght or their 35mm equivalent field of view?

For example, for the 18-70mm D70 kits lens, is the DOF at 18mm equivalent to that of an 18mm lens or that of a 28mm lens? My guess is that it should be that of an 18mm lens but please correct me if I'm wrong.

Apologies if this question has been asked before.

Thanks in advance.

mpenza · 7th March 2005

There were some discussions on this and references to DOF calculator. but if you're not really into the calculations, DSLR with crop factor will have deeper depth of field for a lens that has the same "equivalent field of view" on a film SLR. it's the same whether the lens is DX or non-DX.

user111 · 7th March 2005

to give some concrete examples:

the same scene for 18-70DX on dslr, shot @ f5.6,

will look roughtly like

28mm on film body, shot @ f8.

7th March 2005	#1
danster Member Join Date: Oct 2003 Posts: 580	Depth-of-Field on DX lens Just wondering whether the DOF for DX lens is equivalent to the actual focal lenght or their 35mm equivalent field of view? For example, for the 18-70mm D70 kits lens, is the DOF at 18mm equivalent to that of an 18mm lens or that of a 28mm lens? My guess is that it should be that of an 18mm lens but please correct me if I'm wrong. Apologies if this question has been asked before. Thanks in advance.

7th March 2005	#2
mpenza Moderator Join Date: Jan 2002 Location: New York City Posts: 13,397	There were some discussions on this and references to DOF calculator. but if you're not really into the calculations, DSLR with crop factor will have deeper depth of field for a lens that has the same "equivalent field of view" on a film SLR. it's the same whether the lens is DX or non-DX.

7th March 2005	#3
user111 Senior Member Join Date: Jul 2004 Posts: 4,719	to give some concrete examples: the same scene for 18-70DX on dslr, shot @ f5.6, will look roughtly like 28mm on film body, shot @ f8.