105 or 60

[Doc Harry]

The question is not, "What's the difference in DOF between a 60 and and 105 lens?"

The question is, "What's the difference in DOF between a 90 and and 105 lens?"

According to you chart, at f/32 and 0.5 feet the DOF is as follows:

60mm DOF = 0.49 to 0.51 feet

105mm DOF = 0.50 to 0.50 feet

I assume that DOF differences between 90 and 105mm lenses are nill.

[WetLens]

Online Depth of Field Calculator	90	105
Subject distance	12 in	12 in
Depth of field
Near limit	11.9 in	11.9 in
Far limit	12.1 in	12.1 in
Total	0.2 in	0.14 in
In front of subject	0.1 in (50%)	0.07 in (50%)
Behind subject	0.1 in (50%)	0.07 in (50%)
Hyperfocal distance	1000.1 in	1360.6 in
Circle of confusion	0.02 mm	0.02 mm

[Meyr]

Online Depth of Field Calculator	90	105
Subject distance	12 in	12 in
Depth of field
Near limit	11.9 in	11.9 in
Far limit	12.1 in	12.1 in
Total	0.2 in	0.14 in
In front of subject	0.1 in (50%)	0.07 in (50%)
Behind subject	0.1 in (50%)	0.07 in (50%)
Hyperfocal distance	1000.1 in	1360.6 in
Circle of confusion	0.02 mm	0.02 mm

so what does the numbers mean?

[WetLens]

Not much. Question was asked; answer provided. Bottom line is that there is a trade-off between lenses and understanding those trade-offs and what you want to accomplish should guide your lens decision. Want more DOF, choose a shorter focal length lens and/or close the aperture; want less DOF, choose a longer focal length lens and/or open the aperture. If DOF isn't the concern, decide what is - understand the differences between lenses and choose appropriately. There is not one answer to the question, "Which lens?"