Depth of Field calculators

[TonyMM]

Anybody have any experience using one of the DOF calculators for iPhone/iPad ?  Such as the "Simple DOF Calculator" or "Depth of Field calculator" in the iTunes App Store ?  I know I can manually preview DOF in camera, but it would be nice to review a calculated field prior to selecting lens and/or apertures.....

Also, I assume I have to convert the focal length of a lens on my APS-C camera to the effective length when inputting data to a calculator (such as inputting 80mm as focal length for a 50mm lens on a 1.6 crop factor camera)?

Thanks for any comments/opinions.

[neuroanatomist]

I use the free Field Tools app, works well.  I also use Photo Aide ($2), which does FoV calculations (and others) in addition to DoF. 

[Marsu42]

but it would be nice to review a calculated field prior to selecting lens and/or apertures.....

Use Magic Lantern, it tells you the dof and the hyperfocal distance - and it has focus stacking if you think the dof isn't big enough at sharp apertures.

[paul13walnut5]

I use simpleDOF, which lets you select body and lens.

The information is only reasonable use and even then with certain lenses.  Don't become over reliant on it, read up on the circle of confusion for a broader understanding of whats at work.  Unless you are shooting static subjects and have very precise lens markings there's not a hell of a lot you can do with it.

You know that zooming in gives you less DOF and zooming out gives you more, you know that small aperture numbers give you less DOF and big numbers give you more. 

Half hyperfocal et al isn't really worth much to you with the seriously crappy scales even the best canon EF lenses have.  Maybe you need to look at the C line lenses!

[neuroanatomist]

I assume I have to convert the focal length of a lens on my APS-C camera to the effective length when inputting data to a calculator (such as inputting 80mm as focal length for a 50mm lens on a 1.6 crop factor camera)?

Most of the tools (including the ones I linked), you select the camera you're using.  In that case, you don't 'convert' the focal length, you use the actual focal length of the lens.

[TonyMM]

Thanks, Neuro - i've picked up a lot from your many educational contributions to this forum.  I value your input.