Depth of field with HTS adapter

[jonathan.lipkin]

Hey everyone - been looking around but haven't been able to find a definitive answer. I'm using an HTS adapter on a H3Dii-39. If I mount a 50mm lens, for an effective focal lenght of 75mm, how does that affect the DOF? My guess is that it would simply follow the guidelines for a 75mm lens, and I could calculate using dof master or similar using a COC of 50 microns. Or I could do some tests - is the best way to evaluate them simply on screen at 100% or 50% magnification? I'm travelling and don't have access to a printer here.

[David Grover / Capture One]

Hey everyone - been looking around but haven't been able to find a definitive answer. I'm using an HTS adapter on a H3Dii-39. If I mount a 50mm lens, for an effective focal lenght of 75mm, how does that affect the DOF? My guess is that it would simply follow the guidelines for a 75mm lens, and I could calculate using dof master or similar using a COC of 50 microns. Or I could do some tests - is the best way to evaluate them simply on screen at 100% or 50% magnification? I'm travelling and don't have access to a printer here.

I think your best bet would be to go out and shoot!

Also, you can easily manipulate the Depth of Field with the tilt function.  So probably not even possible to reliably calculate.

David

[jonathan.lipkin]

Ha! Yes, of course, have been out shooting. Calculating DOF for tilted lens plane is pretty complicated, though described well here:  http://www.trenholm.org/hmmerk/download.html.

I use the HTS as a way to shoot with longer focal length lenses without having to invest in an 80, for example. Was thinking that I might be able to do much of my shooting without tilt, or at least have a good starting point to calculate hyperfocal distance.