Understanding Sekonic L-758DR Camera Exposure Profiles

I’ve owned a Sekonic L-758DR for the past three years, and until recently, had not successfully created a camera exposure profile for any of my camera bodies.  I’d like to say that I tried and tried to no avail, but that was not the case.  I tried a couple times using the eleven stop method and just never managed to get it right. 

Recently I watched a Sekonic webinar, hosted by Joe Brady, that covered how to get better exposures on landscape photos using a Sekonic lightmeter.  During the webinar Joe mentioned exposure profiles for the L-758DR and how to use custom functions with the L-758DR to take advantage of the information provided by the profile. This spurred me to review Sekonic’s latest software release and try again.

Sekonic’s latest software release, DTS 3.0 is simpler to use and can create a profile from three images taken three stops apart, provided you have the Sekonic Exposure Profile Target II.

Here’s where it gets interesting.   I created exposure profiles for a Canon 1Ds mk II, 1D mk IV, and 1Ds mk III.  For each profile the dynamic range shown by the DTS 3 software was between 5.9 and 6.1 EV (stops), while the max dynamic range reported by DXOmark for these camera sensors varies from 11.3 EV for the 1DsmkII to 12 EV for both the 1DsmkIII and the 1DmkIV. 

I tested some of the information that Joe presented during the webinar and found it to work well with the L-758DR.  I also emailed Sekonic and asked about the discrepancy in the dynamic range reported by their DTS 3 program and the data published by DXOmark.  I’m still waiting to hear from Sekonic and I’m not holding my breath while I do so.

We can only hope that Sekonic will step up and explain the profile created by their software.