Joel:

First, I would like to thank you for always including you camera, lens, and settings data when you post.

I was noticing you still switch a lot between your 1D X and 1D IV. If you use the 1D X you typically use a 1.4X (forced to f/5.6) and the ISO is bumped a stop to a one and a half stops presumably to make up for the loss of light with the one stop loss with the 1.4X. With the 1D IV you get the reach without the tel extender so you do not loose the aperture value, but you still stop down to f/5.6 typically. So I was wondering:

  • What drives you to pick up one camera over another? Since you use the same aperture value, is it the ambient light values that drive your decision (better ISO performance on the 1D X)?
  • Is the IQ actually better with the 1D IV w/o the Tele Extender compared to the 1D X w/ Tel Extender
  • Why don't you use f/4 with your 1D IV? Is it strictly DOF... but the DOF calculator does not show a huge difference between f/4 (1D IV @500mm) and f/5.6 (1D X @ 720mm... no 700mm in the DOF Calculator and I was to lazy to do the math myself) at 10 ft stand off.


I hope you do not mind the sill questions. But I was curious why you use one over the other.

Disclaimer: The numbers I reference above are just from recent post... so I may have over simplified your thought processes - If I did, then I am sorry.

Pat