View Full Version : 70-200 f/2.8L w/2x AMAZING results

04-20-2009, 08:51 PM
I must have an excellent combo here:

These are 100% crops of a toy salamander.
I shot the 400mm first, then removed it and recomposed to approximate the same FOV.
I sharpened at 80,.3, 0, then resized both images.
It is also worth noting that both images were shot at ISO1600!

I wonder why the DOF at 400mm would be less, despite being f/5.6 light, I thought the DOF stayed the same with a TC, just the light falloff drops the f-stop.

I wouldn't think twice about using the 2X TC now after this test.

The Sigma that I had was softer than the 2x TC version without a damned TC on!

04-20-2009, 08:56 PM
Ah, I was closer with the 200mm version so the DOF is shallower....
That explains it!

04-20-2009, 09:34 PM
Id be more curious of some shots in the iso 200 to 800 range then 1600 to be honest.

I never really look at iso 1600 if i want to judge the technical merits of something :P

04-20-2009, 09:51 PM
I did a quick test out of excitement of receiving the lens, but didn't realize I was at ISO 1600.
I'm certain sharpness will be dramatically improved at ISO 100.
I will repeat with a tripod to see the difference.
Either way, count me impressed.