CANON EOS 40D FULL REVIEW PARTII

Highlight Tone Priority a new feature in the EOS 40D


.......This is a new feature in the EOS 40D . As the term suggests, it is supposed to preserve highlight detail better. According to the information in the instruction manual, enabling this feature “Improves the highlight detail. The dynamic range is expanded from the standard 18% gray to bright highlights. The gradation between between the grays and highlights becomes smoother.”
To enable this feature, you have to set make the setting in the EOS 40D custom menu.

EOS 40D With Highlight Tone Priority enabled, the ISO setting will be limited to 200-1600. ISO 100 and 3200 will not be available.
I have made some shots to test out this new feature. the following shot was shot with Highlight Tone Priority disabled, the subsequent shot was shot with Highlight Tone Priority enabled.

EOS 40D out this new feature

EOS 40D shot with Highlight Tone Priority enabledI can see a subtle increase in detail in the clouds in the second photo. I have taken other test shots for which I could not detect any difference between the photo with this feature enabled and the one without. For the moment, I have to say the effect of Highlight Tone Priority is subtle at best and the effect can quite easily to achieved during post-processing. However, I will reserve judgment until I have time to test out this feature more thoroughly.
Autofocus in EOS 40D
Probably due to the fact that all 9 autofocus sensors are cross-type sensors in the EOS 40D D, autofocus with the peripheral sensors have much improved over the 20D/30D especially under low-light low or low contrast situation. Previously, with the 20D, it was very difficult to get the focus to lock on with the peripheral sensors under lowlight or low contrast scenes. The focusing would hunt quite a bit before being able to find a focus, sometimes, it would be impossible to focus with the peripheral sensors at all. With the 40D, all the peripheral sensors locked on focus almost instantly even under low light or low contrast scenes.
I have tested out the focus tracking using EOS 40D AI Servo mode and found the focus tracking to be good.
The following are 2 test sequences using EOS 40D AI servo. The first sequence showed tracking of bicycle.

High ISO 100% crop comparison
Due to many requests for 100% crop comparsion between the 2 cameras at high ISO, I have added this section. I have done 100% crops for ISO 800 to 3200. 20D crops are on the left side and EOS 40D crops are on the right side

ISO 800
ISO 1600

ISO 3200
............................................................... EOS 40D review by http://rolandlem.wordpress.com

Canon EOS 40D video review