能否幫我判斷這樣是否準焦

blackwheel wrote:
之前遇到60D+si...(恕刪)</blockquote

Well, I looked really carefully into the picture you show to us. I think it is back focused too.

If you look carefully, the DOF is not centered at 0 but at -0.5~-1.

This lens has one interesting characteristc defect. I guess you can try it at home too.

1. When the object being shot is 3 meters from your camara then it will back focus about 3 inches.
2. When it is super accurate and focus dead center at F1.4 at minimum focus distance, it will back focus at F2.8~F4 at minimum focus distance.


I myself is an owner of Sigma50mmF1.4 and I have to say I give up tunning already..... although it is a good lens. I kindda feel embarassed to go to Sigma Taiwan again. I have asked the Sigma engineer to adjust my S50mmF1.4 five times already....

One thing interesting, the more I ask engineer to adjust my s50mmf1.4 the more it becomes less sharp.... I even start to doubt maybe the motor on my S50mmf1.4 is not working properly... Now, my EF 50mmF1.8 Mk II is sharper than S50mmF1.4 at F1.8.

Another interesting thing is all my canon friends love to borrw this lens from me. Guess what? I am more than happy to lend them to use that lens. hahaha.

Anyway...

Cheers and have a nice day