Focusing test - 40d 400F5.6, 40d 300f4

[tzanampeths]

What is your impression on the attached photos?

From left
400f5.6 @ f5.6, 400f5.6 @ f8, 300f4 @ f8, 300f4 @ f5.6, 300f4 @ f4

On a tripod with self timer. I've superimposed the AF sensor, 100% crops.
PP:
Exposure +1.5, Clarity +10 in ACR, no sharpening.

Tnx in advance

Takis

By the way what does clarity do? It seems to me it enhances contrast/edges somehow, something like a High radius low amount USM effect

[JohnZ]

Have you got a shaky tripod ?..............LOL

[tzanampeths]

Have you got a shaky tripod ?..............LOL

Actually John it's a Manfotto 055xbk with 501hdv head... Wouldn' call that shaky

[stu78]

I am not really sure what you are asking here. Your results do look a little out of focus in my opinion, maybe a ruler is not the best subject for a test. The two lenses you are comparing are both known to be fantastic performers, tho I am surprised that the 300 seems sharper stopped down. I thought this lens was supposed to be pin-sharp wide open.

I find that for pixel peeping tests the free program called Firestone Image Browser is ideal as it allows you to see the shots side by side on the screen.

I did a similar test to compare my 400mm f5.6 L with my old Sigma 70-300 Apo DG and unsurprisingly the difference between the lenses was immense. I've attached my results (100% crops) of the crude test I performed with the Sigma on top and the Canon below. On the left is f5.6 and on the right is f8. I took 3 shots with each lens at each setting, allowing the camera to refocus between each shot, and picked the best one of the 3 shots. All shots were taken with a 400D using standard picture style so there is a little in-camera sharpening.
Anyone upgrading to a Canon 400mm f5.6 from any 70-300 zoom will be amazed by the Canon L quality.

Stu

[tzanampeths]

I am not really sure what you are asking here. ...
Stu

Hi Stu,

I wasn't pleased with the sharpness I was getting from my camera both with the 70-200f2.8 and the 400f5.6, so I was wondering about the AF performance of the body.

So I'm trying to test the AF actually. All photos are taken with OneShot AF. The ruler was at a 45o angle to the camera, but as you've both indicated I'm not able to pinpoint the real AF point on these shots.

What would you suggest to replace the ruler with, a surface with fine print on?

Tnx
Takis

[stu78]

I'm sorry but seeing as nothing seemed to be in perfect focus I assumed you were concerned about the general sharpness. I think the lack of sharpness is due to the not-so-fine print on the ruler tho as opposed to your lens. The most in-focus point of the ruler does appear to be around the point where your camera auto-focused so maybe there is no problem at all. I would definitely try it again tho with something with much finer print. For my shot comparison I used the (very) small print on the back of a pack of rechargeable batteries at a distance of nearly 10 yards. I am sure there must be something far better that you can use tho.

Stu

[GYRob]

the 400f5.6 is sharper than the 300f4 i owned both of these lenses so know that as a fact ,
these shots are not as good as they should be thats for sure.
try manul focus, mirrow lockup, self timer to see just how sharp they are.
Then test AF with the same set up .
Rob.

[IanF]

Even the 400mm f5,6 captures do seem a bit soft.

This was taken with the 40D and same lens hand held under shade on a cloudy day! ISO400 f5,6 from around 8m.

I'd be inclined to repeat the test on another subject.

[tzanampeths]

Thanks for the advice guys.
I'll repeat with a different object, I guess something with crisp fine print.

All the best

Takis

PS. The distance was about 4meters, in house.

[Roy C]

I would be disappointed with these even if I hand held the 400 5.6.

[tzanampeths]

I guess something with crisp fine print.


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