Is my 70-200 f4 L Lens sharp enough?

Lesjordans · Jun 28, 2006

Just making sure it is sharp enough to save me sending it back to canon, i always thought they were sharper than that.

Shot was taken at F8 200mm, on a tripod and this is a 100% crop.

Any honest advice appreciated!

Link to the pic in question http://www.deviantart.com/view/35489737/

niccig · Jun 28, 2006

That picture looks pretty soft to me. What shutter speed did you use? Did you press the button, or use the self timer? If you pressed the button, you might try using the self timer (assuming your camera has that feature) to see if motion blur from vibration is causing the problem.

Also, were you using manual or auto focus? It might just be that the picture isn't focused well. Are all your pictures turning out like this?

Lesjordans · Jun 28, 2006

yeah they are to be honest, what can i do?

Big Mike · Jun 28, 2006

Model: Canon EOS 350D DIGITAL
Shutter Speed: 1/90 second
F Number: F/8.0
Focal Length: 200 mm

I see the shutter speed was 1/90. Were you hand holding this shot?

At 200mm you should have a minimum shutter speed of 1/320 (1/200 on 35mm film or full frame digital) to prevent blur from camera shake. To get that, open the aperture and/or raise the ISO.

Of course, if the camera is on a triopd and fired with a remote or self timer...there is little or no camera shake.

Lesjordans · Jun 28, 2006

I was using a tripod and standing well away

Flash Harry · Jun 28, 2006

Sometimes with long focal lengths the operation of the shutter can cause enough vibration to distort the image even on a tripod, could your tripod be a little lightweight too, most amateurs buy tripods that are pretty useless for the job, try again with a faster SS and see what happens. If the results are garbage return the lens as the result posted was pretty mediocre.

Lesjordans · Jun 28, 2006

Thanks, I live near a Canon service centre so would i just be able to drop it off rather than post?

964 · Jun 28, 2006

Thats so soft it looks out of focus......there is a serious problem here somewhere....

Lesjordans · Jun 28, 2006

well that doesnt sound too healthy

Lesjordans · Jun 28, 2006

New Sample up, still looks a duff unfortunately http://www.deviantart.com/view/35495701/

markc · Jun 28, 2006

Does the 350D have mirror lock-up? If you have a flimsy tripod, that can be the main culprit. Try using mirror lock-up and the self-timer.

Jeff Canes · Jun 28, 2006

You should not need to use a tripod or mirror lockup to avoid softness; the lower shutter speed is a possible reason, but you’re still having the problem with the higher speed so that does not seem likely ether.

It may well be the lens but there are a few other things to look at too.
1) What resolutions and size did you shoot these in?
2) How where they resized the file?
3) What focusing mode where you using?
4) How is the sharpness with other lenses?

Lesjordans · Jun 29, 2006

Thanks for the advice folks! Results are as follows with a 100% crop of a newspaper using F4 and Mirror Lockup with Self timer

http://www.deviantart.com/view/35519111/