Unsharp images using Canon 350D

[Fairyan]

At a sunny day i made some foto's with my Canon 350D (and my Tamron SP AF 28-75mm f/2.8 XR Di LD Asp. ). I used iso 100 and the daylight WB-setting. I like the background to be unsharp so I used f2.8. I used auto focus and focussed at the middle focus point(pressed the shutter-release button half). The middle focus point went red and was at peacocks head. I changed the frame a little bit while keeping the shutter-release button half pressed, then pressed the shutter-release button full to make the photo.

With 1/620s exposure time it must be sharp but it appears to be out of focus.
http://www.ryanne.nl/IMG_pauw.JPG
The same thing happenend with most of my other photo's for example the one with the girl. http://www.ryanne.nl/IMG_gezicht.JPG

Camera settings:
iso :100
f-number: f/2.8
Exposure time: 1/620 s
Focal Lengt: 75 mm
White balance: daylight
exposure: auto exposure
no flash used
Lens used: Tamron SP AF 28-75mm f/2.8 XR Di LD Aspherical (IF)

Do you have any idea what went wrong?

[PhotosGuy]

Could be that you moved.Could be a cam/lens problem. 2.8 DOF is very small, so I'd suggest a test. Put the cam on a tripod & focus on something about the same distance away @ 75mm f/2.8 & take a shot. See what you get.

[SeanH]

Looks like camera shake to me. If you just missed the focus there would be some part of the frame in focus. But I'm calling camera shake.

[malcolmx]

birds move at a very fast rate their reaction times are miles quicker than ours and i suggest that the bird moved between the time you applied focus lock and actualy took the shot . focus lock only locks focus along the plane of the focus at the the time of the lock

[PhotosGuy]

Looks like camera shake to me. If you just missed the focus there would be some part of the frame in focus. But I'm calling camera shake. Don't you think he'd notice if it was that bad at 1/620 sec?

[ecobo]

Try with another lens. This looks like a lens' fault.
Try also with smaller aperture - low-end lenses do not perform well wide-open.

[Andy_T]

My pictures with the Tamron 28-75/2.8 XR definitely don't look like that at f/2.8 :shock:
Here (http://photography-on-the.net/forum/showthread.php?t=67200&highlight=tamron) are some other examples from various users.

Maybe it's time to put the camera on a tripod and take some test shots ... like in this thread (http://photography-on-the.net/forum/showthread.php?t=51644&highlight=tamron).

Best regards,
Andy

[CyberPet]

I'm on my third Tamron 28-75/2.8. The first one had problems with serious front focus and was *blurry* (not soft, mind you) at 28 mm @ f/2.8. The second lens had the opposite problem, it was sharp at 28 mm wide open, but if you zoomed in, you got blurry image. Sent that lens back too. The third lens has a bit of a front focus problem in AF, while in MF it focues correctly, so I'm keeping it and will send it in for calibration.

The second lens I had reminds me so much about the results you got on those shots of the peacock and the girl. It was totally useless in 75 mm!! (even if you used f/8.0 you didn't get decend sharpness).

[Fairyan]

I think i know what the problem is: DOF miskalculation. Because I was only 1,5 meters away from the subject at f/2.8 the DOF was less then an inch. While I focussed and recomposed the chance of getting ut of the small focus range is very big.

I tried the same thing @75mm, 2 meter from subject but used f/5.6 instead of f/2.8. The photo are much sharper.

http://www.ryanne.nl/michel_test.jpg

thank you for your replies & tips

[Fairyan]

hi Cyberpet,

you mentioned calibration of the lens. Will that make a difference when there is not a major lens fault? I mean It looks like it is ok. But whem it will even be better after calibrating then I want that too.

I bought my lens in Germany (online shop) and I live in the Netherlands. So going back to the shop is not really an option for me.

Can I callibrate my lens myself or should I bring it to a photo shop?

[Duncreavy]

cyberpet--where/how do you send a lens for calibration? thanks.

[CyberPet]

I have no idea about how the lens will perform after the calibration, but I asume it'll perform better than it does now, since the AF is off. A neighbor of mine has the same lens and his lens works fine in all ranges and all apertures, so I assume I hope mine will perform like his once it gets back.

Since Tamron doesn't have any service here in Sweden, my lens is going to be sent to Germany. The store (online) that I bought it from here in Sweden are paying for the shipping, since it's within warranty and they've more less tested every lens they have in stock to find me a working one. This third one was the best we could find (and this was not just me thinking the lens was faulty, they were agreeing, hence they are going to pay for everything).

The problem is that I would have sent the lens away as soon as possible, but in 1.5 weeks I have to use my camera (and lens - in MF) for a wedding shoot I've promised. After that I could have sent it away, since my next "gig" is in july 9th, but the turnaround time for the calibration is said to be 6-8 weeks, so I don't want to risk those small margins, so I'll send the lens in after my gig in july. Then I should hopefully also have a nice 20-35/2.8 L lens to play with, so I won't miss that 28-75 mm range too much (I'll have to zoom with my legs then).

[Fairyan]

CyberPet. You should consider the Tamron 17-35mm f/2.8-4. It is great and really very sharp at all apertures. It is cheap and very good and very sharp according to many reviewers. And more wide angle then the 20-35mm L.

Picture of tamron 17-35mm box is taken at 17mm at f/2.8 (100% crop, no post processing and no sharpening, only a lot of jpg compression to keep under 100kb, so it is even better uncompressed)

reviews:
http://www.fredmiranda.com/reviews/showproduct.php?product=191&sort=7&cat=43&page=1

[CyberPet]

Fairyan, thanks for your suggestion! I am however pretty set on the Canon 20-35/2.8 L that my friend is selling to me later this year. It's at a price I can't say no.... and I have a soft spot for thoe f/2.8 lenses through the whole zoom range. :D