Is My 70-300 DO IS USM Too Soft?

I've owned this lens for a few months now and can't make my mind up as to whether or not it's too soft.

I find it quite a frustrating lens - sometimes it can bring out excellent shots, others they're just too soft. It's saving grace is its relative small size and weight which are ideal for when I take it travelling.

Attached are a couple of resized examples, both taken with the aid of a tripod (even when set in IS Mode 1).

The jpeg's taken straight out of the camera are HERE and HERE (WARNING: 1mb+ files).

Each shot was taken with my 20D in AV mode, set at ISO200, -0.67 EV, and at 200mm. No filter was attached.

Any thoughts/comments would be appreciated

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First, turn OFF IS when using a tripod. You can get feedback from the IS which makes things worse. My 70-200 IS' manual says it recognizes when a tripod's in use, but it still recommends turning IS off when using one.

Second - how about some 100% crops of the focus point rather than resized full frame shots?

Can't be that soft as I can make out the spiders web on the left of the pole. Taken at 1/125 at 5.6 I should say they may be a little soft, but would be perhaps better at f8 or greater?

I usually do turn IS off when attached to the tripod, but for this I wanted to see if there was much of a difference using exactly the same circumstances. That is, until I noticed upon returning to the computer that I must have knocked the tripod as the images are not the same

The larger images posted HERE and HERE are straight out of the camera (using high quality medium JPEG setting) and not resized on the computer. I don't have access to the RAW's but will do so when I get home.

Thanks for the advice

Looking at the larger images, the camera certainly had enough choices of what to focus on.I think it focussed on one of the wires, which would put everything behind it, including the post, a little out of focus.

The camera was aimed to centre focus on the knot of wood in the post.

The area actually covered by the AF sensor doesn't correspond exactly to the area delimited on your focussing screen. The AF sensors are located on the bottom of the mirror box, while the markers are actually up on the screen. So the area covered may be slightly larger than is marked, and if the screen is a little out of alignment, there will be still further difference in the zone focussed on. Also, the AF will lock in on the contrastiest object there, and that black wire's showing more contrast than the knot.

Looks good to me, I'd say start finding better things to take a picture of then a telephone pole on a cloudy day

That lens looks plenty sharp to me.

Actually looks like a ver good copy of 70-300 DO IS Lens

AndyM.
I own this lens as my personal travel knock-about while using the L lenses at work, so I'll offer my opinion.
1. From the looks of this photo, you have a VERY solid sharp copy of this lens.
2. You are shooting a low contrast subject on a day with obvious atmospheric moisture further degrading contrast. Call it haze, vapor, cloudy, whatever. But real world nature-objects we see in our environment-are not "sharply defined" under atmospheric haze.
You might have done better by boosting Contrast Slider in PSCS ACR RAW to, say 52+/- under this atmosphere.
You can easily see that this is a low contrast photo condition by looking at the "narrowed" histogram in PhotoShop. And in photographs contrast = sharpness. Would L glass have done better? Yes, but not by much under these conditions.
3. You are shooting a telezoom wide open. No f/5.6 telezoom shot wide open displays its best. This photo isn't bad considering. The 70-300 DO IS gets much better stopped down just 1/3 of a stop. It really gets good at f/8.
4. All 70-300 DO IS owners need to learn "edge sharpening" in PS to get the best from this lens. See my user experience with this lens on edge sharpening here. Step through images and read the captions.
http://aesop.rutgers.e​du …0DO%20IS%20Lens​/index.htm
5. You are shooting a DO lens, with its fresnel lens, at a subject where the out-of-focus background contains repeating fine details (brick work building). It's the kiss of death for this lens. Don't do that.

I took your image, and did a 5-second contrast adjust in Levels to pull the histogram down to get some blacks, the then edge sharpened it. Here is a 100% crop that shows how sharp your photo is. Wire and wood details damn good considering the above!:
http://postit.rutgers.​edu …/Contrast%5FSha​rpen%2Ejpg

Jack

My experiences are similar to Jack's in the post above. The 70-300DO begs for a little bit of sharpening and some contrast adjustment when shot wide-open. Shooting a dull object on a cloudy day adds to this need. And as noted, contrast plays a great role in percieved sharpness. Lock at Jack's improved 100% crop in the previous post.

Stopping down 1/3-2/3 stops really makes a big difference on my copy of the DO.

Thanks for the pointers guys, very much appreciated.

Jack - I'll keep in mind your advice, especially regarding the repeating details. I looked at your photo guide and can see exactly what you are referring to, though, my picture doesn't appear to suffer quite so badly as your soccer dad example.

Again, thank you very much for the advice

They look just fine to me. Keep in mind, that's not exactly the sharpest thing out. Also, it's a zoom. Can't expect that prime sharpness. However, a little USM, and I think they'd look just fine and dandy.