Just when I thought it was safe to go back to the camera shop (70-300 DO)

[Asmodeus]

I really didn't think I needed any more lens, but I've got a lot of travel coming up and have been dithering about what lens/body combinations to take. I still haven't solved that problem completely, but I stopped at Allen's Cameras (my local shop, unfortunately) today to buy a small set of travel reflectors (left my last set somewhere I can't recall) and they had a just received a stock of the refurbished 70-300 DO lenses from Canon.

$899 later I think I have my walk-around lens for this summer's travails ;)

They still have 4 remaining in stock (as of about 20 minutes ago) if anyone else has the bug.

[323]

wow u got a big collection lol

[Asmodeus]

Well, after about 100 shots at various stops, ISO, and mm, the lens is going back tomorrow. It is soft across the board. The question now is simply do I try another one or give it up as a lost cause?

[JNunn]

I asked about that lens before I decided on the 70-200L. The guy at my camera shop gave me the high sign (indicating not-so-good) and steered me toward either the 70-200 f/4 (for less money, by the way), or the 300L. We took both the 70-200 and 70-300 outside and took about 20 shots each. It was NO CONTEST! The 70-300's extra reach wasn't worth much since it is pretty soft at 300mm. The idea of the extended reach in a compact lens size is great, but they didn't pull it off with this lens IMHO.

[PhotoScout]

I would say try another and if your still not satisfied, then give it up. If you keep the lens that you are not totally satisfied with, it will bug you to death. For your sanity it might be better to wait and get a brand new lens. Even if it costs more, it will give you a piece of mind. Just my thoughts.

[BigBlueDodge]

Asmodeus, what you found is actually pretty common. The one negative to the 70-300 DO is that its images are rated soft by most of its users. However, I think its to be expected. Canon had to do alot of work to get that focal range in such a small package. There are comprimises to be made, and it appears that IQ took a hit. Being small, light, and easy to carry doesn't come for free. For someone traveling, the reduction in IQ may be tolerated due to the weight savings. Plus, most people can correct it with a little USM in PS.

[Asmodeus]

I had read the reviews and was willing to tolerate softness at the long end and correctable softness or needing to stop down elsewhere. I shoot only in RAW anyway, so I figured that it wouldn't be a big deal.

But with this copy of the lens the sharpness at 100mm at F8/F11 was as bad as 300mm 5.6 which was completely unexpected. I actually went and reshot a bunch of nice stationary objects and still found that the detail was missing from the images no matter how I post processed them.

I will get another copy tomorrow and see how it does. I'm willing to make the sacrafice of the image quality that my other lenses are capable of for the convienience factor this lens represents, but not to the degree that this copy of the lens seems to require.

[GNMink]

You would think at @ $1000 or more canon would have their act together with quality control, but it seems there is alot of variation between copies of this lens.

From what I've seen posted you CAN get a good copy though

[Asmodeus]

Second copy of the lens is very sharp wide open up to about 180mm, then starts to fall off. Nothing that can't be managed in post processing.

http://www.digitalperf.com/photo/albums/userpics/10001/sharptest1000.jpg

This image is wide open at 300mm, 400 ISO, 1/256, minimal PP and an example of the bad end of the lens.

[karusel]

There is a scary lesson here...

Buy your lenses from local shops so you can try them out or else risk getting a bad copy.

I always wondered, doesn't Canon somehow actually TEST the leses they're assembling? $800 and more in not exactly peanuts, so I'd expect the lenses would work just as specified with no exceptions, unless of course some ultra rare mechanical flaw were to occur. And I don't stop hearing about how people walked into shops and tried several lenses of the same type and some are sharper than the others. What's up with that?

[Lightstream]

Ahh....every photographer needs a lightweight telezoom for all the days when you don't feel like lugging the whole shop around :confused:

I've been running flat out the whole week, I'm tired (physically too, moving a great deal of gear ranging from 20-50 pounds), I put the 70-200 Sigma in my bag to go shooting this weekend and decided heckit, I'm not bringing that monster, my shoulders want a break too :mrgreen:

The 70-300 IS USM (non-DO) is nice too, if you want to try it out. It doesn't have the DO's build quality but optical imaging performance is definitely all there. Shoot it in portrait orientation at 300mm to check for the portrait bug while you're at the shop. I was lucky - mine is supposed to be affected based on serial number, but it works fine. Now I'm gonna enjoy my weekend with a lot less lens. ;)