Lens for dog agility / action

[DavidEccleston]

Dave, all I have to go on are the ISO crops, and limited experience. While the center is sharp, the mid frame and corners are blurry.

We sold our 24-105mm f/4L as it couldn't consistently put out a sharp image on a crop body, and it's long end ISO crop images look to be a similar softness to the 70-200mm f/4L USM. If the ISO charts are soft on a 10MP 40D, so they'd seem even softer on an 18MP 7D (yes, I know, not for an equivalent sized print). I know from the 24-105mm that this softness is obvious in high contrast black and white in bright light situations, such as the ISO chart. As we have a black and white dog, and she'll be running in bright sunlight, I'm expecting this same softness to be a real world concern, just as it was with the 24-105mm.

As a real-world sanity check though, I will search the flickr pool and see what I can find.

[Busted Knuckles]

And even more here:
(a beat up old 300D with an 18-55mm kit lens will focus faster on a contrasty starburst focus target than 1D IV with 400/2.8 II will focus on an elephant in the fog at twilight).

I have no dog in this debate (grin) just thought Neuro's comment was worth a second telling for the humor.

[Dave Throgmartin]

Good point! I take you at your word. My only thought was that test charts... well, they're test charts and real world subject matter may not be quite as demanding. Black and white dogs may be though

Dave

Dave, all I have to go on are the ISO crops, and limited experience. While the center is sharp, the mid frame and corners are blurry.

We sold our 24-105mm f/4L as it couldn't consistently put out a sharp image on a crop body, and it's long end ISO crop images look to be a similar softness to the 70-200mm f/4L USM. If the ISO charts are soft on a 10MP 40D, so they'd seem even softer on an 18MP 7D (yes, I know, not for an equivalent sized print). I know from the 24-105mm that this softness is obvious in high contrast black and white in bright light situations, such as the ISO chart. As we have a black and white dog, and she'll be running in bright sunlight, I'm expecting this same softness to be a real world concern, just as it was with the 24-105mm.

As a real-world sanity check though, I will search the flickr pool and see what I can find.

[DavidEccleston]

Well, the 70-300mm f/4-5.6L IS USM is ordered. The sale at Aden ends today, and it would jump by $350 after taxes if I waited any longer.

The 70-200mm f/4L IS USM vs the 70-300mm isn't an easy choice. The "it's f/5.6 at the long end" argument is mostly silly, since it's only f/5.6 well past 200mm. The major valid argument is that it's 2/3 of a stop slower as you near 200mm. But something clicked earlier today. I imagined all the 70-200mm owners saying "But I take 80% of my shots at 200mm!". So I should opt for the faster aperture at 200mm, right? What clicked was that pushing against 200mm all the time means that all these people really wished their lens went PAST 200mm.

Thanks to everyone who replied. I'll be sure to post some pics when the new glass arrives.

[andnowimbroke]

HD wins the pool. Hope he got his money in on time.

[Dave Throgmartin]

I rented the 70-300L last year and found it to be an excellent general purpose lens. Best of luck with the new purchase.

Dave

[Sheiky]

What clicked was that pushing against 200mm all the time means that all these people really wished their lens went PAST 200mm.

Great reasoning! I hope you like the new lens, but I'm pretty sure you will. I'll be tuned in for the first results
I hope you won't make too much shots at 300mm though...you might want to switch to the 100-400

[DavidEccleston]

After waiting forever for it to arrive, the 70-300L did indeed arrive on Friday.

It focuses fast! It's nice and long! It's super sharp! DPP's new DLO makes it even sharper! The wife finds it too heavy.

Agility comes tomorrow... but first, a few test shots (the horses look better in Flickr's lightbox mode than on harsh white).


Horse taking a break by namethatnobodyelsetook, on Flickr


Jousting by namethatnobodyelsetook, on Flickr


Jousting by namethatnobodyelsetook, on Flickr


Chipmunk by namethatnobodyelsetook, on Flickr


Deer by namethatnobodyelsetook, on Flickr

[conropl]

After waiting forever for it to arrive, the 70-300L did indeed arrive on Friday.

It focuses fast! It's nice and long! It's super sharp! DPP's new DLO makes it even sharper! The wife finds it too heavy.

Agility comes tomorrow... but first, a few test shots (the horses look better in Flickr's lightbox mode than on harsh white).

Congratulations on the new lens. The sample shots look great. It seemed to work well keeping a running horse in focus. Also, the deer is real sharp even though there is plenty of objects around the deer to confuse the focus (e.g., grass, trees..). If your keeper rate was good, then it looks like it is a lens that should work well for your purposes.

[thekingb]

Congrats! During the "outdoor" months, it is my most used lens. I have zero complaints given its specs. Some people complain that's it's a slow lens with a variable aperture. Well, that's how Canon packed a 70-300mm range into a relatively compact and "light" lens with excellent IQ! Your keeper rate will be very high. Enjoy!