Camera Labs

I just got this lens yesterday and let me say it is great, what a lens, and it is sharp through all arpetures, i tested my sigma 17-70 at 70mm with the 70-300 at 70 and the canon was sharper only at f/8 the sigma was as sharp, any way i am really thinking of selling the 17-70 and buying the 17-85 IS, is the 17-85 sharp at all arpetures

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Canon 5D II, EF 24-105 f4 L IS, EF 16-35 2.8 L, EF 100 2.8 L IS Macro, EF 70-200 2.8 IS L II, Canon S90, Canon speedLight 580 EX II LowePro Sling Bag 302 AW, Photoshop CS5 Extended, Paint Shop Pro X3.

http://www.pbase.com/spartanwarrior

Hi Spartan Warrior, once youve got some good sample shots, please do a user review of this lens!

Make sure you tell us exactly which lens it is though as Canon has produced several with the 70-300mm range...

Does the end section rotate when focusing?

Gordon

Hi Gordon,, well i wouldn't be that good at a user review, but i will post 6 pictures 3 with the 17-70 and 3 with the 70-300 all at 70mm, here's what my eye's see the canon seems sharper at f/ 4.5 and f/ 5.6 but at f/8 the sigma was just as sharp as also it was at f/13 but didn't need to post that,, i also see the sigma on the shot in my yard it has better color what do you think? and it is the new 70-300 that canon just released after fixing some problems they had with their older one, all in all it's a very very good lens, and the reviews say it's a hidden L well i believe it, and Gordon what about the sharpness of the 17-85 lens thanks.

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Canon 5D II, EF 24-105 f4 L IS, EF 16-35 2.8 L, EF 100 2.8 L IS Macro, EF 70-200 2.8 IS L II, Canon S90, Canon speedLight 580 EX II LowePro Sling Bag 302 AW, Photoshop CS5 Extended, Paint Shop Pro X3.

http://www.pbase.com/spartanwarrior

That's pretty interesting - are you sure the shutter speed and ISO were the same on the two shots of your yard and that the sunlight didn't change between shots? If so, then that's quite a dramtic difference in colour!

And yes, the Canon shot at f4.5 does look much sharper than the Sigma, but then you're comparing a 17-70 at 70 with a 70-300 at 70. The Sigma is going from wide angle to short tele, whereas the Canon is going from short tele to longer tele, and the latter is arguably an easier job to perform optically.

BUT the important thing you've discovered is if you wanted to shoot at 70mm, you'd be better off using your Canon zoomed-out than the Sigma zoomed-in. This kind of test is really recommended for anyone who has lenses with overlapping ranges. It's well worth doing some tests to see which model performs best at crossover points.

Nice work!

Gordon

Here are the exif on both lenses in the yard File Name Canon f5.6.JPG
Camera Model Name Canon EOS 400D DIGITAL
Shooting Date/Time 7/24/2007 2:59:36 ìì
Tv (Shutter Speed) 1/250
Av (Aperture Value) 5.6
ISO Speed 100
Image Size 1024x683
Flash Off
Color Space sRGB
File Size 526 KB File Name............................................................. File Name sigma f5.6.JPG
Camera Model Canon EOS 400D DIGITAL
Shooting Date/Time 7/24/2007 2:57:11 ìì
Tv( Shutter Speed ) 1/400
Av( Aperture Value ) 5.6
ISO Speed 100
Image Size 1024x683
Flash Off
Parameters Settings
File Size 476 KB the sigma shutter speed was at 1/400, and the canon at 1/250, but both at ISO 100. Oh and as you see on the time the sigma lens was shot 2 minutes before the canon lens so the sun was the same,, and your not telling me anything about the 17-85 IS lol,,

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Canon 5D II, EF 24-105 f4 L IS, EF 16-35 2.8 L, EF 100 2.8 L IS Macro, EF 70-200 2.8 IS L II, Canon S90, Canon speedLight 580 EX II LowePro Sling Bag 302 AW, Photoshop CS5 Extended, Paint Shop Pro X3.

http://www.pbase.com/spartanwarrior

So the Sigma pic is the top one, which is probably the "better" exposure?

Gordon, that is consistent with my experience with the 17-70 on my 400D (when I still had it!). It tended to slightly underexpose but without going off the left wall on the histogram. I did not mind that at all as it preserved highlights, a real issue in tropical light a lot of the time.

I endorse your comments about which is better at 70mm and the overlapping test.

Cheers

Bernard