Chris help new canon lense

[Cutter]

Hope you see this chris I know you know your stuff, I want to buy a wide angle canon lense that gives crisp focus, what would you go for? up to a £1000.00

I have a canon efs 17-85mm but my pictures dont seem sharp even with a tripod, shutter release and mirror lockup.
Anyone else that could give some input I would appreiciate it

[chris-p]

Hi Mark

Hmm, wideangle Canon fit lenses. I suppose you've really got 2 options, the Sigma 10-20mm is really popular and most people love it (I certainly do) or the Canon 10-22mm. Neither of which are anything near £1000 - but there isn't much in that range. Probably the sharpest wide angle would be the Canon EF 14mm f/2.8 but it's more like £2000!

I'm surprised that you can't get sharp images with the 17-85 though, how are you focusing? People tend to be a bit more sloppy with their focusing on landscape shots but, if you're after sharpness and lots of depth of field, the focusing is critical.

Also, since Flake has left it's not been mentioned that much but diffraction could be a real issue here. IIRC you've got a 50D which has a lot of pixels crammed onto it's sensor so the bottom diffraction limit is going to be pretty early on in the aperture range. What sort of aperture values have you been using, and what sort of focus settings have you used (ie, which points, AF mode or manual etc)?

[Sue Allen]

http://www.lensrentals.com/news/2010...nd-other-facts

[matt wilson]

Cutter .either the sigma or canon wide angles .I could not affordsthe canon and no doubt about it it's highly rated but so is the sigma at half the price .The sigma on my 50 d is one of my favourites you won't believe the coverage an ultra wide gives until you try it.

First thing I would check out on the 17 55 is the focus microadjust .Checkout the manual and you will see it is possible to fine tune focus on individual lenses .My 100 400 I found to be out (a lense can front or back focus in relation to the sensor )

Once corrected it is pin sharp and snaps into focus a lot quicker .

Try a google of af microadjust .

The method I went for was one where you mount the camera on tripod and shoot a test pattern on pc monitor.It really works.

[Cutter]

Originally Posted by chris-p

Hi Mark

Hmm, wideangle Canon fit lenses. I suppose you've really got 2 options, the Sigma 10-20mm is really popular and most people love it (I certainly do) or the Canon 10-22mm. Neither of which are anything near £1000 - but there isn't much in that range. Probably the sharpest wide angle would be the Canon EF 14mm f/2.8 but it's more like £2000!

I'm surprised that you can't get sharp images with the 17-85 though, how are you focusing? People tend to be a bit more sloppy with their focusing on landscape shots but, if you're after sharpness and lots of depth of field, the focusing is critical.

Also, since Flake has left it's not been mentioned that much but diffraction could be a real issue here. IIRC you've got a 50D which has a lot of pixels crammed onto it's sensor so the bottom diffraction limit is going to be pretty early on in the aperture range. What sort of aperture values have you been using, and what sort of focus settings have you used (ie, which points, AF mode or manual etc)?

Thanks chris , thought I would post the phoro so you can look at Data. thanks again for taking the time to sort me out


Is this as good as I could expect with my settings?

[chris-p]

Hmm, looks fine to me... dunno what anyone else thinks??????

It's pretty sharp from front to back. If anything, it looks sharper at 100% than at 50% (which is what my screen fits it to). It certainly doesn't seem any worse than the Sigma 10-20mm on my D90. In fact the only thing I can see thats technically wrong is the CA against the sky!

Did you shoot in RAW or JPEG (EXIF doesn't tell you that - or if it does, I don't know where)?

[matt wilson]

Not sure re sharpness .It looks a bit flat .i.e lacking in contrast and I agree about the chromatic aberation on the leaves .

Interesting review re the canon on ephotozine lens reviews .

a summary

The Canon EF-S 10-22mm f/3.5-4.5 USM delivered a very sound performance with a combination of very decent build quality and very good if not impressive optical results. If anything vignetting at wide-open aperture could be better. The center performance is excellent throughout the range with generally good borders. The level of distortions is surprisingly low and CAs are quite well controlled.
Naturally it makes sense to compare the lens to a serious competitor like the Tokina AF 12-24mm f/4 AT-X Pro DX. All in all the resolution figures are very similar. The Canon has less CAs and a better contra light performance whereas the Tokina shows less vignetting. The build quality of the Tokina is also a little better (the Canon is more than "good enough" though) and finally the Tokina is substantially cheaper (420 EUR vs 670 EUR locally).

So which one to choose ? Well ... that's still up to you. :-)

[chris-p]

Originally Posted by matt wilson

It looks a bit flat .i.e lacking in contrast

Yeah but I think it's a quick test shot so that's fair enough...

[cosmicma]

i don't know if this counts on such a small zoom range ( 10-20mm ) but zoom lenses tend to compress the background i would have thought you would be better off with a wide angled prime for landscape
it's not something i photograph very often ( i have no eye for it ) so i have no experience in this field

just a thought...

[ap4a]

Originally Posted by cosmicma

i don't know if this counts on such a small zoom range ( 10-20mm ) but zoom lenses tend to compress the background i would have thought you would be better off with a wide angled prime for landscape
it's not something i photograph very often ( i have no eye for it ) so i have no experience in this field

Compression is a the effect that telephoto lenses have on perspective. Wide angles open up the perspective and make far away objects appear much smaller than closer ones. Being a zoom lens has no other effect than what would be expected from any lens at the focal length selected.

In other words, if you use a zoom lens at 20mm the perspective would be the same as a 20mm prime.