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Canon 24-70 L
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Hi all
I got my 24-70L lens at B&H in New York in February.
I was wondering can anyone advise me of tests that I can do to test its sharpness and other criteria as I am reading more and more about some people getting bad lenses of this type.
The quality seems OK to me but I would like to know for sure as its not exactly a cheap lens.Any help would be greatly appreciated.
If anyone has the same lens an upload sample pic would be great or if anyone needs me to post anything, let me know, ill be here all day.
please help
regards
JohnI saw this, someone else on PI posted it, so I’m not sure how good it is. I haven’t tried it yet.
http://www.focustestchart.com/focus21.pdfCanon usually are very consistent, from what I read, it is the third party brands that seem to have the variability in lens quality in some models, although I have a cracking tamron.
Martin
download a focus chart and use it per instructions. while canon lens are not in he same league as crappy sigmas some do have focus issues, notably the 24-70 and even slightly out of focus at a wide aperture can lead to soft piccys.when using the focus chart make sure the lens is focussing exactly on the line and the pics reflect that as the 24 should be acceptably sharp even at 2.8
Hi all
Here is a shot I took with the 24-70 tonight.
This to me seems sharp but on the majority of my other pics this is not the case ….maybe I need to apply the KISS theory..keep it simple shutterbug.
What do you think folks???
This is a compressed image, so sharpness can be ruined by the resizing. Can you post a crop from the sharp area instead? In many cases when someone is complaining about the sharpness of a lens, the autofocus or the user needs adjustments… What camera body do you use it on? Can you repeat the test, this time focusing on something particular, that is small enough (like the middle of the crest on this box). Also, you are quite close, even the smallest movement can affect the sharpness, are you using a tripod?
Search the dpreview.com forums, people over there are always concerned about sharpness and they always think they got a wrong copy of a lens….
Zoltan
Lot’s of things can affect sharpness. In fact, this was something that really troubled me for some time when I moved from film to digital. I found digital to be really unforgiving in this area and have tightened up my shooting technique a lot as a result.
Some of the things that will affect sharpness include the following:
1. Aperture – many lenses can be quite “soft” when used at or near their maximum apertures and gradually improve as you stop down until you reach a point where things go backwards again due to diffraction caused by smaller apertures.
2. Camera shake – this is by far the most common reason for unsharp images.
3. Area of focus sensor – this is usually larger than the focus indicator in the viewfinder and the camera may not be focusing on what you think it’s focussing on.
4. Focal length – if it’s a zoom lens, sharpness can vary throughout the focal length range of the lens.
5. Subject movement – shouldn’t be an issue if your shooting still subjects, but it’s often a cause of unsharp images when shooting portraits for example.
I’ve probably missed a few, but these are the mains ones I can think of right now. If you’re 100% sure that none of these are contributing to your problem, then it’s possible that there may be a focus calibration issue.
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