24-105 Sharpness

I have came to the conclusion that my 24-105L lense is soft on my 7D verses when it is on my 20D. I also have a 85 1.5, and it is tack sharp on both bodies. It also doesn't matter if I use the AF or MF. Has anyone else experienced similar issues? I am assuming a MA may be needed to resolve the issue. Just not sure why it would be softer on the 7D, but sharp on the 20D.

Thanks in advance.

How about some pictures to show what you are seeing?

Try Focal software to micro adjust the lens. It did wonders for my 70-200mm on my 7D

How are you comparing?
18mp 100% crops is not the same as 8mp 100% crops.

How does the AA filter on the 20D compare to the 7D?

I've been lucky enough to never need any MA with my 24-105 on any of the bodies I've used it on and it's been sharp on all of them. I'd suggest trying to use the MA facility to get it how you want it as it really can give superb results.

It used to be one of my most used lenses until I got a Canon 70-200 f2.8L MkII and a Sigma 24-70 f2.8 HSM and now the 24-105 is almost redundant but I don't want to part with it just in case.

wouldn't surprise me some first generation L lenses don't have the resolving power for the new higher MP crop sensors.

which explains it looks better on the lower MP sensor to you.

The 7D is much more demanding on lens resolution than the 20D. All things considered, and if the lens is microadjusted correctly the 7D will appear softer for sure. But resized down to the 20D image size it should look quite a bit better.

Yeah, MA may be needed to get the best out of the lens.

Superintendent wrote in post #15402641
It also doesn't matter if I use the AF or MF.

If this is true, then MA won't necessarily make any difference.

Try your 24-105 on your 7D using liveview, with a tripod, zoomed in and AF on some smallish font at the distance you most use the lens at. Do this in good light with an aperture of about f/8 and using a low ISO. I tend to m.a. zooms at the long end first then retest at the wide end.If it isn't sharp, m.a. in increments of +/- 5 between -15 to +15 and see if one image stands out as sharper than the rest. If so, then repeat using m.a. increments of +/- 1 around the setting that gave the sharpest result. You should see a big improvement over your original soft images. If not, suspect a lens problem and you may need to let Canon have a look at it.

For what it's worth, I've had my 24-105 for 4 and a half years and used it on a 40D, then a 7D and now a 5DIII. I would say it was always OK, without being brilliant, on both the 40D and 7D, but the 5DIII has shown a marked improvement in the IQ from it. That's with everything else being equal - ie if I did a comparison of all my lenses on the 7D vs 5DIII, the 24-105 is probably the biggest improver on the 5DIII.

Col

Superintendent wrote in post #15402641
I have came to the conclusion that my 24-105L lense is soft on my 7D verses when it is on my 20D. I also have a 85 1.5, and it is tack sharp on both bodies. It also doesn't matter if I use the AF or MF. Has anyone else experienced similar issues? I am assuming a MA may be needed to resolve the issue. Just not sure why it would be softer on the 7D, but sharp on the 20D.

Thanks in advance.

20D vs 7D....

This is a very common mistake that people make, coming from a lower resolution camera to one of the more recent, very high resolution APS-C models. If you look at images from each of them in exactly the same way - such as at 100% on your computer monitor - you are actually viewing the 7D images almost 50% larger, so are looking at them far more critically. For a truly fair and accurate comparison, you need to reduce the 7D image files to the same dimensions as the 20D files.

But, it needs to be noted that the 7D uses a much stronger anti-alias filter (to reduce moire effects). Probably because 7D was the first of the 18MP models and might be more susceptible to moire issues. The AA filter is a lot stronger than the one on the 15MP 50D. It's certainly stronger than all other lower resolution crop cameras such as the 20D. The strong AA filter simply means you need to apply stronger sharpening to images from 7D.

It appears Canon has also dialed back the strength of the AA filters on the subsequent 18MP models (i.e., T2i/550D, 60D, T3i/600D and T4i/650D). Or, it's possible they have written the processing algorythms of the later 18MP models to apply more in-camera sharpening to the image files... Maybe Canon is assuming that 7D users were more likely to be experienced shooters who are in the habit of applying sharpening post-capture or adjusting settings to apply more sharpening in-camera, more likely to be seasoned users who know what to do with their images and prefer to do it themselves.

It wouldn't hurt, though, to try Micro Adjust with any lenses that seem soft.

Also be sure to remove any filters from lenses, before being too critical of sharpness. Some lenses handle filters better than others. Don't know about the 24-105, but it's pretty common knowledge that a filter on a 100-400 is a problem, for example.

Finally, there's always the possibility that a lens is out of calibration. It happens with wear and tear. The 24-70/2.8 "Mark I" is known to get out of calibration gradually, with use and over time. I don't know about the 24-105, but any zoom has a number of moving mechanisms.

The 24-105L is quite mediocre in the sharpness department - it's usable, but never reaches the crisp sharpness that other lenses reach

smorter wrote in post #15407763
The 24-105L is quite mediocre in the sharpness department - it's usable, but never reaches the crisp sharpness that other lenses reach

A few shots taken recently that gave me the impression there is an increased level of sharpness from my 24-105 after I moved it to the 5DIII. As mentioned above, this is after comparing it to the differences in my other lenses after the same move. Of course it may just be that my copy of the 24-105 and my copy of the 5DIII are a good match, QC limits-wise...