photonius

as you can see, the 18-55  lens is so good that at f11 resolution is getting worse because of diffraction (of course you might want the increased dof for landscape)

Indeed, none of the shots are as sharp as they could be. In the first shot, even though focus is on close subjects, there is nothing closer to the camera on which the AF could have locked. In the...

yes, that's what I also thought, but it still doesn't look completely sharp, but it's difficult to tell since it's mostly black.

No, no newer tests, just some additions http://www.lenstip.com/119.1-article-Polarizing_filters_test_-_supplement.html http://photonius.wikispaces.com/Filters With B+W filters, you have to look at...

The last point is certainly true, not recommended. In particular this will also give vignetting at 15mm (point 2), the combination will be too thick, the 15-85 suffers already from vignetting itself.

Yes, looks like something is going on, but seems difficult to get detailed information. Still work in process I guess. What we would be wishing for of course is that Canon implements something like...

As mentioned, this may not always give the best result, since the camera tends to take the closest points. It sure looks like the focus was in front of the right man, but even then it looks too...

yes, aperture, shutter speed, focus mode, etc. would be useful to know. Did you shoot in full auto (green auto)? usually that uses all AF points, and the camera tends to select the closest one,...

compromise: 17-55 f2.8 IS. otherwise I would say you need both, 15-85 for range, and 18-35 for low light.

The XSi takes EF and EF-S lenses, and third party EF mount lenses. Yes, the 55-250 is a good match for the kit lens (18-55 IS), but of course you can also choose say a Canon 70-300 IS lens (which...

well, the sensor in the 60D and Sl1 is very similar, The SL1 is newer, with on sensor phase-detect pixels, so you can do continuous focusing during video (mainly with STM lenses).  Otherwise, the...

sounds indeed as if the battery is not good anymore, and holds little charge. try a new one.

I looked at it, I do not see anything that is wrong. Where are the duplications supposed to be?

what lenses do you have? it sounds like you have large documents that may not require a macro. what you need is a good stand and remote control.

It does suggest then that there is nothing major wrong with the lens. So, as mentioned, the 24-105 is sort of borderline with vignetting, and if the optical axis is off from the center with respect...

As mentioned by meland, aperture blades cannot do this,  you do not see them, the control how much light comes in. stuck blades would cause wrong exposure. The only time you see the aperture blades...

Some question, was there a hood on the lens? Maybe the hood is bent/misaligned? If no hood, you have encountered yet another issue that lenses can have (apart from the usual front/back focusing,...

Well, I was not specifically suggesting the 7D II, but the sensor should then trickle down to the Rebels etc., like it did from the 7D to the 550D(T2i).  I totally understand, that's why the 550D...

That's the whole point about RAW, it's the raw image from the sensor that is stored, nothing really to adjust. The only thing that can affect it is Highlight tone priority. You process the RAW...

well, since you plan to stay on crop for weight reasons (nothing wrong at all with that), and no other crop (or smaller) camera gives much less noise that satisfies you, you have to indeed...