Upgrading from Rebel XTi

[mattbaume]

I just upgraded from the XTi to the 6D and I'm very happy with it -- much more responsive autofocus, looks great in low-light, and it's very nice to have a full-frame sensor. The WiFi functionality is nice in theory -- it allows you to wirelessly operate the camera and transfer photos with your phone or computer -- but the menus to make it work are so confusing and poorly implemented that I'll probably rarely use that particular feature.

One small thing to watch our for is lens compatibility. The XTi can use EF and EF-S lenses, but 6D and similar models can only use EF. (An EF mount will have a red dot on the ring; an EF-S mount will have a white square next to the red dot.) Both of your 1.8 lenses should be EF, but I believe the XTi's kit lens (which you say you don't use anyway) is EF-S, so if you ever wanted to use it you won't be able to.

 

[TCampbell]

One small thing to watch our for is lens compatibility. The XTi can use EF and EF-S lenses, but 6D and similar models can only use EF.

That's not a drawback, btw. The "S" in EF-S stands for "Short back focus". With the popularity of APS-C crop-frame camera bodies, Canon realized that they didn't need the full image circle large enough to fill a 24mm X 36mm sensor. The EF-S lenses only project an image circle into the sensor body large enough to cover the APS-C sensor AND since image quality degrades as the distance from the central axis of the lens increases, it's cheaper to build lenses that don't have to provide full coverage. Basically you can build a lens for less money which still produces high quality if it's designed just for the sensor size you need. That's what an EF-S lens is.

The reason you can't use an EF-S lens on a full-frame sensor body is twofold: (1) the lens isn't designed to provide an image circle large enough to fill the sensor with adequate quality and (2) the rear-most element on the lens is set back into the camera body a bit (it actually extends into the body beyond the lens flange). A full-frame camera requires a full-frame mirror and full-frame finder. A crop-frame body only requires a crop-frame mirror because it has a crop-frame finder (not the sensor... the finder.) That means the mirror on a full-frame camera is physically larger. Since a crop-frame lens' rear-most element sits back farther into the camera body, the mirror does not have enough room to swing clear of the lens element. Canon deliberately designed a ledge inside the camera body (because the mount & flange design on EF vs EF-S actually are identical) and the ledge prevents the EF-S lens from being attached to a full-frame body to avoid the unpleasant consequences of a jammed or damaged mirror.

 

[LaurieBeth]

Thanks for the info on the lenses. I'm really not interested in using my kit lens for much. I'm hoping to invest in a good zoom in the not-so-distant future.

 

[texkam]

Consider the T4i as well. They've been as low as $599.00. Money left over for the 17-40 f4L.

 

[FilmaTroy]

Since you are just looking to improve in a body that will be better than the xti, go ahead and get the 60d which is the least costly... then sell that stock lens for whatever you can get it for, and invest in some kind of L lens. 24-70 2.8L or if you need something a little cheaper with awesome quality the older 28-70 2.8L is awesome as well and only about 950 or so used. (I have one for the past year and love it!) it will also help in low light having the option to drop to a 2.8 aperture