pokokarin wrote:
Can this lens be used with a crop sensor camera or is it specific for a full frame.
ANY Canon EF/full frame lens can be used and will work fine on ANY Canon crop OR full frame camera made the last 30 years.
All but the oldest (10D, D60 and D30... about 2004 and earlier) Canon APS-C crop cameras also can fully use ALL EF-S lenses.
It's only the full frame Canon cameras (and several older APS-H/1D-series models) that are limited.... they can only use EF lenses.
There are two versions of the EF 24-105mm f/4L IS USM lens. The original 2005 version is still widely avail. new ($1000). Sorry, but that one never impressed me very much. The far less expensive EF 28-135mm IS USM (about $400 with hood) gives just as good image quality, focus performance, image stabilization and close focusing ability. They seem to be about equally reliable, too, although the 28-135mm doesn't seem as well built (it's more "plasticky" feeling than the L-series lens). Over the years I've had four or five of the 28-135s (most bought used for under $200) and one of them had an aperture fail. But the original 24-105L tends to have problems with flex cable failures. And its red stripe sometimes falls off (of course, that's merely cosmetic and doesn't effect performance in any way).
I haven't used the newer EF 24-105mm "II" (2016, $1100), so can't say from personal experience. I know it has improved IS and uses the new "Nano USM" focus drive, but all the reviews I've seen haven't been particularly enthusiastic about it's image quality.
There also is a less expensive non-L EF 24-105mm f/3.5-5.6 IS STM lens (2014, and about $600). I've never use it, either. I think it's been sold in kit with the 6D.
Personally, I REALLY like the 28-135mm (1998, but still in production) as a lightweight, general purpose, walk-around lens on crop-sensor cameras where it acts as a "normal to moderate telephoto". For a lightweight hiking kit, I often carry it, an EF-S 10-22mm and a 300mm f/4 with a 1.4X. I also use a bigger, heavier 24-70mm f/2.8 at times and like it better on APS-C than on full frame... though I might feel differently if I were a wedding photographer. I imagine any of the 24-105s can be equally useful.
If you don't have a full frame camera or plans to get one in the immediate future, you also might want to consider the EF-S 15-85mm IS USM. It sells for about $825 (with separately sold lens hood), is more compact than any of the above, and it's image quality, IS and focus performance rival that of any L-series... Plus it offers a great range of focal lengths on a crop camera. Might not need an ultrawide zoom.