I need to do streaming video for a client that is currently using, I believe, a Grass Valley ADVC110 A/D converter from a consumer grade video camera with composite output. I know the HDMI is not clean, but how about the analog? I could use the 5D III if it at least has clean output on the composite cable. Will it record HD while sending a clean composite SD signal? Thanks!

To leave any door open, I need a camera system that is VERY good in low light that can capture HD yet also do an occasional live web stream. The Canon C300 is not in the budget and I would like something that has both a good low-light sensor and nice selection of fast zoom lenses like the Canon f2.8 24-70mm. I'm not so sure the Sony Super35 sensor cameras are a good idea as their E-mount zoom lenses are f3.5-5.6 instead of a constant f2.8.

Don't know about the 5d but the 550d and 650d uses the USB port with an A/V adaptor on the end. There should be one with the 5d when you bought it.

I have yet to purchase a camera for this job and I need to know if the usb-analog composite output has a clean SD signal that is suitable for web streaming. If it also has a white box, like the hdmi signal, then this camera is not useful in one very important way.

How about the Nikon D600 with a 24-70mm f/2.8? It has a clean HDMI out.

As a side note, the line skipping from DSLRs make SD video almost unacceptable for professional work. If you're aiming for SD, record HD and transcode in real time with something like this.

Even better would be the new Panasonic GH3, but it isn't shipping yet.

Thanks, Donald and Sareesh. I think I'm not going to recommend a dslr for video since the audio workflow is more time consuming. The line skipping isn't as much of a problem for the 5Diii, and I thought its 35mbps vbr would be vastly superior to the 24mbps of the Sony FS-100 but that doesn't seem to be the case from videos I have watched. I found out about the metabones EF-NEX adapter that will allow a nice assortment of lenses to work with the Sony FS-100 so I think I am going to recommend that camera instead. I was concerned about the lack of professional quality NEX lenses but that doesn't seem to be an issue with all the adapters available. I still want a 5Diii for my own photography, but I think there are better solutions for a video workflow now.