The Canon 5D Mark II, and now the Canon 7D, are digital SLRs that have HD video capabilities. Video on a camera is nothing new, and “prosumer” point-and-shoot cameras have been able to do HD for a while now. SLRs are different, for two reasons:

• Much like Live View (the ability to preview the image on the LCD), it shouldn’t be possible. An SLR has a mirror that sits in front of the sensor (formerly film, now CCD/CMOS), which redirects the image up into the viewfinder. When you squeeze the shutter, the mirror is lifted, and dropped as soon as the shutter closes. This is why you have to hold SLRs up to your eye while composing a shot. (And why you can’t see through the viewfinder while the shutter is open.)
• SLRs have nice lenses allowing things like low-light performance and shallow depths of field.

Between HD and the high-quality optics, you can end up with some amazing films that look straight out of Hollywood. (Except that it’s first-generation quality and often has onboard sound… But I digress.)

I passed over the Rebel T1i as an unneeded frivolity, even though it greatly expands my ISO range (improving low-light performance) and adds full HD video. I just stumbled across a neat post by Dan Chung, who got his hands on one of the first production Canon 7D cameras, and produced Another Night in Beijing, the first of the two videos on that page.

Now I’m really regretting not having purchased the T1i when it was $800 with a $300 printer included…