There are several types of mini HD cameras on the market today, they are all relatively similar. Whichever one you choose, I suggest that you install a coated polarizing or UV filter over the lens. It will reduce sun glare and as a bonus it will protect the lens from scratches and crashes. Brands: B&W, Heliopan are very good.
Another tip about these CMOS cameras: they all could suffer from “jello” effect, it’s when the video wobbles around or when propellers look distorted. This is an issue with rolling shutter, because CMOS cameras capture by scanning the image in lines. CCD flight cameras are immune to jello because they capture the whole scene instantly. Quadcopters will jello badly because they vibrate more than airplanes.
To get rid of jello: mount the camera on shock isolating pads such as Moongel, or surround with lots of foam and remove all vibration from motors or props by balancing. If that doesn’t get rid of jello, next reduce the shutter speed if you have manual settings or install a ND filter to trick the camera into a slower shutter. Next is to try and increase frame rate in the camera settings, 60p or 120p will appear smoother than 24p or 30p. (p = progressive frames per second). If all that fails, then mount a brushless gimbal.
Common HD cams used in FPV
…And with any of these cameras you are going to need some CLASS 10 or greater SD memory cards, class # refers to how fast the card can write; 10MB/s (megabytes a second). A Class 6 might work for just taking snapshots, but for video class 6 is too slow and may freeze your camera.
I have had some issues with some brands of SD cards in my GoPro 3 Silver, after a lot of frustration and trial and error I know that only this PNY 32 GB P-SDU32G10-AZ works well.
For other brands of cameras, these Sandisks will be okay as well as the PNY above: