HX9V/20V/30V: Does 60i (or 30p) deliver better IQ over 60p in Low Light?

You don't need a test to confirm these questions...less light means a darker image regardless of it being a photo or still from a video or a video.  You don't normally shoot 360 degrees (1:1), you normally would shoot 180 degrees and hence the thinking that you get more light shooting 24p (or 30p) than you do at 60p.  At 24 or 30p, each frame should get light from a shutter at doubled the inverse speed.  So for 1080 60p you would shoot at 1/125, and at 24p you would shoot at 1/50 or 1/60.  In order to compensate you increase gain (iso) and here is where the trade off is.  Also, 60 frames per second is a lot of information to send through limited bandwidth so you need lots of light to lower the gain and get clean images. When I run out of light I always shoot 24fps because it gets me more light since I am now shooting at 1/50 or 1/60 shutter speed, and that is obviously more light than I would be using at 1/125 shutter speed for shooting 60p.  So yes, if you are following the 180 degree rule shooting 30p will get you more light in your shot...and then you can do things like lower ISO to get better quality from that video.  With a constant F stop, and constant gain (iso) setting, you will obviously get a better video shooting 30p @ 1/60 shutter speed than you would shooting 60p @ 1/125 shutter speed.  And again all these rules are just rules, you can shoot slower or faster shutter speed independent of your frames per second for various creative reasons (motion blur, or extra jittery crispness if you desire it)

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