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

Started Dec 3, 2012 | Discussions thread
ProtoPhoto Contributing Member • Posts: 984
Re: I think I got it right this time

Jamon47 wrote:

Buuuut... in VLL the 60p picture shows a shutter speed of 1/30 coming from a camera automatically set in Auto Mode and from a sensor output of 60fps, that was a surprise to me... how can a single 60p frame that has been in the making in the sensor over a period of 1/60 of a second, be exposed over a period of 1/30 of a second. The frame was delivered by the sensor half way trough the exposure period, the rest of the light gathered went to the following frame... I thought.

So I went back and read your post again and I thing I got it right this time.

In your example, with a 1/15 shutter speed the sensor waits the full 1/15 sec duration to take a reading and then the image processor generates 4 identical consecutive frames with this reading when shooting in 60p or generates 2 identical consecutive frames with this reading when shooting in 30p. So each of these 6 frames would show exactly the same IQ (corresponding to a 1/15 exposure).

Applying that to the HX9V shooting in VLL, when set to 60p the shutter waits the full 1/30 sec duration, takes a reading and then the image processor generates 2 identical frames. When set to 60i (which for the HX9V is similar to 30p) the image processor generates only 1 frame but it would be identical to the previous 2 frames.

From my earlier VLL static scene video test I would now guess that the slowest shutter speed the HX9/20/30V automatically set is 1/30 and not /160 as I suspected before.


To the original question: with the HX9/20/30V does 60i (or 30p) deliver visibly better IQ over 60p in LL and VLL conditions?

My answer still is: there are no visible advantages, from an IQ perspective, in selecting 60i (or 30p) over 60p when shooting videos in Low Light and Very Low Light conditions.

Hope this helps.

It certainly did and thanks for your patience

Yes, you got it, that was exactly what I was saying, and I am glad I could help!

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