Noise from low gain on HD for SD output

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Panamaniac
I am not completely versed in the effect of turning up the Gain. My take on it is that it makes the image grainy.
I never use gain but I was wondering today if using limited amounts such as the lowest settings of 3dB or maybe even 6dB in an HVX would generate a low amount/small enough grain that it may not show in a 480i render of 1080 and possibly even 720 footage?
 
Highly subjective- test for yourself. In general I avoid gain like the plague because it adds noise. But maybe that's ok in your applications.

Noah
 
The general consensus in the tv world is that you can use up to 9dB of gain on most professional SD camcorders to get broadcastable quality. I think that also applies to the HVX in SD mode. In my personal opinion the HVX with 9dB gain looks a lot like a DVX without gain... ;)
 
Really? 9dB on the HVX but are you speaking of ENG? I do catch gainy stuff even on CNN from time to time. Did I mess up my tests or is there something you do in post that I don't know of like the noise reduction? Please elaborate.

I am still not sure for narrative though I performed little tests... so far I think3dB and possibly 6dB might be ok, depending on light, when going from 720/1080 to 480. There is no question after performing the tests that this is subjective and possibly more of a creative choice at times especially at 6dB because while it might not throw you off the story it is noticeable much like "Reign Over Me" shot on the Viper.

I am sure that 3dB will work for 720 to 320 for web, and I think well lit 6dB too.

LOW light 12dB from 720 to 480 reminded me of some available light scenes from a 16mm movie shot in 2000... no... MUCH worse... but I have to admit it does look cool for certain moods like it did for the film I am speaking of. However that's something for post of course.

I guess if you are stuck and that's all you can do then punch your producer in the nose and shoot with gain...? lol

I have not shot with any gain either but I will look into 3dB a little more just to know for desperate situations. Have anyone of you used it in a project at all?
 
Hey, there was some talk way back when about gain on the HVX helping to break up the larger "blocky" noise patterns. I haven't tested thoroughly, but if you are, Roberto... see what you can surmise about that!
 
Really? Blocky patterns? So you mean I should compare 3dB to 0dB of equal rez...? How could that be a good thing? I mean I guess I understand what you are talking about but I'd love to see a section of a screen shot with these blocky patterns you are speaking of.
 
I thought some of the added noise from the gain might be small enough to be spread amongst multiple pixels and become less noticeable. I'll check it out a bit more soon.
 
Don't do it. If you really need more light, on event coverage, for example, buy a small additional on board lamp. The maximum acceptable noise, at least for my applications, is 3db. n my TV commercial work I never use gain. I'd rather go 25p and 25 shutter- Ntsc should be 24p 24 shutter. Blurrier plans and movement, but a lot better picture.
 
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