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-   JVC GY-HM 800 / 700 / 600 Series Camera Systems (https://www.dvinfo.net/forum/jvc-gy-hm-800-700-600-series-camera-systems/)
-   -   My HM600 arrived =) (https://www.dvinfo.net/forum/jvc-gy-hm-800-700-600-series-camera-systems/513650-my-hm600-arrived.html)

Chris Harding January 21st, 2013 06:07 AM

Re: My HM600 arrived =)
 
Hi Jody

It's not all about sensor size and ISO/sensitivity...I upgraded from Panny HMC82's to AC-130's (1/4" up to 1/3") and the results were really poor and not anything like I expected...All that happened was the chips needed huge ND's in sunshine but still were noisy and poor at night and hardly an improvement at all.

I moved away from the 1/3" chip simply because of unusable footage at 18db+ and went for the Sony EA-50 with the APS-C sensor ....I have wedding footage now at 27db and it's clean and NO special noise processing either ....In that light with a 3 chipper that's about the best you can expect ...That's why I didn't even consider the JVC as much as the specs impressed me!!

If you want to avoid the poor low light of smaller chips then you need to actually downsize (as Noa says) to the little Sony...it uses backlit chips which see in the dark a lot better than conventional 1/3" chips despite them being smaller...otherwise you really need to look at cams with 2/3" sensors if you can afford them. I guess since this is a new camera and you certainly want to keep it, it's time to invest in a decent on-camera light!!

Chris

Noa Put January 21st, 2013 06:20 AM

Re: My HM600 arrived =)
 
Quote:

I have wedding footage now at 27db and it's clean and NO special noise processing either ....
Clean footage at 27db gain? 27db gain should be the equivalent of at least 5000 iso and I get a lot of grain in my footage at anything above 3200 iso.

Mike Beckett January 21st, 2013 06:44 AM

Re: My HM600 arrived =)
 
I guess it depends on what you view as "low light". I don't think it's a see-in-the-dark camera, that might be a bit too much to expect.

Shaun Roemich January 21st, 2013 07:49 AM

Re: My HM600 arrived =)
 
Mike: that's not the focus issue I describe but likely related. I suspect the lens uses a flange back look up table that adjusts on the fly as the lens focal length is changed and it was slow to respond at NAB. Wondering if that has been resolved.

Tim Polster January 21st, 2013 09:15 AM

Re: My HM600 arrived =)
 
Jody,

Thanks for your efforts here. I would be interested in the amount of noise at 0 to 6db under "normal" low'ish lighting where a pro might need to produce a great image. More to the effect of how low you can go without needing to use any gain.

27db is going to have noise on every camera no matter its sensitivity because the setting is 27 increments higher than its rating.

Shaun Roemich January 21st, 2013 11:55 AM

Re: My HM600 arrived =)
 
Further to what Tim states, remember that dB measurement is a Log20 scale; that is, an increase of 20 dB is a magnitude of order (ie. 10 times) the amount of image gain (I'd say "brightness" but that would be incorrect...)

So 20dB of gain would be ROUGHLY equivalent to about 3 and a bit stops of increase in sensitivity... which is QUITE a lot...

27dB of gain is somewhere in the neighbourhood of 4.5 stops or approximately 20 - 22 TIMES the amount of apparent brightness.

Sort of like the difference in the amount of light let in by a lens at f2.4 versus f11... That is a MASSIVE amount of difference...

Put it all in perspective now?

Noa Put January 21st, 2013 12:11 PM

Re: My HM600 arrived =)
 
Quote:

Sort of like the difference in the amount of light let in by a lens at f2.4 versus f11... That is a MASSIVE amount of difference...

Put it all in perspective now?
Yes, but even then there are camera's that can handle those high gains, like a fs100, without much issue, you might think this is because of the large sensor but my small sony handicam has a very small sensor and can push 24db of gain with less grain in the image then my xh-a1 displays at 6db. If jvc advertises a low lux feature that, from what I see in above video, is pretty useless I wonder why they even bother to add this to the camera?

Shaun Roemich January 21st, 2013 12:20 PM

Re: My HM600 arrived =)
 
Simple. News gathering. When you MUST get an image, regardless of quality.

Like Sony's HyperGain.

Noa Put January 21st, 2013 12:22 PM

Re: My HM600 arrived =)
 
which sony camera's have hypergain?

Shaun Roemich January 21st, 2013 12:23 PM

Re: My HM600 arrived =)
 
Most of the shoulder cams aimed at ENG. And don't kid yourself, the JVC IS intended as a New Age ENG camera, whether we shooters like it or not. It ISN'T a digital cinema camera.

Shaun Roemich January 21st, 2013 12:24 PM

Re: My HM600 arrived =)
 
Also: Z1, NX5, V1, EX1... the list goes on...

Noa Put January 21st, 2013 12:25 PM

Re: My HM600 arrived =)
 
Not sure if any expected this to be a cinemacamera but most recent small sensor camera's can display clean images at higher gains. That doesn't neccesarily mean clean at 30db gain but I would expect from a recent camera that 12 to 18db would be possible to handle right, considering that a small handicam can do it at 24db gain.

Shaun Roemich January 21st, 2013 12:36 PM

Re: My HM600 arrived =)
 
Sorry Noa... the "don't kid yourself" wasn't intended as hostile, especially toward you... just an observation in general.

Unregistered Guest January 21st, 2013 01:04 PM

Re: My HM600 arrived =)
 
Thanks for the demos. I was really psyched about the JVC HM-600 and was on the verge of buying it until I saw your demos. I was told that JVC has a reputation of exaggerating specs to make things seem much better than they actually are, apparently this camera is an example of that. I guess if it seems too good to be true, it probably is.

I'll just wait for NAB and see if Sony has a replacement for the NX5u, or maybe Canon will release something fantastic.

Jody Arnott January 21st, 2013 03:20 PM

Re: My HM600 arrived =)
 
Hey guys,

I'll do some further tests tonight. The tests I posted last night were in very low light that most people probably wouldn't bother shooting in without lighting. So I'll find a low light scenario that might be more typical, and post the results later.

Until then, it's lunch time here so I'm going to head out and get some test footage.


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