Noise problem with AG-HPX370

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bluevoyagetv

Member
High folks. I recently upgraded my gear from hmc150 to hpx370. I used hvx200 and hpx170 for many projects. This hpx370 has weird video noise. Especially shadows are very pixelated. I am using AVC-intra and cutting it on FCP... I changed scene files to BBC video and BBC film ... it did improve but I can still see the pixelation. My HMC150 had less noise... what might be the problem?
 
I did some test shots in 720 60p 1080 30p 1080 24pn etc.... my vfr was either off or I used 60... to see the slo-mo... almost all had some noise... I am editing it now to post on youtube... I will post the link.
 
Are you seeing the pixelation in you edit system as it may be that the codec is too much for your set-up if you are using AVC Intra?

What is the spec of your edit set-up?

Once the master file is rendered you may not see the problem!
 
This is probably a silly question but have you accidently knocked the gain from -3 to +something? I did it once myself. Also check the master pedestal isnt set to high, i usually run mine at -6 to -9. One last thing, the 370 ships with its pap noise filter set to type 1, this can sometimes shows noise like shimmering in some backgrounds. change it to type 2 and it should mostly go away.

I went from an hmc151 to the 371 and it was way cleaner than the 151.
 
It'd help to know all the settings used. Assuming a well-lit subject and shooting at -3db, there isn't much noise visible on my 2560x1440 monitor, so on a typical HDTV the image should be pristine.
Unlike most of the cameras you mentioned, the HPX370 records all 1920x1080 pixels of resolution and AVC-I saves the data at 100mpbs, so the noise could simply be data that otherwise usually gets smoothed over by compression and/or low resolution.

Also check the master pedestal isnt set to high, i usually run mine at -6 to -9.
Click to expand...
I dunno if it is that... I once did a test where I shot a clip with master ped at +60 and the footage looked just fine even after I messed around with the shadows in post.

The two biggest detriments to image quality on the 370 seem to be back-lit subjects or if you have generally under-exposed the footage. You should not, for any reason, let the exposure of your mid-tones dive below 25ire or so on the waveform, or it's noise city.
 
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Hi Kolor, i dont tend to do much in edit so i like to crush the blacks a little in camera. Of course if you set a ped to + then you reveal the shadows and get a flatter image which is ripe for manipulation later :)
 
Garion said:
This is probably a silly question but have you accidently knocked the gain from -3 to +something? I did it once myself. Also check the master pedestal isnt set to high, i usually run mine at -6 to -9. One last thing, the 370 ships with its pap noise filter set to type 1, this can sometimes shows noise like shimmering in some backgrounds. change it to type 2 and it should mostly go away.

I went from an hmc151 to the 371 and it was way cleaner than the 151.
Click to expand...

Thanks for the info I changed the P.A.P filter to 2. and checked rest of my scene files... I will try it again
 
Garion said:
This is probably a silly question but have you accidently knocked the gain from -3 to +something? I did it once myself. Also check the master pedestal isnt set to high, i usually run mine at -6 to -9. One last thing, the 370 ships with its pap noise filter set to type 1, this can sometimes shows noise like shimmering in some backgrounds. change it to type 2 and it should mostly go away.

I went from an hmc151 to the 371 and it was way cleaner than the 151.
Click to expand...

Thanks for the info I changed the P.A.P filter to 2. and checked rest of my scene files... I will try it again
 
I forgot to say i always Black balance when i first turn on camera and when i change scene files, that helps a little too.

Sometimes when im playing with scene files and want to check noise levels, i leave the lens cap on and activate the waveform monitor. Then i can see the noise floor level and mask it with the master pedestal, its quite surprising how the noise changes with differant gamma setting etc.

Note: I usually only do this when i know i'll be filming in dark interiors and will have to use a little gain as the camera is quite clean normally.
 
Ok so just to make sure, I just shot a test clip (doing the usual as Garion described, noise check with cap on, wave form, etc) using Cine D Gamma, -3db. I can maybe see some "peach fuzz" at 100% view in dark/flat parts of the image, but nothing offending...
 
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