Tagged with pixels - Personal View Talks http://www.personal-view.com/talks/discussions/tagged/pixels/feed.rss Sun, 28 Apr 24 11:32:09 +0000 Tagged with pixels - Personal View Talks en-CA Sensor resolution vs nyquist sampling theorem http://www.personal-view.com/talks/discussion/22501/sensor-resolution-vs-nyquist-sampling-theorem Thu, 29 Aug 2019 13:29:07 +0000 EspenB 22501@/talks/discussions So, if I want to sample audio everybody knows that f = 0,5 fs. So to sample 20 kHz I need >40 kHz sampling frequency.

So if I have a camera system of i.e. HD resolution of 1920 x 1080 pixels the actuall resolution of this sample raster is only 960 X 540 pixels.

Yes or no? Actually somewhere in between?

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gh5 raw issue http://www.personal-view.com/talks/discussion/17356/gh5-raw-issue Mon, 17 Jul 2017 07:12:46 +0000 sebolla 17356@/talks/discussions hi,i was trying some timelapse in raw with long exposure and i had a lot of red white green dots on the image so i tried to test the camera in my room to see if the proble persist....well the shoot has been taken at f4 iso 320 6" sec exposure everything manual noise reduction turned off raw plus jpeg... the jpeg came out just fine with a few red dots almost invisible.... The raw file which i converted with lightroom and silkypix(the official panasonic raw developer) have hundreds of red green white dots mostly in the shadows area...to make it a bit clear i brought up the exposure by one stop... here are the 2 images... i don't know if i have a faulty camera,if someone could replicate a long exposure shot it would be really appreciated....thanxx

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Which CCTV lens for wide angle fisheye use ? http://www.personal-view.com/talks/discussion/7609/which-cctv-lens-for-wide-angle-fisheye-use- Fri, 26 Jul 2013 05:31:26 +0000 TruHype 7609@/talks/discussions Hello everyone,

I've recently started to get interested in C mount (CCTV) lens, for they are fast, wide, and cheap. So I wondered, is there any CCTV lens that I could use as a Fisheye (and get the same effect as the Panasonic 8mm f3.5, but faster) ? Here's a few lens I've found looking on the internet :

  • Rainbow 3.5mm 1.6

  • Tamron 4-12mm 1.2

  • Pentax 6mm 1.2 (+ wide conversion lens x0.45)

Wanted effect :

The GH2 exact m4/3 sensor crop is x1.86.

So I would like to get the same widness as the Panasonic 8mm or any 8mm Fisheye (Samyang, Peleng, Rokinon...) :

Panasonic 8mm : 8 x 1.86 = 14.88mm equivalent (no need for ETC mode)

Rainbow 3.5mm : 3.5 x 1.86 = 6.51 -> 6.51 x 2 = 13mm equivalent

Pentax 6mm : 6 x 1.86 = 11.16 -> 11.6 x 2 = 23.2mm equivalent -> 23.2 x 0.45 = 10.44mm equivalent

x 1.86 : GH2 Sensor Crop

x 2 : ETC tele conversion mode crop (to cover vignetting)

x 0.45 : Wide convversion lens

Does that mean we could use any CCTV c mount lens instead of the Panasonic lens to get the wide fisheye effect ?

A few videos :

Lenses :

C mount lens (1/2") work well on the GH2, but I heard that the CS mount lens (1/3") would still have really heavy vignetting because even with the ETC mode it would not cover entirely the GH2 sensor. Is that true ?

Interesting CS mount lens, but 1/3 inch : http://www.ebay.fr/itm/TAMRON-Manual-Iris-CCTV-Lens-3-0-8mm-1-1-0-ASPHERICAL-C-Mount-3-Mega-Pixel-/261248954560?pt=UK_CCTV&hash=item3cd3a6b0c0

I would use the fisheye to film Skateboarding.

Thank you.

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Smoothest hack, intra, macroblocking... Noob questions ! http://www.personal-view.com/talks/discussion/7420/smoothest-hack-intra-macroblocking...-noob-questions- Wed, 03 Jul 2013 18:17:07 +0000 TruHype 7420@/talks/discussions Hello,

Attention, noob questions ahead !

I would like to know a few things : - Which is the smoothest hack on the GH2 ? (All the detail, no macro-blocking) - What does "Intra" or "AVC-Intraa" mean ? - What is Auto Quantitizer ? I'm not sure if a higher number means a better image (lower compression) or it's the inverse. What is better, AQ0 (all to motion), or AQ4 (all to details) ? - What does GOP stand for, and there is "Low-GOP", but then does that mean there's "high GOP" ? What are 12/15 GOP, 3 GOP and 6 GOP ? - What are P-frames, B-frames... ? - What is "Matrix" and "444 Matrix" ? - On some settings there's written "14-16 QP", or "QP16". What does QP mean ?

I've not seen much smooth looking GH2 videos on Youtube (unlike the canon videos), lots of them have a lot of macroblocking or whatever and causes the video not to be smooth, and sometimes there are some sort artifacts (I think it's because of the compression or something...). I'm a bit of a pixel-peeper :P Could someone explain me the causes of the un-smoothness, and why are some videos really clean compared to others ?

Example of smooth videos I've found :

(his videos are all smooth and clean)

PS : Can someone give me the link to download the 244mb/s hack ?

And here on EOSHD there's an article about Intra :

http://www.eoshd.com/content/4452/gh2-gets-avchd-intra-at-176mbit

But I still don't understand the difference between the 176mbit so-called "Intra" hack and any other one ! I'm confused...

Please answer !

Thank You.

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Stuck green pixels on my GH2 LCD screen. http://www.personal-view.com/talks/discussion/3820/stuck-green-pixels-on-my-gh2-lcd-screen.- Sun, 08 Jul 2012 02:56:40 +0000 Loganm187 3820@/talks/discussions I just purchased my GH2 new from B&H last week and it already has three visible "stuck" pixels on the LCD. Is this a common problem with this camera? I can barely notice them when just looking at the LCD, but I just got my LCDEF and when using that they are extremely obvious and it drives me nuts! This really sucks as I have too many jobs coming up this month to deal with a return. I tried everything I could find online to remove them to no avail. Any help or tips guys?

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