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-   Sony NXCAM NEX-FS100 CineAlta (https://www.dvinfo.net/forum/sony-nxcam-nex-fs100-cinealta/)
-   -   25P juddering motion. (https://www.dvinfo.net/forum/sony-nxcam-nex-fs100-cinealta/497386-25p-juddering-motion.html)

Brian Bang Jensen July 4th, 2011 12:28 PM

Re: 25P juddering motion.
 
Quote:

Originally Posted by Felix Steinhardt (Post 1664284)
Nope, the GH2 resolves over 820 Lines. That´s a lot more than the FS100.

But as you and Alister said, it must be solved with the detail adjustments.
I´m getting the camera next week and first thing I do will be messing around with the detail options.

If you got a camera with a far superior picture, why buy the FS100??

Brian Drysdale July 4th, 2011 12:44 PM

Re: 25P juddering motion.
 
Given that people seem to be talking about 780-800 lines for the FS 100, 820 lines doesn't seem to be a difference to be getting excited about. There are other factors like dynamic range, skin tones etc to be included in the comparison between the cameras.

Since it's still early days, I imagine people will be running tests over the coming weeks for the best camera set ups.

Felix Steinhardt July 4th, 2011 01:16 PM

Re: 25P juddering motion.
 
Quote:

Originally Posted by Brian Bang Jensen (Post 1664294)
If you got a camera with a far superior picture, why buy the FS100??

More lines = better picture ?... D´Oh! ;)

By the way: I just bought the german video magazine "Videoaktiv Digital" and they meassure the vertical resolution at 671 line pairs (horizontal 660 lp)

Steve Mullen July 4th, 2011 10:47 PM

Re: 25P juddering motion.
 
2 Attachment(s)
These Figures are from my new eBook sold by Broadcast Engineering.

You'll see that with a camera that only has a Sharpness control, you can only hope to reduce the boost without reducing resolution too much. (The dotted line.) Don't fully reduce Sharpness as it cuts resolution too much. (Red line.)

The other graph shows the anti-jutter curve available with Cine Alta cameras. It acts to suppress edge sharpness without reducing fine detail.

Steve Mullen July 5th, 2011 12:05 AM

Re: 25P juddering motion.
 
Quote:

Originally Posted by Brian Drysdale (Post 1664298)
Given that people seem to be talking about 780-800 lines for the FS 100.

I have a many many year old spreadsheet that estimates measured resolution based upon camera technology and sensor size. My estimates for the FS100 is 737 and 732 lines for H and V.

Brian Drysdale July 5th, 2011 01:58 AM

Re: 25P juddering motion.
 
Resolution seems to be one of those tests were figures seem to go all over the place, becoming even more confusing when TV line results are mixed with tests using line pairs. Combined with the different methods being used and people's interpretation - the recent Single Sensor Evaluation seems to have raised some issues in this regard using film methods with digital sensors. Certainly some of the figures were higher than found by other people.

Alistair's figure with the supplied zoom lens was 770 line widths/per height: http://www.dvinfo.net/forum/sony-avc...p-bloom-5.html

The much quoted Nigel Cooper DVuser review with the same lens says 780 lines - I'd assume TV lines.

At first glance, the "Videoaktiv Digital" test would seem to give more resolution to the FS100 than found by Single Sensor Evaluation for the F3, which had 530 line pairs /image height in their test. All rather confusing.

Steve Mullen July 5th, 2011 01:14 PM

Re: 25P juddering motion.
 
When VC releases their 4K2K camcorder at IBC expect to see a resolution of 2062 LW/ph and LW.

If Sony releases a 4K2K version of the VG10, using their 16MP chip, my estimate is 2224 LW/ph and LW!

Remember Juan stated that SLR lenses offered twice the MTF as need for Full HD. So these new camcorders will be able to fully take advantage of high quality lenses.

One has to wonder how these low cost camcorders will handle 25p and 30p in terms of judder!

Alister Chapman July 6th, 2011 01:27 AM

Re: 25P juddering motion.
 
My resolution results are at MTF50 so finite resolution would be somewhat higher, typically 30% higher which would be around 1000 LW/PH .LW/PH is pretty much the same thing as TVL and both of these are 2x LP/PH. LW = Line width, ie the width of a single line and LP = Line Pair which means both a black and white line. After all you can see the white lines if there are no black lines in between.

It still confuses me and you must tread very carefully when measuring resolution. In the SCCE tests they used a slant edge measurement method (the same method I use in my MTF50 tests) but this does not take into account aliasing effects so the results are hard to interpret when you are trying to measure finite or limiting resolution which is often around Nyquist and the onset of aliasing (false detail). MTF50 tends (but not always) to be away from aliasing so generally is more consistent but it is not the finite resolution of the camera, which will typically be around 30% higher than MTF50. MTF50 also tells us how sharp the image will be perceived, while finite resolution is invisible under normal viewing conditions so can be misleading.


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