Frage von Torben:
Hello,
unfortunately I could find no information on the subject. I now know that the color red is difficult to handle in every way. The DV format has a red-weakness, as synonymous with the special red-sensitive CCD chips.
Now to the actual problem: I have some time before the Canon MVX3i bought because it has been shown in many reviews from a "good choice", sometimes even better than the cheap 3CCD models of Panasonic. Unfortunately, some reds cause 4 pixels high Störstreifen / blocks in the video recordings. Both a direct transfer to the television as synonymous via Firewire. The recordings for other colors always comes out very sharp, the aforementioned effect, however, avoided any recording where a little more red occurs (eg fire, red stage lights, red, mousepads, etc.). To see the effect here:
www.neotos.de / downloads / beispiel.tif
The photos of the camcorder are completely normal, however:
www.neotos.de/downloads/IMG_0175.JPG
And a video on motion for clarification:
www.neotos.de / downloads / drehlampentest.rar
The effect occurs is independent of E-Lock, exposure, white balance and Aperture.
My question is: Am I too sensitive or is my camera broken? How much should I pay for this effect have not, finally, this camera has already cost 1300 ¬?
None has been able to help me, no dealer, nor Canon Canon Support Service Workshop. All this problem is unknown, but I can not say whether this is normal or not.
Thank you very much
Torben
Antwort von GhostDog:
Well, Rotschwäche I would not call it.
All the situations that you show here, are indeed fully maintained in a unausgeleuchteten, underexposed area on a red light until it is completely white, without drawing overridden. The compositions are simple, which should be avoided for video ever.
I still dare to even a theory what's happening here:
1. The MVX3i indeed created (which is why its picture quality as good as synonymous) is a video of pixels 4 pixels of the CCD. In the photo mode, each pixel is individually Resolutiongenutzt for the luma. Drum the Picture synonymous s.den critical points OK looks.
2. When combined in video 4 red pixels in a pixel is overdriven, the signal processor übersteurt total. As it were, is a buffer overflow in the luma on the field, the video - pixel is completely white.
3. This overflow occurs synonymous s.den border pixels, but not so strong, so they are still represented by red, but also still override, which in turn brings the DV codec out of step, which then makes blocks.
And the moral of the story: Films not of the red light.
But seriously: I do not think that the cam is broken, in a normal Einchipper this effect would be less likely to occur. The real trick is actually filmed with less contrast, and to avoid such "hot spots" in principle ...
Mella
Antwort von Markus:
Hi Torben,
I can reassure you, the described effect is on DV camcorders (unfortunately) quite normal and occurs even when three times as expensive equipment. Look in the linked post, where I wrote something to the technical background.
If you can avoid situations in which such strong colors bordering directly s.schwarz background, will you these technical restrictions pose no more sleepless nights. ;-)
Link:
Why video images are blurred at a red light?
Antwort von GhostDog:
Thanks for the quick replies.
@ Mella
If I develop your theory next, then I would by a darkening of the image, for example, a shorter exposure time or by a Herabregeln the "Brightness Gain?" E-Lock can reduce the effect. These measures indeed reduce the contrast between the brightness values and actually prevent the overexposure of luminance. This has, however, sees no impact on the actual effect, because with an exposure time of 1/1000s all be like this:
www.neotos.de/downloads/0, 001s_e-lock 0.JPG oddly enough, takes the Herabregeln the E-Lock (color intensity but only if the maximum is) before 0, but this seems in this context does not affect the size / spread of effect to have. See the same theme only with E-Lock -3:
www.neotos.de/downloads/0, 001s_e-lock-3.JPG Even my Opticalmaus there is too much:
www.neotos.de/downloads/maus_0, 05, _elock0.JPG www.neotos.de/downloads/maus_0, 05_e-lock-3.JPG @ Mark
In your proposal you even describe 2 factors:
1. Different Brechindezes compensate for the 3 primary colors and a physical impossibility of this uncertainty associated with certain colors on a lens.
This point can not apply here, since
s.Im Beispielbild 0.001 s_e-lock occurs 0.JPG only one red light source
b) the formed boxes are independent of the sharpness.
2. Weakness of the DV format
What speaks against it:
s.The 4:2:0 color space compression is according to Wikipedia
http://de.wikipedia.org/wiki/ YUV uszur normal television, Mpeg2, etc. used. There are, however, such Rotmuster, as we have here is not to observe
b) I would guess that a DV camera in the larger species, such as this does not show XL2
Why would an error in the processing of these -Codec/der DV Camera:
Even in the digital artifacts are only about 4Pixel high and therefore can not directly come of the recording area, and are therefore not "fehlaktivierten" elements:
www.neotos.de/downloads/zoom1.JPG www.neotos.de/downloads/zoom2.JPG This interpretation is supported by the general behavior of digital zoom, which is reflected in the fact that the noise can be close to the size and number of pixels used and shows, among other things, that the camera has at least 4 defective CCD elements (Optical Zoom: Stable Points , synonymous with absolute darkness, Digital zoom: points are a little bigger and move away to the outside.)
:-(
In all the analysis, do you really think that this edgy! 4Pixel high! Artifacts are really normal and that I (with an XM2 or even XL2) would have still? Somehow I can not believe it.
Regards
Torben
Antwort von mella:
To Rotschwäche the codec I once created the following test pattern:
Above, the original file, below the picture once dragged through the MS-DV codec. (both 200% magnification). As you can see, the DV) Codec (synonymous in software is not particularly good combination with the gray-red.
Picture isses here, I hope it will work, because I did not have a website ...
http://us.f3.yahoofs.com/users/43293326zb331f420/2216/__sr_/d178.jpg?phhjTKDBvpZSJZz.
Mella
If the link does not work, then maybe here
http://de.pg.photos.yahoo.com/ph/mella987/detail?.dir=2216&.dnm=d178.jpg
Antwort von GhostDog:
You're right, I've tried it once and the photos (which were okay), saved in DV format. Looks the same. Is indeed crazy.
If I had this effect synonymous with a camera that saves to Mpeg2? For example, the SonyHDR-HC1?
Regards
Torben
Antwort von mella:
I've tried it once and the photos (which were okay), saved in DV format. Looks the same. Is indeed crazy. That's been ne super idea, I would not have been on it, just take the photo. Because I would have got my can save ollen red and white balls ...
Thanks to your idea you can take your last question actually synonymous answer already. Send your Stillimage Simply drop by an HDV komptiblen MPEG2 codec and look at the m2t stream to. Then synonymous should be clear whether the HDV cams in theory have to do the same "mistake".
And please let us know the result then synonymous:)
Regards
Mella
Antwort von GhostDog:
Yes, that is in wmv and in Mpeg format does not occur in HDV, I have not tried it, there are no longer visible in the standard resolution for these effects.
Thank you for your help, now I can again (some) :-) sleep. The pixel errors are synonymous gone again, seems not to be the camera for more than an hour to run s.Stück.
Regards
Torben
Antwort von Markus:
In your proposal you even describe 2 factors:
1. Different Brechindezes for the 3 primary colors ... Hi Torben,
with the different refractive indices forget. In the linked post, I had only taken up the theme of the previous speaker, which for the described artifacts is not responsible. Aberrations within the optics are often pixilated! ;-)
Also, the image intensifier in the camera does not generate this error. That is correct. Fluoroscopic first create an uncompressed picture.
2. Weakness of the DV format
What speaks against it:
s.The 4:2:0 color space compression is used according to Wikipedia uszur normal television, Mpeg2, etc.. There are, however, such Rotmuster, as we have here is not observe. You're comparing consumer with professional equipment. DV is a consumer format, and there are next to the price a few other differences ... ;-)
b) I would guess that a DV camera in the larger species, such as this does not show XL2 Then I would now bet anything against it. Even the Sony DVCAM series created these aberrations. I once recorded a number of candles, lit with the pure blue light were:
Antwort von GhostDog:
Yes, the DV format is put on a consumer format, but the cameras themselves for 4000 ¬ (DSR-PD170,
http://de.wikipedia.org/wiki/ DVCAM) to such a format that puts the halt such "consumer behavior" s.den day, I did not expect halt. It is not explained in this regard so synonymous of sellers, magazines, or "Ottonormal filmmakers," unless one pokes into the causes.
Well, and those who know to stop buying such an expensive semi-professional camera for a few thousand euros, what they can expect and expect. On the other hand do most of the people there probably do not synonymous head upward, as it's not noticeable on a standard TV anyway. But with the HD (T) V-evolution movement does seem to come into the matter.
Just a pity that there are no patches for the cameras at times to teach another alternative, Proprietary Record format :-)
Regards
Torben
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Antwort von Markus:
Hi Torben,
without these restrictions are very high quality video formats (-> from 4:4:4), but who can / want to afford to have only (!) to synonymous in extreme still make very good pictures?
Despite all the prophecies of doom: I think the DV - DVCAM format and easy class, especially when one considers the price-/Leistungsverhältnis. And fortunately, the extreme situations described occur rarely. On Television formed synonymous out any pixels as the computer monitor, but the area looks utterly blurred. Layman such defects usually pay no attention, while angry ambitious videographers, and professionals have views about it. ;-)
