Does XH-A1 Smear Light Too Much?...

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dr_bernie

Member
Hello All,

I am new to this forum. I have been reading posts for quite some time to try and decide between XH-A1 and Sony HVR-V1.

So far I am leaning towards XH-A1. But I have seen this footage

http://youtube.com/watch?v=GGB3z0LTR-g&mode=related&search=

of an XH-A1. About 50% through the footage there is a shot at traffic lights with obvious smearing effects. And when one of the lights turns green, it looks like anything but a traffic light!

My question is: Is this the way XH-A1 behaves, or is it a matter of
the camcorder not properly adjusted?

By comparison if you look at this footage of HVR-V1

http://youtube.com/watch?v=03gvhrpzUPg&mode=related&search=

There seems to be a lot less light smearing. About 30% through the footage there is a direct shot at sunlight and it is surprisingly crisp and clean.

Note I don't want to turn this into a heated rhetoric on XH-A1 against HVR-V1. I only want an answer, if at all possible, to a simple technical question.

Thanks All.
 
The answer is that CMOS chips don't smear, and CCDs can. What you showed isn't really smear though in the XHA1. Smear is when there's a big vertical line through the frame, caused by a too-bright light. All CCD camcorders are subject to something like that happening; the smaller the pixels the more likely it is to happen.

Look at the vertical smear from this headlight, from a Sony FX1:
FX1%20vertical%20flare%20from%20headlight.jpg


That's an example of CCD smear. You shouldn't ever encounter that particular artifact on a CMOS camera.

CMOS vs. CCD is quite the debate; in bright light conditions CMOS does very well but in all the existing cameras CMOS is nowhere near as light-sensitive as CCD is. CMOS cameras can suffer from the rolling-shutter shear (where a vertical object appears to "lean" as you pan side to side) or in the worst case, the "wobble" (as seen in many recent HV20 postings here). CCDs won't be exhibit either of those artifacts. But CCDs can smear.

Six of one, half dozen of the other, neither technology is perfect.
 
dr bernie. I have used both the A1 and V1. There is most definetley a smear on the A1 and as Barry pointed out it is relative to the CCD.

Now as you are trying to decide which camera to buy. Id hope to save you a little heartache. The V1 has another issue - heavy macro blocking. This can turn up anywhere in your mids and darks. My experience has been somewhat inconclusive as to the cause and my desire to to actually understand it is rather low, though I can say this, I have seen it in virtually any color. Suddenly you come across an area which looks just like bricks within a particular area, again mostly in the mids and darks.

Do with that info what you will. Im just telling you what I experienced.
 
dr_bernie said:
Thanks for your feedback ncje. It is not clear to me which camera you are talking about for the macroblocking issue? The XH-A1 or the HVR-V1? You mention the V1 but I have the impression you meant A1. Please clarify.

Please watch the following footage. It has a good example of macroblocking, but it is an A1.

http://www.youtube.com/watch?v=NDkbaSH3TDA&mode=related&search=
Click to expand...

I was talking about the Sony V1. If it were the A1 I can tell you mine would have gone a long time ago.

There is compression artifacts in that clip. Not the fault of the A1 but how it was compressed for youtube, virtually every clip on you tube has it.
 
Wait, let me get this straight, your complaining about macro blocking from a clip you see on youtube? Come on :(
 
scharky said:
Wait, let me get this straight, your complaining about macro blocking from a clip you see on youtube? Come on :(
Click to expand...

Yeah, but he's right. It's totally blocky and stuff.

I also saw an animated gif of a 30 second clip, also shot on the A1, and I thought it was a little...choppy. So I'm gonna sell my A1.
 
Bernie I wouldnt judge any camera by looking at its compressed output. I can take footage out of any handycam and apply some decent compression to it and put it on youtube and I can take my HVX footage and put some poor compression on it and put it on youtube and the handycam will look 20x better. You need to be looking at footage from both either uncompressed or at the least under some good compression like a high bitrate quicktime in its native res. Both cameras produce a good image. I'd compare price at features at that point. To me good footage is usually produced by good lighting and I'll be damned if my camera is any good at lighting a scene...
 
Thanks ncje and jdajda for your answers. I knew that compression affects the picture resolution, but I wasn't aware that it affects the lighting as well.

Thanks again.
 
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