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-   Sony HVR-V1 / HDR-FX7 (https://www.dvinfo.net/forum/sony-hvr-v1-hdr-fx7/)
-   -   noise in V1: stirring up a hornets' nest (https://www.dvinfo.net/forum/sony-hvr-v1-hdr-fx7/87227-noise-v1-stirring-up-hornets-nest.html)

Piotr Wozniacki February 22nd, 2007 06:30 AM

noise in V1: stirring up a hornets' nest
 
After spending a lot of time comparing the quality of video from the V1E and Canon XH-A1, an idea occured to me: I played back my old footage from the Sony HC1 I sold half a year ago due to it's simplistic design and poor low light performance. I played back a film I shot in the summer, so there was plenty of sunshine. After getting used to the footage from those higher class, "professional" cameras, I was shocked: there's no noise at all in the HC1 footage, even in darker areas of the scenes! Neither the V1, nor the A1 (with its -3dB gain setting) is as clean in terms of noise as the HC1.

Add to it that the HC1 doesn't show any CA (so obvious in the A1) or barrel distorsion, and here I am, feeling like a fool...

And I'm not joking, in case anyone have suspected. True, in low light the HC1 picture deteriorates quickly - the perceived resolution drops, and the image is blocky. But there is no noise! You simply get a quite acceptable, SD-quality footage. While with both the Sony V1 and Canon A1 there is this "dancing noise" almost everywhere except the super-lit areas. What the heck?!!

Zsolt Gordos February 22nd, 2007 11:26 AM

Hi Piotr,

do you have the V1E unit from the "new batch" already? Have you started the testing? I am very curious...
Currently I shoot in i - pretty nice results so far, but I would consider bugging Sony for a replacement unit if the new batch turns out to be flawless.
Please keep us posted.

Piotr Wozniacki February 23rd, 2007 03:21 PM

UPDATE: what I was calling "noise" in the V1 is not the same noise that we deal with in most HDV cameras, especially in low light situations when gain is engaged. I've done a couple of tests with the V1E in progressive mode (when the "noise" is most visible), all in good light, but with various sharpness setting. It turns out that what I considered "noise" is actually yet another artefact, introduced into progressive image when the sharpness is at the default 7 level or higher. This is consistent with what Prime Support has been advising the PAL V1 version users ("to turn the sharpness down in order to avoid line flicker"). Now, this phenomenon is best described as "dancing pixels" (thanks Steve Mullen:) It is most apparent around contrasty edges, and can be virtually eliminated with sharpness at 3. The overall picture gets a little too soft then, so IMHO the best compromise is to use sharpness at 5 (unless the soft, "filmic" look is actually desired, when sharpness 3 is perfect). Comparison shots can be found here:

http://rapidshare.com/files/17910475...arpness7-3.m2v

Bob Grant February 23rd, 2007 04:51 PM

Going back over some test footage I shot a few weeks ago this is exactly what I'm seeing also. But there seems to be more to it than that. I was using a board covered with a coarse weave light brown fabric to hold a few pieces of white paper.
The pattern in the fabic does some interesting things, it seems like where there's enough light the fabric has little to no noise and detail. Then as the light falls off the detail level drops. When the light drops further the detail is back along with serious dancing pixels.
As you've also noticed the noise gets worse near high contrast edges also.
I've also noticed similar interesting effects taking the component output straight from the camera's "head" into a monitor.

Dave F. Nelson February 23rd, 2007 07:52 PM

The lack of noise on your camera, I can not explain. I used to have an HVR-A1U and shot quite a bit of footage. I found the noise to be unacceptable. I shot the fireworks last July 4 and the footage was so bad that I recycled the tape.

The lack of CA is due to the fact that the HC1/A1U has a marginal quality lens that produces a very soft image. The little 38mm lens can not resolve sharply enough for CA to manifest itself in a big way like cameras with sharper lenses.

I sold my A1U right after the shots I took last July 4th. The camera is sub-standard compared to my Z1U and XL-H1.

It is difficult to make comparisons between camcorders with decent lenses and the HC1/A1U or any of the other newer HD camcorders with 38mm lenses.

Just my humble opinion.

William Gardner February 23rd, 2007 08:40 PM

My 2 cents as an owner of both an HC1 and a Z1U:

In good light, particularly in daytime, the HC1 is quite clean and close in quality to the Z1U used in all auto mode 60i, although the color is a little different (particularly the reds).

In bad light, the HC1 is noisy and the autofocus is slow. It also suffers from the rolling shutter effect during quick changes (like flashes, quick pans, or fireworks :).

I think that fireworks are probably one of the most impossible things for an HC1 or an A1U to shoot, and I can see why Dave would get rid of it if he needed to shoot fireworks, night shots, or dimly lit indoor shots a lot. However, it does work quite well for daytime shots where the light is abundant. I have used it as a B camera for a Z1U daytime shoot and I intercut a few seconds here and there without anyone noticing.

BTW, Dave, I'm also in San Diego. Would love to know more about where you are and what you do...

Bill

Douglas Spotted Eagle February 23rd, 2007 08:42 PM

Quote:

Originally Posted by Dave Nelson
The lack of noise on your camera, I can not explain. I used to have an HVR-A1U and shot quite a bit of footage. I found the noise to be unacceptable. I shot the fireworks last July 4 and the footage was so bad that I recycled the tape.

The lack of CA is due to the fact that the HC1/A1U has a marginal quality lens that produces a very soft image. The little 38mm lens can not resolve sharply enough for CA to manifest itself in a big way like cameras with sharper lenses.

I sold my A1U right after the shots I took last July 4th. The camera is sub-standard compared to my Z1U and XL-H1.

It is difficult to make comparisons between camcorders with decent lenses and the HC1/A1U or any of the other newer HD camcorders with 38mm lenses.

Just my humble opinion.

Two comments...
It may well be that you didn't have enough training or information to use the A1 to the best of it's abilities. It definitely is a clean camcorder in its class.

My XLH1, Z1's, V1's are all substandard compared to our XDCAM and F700 too.
It's all about what you can afford. Bang for buck, the A1 has been a great camcorder, but you can't cross camcorder classes by suggesting the A1 is in the same category as an H1, V1, Z1, or JVC HD200U. It's apples to Chevrolet's.

Mikko Lopponen February 24th, 2007 06:47 AM

Quote:

Originally Posted by Dave Nelson
The lack of noise on your camera, I can not explain. I used to have an HVR-A1U and shot quite a bit of footage. I found the noise to be unacceptable. I shot the fireworks last July 4 and the footage was so bad that I recycled the tape.

I've shot fireworks with the hc1 and they've looked very nice. Just don't use automatic settings and LOWER THE GAIN!

Quote:

The little 38mm lens can not resolve sharply enough for CA to manifest itself in a big way like cameras with sharper lenses.
No. It's because it isn't nearly as wide or tele as the A1.

Marcus Marchesseault February 24th, 2007 07:19 PM

Don't forget that the V1 has black compensation that can totally eliminate noise in the blacks, even if a touch of gain is used. I think fireworks at 1/30th shutter 30p with black compression on would look fantastic. A bit of motion blur looks great with fireworks and no gain should be needed.

I see what you mean by "noise" in the clip and I don't get that with the V1U. I have seen that on broadcast television with clips downsampled from HD origination sent to SD broadcast. I just can't get my mind around how Sony could suddenly have a camera that doesn't look as good in PAL as NTSC. This isn't the first camera they've produced.

Zsolt Gordos February 26th, 2007 02:26 AM

I have shot quite some with my V1 in low light conditions of night street shows with neon light decorations. Similar situation to the fireworks.
I am on my way back home from traveling, I will post some clips soon.
My earlier low light clips looked nice with black compress. I saved those setting as picture profile and this time used this profile with adjusting gain only.


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