A friend who works with a community arts project recently asked me whether she was making a mistake buying a DV camcorder (she had earmarked the 3 chip Panasonic NV-GS500) rather than an inexpensive HDV camera such as the HV20 for student use. The camera will be used for a wide variety of experimentation with video.


I've mentioned all the obvious advantages and disadvantages of HDV which came to mind such as long GOP, potential low light weakness, greater computing resources needed for editing and risk of mpeg compression artifacts vs. HDVs higher resolution, 24p recording and buying into what is becoming the de facto standard for many users.


What I am unclear about is whether there is any marked advantage in choosing a 3 chip DV camera in this price bracket over an HDV camera with one chip CMOS sensor. i.e. What would a side by side comparison between the 3 chip SD footage vs. downsampled 1 chip HD footage from the HV20 show? I suspect much of the footage will end up being output at either PAL res or for the web.

Also, what is the colour rendition of the HV20 like and on cheap HDV cams in general?

The 2 cameras are almost exactly the same price.

The single chip CMOS sensor shouldn't be considered automatically inferior to a 3 color CCD. # is not always better than 1 ... in this case its and apples to oranges comparison.

In my limited testing so far, I've found the HV20's color to be pleasant and natural, though I haven't charted it to see if it is technically "accurate."

With even iMovie able to edit HDV footage, I'd definitely go that route. When you down-sample HD footage to SD, the perceived sharpness is so much more than that from a SD sesnor.

See my post at http://www.dvinfo.net/conf/showpost.php?p=720254&postcount=4

Single-chip with RGB (such as the HV20) equals 3CCD color.

Roddy, please read this thread:My Canon HV20 vs. JVC GZ-HD7 experience (http://dvinfo.net/conf/showthread.php?t=91005)

HV20 with 1CMOS is better than more expensive HDV camcorders with 3CMOS(CCD).

It's much as I suspected. The HV20 sounds excellent and as it turns out, the organisation in question couldn't get the Panny so I'll have a chance to play with the Canon tonight. Very excited!

I will be interested to see if the case is as 'plasticky' as some people have hinted. Equally, I'll be interested to know if the HV20 is sensitive to near IR or if there is some kind of filtering limiting the usefulness of an IR illuminator.

Any experience of this?

Very glad to finally have posted something on DVInfo. Good friendly advice really does beat spec laden reviews sometimes.

Thanks fellows.

-Roddy

For further reading

http://www.dalsa.com/markets/ccd_vs_cmos.asp

Very glad to finally have posted something on DVInfo. Good friendly advice really does beat spec laden reviews sometimes.(Especially when those spec laden reviews tend to be incredibly inaccurate).

That's the difference we're trying to make here -- much appreciated and welcome aboard!

check out this image showing the difference in sharpness between SD (standard DV) and HDV downressed to uncompressed 10bit

http://file.meyersproduction.com/hv20/Downrez%20comparison.png

I think I found a way to minimize blocking artifacts in HDV blacks. I would like to explain and if someone try it, let me know.

1 - put the same m2t footage aligned in two video tracks in Adobe Premiere.

2 - in the upper track apply gaussian blur and adjust between 4 and 6. (adjust looking the blacks)

3 - in the upper track apply arbitrary map and adjust between -5 and -1 (adjust looking the blacks)

4 - in the upper track apply luminance key (adjust the key to keep only the blacks of the upper track over the lower track, be carefull to not get color fringing in key edges)

5 - render to uncompressed.

The goal is to minimize the blocking artifacts in the blacks where HDV compression is more visible.

If someone try this, let me know.

Thanks.

Yeah, that should help soften macroblocking in shadows. You could also use a few differnet filters made specifically for removing noise and leaving detail.

Here's one:
http://www.revisionfx.com/products/denoise/

Nattress is another. And there are others made specifically for DV/HDV artifacts, as well. With some of these you get added benefits, like smoothing the lack of chroma resolution.

To be honest.. It's not really about the camera's quality as much as it's about learning.. Student? When I was learning how to handle a camera it was best that I dove in and was handed a camera which had many manual controls to learn with and few auto controls to force me to use it and learn it to know what does what and how it all works. The HV20 is great and IS a consumer camera. BUT, really.. You have to know your stuff to get the most out of this camera. This is not a camera to really start off learning on imo. But, for 1,000 bucks your crazy if you are holding that money in your hand with nothing to spend it on while looking at the HV20 saying to your self; "well... I dunno..."

1 chip or 3 chip.. Dammit! Give me a 1,000 chips and a soda to wash it all down. People are too caught up in this. It's Intel vs Athlon all over again.

With regard to your question about IR, the HV20 can pick up the O/P of an IR remote control, which I guess means it will, indeed, be usable with an IR illuminator.

As for the case feeling "plasticky", don't know where you picked that up from, it's a chunky solid piece of kit, exceedingly well engineered. Nothing "plasticky" about it to my mind, but I guess that's in the eye of the beholder when all is said and done.

I actually think my A1 is more "plasticky" than the HV20. Hope you enjoy yours.

CS

Well, experimenting with the HV20 has turned out to be a lot of fun. It is of course a far cry from my XM-1 in terms of manual control but it is after all meant to be a consumer camera. Having said that, the image quality really is peachy. Until I can afford the XH-A1 I think I'm going to get myself one of these (and perhaps a Brevis to boot :-) ).

Thanks for the link concerning CMOS vs CCD. As for the IR sensitivity, I'll be very interested to see just how sensitive it is.. Now that I'm finally buying a compact camcorder, I'd love to try filming surreptitiously in very low light situations where pulling out an XM-1 might not make people too happy.

-R

Hey Roddy, I just got the HV20 to use with a Brevis adapter also. I'm waiting on the Cinevate 72mm achromat to show up at the present time. The footage that I have seen on the web so far with the HV20/Brevis combo is just beautiful.

Steve, congrats!

I own the same setup - achromat as well. I found a spacer helps, but it depends on what lenses you're using with your setup. What lenses will you be using?

Steve, congrats!

I own the same setup - achromat as well. I found a spacer helps, but it depends on what lenses you're using with your setup. What lenses will you be using?

Hello Robert. The only lens that I have to work with at the present time is a Nikon (Nikkor) 50mm f1.4. Soon I'd like to get a decent telephoto and maybe a wide angle.

What lenses are you using with the spacer?

When I finally get the Achromat, I need to sit down and read all the notes on the "Cinevate forum" about using the HV20 with the Brevis.

One disadvantage of the 1 chip CMOS sensors is the sequencial scan from top to bottom. Since the lines at the top are captured earlier than the lines at the bottom you can get some interesting distortion.

In all fairness, this does not show up under most shooting conditions.

Two examples under which the distortion artifacts are very obvious are:
1. Filming out the side window of a car. Telephone poles will be slanted. You may not care about this but be sure to force the camera to a 1/60 shutter speed to minimize the effect.

2. If the camera is moving up and down in angle and this is more than the OIS can completely take out, you get some of the image compressed and some of the image expanded and since this happens differently on every frame the effect is very obvious and very distracting. Image stabalization won't help you here. The worst case I have run into on this is taking video looking our the side of a small boat/ship when there was a little rolling motion. The video was completely unusable, even when down sampled to SD. Obviously, the effect is much worse the more you zoom out under these conditions.

Rick

For me, the advantage of shooting in HDV, then downconverting to SD during editing is that, because the resolution of the HD is higher, I can crop and correct framing mistakes without the typical visible loss of resolution when cropping SD.

HD has made my poor sense of composition much finer...

One disadvantage of the 1 chip CMOS sensors is the sequencial scan from top to bottom. Since the lines at the top are captured earlier than the lines at the bottom you can get some interesting distortion.

Rick

"Some interesting distortion" you can get from 3CCD camcorders also:

http://www.fxsupport.de/pic/07/08/11/k02.jpg

Read more in Wolfgang Winne blog. (http://babelfish.altavista.com/babelfish/trurl_pagecontent?lp=de_en&trurl=http%3a%2f%2fwww.fxsupport.de%2f25.html)