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-   -   VISIBLE NOISE !! - CHOOSING a LARGE FORMAT LCD SCREEN for PRE-VIEWING HDV (http://www.dvinfo.net/forum/canon-xh-series-hdv-camcorders/105517-visible-noise-choosing-large-format-lcd-screen-pre-viewing-hdv.html)

Shawn Levin October 12th, 2007 04:07 PM

Hi to all of the A1 tribe !

I went out today with my XH-A1 to test a few LCD SCREENS for viewing HDV.
I want to use the LCD as a preview screen for showing HDV in my edit studio.
At the moment I am still shooting & editing SD, but want to make the move over to HD (slowly !)

My thoughts were to 1st buy an LCD screen so I could at least see some HDV testing footage from my cam.
I have not yet used the cam in HDV mode at all.

So..... a few questions.

I went to a few stores and plugged in the supplied HDV COMPONENT VIDEO CABLE
I tried 37" - 42" LCD screens of brands SONY, PANASONIC, SAMSUNG.

The first thing I noticed was the apparent noise @ +3dB gain....
I was somewhat surprised, though I do realise that HD requires much more light than SD.

As I moved through my 3 gain settings (L=-3dB M=0dB H=+3dB)
I noticed quite a lot of noise. I thought it unusual..... I mean +3dB is hardly pushing it - right ?
Of course ND & AGC was off and I simply has the cam in Automatic mode....
output was set to 1080i......all seemed fine except for the noise.

The 3 department stores I tested the LCD's where lit much the same,
flourescent lights (a lot) , no daylight.... I guess the same as your department stores over there (wherever you all are) (BTW I'm in Cape Town S.A.)

Could you guys help with some of your experience with regard:


A--- NOISE---
1) Is this normal ? very noticable noise at 0dB and +3dB
2) What is the MAIN source of the noise ?
Is it the Cam, screen or could it be the component output?
3) Would an HDMI output be more 'noise free' (though the A1 doesnt have one)
4) Those of you editing in real time HDV what preview output do you have from your PC or hardware cards ?

1) Do I need to buy a FULL HD LCD 1920x1080
or is 1366x768 good enough (It looked good enough to me
(except for the noise at +3dB)
I believe the native HDV resolution of the A1 is 1440
2) The SONY WEGA looked the sharpest it was 40" (most expensive though !!)
and PANASONIC with hi contrast (8500:1) was also good - (a 32")

There are so many factors that affect the pic on the various LCD SCREENS:
resolution, pixel size, contrast, physical screen size etc etc.

Sorry for the multiple questions all at once !

Any other advice/information in these respects would be appreciated.


Chris Soucy October 12th, 2007 04:51 PM

Hi Shawn.............
The TV sections of Deprtmant stores run a pretty low light level, to best show off their screens. Not a good place to be shooting HD.

Running the anamorphic 1440 X 1080 O/P (it plays as 1920 on a screen - just think: A1 = 1920) from the A1 into a less than Full HD (1080) screen means the screen has to scale the picture. Some do this well, some not so well and some are, quite frankly, awefull. Not so well & awefull can give the impression of more noise than is really on the source material.

So, you have iffy source material and scaling artifacts already going against you.

My suggestion?

Go out, shoot some HD in good conditions and get to know how the camera handles under various circumstances. A good way to really see what's happening with Gain levels is to mount the camera on a tripod in decent light, shoot a scene (any scene) starting @ -3 and speak at the same time giving the details of camera config. Go to 0db, +3 etc. Do the same in a slightly less well lit situation. Repeat till you've "got the picture".

Take the camera back into the store(s), test only 1080 screens, plug in the component & audio cables and fire it up. In my experience it's about then you will get the un - divided attention of just about everybody within a 10 metres radius.

I don't know your home viewing circumstances, but as a guide to size, my 46" Sony 1080 screen sits on the other side of the room from my NLE system. It's about 2.6 - 3 meres away and is just about perfect.

If you go for a smaller resolution screen you will need to sit further away from it, as the pixels are larger than those of an identical sized 1080. The less the resolution, the further you need to go.

I run my screen (when using the NLE) using the Component O/P from my Matrox APVe card - unfortunately the DVI off the Matrox will not work with the HDMI of the Sony (do NOT let a salesman tell you "they all will" 'cos a lot don't).

Works from the DVI off my laptop, but the laptop can't do the resolution necessary.

Using the HV20 with HDMI to the Sony is about as crystal clear as you can get - noticeably better than the Component, which is no slouch in itself. I use this to "log content" before loading into the NLE for editing and gee, it looks pretty.

IMPO, if you are thinking of ramping to HD and getting a screen to match, going for less than "the real deal" is like owning a car and pushing it 'round town to save on gas!


Shawn Levin October 12th, 2007 05:48 PM

Chris ....Thanks for the quick reply and all your input and suggestions, I will go shoot some HD in acceptable lighting conditions and use this footage as demo for the LCD test.

The full HD (1920x1080) LCD's are really expensive here..... they are still flooding the market with 1366x768 screens....
a SONY 1920x1080 42" is about R33 000 (rands) equivalent of almost $5000.00
40" SONY 1366x768 is about half the price....
I hear what you say about going the 'whole hog' and doing it properly, but the lower res SONY looked pretty good res (just the noise at +3dB bothered me) at 0dB or -3dB it looked great.

I thought the XH-A1 = 1440x1080 : so the 1920 LCD would have to scale this UP ?? or does the cam create a pseudo 1920 horizontal resolution output ?

I too am running a matrox suite here (SD of course) (not so popular in S.Africa) but I have been using it for a few years now and it has worked well.
(I'm considering moving over to mac !)

Does the standard HV20 have HDMI output ?

HOW does HDV output from mac ??
and those using PC..... are you guys using hardware cards.... I hear some people with AVID on PC and NO hardware..... how is the HDV output for preview - and are you guys simply using these kind of LCD TV screens for preview monitors ?

Thanks guys

Chris Soucy October 12th, 2007 07:22 PM

Hi again.
Yep, the "real deal 1080" screens are exxy everywhere. It's not a game for the poor, tho' an "el cheapo" way of getting 1080 is to kit yourself out with a Dell 24" LCD monitor (or similar) which has just about every type of connect going and even has HDCP on the DVI port.

The downside is that, although it makes for a great PC monitor, and the resolution is great, the colour is not. There are work arounds however.

You could get one of those AND a cheap semi HD telly, just to keep an eye on "real" colours (be a few that will disagree with that one!).

You're sort of right with the A1 "pseudo" 1920.

The HV20 has HDMI straight out of the box.

Can't tell you much of anything about Macs.

Not sure I followed the last paragraph enough to comment.


John Arnold Ph.D. October 12th, 2007 08:15 PM

Monitor or TV
I just bought the Gateway 24" 1920x1080 as my monitor and find the colour and resolution to be excellent. That was a month ago, and it is $150 less today.
Costco Canada is selling the Viewsonic 42" full 1080P television for $1199 Canadian which in comparison to a side by side Sony Bravia 1080P is better in my opinion. A friend just bought one a week ago for $1249--the price is dropping like a stone and I took my A1 over for viewing some outdoor footage--outstanding colour and resolution. It seems as sharp as the 60P cameras used for Major League Baseball on HDV. I have had for several years a Sony 36" Bravia CRT which weighs over 200 lbs. and although I cannot compare it to the Viewsonic side by side, I believe that the Viewsonic colour gamut is just as good.
If you have a choice, wait a bit longer for the prices to plunge.

Chris Soucy October 12th, 2007 08:33 PM

Hi John.................
Think it's going to be a while before us "boon dockers" see prices like that, more's the pity.

But you are correct, the quality keeps getting better and the prices are falling, just slower in some places than others.


Shawn Levin October 13th, 2007 04:27 AM

Thanks for the replies....

2 more questions please :

1) anyone using lower res LCD TV as preview monitor ....
I'm looking at SONY BRAVIA 1366x768 40 " (looks good to me)

2) what are the output terminal options to preview in real time for mac
is it HDMI (for example on mac pro)

Those of you editing in HD on PC are you using realtime video editing cards
like matrox Rtx2 ??


Jerome Cloninger October 13th, 2007 09:00 AM

I think when people notice noise and complain about noise, they are sitting right in front of the screen. Move back to normal viewing distance and you should be pleased. Even on a 1080 model, sitting 1 foot from the screen is going to be noisy... its not like seeing a photograph.

Bryan Gilchrist October 13th, 2007 03:17 PM

I got an Element FLX-1910 which has an HDMI input, composite, VGA, COAX and S-Video input. It's inexpensive and great for field use. And, when it's not in use in the field, I use it to watch TV in my edit bay. :)

I also got a LCD monitor mount and stand from Markertek (http://www.markertek.com/SearchProdu...ff=5&sort=prod) that I put the Element on so I can use it for a field monitor when out on shoots.

The 1910 supports 480i, 480p, 720p and 1080i. It can be found at Sears, Circuit City, Best Buy and others for under three bills. Not bad for a 19" HDTV/VGA Monitor.

Bob Drummond October 15th, 2007 12:00 PM

Another thing to keep in mind is that electronic stores usually have their TV's set to absurd, overblown settings. They are nowhere near properly calibrated via something like Video Essentials. If you jack up the color and the detail on a set, you're going to see noise in almost any signal.

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