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-   Canon XH Series HDV Camcorders (https://www.dvinfo.net/forum/canon-xh-series-hdv-camcorders/)
-   -   Getting rid of noise (https://www.dvinfo.net/forum/canon-xh-series-hdv-camcorders/85066-getting-rid-noise.html)

Tony Tremble January 30th, 2007 05:12 PM

Quote:

Originally Posted by Stefan Koler
Is there someone who owns an A1 PAL version, and has no problem with noise?

I have an A1 in PAL land. Noise is not a problem.

TT

Holly Rognan January 30th, 2007 06:16 PM

Your probelm in the closed iris. Put an ND on, don't use 8.0 or higher, you will get grain.

Richard Hunter January 30th, 2007 06:20 PM

Quote:

Originally Posted by Jeremy Naus

PS: I just saw that in firefox the images are really dark.
I'm working on a Mac and on my screen it all looks bright (and also on viewfinder it looks bright). I captured it all in iMovie. (am saving money to get FCP)

Hi Jeremy. If this image looks bright on your viewfinder, I suggest you adjust the settings. The best way is to hook up the analogue video output to a TV monitor (preferably a calibrated one) and adjust the viewfinder brightness and contrast until it is a lcose as possible to what you see on the monitor. This will not give you exact settings, but it will be pretty close and will allow you to trust the viewfinder better.

Also, you can use the zebra bars to help avoid blowing out bright areas that you want to keep detail in (although you won't have that problem until you fix the underexposure :) ).

Richard

Jeremy Naus January 31st, 2007 02:44 AM

Quote:

Originally Posted by Tony Tremble
Why f9.5 ???

Easy reason: when I look at the lcd screen on the camera it looked much much brighter than what I see on my pc here at work.
Remember, I'm running OSX at home and there it looks as bright as the lcd of the camera.
Now I googled a bit and found out that OSX does colors differently. So I'll have to check to see that my OSX screen uses the same color settings as a PC.
So while I solved the reason why it looks bright on my Mac I'm still wondering why it looks so bright on the LCD screen of the camera (I didn't change the LCD settings).

EDIT: just read Richards answer. I'll try that out. Thanks, I hope this will solve my noise problem. I did find it strange that I had to use f/9.5 to make it not to overbright :-)

Jeremy Naus January 31st, 2007 02:47 AM

Quote:

Originally Posted by Holly Rognan
Your probelm in the closed iris. Put an ND on, don't use 8.0 or higher, you will get grain.

What is an ND?

Tony Tremble January 31st, 2007 03:28 AM

ND = Neutral Density filter.

You wouldn't have to use F9.5 if you had engaged one of the two ND filters you camera has built in.

***Read your manual thoroughly***

I use OS X and that is no excuse for not being able to use your cameras controls effectively. Under or over exposing has nothing to do with which operating system you use.

TT

Jeremy Naus January 31st, 2007 03:43 AM

Sorry Tony, but when I see on the viewscreen of my camera a bright garden, and I see >exactly< the same on my OSX screen, then I'm thinking that both are giving me really a true image. Yes, I was wondering why I had to use F/9.5 (cause I never go higher than f/6 when I take pictures with my EOS10D), but the viewfinder showed me an overbright image, when I use anything lower than f/9.5
Then I see my clip on a PC and it's suddenly dark. When I googled I read that OSX handles screen colors differently than a PC (or a TV). So what I see on my OSX monitor can be different than what people would see on a PC screen (I tested this with an image that was very colorful in OSX and very dark on a PC).

And again: I was testing the dvinfo presets, so I didn't want to change any filter settings, only aperture and shutterspeed.

But as Richard told me, I'll try calibrating my viewfinder to make it give me a "true-er" image. And I'll also calibrate my monitor under OSX.
If I had seen that the clip was dark on the viewfinder and/or on my mac screen, then I would never have asked the question here. I would've known I had underexposed my scene.

Anyway, when my viewfinder is calibrated and also my osx monitor, I'll have a try again this weekend and I'll let you people know if I still have the noise.

Bill Busby January 31st, 2007 04:13 AM

Not that the LCD screen or CVF is going to truly show you exactly what the image is... but you CAN get it as close as possible in regards to brightness easily.

Try viewing your LCD screen "dead on" (no tilting). Use your color bars & adjust the pluge pattern (the three dark bars at the lower right... superblack, black, and gray. Adjust the LCD brightness until you can just see the gray bar & the superblack and black blend together & there's no difference between them.

Do the same for your CVF.


If you've already done this and/or already knew this, my apologies :)

Something just occured to me. Where's the "blue only" for better calibration? Ahemmm... new firmware wishlist addition :D

Bill

Jeremy Naus January 31st, 2007 04:15 AM

Bill, thanks for the info, I'll try that too :-)

Tony Tremble January 31st, 2007 04:25 AM

Jeremy

Read this article on the use of colour bars.

http://www.videouniversity.com/tvbars2.htm

It will take through the process of setting up your LCD, VF and computer displays to match.

Flick the Bars switch on the camera and go from there.

Hope that helps.

TT

Jeremy Naus January 31st, 2007 04:35 AM

Tony, thanks for the info :-)

Vincent Wong Yoon Wei January 31st, 2007 04:42 AM

They put the zebra function there for a reason. The LCD and VF are decent methods to gauge your exposure if you are familiar with them but zebra is really your best pal to tell you if your exposure is correct.

Mark Fry January 31st, 2007 06:43 AM

While I'm getting used to the XH-A1, I have been using the auto-exposure modes as a starting point. I've done a few experiments comparing Auto and manual settings, including some sunset scenes with very bright sky and very dark shadows, and the Auto settings are pretty sensible.

You say you like to stick with 1/50th shutter speed (sensible), so try the Tv (shutter priority) mode, select 1/50th, and then press the Exposure Lock button see what the auto-exposure thinks the apperture should be. You should see the f-stop setting displayed together with a line with an arrow above, which is a sort of a light-meter read-out. The middle of the line is what the auto-exposure considers "normal", and the arrow indicates how under- or over-exposed the picture is. You don't have to accept the auto's settings, but it gives you a reference point.

Jeremy Naus January 31st, 2007 11:23 AM

Shot a new scene this afternoon (thank god the days are getting longer again :-) )
I first 'calibrated' my lcd viewscreen using my tv as a reference.
The aperture is now much lower (don't remember the exact setting though)
Shutter is in the first half at 1/120 (or higher can't remember) and in second half it's 1/100

I think the result is much better now
http://www.banapsis.eu/downloads/Noise2.mov

Steven Dempsey January 31st, 2007 11:36 AM

I'm glad this is looking better for you. It still looks like you have the NR filter on. I would definitely not use that because it turns detail into mush.


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