View Full Version : How to check for possible faults in new GL2


Michael Murray
June 5th, 2003, 11:47 AM
After following this forum carefully for weeks and doing my own research, I felt confident in buying from Zotz and yesterday I received a new GL2 from them.

Zotz gives you 30 days to return faulty gear. As a newbie it could take me longer than that to notice a problem.

Reading about new camcorders with 'hot pixels', 'dead pixels' etc, suggests I should look it over very carefully. But how?

Can you please tell me if there are specific tests I should run, or what one should look for, to make sure everything is as it should be.

Thank you.

Vladimir Koifman
June 5th, 2003, 01:56 PM
You can check for dead pixels if you shoot with closed lens cap with fast shutter speed, say faster than 1/50. Then look if whole screen is completely black, whithout white or color points. Any single point in this screen means dead pixel.
It's good to look for them once you import your video into computer, as you can see full picture area, including the portion that usualy hidden on TV.
Then you can shoot a white surface in a very good light and check for black or colored spots, that constantly present on the same place. These are dead pixels as well.
Hot pixels appear at slow shutter speed only. To check it, repeat the first test with slowest shutter speed possible. The hot pixels might be more visible in hotter environment. Also, one should differentiate hot pixels and noise, which is higher at slow shutter. Hot pixels stay still all the time, while noise is randomly flickering.

Other problems you might want to test are excessive audio noise from tape transport and red color bleeding.
To test the later you need to shot a bright red object on black background. You can place other colors in the frame to see if red is any different.
Also, I keep to hear about random mechanical problems with GL2, like autofocus stops working, zoom control fails, etc.

Have a lucky testing!

Michael Murray
June 5th, 2003, 02:46 PM
Thank you very much Vladimir. That's a great help.

About the "red smear" problem. From what I see it seems to be a common problem. I watched a BBC program last week -- "Changing Rooms" -- one of the girls was wearing a bright fuschia (red) outfit. It bled out all over the place. I was a bit shocked because the BBC has (or used to have) a reputation for quality.

I have the episode on tape, so, if anyone complains about my red smear I'll show them that mine is as good as the BBC.

Thank you again Vladimir, I'll follow your suggestions

Matthew Flesher
June 5th, 2003, 03:35 PM
Yes, thank you for the info Vladimir. I too just recieved my new GL-2 (very excited) and these tests are great to know. I have been trolling this board for the last couple months preparing for my purchase and look forward to becoming an active participant.

Chief

Vladimir Koifman
June 5th, 2003, 04:01 PM
Regarding the bleeding red artifact in GL2, there was an interesting post in rec.video usegroup:
http://groups.google.com/groups?dq=&hl=en&lr=&ie=UTF-8&oe=UTF-8&threadm=bb2unk%2497k%2401%241%40news.t-online.com&prev=/groups%3Fdq%3D%26num%3D25%26hl%3Den%26lr%3D%26ie%3DUTF-8%26oe%3DUTF-8%26group%3Drec.video%26start%3D75

Even though the poster is happy to say the problem is in Vegas codec, I'm not completely convinced. But the fact is no bleeding is seen on TV monitor.

You can check it by yourself.

Tustin Larson
June 5th, 2003, 06:42 PM
Thank you everyone for these wonderful tips. Our members input is very valuable to us. Thank you, and keep up the great work.

Thanx,

Steve Nunez
June 5th, 2003, 07:04 PM
I myself also noticed the red bleeding- but only on the GL2 LCD, not on the TV screen or imported footage to computer- so it's probably a shortcoming of the LCD more than a camera fault......here's a 23MB video of my airbrushed artwork featuring some "hot" girl models that displayed the "red bleeding" I saw on the LCD- notice the video doesn't exhibit the smearing.....

here's the video (hope you have broadband)

http://stevenunez.com/video/clips/snairbrushing.mov

Let me know what you guys think of the artwork.

Eric Gutknecht
June 5th, 2003, 07:41 PM
Very nice work Steve... You have an amazing talent with an airbrush my friend!

Cheers;
Eric

P.S Only comment about the video is that some of the transitions between images went by a bit too quick and I didn't get a chance to appreciate some of the stuff...

Matthew Flesher
June 5th, 2003, 09:07 PM
Nice stuff Steve! That Hulk bike is SWEET!

Chief

Marc Martin
June 6th, 2003, 07:25 PM
Regarding the bleeding red artifact in GL2, there was an interesting post in rec.video usegroup:
http://groups.google.com/groups?dq=...eo%26start%3D75

Even though the poster is happy to say the problem is in Vegas codec, I'm not completely convinced. But the fact is no bleeding is seen on TV monitor.

I'm not sure that it is a Vegas Codec problem. In Vegas, there is an option to use the Microsoft Codec, and this one has the same problem in the red.

I don't know how to try others decoders codecs, but if someone know how, I would be interested for testing others codecs like Canopus, Panasonic and more.

Steve Nunez
June 7th, 2003, 07:22 AM
Thanks guys....I'm an airbrush artist by trade and do this stuff all day- everyday....so it get's tiring real easy- the best part is when people see the work and tell you it's nice- so many thanks guys!

As for the red smearing- it's only an anomoly of the LCd and doesn't transfer over to the recorded video- so anyone seeing the "red" smearing shouldn't be too worried- if it showed up in the actual video- then I'd be worried.

For the most part- have fun guys- you only live once!

Jason Balich
June 7th, 2003, 12:35 PM
Do u think that the capture with premeire would be the same as vegas video with a firewire? Im just concerned and want to be do something about it if this is true. Any tests been doen with that software Vs Vegas Capture? Dont they both use the same microsoft codec to capture?

Alex Knappenberger
June 7th, 2003, 12:47 PM
Nope. Vegas uses Sonic Foundry's own DV codec, which has been proven to be MUCH better then Microsofts.

http://images.digitalmedianet.com/2001/12_dec/reviews/cw_vegasvid3/codec.jpg

http://www.digitalvideoediting.com/2001/12_dec/reviews/cw_vegasvid3.htm#