XM2 random greenish tint at DVinfo.net

Martin Lindstedt · May 3rd, 2006, 08:18 AM

I bought a brand new Xm2 a couple of months ago and I haven't had a problem with it until recently.

When using frame mode I've sometimes noticed a random, greenish tinge to the footage. It´s not static, it comes and goes and it´s pretty noticable. It seems to appear when camera has been running for a while.

Has anyone experienced anything like this?

I had the camera set to manual mode, INCLUDING white balance, so it can't be a WB related issue.

It seemed to go away when I switched to normal mode ( instead of frame mode ), but I have to recheck that to be 100% sure. ( Even though it would make sense .. perhaps some kind of a bug in the green-pixel-shift-faux-progressiv-thingy? )

I managed to record the tinge last night, so if necessay I can post a short clip of it.

Any help appriciated!

Graham Bernard · May 3rd, 2006, 12:20 PM

Hmmm . .not in Normal mode eh?

Have you a preset engaged when in Manual/Frame mode?

Grazie

Martin Lindstedt · May 3rd, 2006, 03:12 PM

Hey Grazie!

"Have you a preset engaged when in Manual/Frame mode?"

Yes, I have the custom preset turned on. I´ve just pulled the sharpness down alittle. You think it might be the problem?

Graham Bernard · May 3rd, 2006, 05:11 PM

Hiyah . . You got anything wandering towards the GREEN within that preset?

You are manually white balancing? If so against what? What "white" are you using? I know I can get some extraordinary effects using different coloured boards. Also I can get a nasty yellowy/green tinge with certain lighting too!! What environment gets you this green tinge? Outside and inside? Have you used the WB templates?

Grazie

Greg Boston · May 3rd, 2006, 05:21 PM

It can happen if you are shooting under flourescent lighting using certain shutter speeds. It's the difference in phasing between frequency of the light ballast verses shutter speed. If taping under FL lights, set your shutter speed to the power line frequency which would be 1/50th for PAL. This eliminates the slow phase drift. Although you see it as green tinge, it's likely a change in the light levels which will affect color saturation due to the aforementioned effect.

BTW, this is the reason why flourescent lighting units for video work have special high frequency ballasts so as to eliminate that shifting.

-gb-

Martin Lindstedt · May 4th, 2006, 03:41 AM

Grazie!

No, the preset is flat, except for sharpness. I used the indoor WB template. The problem is not the green tinge itself but the fact that the green spectrum in the camera seems to fluctuate.

I have put a short clip here:

http://martin.cmplete.com/greenblink.wmv

Do you guys see it? Sorry for the shaky footage.

Greg!

I actually have a fluorescent lamp next to me, and yes, it was on when I saw the effect.

I tried without it, but no, the problem remains.

Any ideas?

Graham Bernard · May 4th, 2006, 04:43 AM

My first thoughts were, get some light on the subject! As were my next thoughts.

For my money, the camera is truly struggling to do anything. I even had to put your clip into Vegas, bump the GAIN just to see exactly what I was looking at.

When you shot this, just what was your exposure scale reading?

I think what you are observing is very low lighting cast by the floro you say. I think Greg's comments are spot on. Plus, give your poor camera some lighting to play with? It is only a 1/4 CCD - give it a chance! If it isn't any of these then I really don't know what is happening.

G

Martin Lindstedt · May 4th, 2006, 05:19 AM

hehe, yeah, it was heavily underexposed and out of focus , i know. I was fooling around with the shutter speed, to see if it had any impact on it. Sorry bout that ..

Have a look at this clip.

http://martin.cmplete.com/greenblink2.avi

In this scene I am shooting only in sunlight thru the window. Watch the hand and the shirt a couple of times. It´s subtle, but the green blink is there.

You're gonna have to tell me if I am being too picky about this, I just feel that a camera of this caliber shouldn´t be doing this. If it turns out that this is a normal behaviour for all XM2 out there, it would be a big relief for me, knowing that I don´t have a faulty camera.

It seems like it´s easier to replicate the problem with my larger nobrand battery. So I measured the voltage on it.

8,4 V.

That´s too much, the camera only needs 7,4. The orginal Canon battery was dead on.

So it could be my battery feeding too much voltage to the camera making it go crazy after a while. What do you guys think ?

Greg Boston · May 4th, 2006, 06:49 AM

Quote:

Originally Posted by Martin Lindstedt

It seems like it´s easier to replicate the problem with my larger nobrand battery. So I measured the voltage on it.

8,4 V.

That´s too much, the camera only needs 7,4. The orginal Canon battery was dead on.

So it could be my battery feeding too much voltage to the camera making it go crazy after a while. What do you guys think ?

That could be a problem. It's not worth damaging your camera over a nobrand battery. The Canon actually runs on 7.2 volts so I would not use that battery. Try running the camera off of AC mains and see what happens. That should give you a stable unchanging reference to evaluate the issue with.

-gb-

May 3rd, 2006, 08:18 AM	#1
Martin Lindstedt Regular Crew Join Date: Jul 2004 Location: Malmö, Sweden Posts: 25	XM2 random greenish tint I bought a brand new Xm2 a couple of months ago and I haven't had a problem with it until recently. When using frame mode I've sometimes noticed a random, greenish tinge to the footage. It´s not static, it comes and goes and it´s pretty noticable. It seems to appear when camera has been running for a while. Has anyone experienced anything like this? I had the camera set to manual mode, INCLUDING white balance, so it can't be a WB related issue. It seemed to go away when I switched to normal mode ( instead of frame mode ), but I have to recheck that to be 100% sure. ( Even though it would make sense .. perhaps some kind of a bug in the green-pixel-shift-faux-progressiv-thingy? ) I managed to record the tinge last night, so if necessay I can post a short clip of it. Any help appriciated!

May 3rd, 2006, 12:20 PM	#2
Graham Bernard Old Boot Join Date: Aug 2002 Location: London UK Posts: 3,633	Hmmm . .not in Normal mode eh? Have you a preset engaged when in Manual/Frame mode? Grazie

May 3rd, 2006, 03:12 PM	#3
Martin Lindstedt Regular Crew Join Date: Jul 2004 Location: Malmö, Sweden Posts: 25	Hey Grazie! "Have you a preset engaged when in Manual/Frame mode?" Yes, I have the custom preset turned on. I´ve just pulled the sharpness down alittle. You think it might be the problem?

May 3rd, 2006, 05:11 PM	#4
Graham Bernard Old Boot Join Date: Aug 2002 Location: London UK Posts: 3,633	Hiyah . . You got anything wandering towards the GREEN within that preset? You are manually white balancing? If so against what? What "white" are you using? I know I can get some extraordinary effects using different coloured boards. Also I can get a nasty yellowy/green tinge with certain lighting too!! What environment gets you this green tinge? Outside and inside? Have you used the WB templates? Grazie

May 3rd, 2006, 05:21 PM	#5
Greg Boston Wrangler Join Date: Oct 2003 Location: DFW area, TX Posts: 6,117 Images: 1	It can happen if you are shooting under flourescent lighting using certain shutter speeds. It's the difference in phasing between frequency of the light ballast verses shutter speed. If taping under FL lights, set your shutter speed to the power line frequency which would be 1/50th for PAL. This eliminates the slow phase drift. Although you see it as green tinge, it's likely a change in the light levels which will affect color saturation due to the aforementioned effect. BTW, this is the reason why flourescent lighting units for video work have special high frequency ballasts so as to eliminate that shifting. -gb-

May 4th, 2006, 03:41 AM	#6
Martin Lindstedt Regular Crew Join Date: Jul 2004 Location: Malmö, Sweden Posts: 25	Grazie! No, the preset is flat, except for sharpness. I used the indoor WB template. The problem is not the green tinge itself but the fact that the green spectrum in the camera seems to fluctuate. I have put a short clip here: http://martin.cmplete.com/greenblink.wmv Do you guys see it? Sorry for the shaky footage. Greg! I actually have a fluorescent lamp next to me, and yes, it was on when I saw the effect. I tried without it, but no, the problem remains. Any ideas?

May 4th, 2006, 04:43 AM	#7
Graham Bernard Old Boot Join Date: Aug 2002 Location: London UK Posts: 3,633	My first thoughts were, get some light on the subject! As were my next thoughts. For my money, the camera is truly struggling to do anything. I even had to put your clip into Vegas, bump the GAIN just to see exactly what I was looking at. When you shot this, just what was your exposure scale reading? I think what you are observing is very low lighting cast by the floro you say. I think Greg's comments are spot on. Plus, give your poor camera some lighting to play with? It is only a 1/4 CCD - give it a chance! If it isn't any of these then I really don't know what is happening. G

May 4th, 2006, 05:19 AM	#8
Martin Lindstedt Regular Crew Join Date: Jul 2004 Location: Malmö, Sweden Posts: 25	hehe, yeah, it was heavily underexposed and out of focus , i know. I was fooling around with the shutter speed, to see if it had any impact on it. Sorry bout that .. Have a look at this clip. http://martin.cmplete.com/greenblink2.avi In this scene I am shooting only in sunlight thru the window. Watch the hand and the shirt a couple of times. It´s subtle, but the green blink is there. You're gonna have to tell me if I am being too picky about this, I just feel that a camera of this caliber shouldn´t be doing this. If it turns out that this is a normal behaviour for all XM2 out there, it would be a big relief for me, knowing that I don´t have a faulty camera. It seems like it´s easier to replicate the problem with my larger nobrand battery. So I measured the voltage on it. 8,4 V. That´s too much, the camera only needs 7,4. The orginal Canon battery was dead on. So it could be my battery feeding too much voltage to the camera making it go crazy after a while. What do you guys think ?