Serious flicker problem

Marty Hudzik · December 28th, 2006, 02:25 PM

OK. One thing to keep in mind. The Sony TV is probably a 720P set. I could be wrong. So the resolution of the TV would normally be 1280x720. Your computer monitor is probably just as hi res.....maybe....maybe not. Both Canons are known to be higher res than the sony. It is possible that you are just feeding a signal that is higher res than the TV can really handle. Maybe.

Again....until I can see the exact problem it is hard for me to say. I have a 45" 1920x1080 display that looks great for the H1. I also have a 26" Tv that is 1280x720 that sometimes shows jagged edges and just doesn't do the H1 justice.

The good news is that if both the HV10 and the H1 are showing this there is probably not a defect in your camera. I'd lean towards the higher res of the Canons to be the culprit.....but we need more testing. Do the canons seems uber sharp in comparison?

Good Luck!

Bruce S. Yarock · December 28th, 2006, 06:08 PM

Marty,
The Sony tv is a KD-30XS955 FD Trinitron Vega.I think it's 1080i and 720p.Under "specifications" it says-
"Inputs/outputs
HDMI in-Video-1080i,720p,480p,480i"

Then it says "component Video input" 2(Y,Pb,Pr). I use the Canon cable via component in.
The canons are no way sharper thn the Fx1, at least to my eye.
Just as a test, I used the Sony and the H1 to also view the same footage through the Same tv.Here were the results:
Sony FX1-No flicker on the front lawn(that was encouraging), minimal on the side of house.(That was a little better than through the HV10, but still not right). Flicker at the bird sanctuary(Not encouraging).
Canon H1-pretty much the same.
At this point, I need to get with someone local with a pro HD monitor and play the footage back through all 3 cameras. Also,I was thinking of dubbing the obviously 'flickering" sections to another tape and sending it to you to see waht you think.
Bruce S. Yarock

A. J. deLange · December 29th, 2006, 06:59 AM

The "flickering" is a combination of noise and aliasing. Noise can be reduced by decreasing the gain and shooting in even light (i.e. it's more visible in shadow where signal to noise ratio is worst). The aliasing is inherent in the design of any digital image sensor as has been discussed in this forum many times. Gain setting will have no effect on aliasing. There is, with HD, however, another place where aliasing can creep in and that is, as some have hinted here, with the display. The true 1920 x 1080 large screen TVs are just starting to enter the market now. Most of the old ones have appreciably lower resolutions and if the downconversion is not done right additional aliasing appears.

The XL-H1 seems to do a pretty good job of handling aliasing as opposed to the earlier XL series cameras. They may even have incorporated an optical antialiasing filter. This would cost some resolution but yield a reduction in the amount of aliasing recorded. So be sure to look at the video on a monitor that has 1920 x 1080 pixels i.e. one that does not require downsampling of the signal. All the aliasing will not be gone but it shouldn't be as noticeable as on some of the older large screen TV's which don't do the downsampling well.

Also watch some HD TV. You will see plenty of this flickering if you look for it. I was just watching some sportscaster the other night who must have bought his jacked from Moire Fashions. I was surprised that the producers let him wear it (though my set isn't 1920 in the H direction it does a pretty good job of downrezzing but that might have caused it).

A. J. deLange · December 29th, 2006, 07:00 AM

Duplicate post deleted

Bruce S. Yarock · December 29th, 2006, 07:39 AM

A.J.
What about a decent HD monitor? I was thinking of going to a local rental place and watching the clips through a real hd monitor.What should I ask them...if they have one that's 1920x 1080?
Thanks
Bruce S. yarock
www.yarock.com

Dan Keaton · December 29th, 2006, 04:01 PM

Dear Bruce,

I have researched your very nice Sony HD CRT television.

Sony does not specify what the native resolution is for your television, as is typical for most CRT based HDTV's.

While yours is a very nice set, I do not believe that it is "Full HD", ie 1920 x 1080. I say this to indicate that the flicker problem may actually be in your set and not your camera.

A test with a 1080p set, other than any CRT may determine if there is flicker in you footage. I do not know of any 1080p CRT's, at least in the normal price range.

Nick Hiltgen · December 29th, 2006, 04:30 PM

Take your camera to best buy and hop on one of the 1080p lcd displays. tell them your thinking about buying a new one or somehting but you want to see how ti looks. They won't care, heck they'd probably be happy to see something new on one of those screens. if you still have the issue report back.

Bruce S. Yarock · December 29th, 2006, 08:00 PM

Nick,
Good idea. I'll try tommorrow.
Bruce Yarock
www.yarock.com

A. J. deLange · December 30th, 2006, 07:05 AM

Yes, an HD monitor should do if it has 1920 x 1080 resolution or good downconversion circuitry (which a good monitor should). An LCD or plasma TV or projector should do as well. It was 6 months ago when I looked but at that time Westinghouse had just put a TV on the market with 1920 x 1080. There are doubtless others out there by now. Note that the set doesn't have to be capable of 1080p as the camera will put out 1080i even if you have shot in F mode (the fields will be aligned though so you will see 1080F).

Bruce S. Yarock · December 30th, 2006, 07:30 AM

A.J.
I shot the footage in 60i. I'm going to try Best Buy tommorrow and se if they have a set I can view through.If not,I know someone who has an HD monitor (don't know the specs) which I can try Tuesday.
thanks
Bruce S. yarock
www.yarock.com

Marty Hudzik · December 30th, 2006, 12:31 PM

Another thought about the sharpness between the H1 and FX1. If you have only ever viewed the footage on a TV that is capable of 720P then you have essentially limited the viewable resolution of both cameras. Even a TV that accepts 1080i might only be a 720 display and it performs a downconversion. My HD monitor that is hooked up to my PC is a CRT and it accepts 1080i and 720P but the actual resolution is only 1280x720. On this TV the HVX and the H1 look similar in resolution...with a minor edge going to the H1. However on my main TV which is a 45" 1920x1080 display, the H1 looks much better.

What I am getting at is that the FX1 may look every bit as sharp as the H1 on a 1280ish display but in reality both are being held back. The H1 may have more res and that could cause issues with the downsampling of the television in question, wherer the FX1 doesn't.

Regardless I think you can breathe a sigh of relief that your camera is probably not defective. If both the HV10 and the H1 show this issue it is probably a design thing and you just need to figure it out so you can work around it.

The HV10 actually has a 1920x1080 cmos sensor so it might exhibit this issue more....have you noticed a difference between the H1 and hte HV10?

Bruce S. Yarock · January 1st, 2007, 07:39 PM

"sigh of relief".
I played the footage through my parents new 46''Sony Brava, which is higher resolution than my Sony Vega HDTV, but not 1920x1080. I saw No...that's No flickering at all. So I guess the problem lies in my Sony Vega hdtv. Better there than in my H1.
Thanks, everybody.
Bruce Yarock
www.yarock.com

December 29th, 2006, 07:00 AM	#19
A. J. deLange Major Player Join Date: Jun 2004 Location: McLean, VA United States Posts: 749	Duplicate post deleted Last edited by A. J. deLange; December 29th, 2006 at 07:02 AM. Reason: Duplicate post deleted

December 29th, 2006, 04:01 PM	#21
Dan Keaton Inner Circle Join Date: Dec 2002 Location: Augusta Georgia Posts: 5,421	Dear Bruce, I have researched your very nice Sony HD CRT television. Sony does not specify what the native resolution is for your television, as is typical for most CRT based HDTV's. While yours is a very nice set, I do not believe that it is "Full HD", ie 1920 x 1080. I say this to indicate that the flicker problem may actually be in your set and not your camera. A test with a 1080p set, other than any CRT may determine if there is flicker in you footage. I do not know of any 1080p CRT's, at least in the normal price range. __________________ Dan Keaton Augusta Georgia

December 29th, 2006, 04:30 PM	#22
Nick Hiltgen Trustee Join Date: May 2003 Location: Atlanta GA Posts: 1,427	Take your camera to best buy and hop on one of the 1080p lcd displays. tell them your thinking about buying a new one or somehting but you want to see how ti looks. They won't care, heck they'd probably be happy to see something new on one of those screens. if you still have the issue report back. __________________ I have a dream that one day canon will release a 35mm ef to xl adapter and I'll have iris control and a 35mm dof of all my ef lenses, and it will be awesome...

December 28th, 2006, 02:25 PM	#16
Marty Hudzik Trustee Join Date: Jul 2004 Location: Canton, Ohio Posts: 1,771	OK. One thing to keep in mind. The Sony TV is probably a 720P set. I could be wrong. So the resolution of the TV would normally be 1280x720. Your computer monitor is probably just as hi res.....maybe....maybe not. Both Canons are known to be higher res than the sony. It is possible that you are just feeding a signal that is higher res than the TV can really handle. Maybe. Again....until I can see the exact problem it is hard for me to say. I have a 45" 1920x1080 display that looks great for the H1. I also have a 26" Tv that is 1280x720 that sometimes shows jagged edges and just doesn't do the H1 justice. The good news is that if both the HV10 and the H1 are showing this there is probably not a defect in your camera. I'd lean towards the higher res of the Canons to be the culprit.....but we need more testing. Do the canons seems uber sharp in comparison? Good Luck!

December 28th, 2006, 06:08 PM	#17
Bruce S. Yarock Trustee Join Date: May 2004 Location: Pembroke Pines, Fl. Posts: 1,842	Marty, The Sony tv is a KD-30XS955 FD Trinitron Vega.I think it's 1080i and 720p.Under "specifications" it says- "Inputs/outputs HDMI in-Video-1080i,720p,480p,480i" Then it says "component Video input" 2(Y,Pb,Pr). I use the Canon cable via component in. The canons are no way sharper thn the Fx1, at least to my eye. Just as a test, I used the Sony and the H1 to also view the same footage through the Same tv.Here were the results: Sony FX1-No flicker on the front lawn(that was encouraging), minimal on the side of house.(That was a little better than through the HV10, but still not right). Flicker at the bird sanctuary(Not encouraging). Canon H1-pretty much the same. At this point, I need to get with someone local with a pro HD monitor and play the footage back through all 3 cameras. Also,I was thinking of dubbing the obviously 'flickering" sections to another tape and sending it to you to see waht you think. Bruce S. Yarock

December 29th, 2006, 06:59 AM	#18
A. J. deLange Major Player Join Date: Jun 2004 Location: McLean, VA United States Posts: 749	The "flickering" is a combination of noise and aliasing. Noise can be reduced by decreasing the gain and shooting in even light (i.e. it's more visible in shadow where signal to noise ratio is worst). The aliasing is inherent in the design of any digital image sensor as has been discussed in this forum many times. Gain setting will have no effect on aliasing. There is, with HD, however, another place where aliasing can creep in and that is, as some have hinted here, with the display. The true 1920 x 1080 large screen TVs are just starting to enter the market now. Most of the old ones have appreciably lower resolutions and if the downconversion is not done right additional aliasing appears. The XL-H1 seems to do a pretty good job of handling aliasing as opposed to the earlier XL series cameras. They may even have incorporated an optical antialiasing filter. This would cost some resolution but yield a reduction in the amount of aliasing recorded. So be sure to look at the video on a monitor that has 1920 x 1080 pixels i.e. one that does not require downsampling of the signal. All the aliasing will not be gone but it shouldn't be as noticeable as on some of the older large screen TV's which don't do the downsampling well. Also watch some HD TV. You will see plenty of this flickering if you look for it. I was just watching some sportscaster the other night who must have bought his jacked from Moire Fashions. I was surprised that the producers let him wear it (though my set isn't 1920 in the H direction it does a pretty good job of downrezzing but that might have caused it).

December 29th, 2006, 07:39 AM	#20
Bruce S. Yarock Trustee Join Date: May 2004 Location: Pembroke Pines, Fl. Posts: 1,842	A.J. What about a decent HD monitor? I was thinking of going to a local rental place and watching the clips through a real hd monitor.What should I ask them...if they have one that's 1920x 1080? Thanks Bruce S. yarock www.yarock.com

December 29th, 2006, 08:00 PM	#23
Bruce S. Yarock Trustee Join Date: May 2004 Location: Pembroke Pines, Fl. Posts: 1,842	Nick, Good idea. I'll try tommorrow. Bruce Yarock www.yarock.com

December 30th, 2006, 07:05 AM	#24
A. J. deLange Major Player Join Date: Jun 2004 Location: McLean, VA United States Posts: 749	Yes, an HD monitor should do if it has 1920 x 1080 resolution or good downconversion circuitry (which a good monitor should). An LCD or plasma TV or projector should do as well. It was 6 months ago when I looked but at that time Westinghouse had just put a TV on the market with 1920 x 1080. There are doubtless others out there by now. Note that the set doesn't have to be capable of 1080p as the camera will put out 1080i even if you have shot in F mode (the fields will be aligned though so you will see 1080F).

December 30th, 2006, 07:30 AM	#25
Bruce S. Yarock Trustee Join Date: May 2004 Location: Pembroke Pines, Fl. Posts: 1,842	A.J. I shot the footage in 60i. I'm going to try Best Buy tommorrow and se if they have a set I can view through.If not,I know someone who has an HD monitor (don't know the specs) which I can try Tuesday. thanks Bruce S. yarock www.yarock.com

December 30th, 2006, 12:31 PM	#26
Marty Hudzik Trustee Join Date: Jul 2004 Location: Canton, Ohio Posts: 1,771	Another thought about the sharpness between the H1 and FX1. If you have only ever viewed the footage on a TV that is capable of 720P then you have essentially limited the viewable resolution of both cameras. Even a TV that accepts 1080i might only be a 720 display and it performs a downconversion. My HD monitor that is hooked up to my PC is a CRT and it accepts 1080i and 720P but the actual resolution is only 1280x720. On this TV the HVX and the H1 look similar in resolution...with a minor edge going to the H1. However on my main TV which is a 45" 1920x1080 display, the H1 looks much better. What I am getting at is that the FX1 may look every bit as sharp as the H1 on a 1280ish display but in reality both are being held back. The H1 may have more res and that could cause issues with the downsampling of the television in question, wherer the FX1 doesn't. Regardless I think you can breathe a sigh of relief that your camera is probably not defective. If both the HV10 and the H1 show this issue it is probably a design thing and you just need to figure it out so you can work around it. The HV10 actually has a 1920x1080 cmos sensor so it might exhibit this issue more....have you noticed a difference between the H1 and hte HV10?

January 1st, 2007, 07:39 PM	#27
Bruce S. Yarock Trustee Join Date: May 2004 Location: Pembroke Pines, Fl. Posts: 1,842	"sigh of relief". I played the footage through my parents new 46''Sony Brava, which is higher resolution than my Sony Vega HDTV, but not 1920x1080. I saw No...that's No flickering at all. So I guess the problem lies in my Sony Vega hdtv. Better there than in my H1. Thanks, everybody. Bruce Yarock www.yarock.com