My picture looks like this... at DVinfo.net

Jesse Dean · November 26th, 2007, 11:45 AM

I'm getting this picture when I shoot with the XH - A1. This isn't my camera and it's the first time I've used this Canon model. I did change the gain down to -3 but I still get a lot of noise or fuzz. Again, I'm not the smartest technical cat when it comes to this camera so please explain as clear as possible.

http://i11.tinypic.com/7xim07r.png

http://i16.tinypic.com/6l14ba8.png

Chris Hurd · November 26th, 2007, 12:02 PM

Be sure to slide the AGC switch to the "off" position.

Bill Pryor · November 26th, 2007, 01:03 PM

Yep, it looks like that was shot at the highest gain possible.

Jesse Dean · November 26th, 2007, 02:10 PM

Quote:

Originally Posted by Chris Hurd

Be sure to slide the AGC switch to the "off" position.

That helped a lot. Thanks. I'll have to wait and see what it looks like thou when I shoot.

What does AGC stand for and why would one use it?

Chris Barcellos · November 26th, 2007, 02:14 PM

Automatic Gain Control. It adjust to exposure to "acceptable" levels after you have modified other inputs. Unless you turn it off, you will have a lot of gain and attendant grain in your shot.

What is curious here is that the shots seem to be in a lit situation to some extent, so I am wondering if you had your neutral density filters engaged too, forcing camera with AGC on to add gain to get exposure up.

Dirk Bouwen · November 26th, 2007, 02:31 PM

After one year of XH A1, I'm still not feeling confident about HDV's in low light situations.

Coming from VX/PD, this is a challenge, most of all because in field with ,o more help than the EVF and LCD panel, even with peaking and magnify, you might end up back home with footage like this. In other words, your eyes may mislead you very easy, may be the biggest disappointment once captured on your computer. And I don't want to hook-up a 12" monitor on my camera for the purposes I use it.

Like every A1-user I've gone through quite a lot of experimenting with presets, negative gains, but with grays and dark blues it's almost impossible in low light to come close to any quality result without additional lighting. NR1 and 2, coring, ... no preset, no setting whatsoever will completely get you out of throuble. I surely don't accept filming with shutter below 1/50 or with a gain ramped up to +12dB, for most purposes this is just impossible.

To correct excessive noise as shown on the two pictures in post, is a no go, ofcourse. Most of all these artifacts are blown up to an almost unacceptable defeat of quality on plasma's and LCD's, thus...

Another booby-trap is the AGC switch.

Instead of seeing some weird icon on your display when it's switched on, you notice... nothing (!), only the gain indication has disappeared. What an inconvenience, Canon!

It happened to me by accident (no clue it was on though I knew what disaster it could cause), on a bright summer day, and I had quite some footage spoiled... Sure, it's stupid. I should have noticed something with the shutter/aperture was wrong, but still...? Put a tape over it. Glue it to fix it. This insane button has no use at all.

In general, noise in low light seems to be 'common' in this range of camera's, still - even if the A1 is just like its collegues a brilliant camera in nearly all daylight conditions - everything gets quite different when it gets dark... (and again, this is surely no VX/PD !!!)

Recent, I tried the HV20, and the behaviour is quite similar, but even more emphasized in the low light area.

In other words, if this is your budget, live with it, buy a video light - which isn't always the most obvious tool to use.

Jesse Dean · November 26th, 2007, 07:39 PM

Thanks Chris, it seems that this camera wouldn't be for me than.

Luckily this camera isn't mine, but I will be buying one soon. If you could only buy a camera for under $5k-$6K (after taxes) what would it be.

I use my camera for low light conditions.

I have a strong 35watt Frezzi Mini Light already.

I will shoot in clubs, bars, interviews and random events.

Most of the content is for websites, so HD isn't necessary but would be nice to have since I want to use this camera for the next 4-5 years.

True Widescreen 16:9, True 30P and True 1080i would be nice.

Any other suggestions to what I should look out for or mistakes you guys made after you bought your camera that I should know about.

Jack Walker · November 26th, 2007, 09:44 PM

For low-light and web video, I think the PD-170 is the camera.

The new EX might be the new HD "handicam" low-light answer, with the larger chips.

I also have a JVC HD110, but I think the XH-A1 is unbeatable for many situations.

A piece of gaffer tape over a couple of the slide switches helps in general many times.

I don't like about 3 of the switches on the XH-A1 because they are either hard to find without looking and/or can't be locked on or off.

I would also like a colored ring on the focus, iris and zoom rings, perhaps studded with the letter f, i and z and with arrow indicators that instantly identify open/close, in/out, farther/nearer. (Of course a person with decent short term and/or long term memory doesn't have as great a need for this.).

For HDV on a steadicam easy for travel, I don't think the XH-A1 can be beat. For my use, the XH-A1 has fantastic autofocus... much better, I believe, than the Sony PD150 I have.

Bill Pryor · November 27th, 2007, 10:36 AM

Everybody says that because of the higher resolution chips (ie., more pixels in the same space) the HDV cameras don't have as good low light capability as older SD cameras such as the PD150/170. I did a side-by-side comparison with a DSR250 (same chips as the 150) and found only about half a stop difference, if that much.

Also, by shooting at 24f and a 1/48 shutter, you get more light than at 60i and 1/60 shutter. I also found that I could go up to about a +3db and still look better than the SD camera at zero. In comparisons with a Sony Z1 I found that the XH A1 was just a little better at very low light, but later I realized I was shooting at 24f and with the Z1 at 60i (it doesn't have a progressive mode that's good); so in retrospect both cameras under equal settings are probably the same. I think the Z1 holds up a little better under higher gain than the XH A1, but the differences are really very minor.

When shooting under low light you want to make sure all the auto stuff is turned off, ie., auto iris, auto gain, auto shutter. Any one of those three left on is going to cause you trouble. Get it all off, make sure your ND filter is at zero, make sure your gain is a zero and see what you get at a fairly wide angle. Under seriously low light conditions, you can't zoom in very far because the lens, like all the electronic lenses, will stop itself down. So you have to stay pretty wide.

Steve Yager · November 27th, 2007, 05:06 PM

If you have a good on-camera light then I wouldn't worry about the A1's low light problems. If you buy an SD cam at this point over the A1 you're paying too much.

November 26th, 2007, 11:45 AM	#1
Jesse Dean New Boot Join Date: Nov 2007 Location: San Francisco, California Posts: 4	My picture looks like this... I'm getting this picture when I shoot with the XH - A1. This isn't my camera and it's the first time I've used this Canon model. I did change the gain down to -3 but I still get a lot of noise or fuzz. Again, I'm not the smartest technical cat when it comes to this camera so please explain as clear as possible. http://i11.tinypic.com/7xim07r.png http://i16.tinypic.com/6l14ba8.png Last edited by Jesse Dean; November 26th, 2007 at 11:45 AM. Reason: Can't post pictures in this forum?

November 26th, 2007, 12:02 PM	#2
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,366 Images: 513	Be sure to slide the AGC switch to the "off" position. __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

November 26th, 2007, 02:14 PM	#5
Chris Barcellos Inner Circle Join Date: Nov 2005 Location: Elk Grove CA Posts: 6,838	Automatic Gain Control. It adjust to exposure to "acceptable" levels after you have modified other inputs. Unless you turn it off, you will have a lot of gain and attendant grain in your shot. What is curious here is that the shots seem to be in a lit situation to some extent, so I am wondering if you had your neutral density filters engaged too, forcing camera with AGC on to add gain to get exposure up. __________________ Chris J. Barcellos

November 26th, 2007, 02:31 PM	#6
Dirk Bouwen Regular Crew Join Date: Nov 2006 Location: AC, Belgium Posts: 75	HDV and low light After one year of XH A1, I'm still not feeling confident about HDV's in low light situations. Coming from VX/PD, this is a challenge, most of all because in field with ,o more help than the EVF and LCD panel, even with peaking and magnify, you might end up back home with footage like this. In other words, your eyes may mislead you very easy, may be the biggest disappointment once captured on your computer. And I don't want to hook-up a 12" monitor on my camera for the purposes I use it. Like every A1-user I've gone through quite a lot of experimenting with presets, negative gains, but with grays and dark blues it's almost impossible in low light to come close to any quality result without additional lighting. NR1 and 2, coring, ... no preset, no setting whatsoever will completely get you out of throuble. I surely don't accept filming with shutter below 1/50 or with a gain ramped up to +12dB, for most purposes this is just impossible. To correct excessive noise as shown on the two pictures in post, is a no go, ofcourse. Most of all these artifacts are blown up to an almost unacceptable defeat of quality on plasma's and LCD's, thus... Another booby-trap is the AGC switch. Instead of seeing some weird icon on your display when it's switched on, you notice... nothing (!), only the gain indication has disappeared. What an inconvenience, Canon! It happened to me by accident (no clue it was on though I knew what disaster it could cause), on a bright summer day, and I had quite some footage spoiled... Sure, it's stupid. I should have noticed something with the shutter/aperture was wrong, but still...? Put a tape over it. Glue it to fix it. This insane button has no use at all. In general, noise in low light seems to be 'common' in this range of camera's, still - even if the A1 is just like its collegues a brilliant camera in nearly all daylight conditions - everything gets quite different when it gets dark... (and again, this is surely no VX/PD !!!) Recent, I tried the HV20, and the behaviour is quite similar, but even more emphasized in the low light area. In other words, if this is your budget, live with it, buy a video light - which isn't always the most obvious tool to use.

November 26th, 2007, 07:39 PM	#7
Jesse Dean New Boot Join Date: Nov 2007 Location: San Francisco, California Posts: 4	? Thanks Chris, it seems that this camera wouldn't be for me than. Luckily this camera isn't mine, but I will be buying one soon. If you could only buy a camera for under $5k-$6K (after taxes) what would it be. I use my camera for low light conditions. I have a strong 35watt Frezzi Mini Light already. I will shoot in clubs, bars, interviews and random events. Most of the content is for websites, so HD isn't necessary but would be nice to have since I want to use this camera for the next 4-5 years. True Widescreen 16:9, True 30P and True 1080i would be nice. Any other suggestions to what I should look out for or mistakes you guys made after you bought your camera that I should know about.

November 26th, 2007, 01:03 PM	#3
Bill Pryor Contributor Join Date: Jan 2003 Location: Kansas City, MO Posts: 4,449	Yep, it looks like that was shot at the highest gain possible.

November 26th, 2007, 09:44 PM	#8
Jack Walker Trustee Join Date: Jun 2006 Location: Burbank Posts: 1,811	For low-light and web video, I think the PD-170 is the camera. The new EX might be the new HD "handicam" low-light answer, with the larger chips. I also have a JVC HD110, but I think the XH-A1 is unbeatable for many situations. A piece of gaffer tape over a couple of the slide switches helps in general many times. I don't like about 3 of the switches on the XH-A1 because they are either hard to find without looking and/or can't be locked on or off. I would also like a colored ring on the focus, iris and zoom rings, perhaps studded with the letter f, i and z and with arrow indicators that instantly identify open/close, in/out, farther/nearer. (Of course a person with decent short term and/or long term memory doesn't have as great a need for this.). For HDV on a steadicam easy for travel, I don't think the XH-A1 can be beat. For my use, the XH-A1 has fantastic autofocus... much better, I believe, than the Sony PD150 I have.

November 27th, 2007, 10:36 AM	#9
Bill Pryor Contributor Join Date: Jan 2003 Location: Kansas City, MO Posts: 4,449	Everybody says that because of the higher resolution chips (ie., more pixels in the same space) the HDV cameras don't have as good low light capability as older SD cameras such as the PD150/170. I did a side-by-side comparison with a DSR250 (same chips as the 150) and found only about half a stop difference, if that much. Also, by shooting at 24f and a 1/48 shutter, you get more light than at 60i and 1/60 shutter. I also found that I could go up to about a +3db and still look better than the SD camera at zero. In comparisons with a Sony Z1 I found that the XH A1 was just a little better at very low light, but later I realized I was shooting at 24f and with the Z1 at 60i (it doesn't have a progressive mode that's good); so in retrospect both cameras under equal settings are probably the same. I think the Z1 holds up a little better under higher gain than the XH A1, but the differences are really very minor. When shooting under low light you want to make sure all the auto stuff is turned off, ie., auto iris, auto gain, auto shutter. Any one of those three left on is going to cause you trouble. Get it all off, make sure your ND filter is at zero, make sure your gain is a zero and see what you get at a fairly wide angle. Under seriously low light conditions, you can't zoom in very far because the lens, like all the electronic lenses, will stop itself down. So you have to stay pretty wide.

November 27th, 2007, 05:06 PM	#10
Steve Yager Regular Crew Join Date: Apr 2007 Location: Los Angeles Posts: 157	If you have a good on-camera light then I wouldn't worry about the A1's low light problems. If you buy an SD cam at this point over the A1 you're paying too much.