View Full Version : XL2 5.5 lux and no A/V dub?


R.C. White
July 21st, 2004, 07:42 PM
Thanks to everyone for all the good questions and answers I have already read. I hope I didn't miss what I am about to ask.

Unlike most of you, I use my XL1s for freelance news gathering, so I don't presently care about 16:9. But I do care about the camera's ability to function well in low light and to be able to record a dub from another camera or deck.

The stated 5.5 lux rating is much less than the 2 lux that Canon has on their on-line spec sheet for my XL1s. With different sensors, are we comparing apples to apples or apples to oranges? Now I read the 5.5 is really a 3. Says who? And forget about the 30db gain the XL1s has, it's worthless.... It all boils down to: Will the XL2 perform better or worse than the XL1s in low light.

As for recording a video feed, I read that amongst the differences between the XL1s and the XL2 is that the XL2 will not do A/V dubbing.....yet they say the BNC and XLR connections are input/output. I'm confused....will the owner of an XL2 be able to take a composite feed via cable from another source? I couldn't with the original XL1, then I could with my GL1 and the XL1s, but now what's the story with the XL2? (If you're wondering why, courtroom work often involves working in a camera pool...sometimes you are the camera and feed to others and sometimes you just use your camera as a deck and get the feed from the guy stuck standing at his sticks all day....)

This last question may be stupid, but I'll ask it anyway. If someone were to shoot in 4:3 a couple of hours a day for a couple of years, and then switched to shoot something in 16:9, do you think you'd be able to tell which pixels had been "off" for 2 years and which had been on?

Please keep the questions and answers coming.

Thanks,

Bob

Chris Hurd
July 21st, 2004, 08:44 PM
Bob

A/V dubbing refers to a playback operation in VCR mode. Dubbing audio over existing video or vice-versa.

Lux ratings, it's 5.5 at 1/60th sec in program AE mode with 0db gain. You can always switch to the program Low-Light mode, or slow down the shutter speed, or add gain. The gain is fairly clean even at +12db, and not too majorly noisy at +18db.

Hope this helps,

R.C. White
July 21st, 2004, 08:55 PM
Chris, thanks for clarifying the A/V dub. One down, one to go!

Regarding the low light ability, I understand I can go to manual, up the gain, slow the shutter (but if i read the spec correctly apparently not as slow on the XL2 as on the XL1s.... and if that's true, it's a shame, as I used the REALLY slow shutter of the XL1s to create some drunken effects for a MADD video...) But, what I am trying to establish is a baseline. Will the XL2 offer low light sensitivity better than, equal to or worse than the existing XL1s???

Anyone have a clue?

Thanks again for all the hard work.

Bob

Paul Colt
July 22nd, 2004, 05:00 AM
Hey Bob if you read the post I put up from camcorderinfo.com it shows the DVX and the XL-2 with the same lux rating at 3 lux. That also is comfirmed from the Canon web sites I've visited. I think its a non issue now anyway.

Jeff Donald
July 22nd, 2004, 06:07 AM
Lux measurements are always a non-issue. There are no standards for the measurement of lux. Manufactures don't even uniformly apply the ratings among their own models. Many times they assume that consumers will except a lower quality image than a professional and use different methods and standards for one model versus another model. None of the manufactures disclose the methods and standards used, so the only effective manner is to subjectively compare the images generated by the cameras in the same lighting conditions. Your comparisons can be made more reliable if the images are compared with a waveform monitor and vectorscope.

Jacques Mersereau
July 22nd, 2004, 07:24 AM
I agree with Mr. Donald.

At NAB this year, the B&H booth had a DVX100a setup next to the PD-170.
Although the spec on PD is 1 lux and the DVX is 3, we decided to see what
the real deal was. According to the specs, the PD should rule the DVX.

I asked the booth guy to turn off the light that shone on a bowl of fruit.
We framed both cameras on it. Hmmmm. The images on their respective
monitors where very similar. The DVX did NOT show a darker image
by anyone's eye ball. Nor was the DVX image noisy.

We then tilted both cameras up high towards the steel rafters.
(And this is good) The contrast handling of the DVX
smoked the PD. After a couple of rafters the PD's image went black,
while the DVX, with its 12 bit processing, could "see" _much_ further into the shadows.
In fact the DVX image never went totally black. WOW!

Specs don't matter to me . . . reality matters and I would love it if someone
could put the new XL2 next to a PD or DVX and compare the cameras
that way. If the XL2 can equal the PD or DVX then I think it is a SOLID choice.

Don Palomaki
July 22nd, 2004, 04:37 PM
There is a Consumer Electronics Association (CEA) standard for lux rating, but it is optional and as noted by others, most camcorder makers do not follow it in their literature. It has been around in some form (under EIA) since at least the early 1990s.

You can buy a copy for about $47 from Global Engineering Documents. The citation:

CEA SP 2056, Revision: 01 Chg: Date: 09/12/03
CONSUMER CAMCORDER OR VIDEO CAMERA LOW LIGHT PERFORMANCE

Issues with low light performance include: aperture, shuttter, gain, noise level, and the IRE produce by what brightness (or reflectivity) object.

One way to specify it might be the lux required incident on a standard 18% gray card to produce 20 IRE with a 30 dB video signal to noise at 1/60 shutter, max aperture, and using whatever gain seeting that stays within the S/N? But that is not likely the form of the actual CEA spec.

Jeff Donald
July 22nd, 2004, 05:09 PM
I think the original spec applied only to VHS. They tried to adopt it to DV, but the manufactures wouldn't voluntarily participate.