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-   Canon XL1S / XL1 Watchdog (https://www.dvinfo.net/forum/canon-xl1s-xl1-watchdog/)
-   -   Night time settings for xl1s (https://www.dvinfo.net/forum/canon-xl1s-xl1-watchdog/45328-night-time-settings-xl1s.html)

Rob Brookes May 28th, 2005 07:03 AM

Night time settings for xl1s
 
Heh guys.
Just want to check that I am shooting with good settings for night.
Manual mode, 1.6fs, shutter 1/25, gain +6,+12db and manual focus.
I do have a little sungun light and when I have people in front of camera with light on I bring gain to 0 and exposure down a little so subject is not over exposed, and I dont touch the shutter. Does this sound familiar to you all.

Rob Lohman May 29th, 2005 03:55 AM

Are you shooting in frame mode? If so you may want to shoot in interlaced,
that mode requires less light. Otherwise it sounds like your settings are the
best with what you can get away with. Adding light usually is the best way!

Rob Brookes May 30th, 2005 03:03 PM

Hi Rob, yes I do shoot interlaced (normal) as frame mode is a little stuttery with movement etc. I was surprised to hear that frame mode uses more light, thats good to know. Have you used a canon xl1s much Rob and do you have any solution to the light flare problem with the standard canon lense. Eg, sun shining off cars and flood lights at night flaring really badly. Thanks again

Rob Lohman June 1st, 2005 04:44 AM

Yes, I have used the XL1S (PAl model) for 3 years. I've never really had much
problems with flairs. I did however use a circular polarizer on some occasions.

Rob Brookes June 1st, 2005 02:59 PM

What did the circular polariser do for you and when was it good to use. I am a little surprised you did not experience the flare problem. It happens anytime a night light is in frame,eg, car head lights, sports stadium lights, and at daytime it even flares up over a sun reflection off a car window. I use the ND filter built in the lens at day when theres plenty of light. Maybe I should use a polarizer, uv filter or something to cut this down. Rob, even if I was shooting a candle the light flares, no matter what manual settings I do.
Maybe I should email you a few frame grabs, I would love to get to the bottom of this

Rob Lohman June 2nd, 2005 03:50 AM

Sure, send me some grabs to visuar@gmail.com

I'll put them up for everyone to see.

Me not seeing the flares does not mean my camera didn't have that "problem".
It just means I never saw it with my camera. I didn't do much night recording
at all or shoot bright lights (that I can remember).

A circular polarizer can be rotated to let polarized light from a certain angle
go through and block all others. This can be very helpful with effects like
light bouncing of water, or other reflective services like glass and metal. It
helps decide how reflective or transparent the material looks on camera.

With a car windshield on a car you can go from reflective (seeing trees
reflect in the shield for example) to seeing the passengers inside the car.

I'm not sure if it will do much good with flares (there may be anti-flaring
filters as well, take a look at the tiffen filter catalog), but it's always nice
to have a polarizer available when you need it.

Rob Brookes June 2nd, 2005 02:39 PM

Thanks Rob. I will get the frame grabs and send them to you soon. I will look into the filters, tiffen have been mentioned a bit actually. Speak soon

Rob Lohman June 12th, 2005 07:43 AM

Okay, I've put the framegrabs up:

http://www.visuar.com/DVi/Brookes1.jpg
http://www.visuar.com/DVi/Brookes2.jpg
http://www.visuar.com/DVi/Brookes3.jpg
http://www.visuar.com/DVi/Brookes4.jpg

As I said in my e-mail, this doesn't look good to me at all. However, I'm not
sure what could be causing this. I will try to get some more knowledgable
folk to this thread.

Jack Smith June 12th, 2005 11:46 AM

Try a test. Shoot some stuff as in the framegrabs then turn the camera (rotate) 45 deg so that the horizon is on 45 deg angle.Then pan. Do then the flares change to the 45 deg angle?
Test 2 while shooting truck the camera. Do the flares change?
When the light source is aimed directly at the lense you will get flare.Especially if your aperature is wide open.Try adding gain and stopping down.Also truck the camera so as not to be in the direct aim of the light source.These framegrabs appear to be very high contrast lighting ( no fill)
and difficult to loose the flares.But if the camera is moving that may not be a bad thing.I kinda like the look of flares coming in and out for certain shots.

Pete Bauer June 12th, 2005 01:57 PM

I presume the issue is what I'll unofficially call "vertical banding" that eminates from the bright lights? If so, I suspect there's nothing wrong with the camera, but shooting for extreme low light with those high wattage, high-intensity floods in-frame is just simply going to do that.

Here's an XL2 thread that sounds similar:
http://www.dvinfo.net/conf/showthrea...light=artifact

I can't be sure how susceptible the XL1s is to this kind of artifact since I don't use that camera, but all video cameras ARE subject to it to some extent. Really just gotta keep such extreme light sources as those lights out of frame, I think.

EDIT: If you're already down to 1/25th shutter speed, open aperture, and gained up, I guess I don't see ND or Polarizer filters as being much help. You're already getting a lot of blur from the slow shutter. If possible, shoot from a higher vantage point so the lights stay out of frame.

Rob Brookes June 12th, 2005 04:45 PM

True, True. Thanks for everyones input, Rob for putting grabs on his site. I have ordered some tiffen filters, circular polarizer and a uv filter for protection. Like you said, I will endeavour to keep the light source out of shot and try to stop down a little, minimising flare. I guess if you have a really fast lense the flaring would be minimised aswell because you could stop down more, wouldnt you say.Why do exspensive broadcast cameras handle light so well, is it because the ccds are bigger or the lens itself?

Patrick King June 12th, 2005 05:41 PM

Rob,

The phenomenom displayed in your screen grabs appears to be 'vertical smear' as described here.

This is actually a CCD issue and not a lens issue. Flare is a lens issue, but your screen grabs don't demonstrate what I've seen described as flare.

Rob Brookes June 13th, 2005 03:34 AM

Patrick,

Read your thread and it was very interesting. I suppose then that you can not do much if the ccds react that way to intense light. I am getting a polarizer and uv filter however I am starting to think its now not the lens but the ccds that are causing the smear as it seems to be now.

From what I hear, the more exspensive HADS and other brand chips found in broadcast cameras eliminate (or greatly reduce) smear.


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