Which cameras have IR issues?

A

asafb

Active member
Hello,
Does anyone know which cameras have IR issues and which ones do not - I know the following do:

Sony EX1
Sony EX3
Panasonic HVX200
Red One
Panasonic Varicam (Tape-based)

I know these cameras do not have the IR problem:

Sony SD camcorders - VX2000, VX2100, PD150, PD170
HD - HVR V1U

I'm interested in possibly purchasing a Sony HVR V5U camcorder, how is the quality compared to the eX? Does anyone know if it has IR problems?
Thanks very much,
Asaf
 
JDDalllas said:
If it's CMOS you have IR trouble if CCD you don't.
Click to expand...
Yeah, not true, it's not the sensor that's causing the problem, it's the strength of the IR filtration in front of the sensor.

The VariCam is a CCD product, yet it's sensitive to IR. The HPX300 is a CMOS camera, but it doesn't have any problem with IR.
 
And I am fond of quoting my story of shooting the keynote at MacWorld 2008 with an HVX200-- and trying edit footage of Steve Job's brown turtleneck.

IR contamination is not confined to CMOS devices.
 
IR = Infra Red
A part of the light spectrum that our eyes are not sensitive too (we can't see it) but digital sensors are sensitive too.

Cameras have a IR filter in front of the sensor to filter out this light, which contaminates the image if not correctly filtered.

If the IR light gets through and contaminates the image, the image is no longer colour accurate. Colours can not simply be 'fixed in post' such you might with an incorrect white balance.

I simply do not see the point of using a 3 chip sensor arrangement, which is designed to capture the most accurate colours possible, if the cameras design simply lets IR light though to instead make the camera accurately capture the incorrect colours.

How would we take it if after taking an accurate 'white balance' on a grey card, some of our whites had a clear blue tint to them due to UV contamination?????

If manufacturers are going to allow this to happen, it should be clearly stated in their specifications and not hidden.
 
What situations show this IR contamination? I've seen a lot of Cool looking EX1 footage, and I'm buying the camera. So is that a situation I should avoid when using this camera?
 
Typically when the dominant light source is a heat source (toungsten, full sun). Not fluro or LED.

It also depends a lot on the material you are shooting. This is problematic if, in stage concerts you have a number of black costumes on stage made in different materials (quite common when each person has to make their own costume, or extra costumes are added at a later stage to an origonal set), then some may stay black when some go muddy brown.

Another time I have seen is the likes of a orcestra, where everyone wears black but buys their own costume. In the footage the colours of the clothes will look like a mess of different blacks and browns.
 
I tested my EX with some black cordura nylon. The IR contamination showed up in diffused daylight indoors as well as under flourescents and tungsten.
 
I wouldn't think fluros would give a problem unless there was mixed lighting. The fluros should have very minimal IR in themselves. Was there mixed lighting?

The video on my site below of the EX-V battery adaptor review was shot in a dark room purely with kino type cheap knock offs, and my black shirt looks just fine.
 
looks promising but there is a half stop loss, which isn't so bad as the sensitivity is pretty good anyway.

Sony should be replacing the filter wheel with filters with these dye in it and adjusting the default colour balance settings to account for the green shift.
 
I posted a very quick test showing the effect of the Schneider/B&W 486 filter:
http://www.vimeo.com/4791723

It cleaned up all the black fabric objects in the shot except for the one that didn't turn amber to begin with. I took it outside to day in the sun and the tripod bag turned amber again but the 486 fixed it. Still not happy about that slight green tint, though.
 
Seems like this Tiffen will not have the green vignetting problem but does have an overall green cast problem, which is ok if you are taking a white balance, but not good if you are dialing in a preset colour temp in the picture profile. We may have to work out a colour adjustment in the PP to correct the green tint to keep the manual dial in WB accurate.

Sony, do you see the mess you have made with this?
 
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