How does the incident Light meter really work

[norris_watkins]

Im an advanced beginner and have been thinking of buying an incident light meter.
As per my understanding, it will measure the light falling on the subject and would suggest the correct exposure ( Aperture/speed )

But I thought different cameras differ in their sensors sensitivity ( some camera models needs little light whereas some needs a lot of light )
So without knowing the exact camera model, how can teh incident light meter advice on the exposure settings ?

Did I understand the whole thing wrong ?
--nw

 

[tirediron]

All light meters work to a similar standard. In the film days, the industry standard was 18% grey - today it varies a bit, but when you get your meter do a series of test shots comparing the meter's readings to the exposure your see, and you can very quickly figure out what your adjustment factor is, or, with better meters, you can adjust the meter's calibration.

 

[Helen B]

This is one of the main reasons behind having a standardized film / sensor sensitivity rating. It doesn't work perfectly, so it is always advisable to adjust the speed you set the meter to according to your experience after doing a few tests, as titled iron says.

 

[tirediron]

This is one of the main reasons behind having a standardized film / sensor sensitivity rating. It doesn't work perfectly, so it is always advisable to adjust the speed you set the meter to according to your experience after doing a few tests, as titled iron says.

:lmao: :lmao: :lmao: :lmao:

 

[Derrel]

His title is Sir John...Duke of Vancouver Island..and Protector of the Padlocks...
I think that's our moderator from across the pond.. but heck, in reality, I'll answer to 'most anything!

 

[BrianV]

Im an advanced beginner and have been thinking of buying an incident light meter.
As per my understanding, it will measure the light falling on the subject and would suggest the correct exposure ( Aperture/speed )

But I thought different cameras differ in their sensors sensitivity ( some camera models needs little light whereas some needs a lot of light )
So without knowing the exact camera model, how can teh incident light meter advice on the exposure settings ?

Did I understand the whole thing wrong ?
--nw

The camera, whether digital or film, uses "ISO" ratings to describe sensitivity to light. This is also ASA on older cameras/meters, and "Weston" on OLD meters. All of these have the same numerical value. Tri-X film is 400 ISO, ASA, and Weston. In the same light, your digital camera set to ISO 400 uses the same Shutter-Speed and F-stop as TRI-X film would use. I use a "Weston Master" meter.

An incident meter has an opaque white filter over the Photo-sensitive element. It is held in the path of the light falling on your intended subject. Take the meter reading at that spot, and transfer it to the camera using Manual settings for Shutter Speed, F-Stop, and ISO setting. If you are shooting Black and White Film or using a Monochrome Digital camera with Color filters over the lens that absorb light, you must correct the exposure. SO: if shooting black and white film, and using a Yellow filter: need to increase the exposure by 1 F-Stop. The same is true for Polarizers and Neutral density filters used with color and black and white: you must manually correct the exposure when setting the camera.

I get to cheat with this camera. The incident meter is built into the camera.

 

[Helen B]

This is one of the main reasons behind having a standardized film / sensor sensitivity rating. It doesn't work perfectly, so it is always advisable to adjust the speed you set the meter to according to your experience after doing a few tests, as titled iron says.

:lmao: :lmao: :lmao: :lmao:

Truth revealed by the unchecked spell checker.

To go back to Norris' question: Why do you want an incident meter? Can we help you with that decision? You can use any camera meter as a basic incident meter by metering off a known reference, such as a grey card or the palm of your hand. Handheld incident meters improve on this by having a dome-shaped receptor (or similar device like the Weston Invercone) that measures light coming from behind the meter axis, to some extent. Just ask if you want us to go into this some more.