Flash 1

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Fox_one

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Dave
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Is there some sort of light conversion scale that runs from "Lux /ft.Candles" to "Speed/Aperture" settings?
You know, the sort of thing that goes from "44 Lux to "1/100th @ f8, 100ASA"

I have decided to go back to basics for a bit, re-learn the art, and then start properly on the Canon.
 
By your title, "Flash 1" I assume you're referring to the use of flash, is so.. Guide number. If you have a search for that term you'll find out how it works to calculate based on flash power and distance to subject. Aperture will control the effect flash will have, but shutter speed is primarily for ambient providing you don't exceed the synch speed of the camera.

If this is about general exposures without flash, have a look at the Fred Parker UEC.
 
Use of flash specifically was not uppermost in my mind at the time I wrote (I have a second question labelled Flash 2 for later on).

A modern light meter is, frankly, rather expensive for the amount I'm planning to use it, but there are several models of light-meter giving the result in "lux" or "Foot-Candles" or whatever.

I just wondered if there is a conversion scale to go from "Lux" to something I can use in assessing the manual settings.
 
Fox_one said:
A modern light meter is, frankly, rather expensive for the amount I'm planning to use it
Click to expand...

You can pick-up a secondhand Weston Master for under £20.

A new Sekonic L-208 is under £70.

But with a modern DSLR, you don't really need a lightmeter. Except possibly a flashmeter for studio-type work if you go that route, but even then many will say the histogram and blinkies are more accurate.


The lux/footcandle models, are these reflective or incident? It sounds like these are the type used for monitoring whether illumination is adequate in office and buildings.
 
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If you're looking at old light meters, check that they do flash. Most don't.
 
Foot candles are what are used when shooting theatrical films with continuous lighting. At ISO 100 at 1/50th the following apertures correspond to foot candles:

  • f1.4 = 25 FC
  • f2 = 50 FC
  • f2.8 = 100 FC
  • f4 = 200 FC
  • f5.6 = 400 FC
  • f8 = 800 FC
  • f11 = 1600 FC
 
Just to make sure that you're aware that EV 0 is the equivalent of Iso 100, f/1 for 1 sec. Therefore 1280 Lux -= EV 9 and is 9 stops faster than EV 0 however you wish to achieve it.

Bob
 
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