LRE using false color
Jan 17, 2019 06:43:34 #
I've just bought a field monitor (andycine) and it has a few interesting features it has built in focus peaking it has zebra striping which shows what's getting over exposed. framing, zooming and false color.
False color is measured in LRE but what's LRE?
An IRE is a unit used in the measurement of composite video signals. Its name is derived from the initials of the Institute of Radio Engineers. A value of 100 IRE was originally defined to be the range from blanking level to peak white in a video signal.
This is something commonly used by video and filmmakers but it is applicable to stills photography too.
We tend to consider the lighting of our subjects first less on the background and tend to make a flying leap when it comes to highlights and shadows. If you are shooting a portrait a big difference between light and shade on someones face will give more of a film noir look too flat and its looking bland. Prior to false color you pretty much had to work with a light meter to set things up as you wanted.
Contrast ratio:
in LRE its pretty easy measure the value in one area and measure in another area e.g 80 highlight and 20 shadow just divide 80/20 = 4:1
but we are more used to f-stops so in this case 40 is one stop down from 80 and 20 is one stop down from 40 so the difference between 80 and 20 is 2 stops.
So knowing what the contrast ratio is in one image can help you create photos with similar contrast ratios and get the look you want. incidentally a LRE value around 70 is pretty good for skin tones.
Led lighting can be bought quite cheaply these days and it's pretty lightweight gear and effective.
Since the field monitor is Hdmi it also can be plugged into most computers so you might use it as a secondary display while dodging and burning.
There are a few videos on youtube which go into detail about lighting and false color, i may link to some later. It's worth looking at still and video footage to see what lighting you like so you can apply it to your own work.
False color is measured in LRE but what's LRE?
An IRE is a unit used in the measurement of composite video signals. Its name is derived from the initials of the Institute of Radio Engineers. A value of 100 IRE was originally defined to be the range from blanking level to peak white in a video signal.
This is something commonly used by video and filmmakers but it is applicable to stills photography too.
We tend to consider the lighting of our subjects first less on the background and tend to make a flying leap when it comes to highlights and shadows. If you are shooting a portrait a big difference between light and shade on someones face will give more of a film noir look too flat and its looking bland. Prior to false color you pretty much had to work with a light meter to set things up as you wanted.
Contrast ratio:
in LRE its pretty easy measure the value in one area and measure in another area e.g 80 highlight and 20 shadow just divide 80/20 = 4:1
but we are more used to f-stops so in this case 40 is one stop down from 80 and 20 is one stop down from 40 so the difference between 80 and 20 is 2 stops.
So knowing what the contrast ratio is in one image can help you create photos with similar contrast ratios and get the look you want. incidentally a LRE value around 70 is pretty good for skin tones.
Led lighting can be bought quite cheaply these days and it's pretty lightweight gear and effective.
Since the field monitor is Hdmi it also can be plugged into most computers so you might use it as a secondary display while dodging and burning.
There are a few videos on youtube which go into detail about lighting and false color, i may link to some later. It's worth looking at still and video footage to see what lighting you like so you can apply it to your own work.
Jan 17, 2019 08:50:38 #
Blackest, you have set me off on a search... oh well retired...
Found Pseudo color based on grayscale. Here is a program for creating pseudocolor. The HTML below contains the link for the download.
https://web.archive.org/web/20100611230338/http://neuron2.net/pseudocolor/maker.html
Found Pseudo color based on grayscale. Here is a program for creating pseudocolor. The HTML below contains the link for the download.
https://web.archive.org/web/20100611230338/http://neuron2.net/pseudocolor/maker.html
Jan 17, 2019 10:18:45 #
dpullum wrote:
Blackest, you have set me off on a search... oh well retired...
Found Pseudo color based on grayscale. Here is a program for creating pseudocolor. The HTML below contains the link for the download.
https://web.archive.org/web/20100611230338/http://neuron2.net/pseudocolor/maker.html
Found Pseudo color based on grayscale. Here is a program for creating pseudocolor. The HTML below contains the link for the download.
https://web.archive.org/web/20100611230338/http://neuron2.net/pseudocolor/maker.html
not quite the same thing here are 3 parts that help explain it.
https://www.youtube.com/watch?v=vmLVlZwpOSM this you can skip if you are not interested in video.
https://www.youtube.com/watch?v=k0bsXMlNxf8 The principle ideas.
https://www.youtube.com/watch?v=NHnRwR76E6Y putting it into practice.
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