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Gamma correction is not worth to do and it can give wrong results.
Gamma correction was used in old TV stations when TV sets were made with valves.
Today a well calibrated computer monitor is already gamma corrected and LCD monitors don't behave as a cathode ray tube and nothing need to be corrected.

uh....

Laurie

Sheesh, they just don't get it, do they, Laurie? Why is it so hard to understand? Poser needs linear data to process colour correctly. Has nothing to do with monitor calibration.

A very short explanation.

1- Gamma correction came from the old B&W TV days.
2- TV cameras work in a linear region and have a linear response to light.
3- In those days TV receivers only used cathode ray tubes.
4- A cathode ray tube must work between black and white levels and due to this it has a not linear response to the received signal.
5- To have a linear response the non linear response must be corrected, this was called gamma correction.
6- So each TV receiver must have a gamma correction fitted to its cathode ray tube.
7- TV receivers used valves, no transistors or integrated circuits existed in those days.
8- To make gamma correction it would be make very expensive the TV receivers.
9- So TV receivers were let without correction and the correction was made in the TV station.
10- The amount of correction depend on the cathode ray tube and the level of brightness, so it is impossible for a TV transmitter to make and exactct correction for all receivers.
11- So the correction done by the TV station is only an approximation based on an average value.
12- With color TV the situation became even worst because the cathode ray tube has three cannons, one for each color.
13- The errors of the correction are even worst, because the signal must be received by B&W and color TV receivers.

This were the old days and continue to be in this way for decades. With computer monitors and current technologies things have changed.

14- Today exist integrated circuits and microprocessors.
15- It is possible to make the gamma correction in the monitor and is cheap.
16- The correction is exact because the fabricant can fit the characteristics of the cathode ray tube he is using and also it can track the intensity levels that you use.
15- Computer monitors are not used to watch TV (well...not always true), it are used with linear data, so a good monitor has all the internal correction to output this linear data.
16- LCD monitors even don't need to have this internal correction.
17- Cheap monitors don't have internal correction.
18- Video cards also have a correction that you can adjust, only an approximation because it doesn't fit the cathode ray tube you use and the intensity levels.
19- You can calibrate the monitor so it can have a linear response to signal levels.
20- The correct calibration is with a luxmeter, eye calibration is not correct.

Well, in practice, nobody cares on calibration, each one adjust in a way he/she likes and the same image in different monitors doesn't look the same.

Stupidity also evolves!