Here is a nice little listing of the pros and cons of all the systems:
NTSC Advantages-
Higher Frame Rate - Use of 30 frames per second (really 29.97) reduces visible flicker.
Atomic Colour Edits - With NTSC it is possible to edit at any 4 field boundary point without disturbing the colour signal.
Less inherent picture noise - Almost all pieces of video equipment achieve better signal to noise characteristics in their NTSC form than in their PAL.
NTSC Disadvantages
Lower Number of Scan Lines - Reduced clarity on large screen TVs, line structure more visible.
Smaller Luminance Signal Bandwidth - Due to the placing of the colour sub-carrier at 3.58MHz, picture defects such as moire, cross-colour, and dot interference become more pronounced. This is because of the greater likelihood of interaction with the monochrome picture signal at the lower sub-carrier frequency.
Susceptablity to Hue Fluctuation - Variations in the colour subcarrier phase cause shifts in the displayed colour, requiring that the TV receivers be equiped with a Hue adjustment to compensate.
Lower Gamma Ratio - The gamma value for NTSC is set at 2.2 as opposed to the slightly higher 2.8 defined for PAL. This means that PAL can produce pictures of greater contrast.
Undesirable Automatic Features - Many NTSC TV receivers feature an Auto-Tint circuit to make hue fluctuations less visible to uncritical viewers. This circuit changes all colours approximating to flesh tone into a "standard" fleshtone, thus hiding the effects of hue fluctuation. This does mean however that a certain range of colour shades cannot be displayed correctly by these sets. Up-market models often have this (mis)feature switchable, cheaper sets do not.
PAL Advantages
Greater Number of Scan Lines - more picture detail.
Wider Luminance Signal Bandwidth - The placing of the colour Sub-Carrier at 4.43MHz allows a larger bandwidth of monochrome information to be reproduced than with NTSC.
Stable Hues - Due to reversal of sub-carrier phase on alternate lines, any phase error will be corrected by an equal and oposite error on the next line, correcting the original error. In early PAL implementations it was left to the low resolution of the human eye\'s colour abilities to provide the averaging effect; it is now done with a delay line.
Higher Gamma Ratio - The gamma value for PAL is set at 2.8 as opposed to the lower 2.2 figure of NTSC. This permits a higher level of contrast than on NTSC signals. This is particularly noticable when using multi-standard equipment as the contrast and brightness settings need to be changed to give a similar look to signals of the two formats.
PAL Disadvantages
More Flicker - Due to the lower frame rate, flicker is more noticable on PAL transmissions; particularly so for people used to viewing NTSC signals.
Lower Signal to Noise Ratio - The higher bandwidth requirements cause PAL equipment to have slightly worse signal to noise performance than it\'s equivalent
SECAM Advantages
Stable Hues and Constant Saturation - SECAM shares with PAL the ability to render images with the correct hue, and goes a step further in ensuring consistant saturation of colour as well.
Higher Number of Scan Lines - SECAM shares with PAL, the higher number of scan lines than NTSC.
SECAM Disadvantages
Greater Flicker - (See PAL)
Mixing of two synchronous SECAM colour signals is not possible - Most TV studios in SECAM countries originate in PAL and transcode prior to broadcasting. More advanced home systems such as SuperVHS, Hi-8, and LaserDisc work internally in PAL and transcode on replay in SECAM market models.
Patterning Effects - The FM subcarrier causes patterning effects even on non-coloured objects.
Lower monochrome Bandwidth - Due to one of the two colour sub-carriers being at 4.25MHz (in the French Version), a lower bandwith of monochrome signal can be carried.
Incompatibility between different versions of SECAM - SECAM being at least partially politically inspired, has a wide range of variants, many of which are incompatible with each other. For example between French SECAM with uses FM subcarrier, and MESECAM which uses an AM subcarrier
Now you know and we all know that is half the battle. YOOO-JOE!!!
