light purple dyes

[peeps]

i just got my bealls..they burn fine...at 2x and play fine..,but i noticed that the dye is so light.....does a darker purple mean it's a better dye?

[Faustus]

The color changes based on the chemical makeup of the dye. So no the color does not ALWAYS mean anything. Depends on the type of ink.

[garryheather]

To be more specific, the optical block on the DVD player / ROM is tuned to a specific wavelength whereas your eye covers a much wider spectrum.

So long as a predetermined amount of reflectivity comes off of the disc, the player only sees the data and doesn't care what colour the disc is.

True however, that some dyes (and other component parts) will be better quality than other for longetivity and the like, and you might find some more compatible than others. But you can not judge this solely by the colour of the recording surface.

[Faustus]

Right, it has more to do with the reflectivity of the disk right?

[garryheather]

Broadly speaking, yes - don't forget that the DVD player "sees" differently to you and I, so you might look at a disc and think it makes a pretty good mirror, but if it doesn't demonstrate clearly to the player what is the burnt equivalent of a pit and a land, then the reflectivity won't be good enough for the player to interpret that accurately.

The reflective layer used, it's uniformity and that of the dye, all contribute. As does the composition of the plastics used to actually make the body of the blank. All it needs is an impurity or other such manufacturing error to come into it, and we're stuffed.

The reflectivity issue is best decscibed using a CD player as an example - the laser used in a CD player is in the infra-red spectrum, and therefore completely invisible to you and me. The disc must reflect this very fine wavelength, so the colour of the disc, which falls into the visible spectrum that we CAN see, is neither here nor there. It simply does not matter.

So basically, if you bought one of those green pens and drew around all your CD's a few years back, you were ripped off !

[drewson99]

in my experiences with DVD-R media, the richer, deeper purples have been more compatible with more players, where the very light almost pink bottoms only play on my APEX.