Fire is colored flashes that we observe in colorless diamond. Perceived Fire strength depends on colored flashes quantity, size, duration, brightness, saturation and distribution.
Fire is the simultaneous (local) contrast of colour that is observed in a diamond. The contrast of this colored image depends on surrounding areas and on the duration of a colored flash.
If the colored flash is too fast the eye is not able to comprehend its colour and such a flash is perceived as scintillation. If the colored flash lasts too long its total contrast is less than the sum of the contrast of two separate shorter colored flashes of half the lifetime of the initial flash.
For a flash to be perceived as colored it should not be neither too fast, too small or too bright; when combined these factors make a colored flash appears to a human as scintillation and not a fire flash.
Fire is colored flashes that we observe in colorless diamond. Perceived Fire strength depends on colored flashes quantity, size, duration, brightness, saturation and distribution.
Fire is the simultaneous (local) contrast of colour that is observed in a diamond. The contrast of this colored image depends on surrounding areas and on the duration of a colored flash.
If the colored flash is too fast the eye is not able to comprehend its colour and such a flash is perceived as scintillation. If the colored flash lasts too long its total contrast is less than the sum of the contrast of two separate shorter colored flashes of half the lifetime of the initial flash.
For a flash to be perceived as colored it should not be neither too fast, too small or too bright; when combined these factors make a colored flash appears to a human as scintillation and not a fire flash.
Diamond with the same weight can have different visible size depending on their shape. This visual size is described by spread characteristic. Positive spread means that diamond looks larger than Tolkowsky round with same weight, negative means opposite.
In Spread v2, the formula for calculating the relative Spread has been modified so that the resulting value is directly proportional to the absolute Spread, which makes the result more intuitive.
Diamond with the same weight can have different visible size depending on their shape. This visual size is described by spread characteristic. Positive spread means that diamond looks larger than Tolkowsky round with same weight, negative means opposite.
In Spread v2, the formula for calculating the relative Spread has been modified so that the resulting value is directly proportional to the absolute Spread, which makes the result more intuitive.