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The Novo-Gloss compensates for reflection from within the coating for highly reflective pigments,
metallic coatings and speciality pigments, allowing the haze of any painted surface to be measured.
Measuring Haze with the Novo-Gloss 20/60/85 with Haze
Gloss Haze values can be calculated using two ASTM test methods –
ASTM E430 – using defined angular tolerances around the 20 degree specular angle
ASTM D4039 – using the calculated difference between measured gloss values at 20 and
60 degrees (H = G
60
– G
20
). This method is only suitable for non-metallic samples having a
gloss value of greater than 70GU at 60 degrees (values below this are still calculated but
the haze value is displayed in red).
The instrument can display the natural haze value (HU) or Log Haze Value (HU
LOG
).
When measuring haze values, higher numbers indicate a lower quality surface.
A high gloss surface with zero haze has a deep reflection image with high contrast.
Log Haze Values are commonly quoted for paints and coatings as this scale has better
corroboration with human perception of surface quality.
Haze Compensation
Reflection haze is caused by micro texture
on a surface which causes a small amount
of light to be reflected adjacent to the gloss angle. For white surfaces, bright colours
and metallics, a certain amount of diffuse light, reflected from within the material, is
also present in this region.
This diffuse light exagerates the haze signal for these surfaces causing higher than
expected readings.
*This is option only available on the Novo-Gloss 20/60/85 with Haze
Gloss and Haze
component
Yellow pigment in
paint film
Diffuse light
Incident light
