Blogs
APHA = Pt-Co = Hazen = PCU = Platinum Cobalt Color
Posted on by Ganesh Ramanathan
“APHA” stands for American Public Health Association Color Scale, the organization responsible for the original definition and implementation of this visual color scale as a standard method for rating water quality. Ganesh Ramanathan
APHA/Pt-Co/Hazen vs Gardner color scales: What’s the difference?
Posted on by Ganesh Ramanathan
The APHA/Pt-Co/Hazen and Gardner visual color scales were both originally based on liquid chloroplatinate color standards but have different history and intended use. Ganesh Ramanathan
Where does one find the EP (European Pharmacopoeia) Liquid Color Matching Standards?
Posted on by Ganesh Ramanathan
EP – European Pharmacopoeia Color is a visual liquid color scale used primarily in the pharmaceutical industry. It consists of 3 primary color standard solutions (yellow, red and blue) mixed with hydrochloric acid to make 5 standard color solutions – B (brown), BY (brownish-yellow), Y (yellow), GY (greenish-yellow) and R (red). Ganesh Ramanathan
Do HunterLab sphere instruments conform to ASTM D1003?
Posted on by Ganesh Ramanathan
Yes, but note there are two different approved instrument geometries cited in the ASTM 1003 method. Ganesh Ramanathan
Is there an Internet Site for converting and displaying color values?
Posted on by Ganesh Ramanathan
FAQ: “… Was wondering – do you know of a web site or application where if CIELAB values were entered, the corresponding color would be displayed? Can I also convert from one color scale to another?” Ganesh Ramanathan
Optimal inter-instrument agreement and communication of color values
Posted on by Ganesh Ramanathan
To communicate color values effectively, completely specify the 6 parameters of your measurement method and verify that your color measurement is repeatable. These are the key factors to ensure inter-instrument agreement. The best inter-instrument agreement in color measurement at multiple locations occurs when a product is measured with the same instrument model from the same […]
What is the Hunter Rd, a, b Color Scale?
Posted on by Ganesh Ramanathan
The Hunter Rdab opponent-color scale, developed in 1943, was an early version of the Hunter L, a, b scale. Instead of L, Rd is used to designate lightness and is identical to the CIE Y Brightness/Luminosity value. Sometimes the Rd, a, b color scale is shown as LRd, aRd, bRd. Ganesh Ramanathan
What are the NCI National Cheese Color Standards?
Posted on by Ganesh Ramanathan
Ganesh Ramanathan
What Path Length Cell should I use for APHA/Pt-Co/Hazen Color Measurement?
Posted on by Ganesh Ramanathan
FAQ: ” We are currently using a 10 mm path length and read in the 0 – 50 region for APHA/Pt-Co/Hazen Color, usually in the area of 10. Would you recommend a 10 mm path length with our equipment for this application?” Ganesh Ramanathan
Do you have a formula to convert Hunter Lab values to CIE L*a*b*?
Posted on by Ganesh Ramanathan
FAQ: “Do you have a formula to calculate Hunter L, a, b values from CIE L*, a*, b* values?” Ganesh Ramanathan
Is there a Munsell HVC color conversion in EasyMatch QC?
Posted on by Ganesh Ramanathan
FAQ: “Do you offer a Munsell HVC color conversion in your EasyMatch QC software?” Ganesh Ramanathan