glow in the dark filament color consistency problem

[neep]

Hi all, I've recently started using some PLA glow in the dark filament. A small print of a simple object worked out okay, but when I printed this larger and more complicated Ganesha statue, I notice that there is significant color inconsistency going on:



Notice how the base is perfectly white and then when it starts on the actual figurine the color starts turning greyish. The glow in the dark effect at these darker spots is also almost gone. I retried with a scaled down version and almost the same effect can be seen. Notably the hat is perfectly white again.

Does anyone have any theory as to why this is happening?

I am using a Felix 3.0 at the following settings:

layer height: 0.1mm
shell thickness: 1.5mm
bottom/top thickness: 1.5mm
fill density: 17.5%
speed: 100mm/s
infill speed: 50mm/s
travel speed: 200mm/s
retraction speed: 50mm/s
retraction distance: 5mm
temperature: 180C
minimal layer time: 30s
slicer: Cura

The filament I used:

http://www.123inkt.nl/123inkt-nl-3D-...84-t43554.html

Thank you very much for any clues!