Apparently the formula for the Astronomik CLS has changed.
Here you can see a custom WB frame taken for each filter in direct sunlight using sunlight white balance setting on the Hap Griffin Baader Modded Canon 350D. All these frames were taken on the same afternoon 3-20-2008.
The old 2" CLS filter give a WB frame that is pink, while the new front "clip" CLS filter gives a cyan tint.
This cyan color looks something like the WB frame through the 2" CLS filter in the old unmodded 30D.
What this means, I am not sure. As of the afternoon of these pictures, I haven't taken any astro-images with the new CLS front filter.
© Hunter Wilson