What is a good color to darken and lighten your average dark yellow paint for highlights and shadows...I remember seeing somewhere that you shouldn't use black and white for shadows and highlights

Hi Michael

Use a medium to dark brown and a buff ivory for mid range colour changes.

I use Tamiya Buff as the base colour for German base colour (and desert colours) rather than Dark yellow as any wash (or filter) will darken the yellow more anyway.

Deck tan and buff are great for dark yellow tinting. Ive even seen Clear Yellow being used to tonal shift dark yellow

Depends on your artistic style. My personal preference is to start with a fairly light base coat or camo and gradually darken with oils/filters. Low lights are done separately with oils.

So to answer your question more directly, for dunkelgelb, one way to do it is to use a yellow cut with white for base and high lights, and use sienna and umber oils for low lights. Tan or brown filters will also darken the overall model.

In the past, I used white (actually about 30% DY to 70% white) to get a tone I liked. However, this makes the color rather bland. Adding small amounts of Clear Yellow to the mix brings it back into the "yellow" shade. To darken, some Flat Earth and/or Khaki could be used. These of course all being Tamiya colors.

You can also skip the process entirely and go for pre-mixed shades, such as this reference from AMMO http://www.migjimenez.com/en/modulation-sets/338-dunkelgelb-modulation-set.html