German Panzer Colors
In March of 1941, vehicles in and destined for North Africa were painted in yellow brown/sand yellow (RAL 8000) as a base color with grey green (RAL 7008) for camouflage patterns. Yellow brown was to be used to cover 75% of the vehicle and grey green the rest. In the field, vehicles were often camouflaged with mud and captured British paints.

1939-41 1941 1942
In December of 1942, Tigers in Tunisa were painted overall dark gray with a thin coat of dark olive green (RAL 6003) sprayed over them. In February of 1943, by the order of OKH, dark grey was replaced by dark yellow (RAL 7028) as the base color for all German vehicles. For camouflage patterns dark olive green (RAL 6003) and red brown (RAL 8017) were to be used.

1942 1943

1943-44 1943-44
Lastly, in regards to the National Insignia (German Cross) and Numbers. Though common early in the war, with the introduction of the tri-color paint scheme (1943), the use of symbols, numbers and other forms of identification, especially on wheeled vehicles and half-tracks began to decline. This appears to have been done due to the lack of paint or to deny the enemy vital military intelligence or in some cases, both. By the spring of 1944, especially following D-Day, when Allied airpower dominated the skies over Europe, the use of any forms of unit, national or numerical identification became even more rare.

Late 1944-45 Late 1944-45
How standardized were all these changes ? On the planning table they may have looked well. However, these varied greatly "on the line", as paint color differed from batch to batch and the application in the field varied even more greatly. Many tanks retained only their factory dark yellow (RAL 7028) color with camouflage consisting of mud, soot, netting and foliage. A "pristine paint scheme" in the field? Hardly, as these (regardless of type) were far from the norm on the battleline.
Panzer prints courtesy of http://www.rtvmodeler.com/Guiatanques/colorespanzer.htm