If you are only grading under DaVinci Resolve, you should probably go directly to 
Blackmagic panel solutions.
However, if you also have alternative grading programs in your usage pool you have to look for alternatives. For example, the recently introduced Tangent Wave2 Color Grading Panel. For 750 Euro (plus VAT) the Wave2 offers an extensive selection of controls on a relatively compact footprint (approx. 39 x 29 cm, at max. 5cm height):
The high-resolution, white OLED displays for designating the multifunctional control elements can only be found on far more expensive models on the market. Appropriate configuration files for OLED labels are to be provided for many popular grading- and editing programs. At the start of delivery in May 2018, the press release promises, among other things, Premiere Pro and Resolve. With the Tangent Mapper you can even take the adaptation to special software in an emergency into your own hands.
The Wave2 is connected via a single USB port, which also supplies the panel with power at the same time.
If you compare the range of controllers with the competition, the Wave2 currently represents a real price-performance sensation. We are curious what haptic quality one can expect from Tangent here.
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