As promised, here is one of the yellow color phase. We found several of these beautiful snakes on our recent trip. I was still missing my tripod at this point and had to brace my camera on my pack and use a large aperture to get this. I refound this snake 2 days later (not 6" away!) and reshot it using a tripod.
Camera Model: Canon EOS 5D
Date/Time: 2008:03:25 107:06
Shutter speed: 1/100 sec
Aperture: 5
Exposure mode: Av
Exposure compensation: +2/3
Flash: Off
Metering mode: Evaluative
Drive mode: Continuous: frame 1
ISO: 640
Lens: EF180mm f/3.5L Macro USM
Focal length: 180mm
AF mode: AI Servo AF
Image size: 4368 x 2912
Image quality: Raw
White balance: Auto
What a beautiful snake, Milo. Great sharpness around the head. I'm not sure if more DOF would have helped here - it may have just brought out more detail in the background. The OOF stem in the lower left corner is a bit distracting though there was probably little you could do about that in the field.
My God that is some scary looking snake! Focus is spot on where it should be. I am not sure what to think of the composition as a whole though, maybe a horizontal or a different position would have resulted in something better.