Nikonian72 wrote:
Your D800 has a full frame, 35.9 x 24.0 mm CMOS sensor, but you have used digital cropping, significantly reducing active sensore size and pixel count.
What was your Working Distance (lens front element to subject)? I suspect that you can get closer. To prevent "small aperture diffraction", I also recommend that you do not use an aperture smaller than f/16.
I used the Nikon R1 Wireless Close-Up Speedlight System and aperture or shutter speed is not a factor with that system, the closest I could get without spooking the spider was 8-inches.