Thanks Krazyman, I saw them in NikonUSA website. The issue is I have to bring my setup down to test which correction dioter suits me in order to buy. I guess have to get my eyesight corrected by a optician.
An optician checks your eyes for normal reading distance. The virtual distance in the viewfinder may not be exactly the same. Having said that, it doesn't matter that much even if you didn't get the exact match diopter since you can still compensate with the build-in adjustment.
most recommendation on adjusting diopter is to throw the focus completely off,
eg. pointing on a clear white sky with focus at minimum.
and adjust the diopter until the etch line on the focus screen is as sharp as possible.
