Here is a photo of the NF Direct Mount. If this is the mount you are talking about then NO you will not be able to add the ADIMT (Angle Degree Indicator) nor a bubble level.
Also I would recommend getting the 50mm over the 56mm because you will not really notice the difference.
The average size of a human’s eye pupil at night is 7 mm and in daylight it is about 4mm on average. If the optic give you a 7mm of exit pupil and you are using it for day use more than half the light will not reach the retina. I have also noticed if you are getting too much light and you look away you see light spots were ever you look and the targets look washedout. On a lot of my scopes I use a light reducer so I do not get the light spots and the washout is not there.
Size of bell divided by magnification = exitpupil. Hare are some examples.
The sweet spots for the 56 and the 50mm at Night and Day use.
50/7.14x = 7mm night use and for day use 50/12.5x = 4mm
56/8x = 7mm night use and for day use 56/14x = 4mm
You are really not get much advantage over the 50mm. I feel there is a bigger disadvantage and that is you have to go with tall rings 1.00” at the low to 1.25” were the 50mm you can do 0.885”.
Hope this helps.
Mike @ CSGW
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