Im not having that , sorry .
me neither if your gun is set up at whatever distance youset it at you should only be checking your zero
not re adjusting
the thing with shooting using lamp light more so with red filters is you judging the distance cos it can play tricks on your eyes
if your set up at 30 yds in day light it is at night
i personally have found things look further away under the lamp and have give un,needed hold over
thats using fed filters not white light