Greetings. I purchased this fine scope to use in NRA High Power & Service Rifle Competition. I went with the 100 mm objective because I need to be able to CLEARLY see .30 cal. bullet holes at 300 yards without necessarily going to the maximum magnification. Talk about clear...when I tested the resolution on tree limbs at 300-350 yards distant from my position, I not only saw razor-sharp tree bark outline but razor-sharp leaves as well. In fact, the resolution is far better than any other scope I've ever looked through in this price range. These 48 year old pair of eyes were able to CLEARLY see ants and various other insects plying the branches 300 yards distant on max. power setting (67X). That's correct folks; clearly defined ants, flys, etc., @ 300 YARDS!...not semi-fuzzy little moving blurs. In fact, I was able to CLEARLY see them and identify them down to the 50X power setting. Color resolution is also excellent. Eye placement is critical when you go much beyond 45X but especially so at/near max. power because you're dealing with very short eye relief and an exit pupil of about 1.25 to 1.50mm's. Optical resolution is incredibly sharp to about 90% of the field with only very, very slight decline at the outer edge of the field. You'll be able to clearly spot and see, with near perfect color resolution, the eyebrow feathers of a Cocaided Woodpecker @ 300 yards, never mind clearly defined .30 cal. bullet holes. YOU ARE going to need a very steady tripod/stand for this scope, preferably one that has a 90 degree strong tilt collar to use at ground level. Best damn spotter for the price I've ever looked through...and I've looked through quite a few of them folks. You're not going to beat this performance package for the price!!!