FlyingStick wrote:in2anity wrote:Just be careful about the diminishing return on investment for high objective lenses- a 50mm objective does let much more light through than a 40mm, so you've got to ask yourself is it really worth the (potentially) huge jump in cost...
Thanks mate.
I think I'm either going the VX1 3-9x50 or the VX2 3-9x40. Tending towards better glass over bigger obj, as well as trying to keep it compact/light.
Going to end up with a better scope on this then my 223 (Vortex Diamondback) lol! I like the Vortex's, but I've looked through a Leupold and my Vortex side by side and felt that Leupold was a better scope (ever so slightly, especially at a distance). I also find a the DB a PITA for eye relief.
Better glass over larger objective is a good idea.
Also, consider that "more light" is really about the exit pupil on the scope, which is a magnification:objective lens ratio rather than a purely objective lens diameter thing (plus quality of glass, of course). An exit pupil of 7mm is ideal. The classic example is a 56mm ob.lens / 8x magnification= 7mm. So a 40mm ob.lens scope set to 6x (or fixed at 6x) give you very close to 7mm (6.666*mm). This gives the maximum coverage to your pupil, which is all the light your eye can gather. The quality of glass then determines the quality and spectrum of that light (put simply in my lay-mans understanding of it all). So, change the ob.lens diameter or the magnification and the amount of light getting through (exit pupil) will change. Anything over 7mm exit pupil is kind'a a waste of time because your eye's pupil will not dilate beyond 7mm. (yes i did just say the same thing twice in two different ways)
Funny you say your Vortex Diamond Back is fussy with eye relief. Mine seem fine.
I have three scopes i use for spotlighting on 22lr and 223rem. Two of those are Vortex Diamondbacks with 40mm ob.lens. I use them set on 6 for spotlighting and have no issue. On longer shots i might turn the 3-9x on the 223rem up to max and still get plenty to see by. The 3-12x on the 22lr gets a bit dim at max but is still usable out to my max range with that rifle. The other is 6x40mm fixed that used to sit on another 22lr and cost $70. It is surprisingly good late in the evening and under light. Probably due to the light travelling through fewer lenses. Usually, 6x is all i need to do the job out to 100m. I find it a good compromise between magnification, field of view and exit pupil.