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Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: July/31/2007 at 18:55
ahuebel View Drop Down
Optics Apprentice
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I just got a s&b zenith scope in and I noticed the cross hairs get larger as I zoom in. I guess this means it has an objective focal plane correct? The only other scope I have is an old leopold 3-9 and it appears the crosshairs remain constant. Is it all a matter of preference or is there a good reason to have one over the other?

 

 

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: July/31/2007 at 19:14
spreader View Drop Down
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It's a matter of preference and there is a good reason for it:

When your reticle changes in size when you go through magnification range - it means your reticle is in first image plane (sometimes referred to as focal plane).

If reticle size doesn't change through magnification range it means it's in second image plane.

When you're using MilDot reticle for example it's pretty helpful when reticle is in first image plane - it changes size as you go through magnification range, but it can be used at any magnification for ranging purposes.

When your reticle is in second image plane, with mildot reticles it means it can be properly used only at 10x magnification. At other magnifications you have to run calculations to estimate distances. Advantage of having reticle in 2nd image plane sometimes is in fact that it won't obscure small objects as you go through magnification settings. Generally speaking I would say that unless you need MilDot reticle, using reticle in 2nd image plane makes more sense and that's what is usually found on hunting/sporting scopes. In general though it is a matter of preference.

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: July/31/2007 at 21:08
RifleDude View Drop Down
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Another advantage to the FFP reticle is visibility in low light.  You can dial up the magnification and the reticle becomes bolder and easier to see against a dark background.  Secondly, the FFP reticle theoretically holds zero better because it can't be affected by movement in the zoom tube as magnification changes.  With some SFP scopes, point of impact will shift some when changing magnification.

 

Basically, I like FFP reticles better for big game hunting where the best shot opportunities is often in low light and SFP reticles better for varmint and target shooting, where I want the least amount of the target obscured as possible.  Most 30mm tube European scopes have FFP reticles and most 1" tube scopes have SFP reticles.

Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: July/31/2007 at 21:15
ahuebel View Drop Down
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Well I wonder if I should have selected a different reticle. I got the #9 but it was not founded on any personal experience. I won't really know if I like it or not until I use it for a while. By that time I guess it will be too late.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: July/31/2007 at 21:33
RifleDude View Drop Down
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I personally like the #9 -- bold posts at 3:00, 6:00, and 9:00 for visibility, yet thin center lines for precision aiming.  It's much like a # 4, except with the addition of the circle.
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