What are SFP and FFP?
The vast majority of Riflescope are SFP (Second Focus Plane).
This means that the reticle(line of sight)is engraved on the eyepiece at the back, SO that the size of the reticle is fixed and does not change with the magnification. The advantage is that the reticle size can be good, the thickness is just right.The disadvantage is that the function of reticle is generally only used at the highest magnification. (It can be used at low magnification, but the calculation is very troublesome)
The FFP is much more expensive than the SFP with the same lens. The reticle is engraved on the front objective and changes with the magnification. The advantage is that the reticle function can be used at all magnification, the disadvantage is that at low magnification the reticle appears small, especially in bright light, which is very difficult to see. If you choose an FFP Riflescope, it is recommended to choose one with lighting.
The reticle of FFP varies with magnification, while the size of SFP is fixed. Common sniper scope reticle. Plain Crosshair, the simplest cross reticle.Is not recommended. Too coarse partition will cover the target, affect the accuracy; It's too fine to see in complex environments, like jungle or bright light.Duplex, improved on Plain Crosshair, has a thin line of sight in the middle and thick around the sides, which not only makes up for the shortcomings of the above cross reticle, but also makes the eyes focus on the center of alignment.And can be used as a simple dense site according to the length of the thick and thin reticle.