What is the difference between first and second focal plane?
The reticle is the crosshair or scale visible inside a riflescope. Its position within the scope determines how it behaves when magnification changes. There are two basic arrangements: first focal plane, abbreviated FFP, and second focal plane, abbreviated SFP.
The reticle is the crosshair or scale visible inside a riflescope. Its position within the scope determines how it behaves when magnification changes. There are two basic arrangements: first focal plane, abbreviated FFP, and second focal plane, abbreviated SFP.
In the first focal plane, the target image and reticle grow or shrink together. The relationship between a reticle mark and an object in the image stays the same. In the second focal plane, only the target image grows or shrinks. The reticle continues to look the same size to your eye. The angular values of its scale therefore usually apply at a particular magnification specified by the manufacturer.
Neither arrangement is automatically of higher quality. Line thickness, labelling, contrast and illumination also affect how clearly you can see the reticle. Very fine lines can be hard to see when displayed small. Thick lines can obscure image details. A reticle drawing to scale explains these characteristics better than an exterior product photograph.