It is combining Petzval lens and anamorphic technologies. This 58mm f:2 lens is designed to create anamorphic images with swirling bokeh and vignetting in the background. The bokeh rotates around the center of the frame and draws attention to this part, as if the middle is surrounded by concentric circles. This effect becomes even more obvious and interesting when shooting in points of variable light and contrast, for example, in street portraits in low light, against the backdrop of forests and industrial buildings. Vignetting has the same effect as pulling the eye towards the center. The level of bokeh and vignetting is adjusted using a slider on the lens barrel. You can use a lens for FullFrame, APS-C and MFT formats. But you need said your format lens. If you purchase this adapter for full frame, we do not guarantee that it will work in this format. Lens filter diameter is 72 mm. Does not compress the image, only creates anamorphic-like effects.