Ultra-wide lenses need very large filters to be able to cover the entire angle of vision, this leads manufacturers to design filter holders of considerable dimensions that sometimes even produce slight vignetting and do not allow 100% use of the lens focal length.
Some manufacturers like Sigma o Canon have provided their lenses with special slots to mount filters of very small dimensions as they are mounted on the back of the lens, inside the bayonet that connects the lens to the camera.
The advantage of this assembly is easy to see, firstly by the size of the filters that we are handling, total absence of vignetting or light entry, manageability (filters the size of a postage stamp) and price.
They also have disadvantages that must be named, some lenses must be removed from the body to insert the filter, this depends on what atmospheric situation we are in, it can be a setback. On the other hand, we will not be able to use gradients or polarizers, and this must also be taken into account when acquiring this type of filters.
WHAT LENSES ARE COMPATIBLE?
Sigma 14-24Sony E y Leica L Mount
Sigma 14-24mm F2.8 lens (Sony mount)
Sigma 14-24mm F2.8 lens (Leica L mount)
Sigma 14-24Nikon Mount
Sigma 14-24mm F2.8 lens (Nikon 14-24mm F2.8G ED)
Canon 11-24 f4
Canon EF 11-24mm f/4L USM
Canon EF 14mm f/2.8 II USM
Canon EF 8-15mm/f4L USM fisheye
Canon EF 15mm/f2.8L Fisheye
Canon EF 16-35mm/f2.8L USM (Version 1)
Canon EF 17-35mm/f2.8L USM
Canon EF 17-40mm/f4L USM
Sigma 14-24Canon Mount
Sigma 14-24mm F2.8 DG HSM (Canon mount)
Sigma 14mm F1.8 DG HSM (Canon mount)
Tamron SP15-30mm f/2.8 DI VC USD（A012) (Canon mount)
Tamron SP15-30mm F/2.8 Di VC USD G2 (Canon mount)
Sigma 12-24mm F4 DG HSM (Canon mount)
Canon TS-E 17mm f/4L (Some parameters will have vignetting)
