Okay, let's get one thing out of the way. It is unlikely that you'll get Cooke Cine Prime quality on a smartphone. But what you can expect is that there are some reslly good add on lenses out there for phones, and some not so great ones. We were sent Sandmarc's 16mm wide lens along with its new hybrid filters to give a run through to see if they live up to the hype.
The 16mm lens
Sandmarc's 16mm lens is designed to give your iPhone an ultrawide option that it might otherwise not have. According to the specifications it is a premium multi-coated affair, and on the iPhone XS on which I tried it, gives a 2x wider angle than the standard built in lens.
The build quality of the Sandmarc 16mm lens is very good indeed.
Just like Sandmarc's anamorphic lens, which we tested previously, the 16mm wide is built really nicely. This is a quality product, with a nice weight, and no plastic to be seen. It comes complete with a protective lens cap for the front and rear elements to protect it during transportation, and a soft pouch to keep it in.
The supplied lens came with a protective case for the phone, which comes with two threaded ports for each back facing phone camera that the lens can screw into. Again this case is nicely built and looks good. It's low enough profile and good looking enough to keep on your phone as its main protective case. The only niggle I have with it is that dust does appear to collect near the lenses with it, so I did find myself having to periodically take it off to clean around them. So it is as well to check before mounting the lens onto it so you don't end up with dust spots in your shot, particularly if you are shooting into the sun!
The lens screws on easily enough, although it can take a few moments to get the right first alignment to get it to screw on smoothly. But once this is done it mounts easily.
The hybrid filters
The hybrid filters are NDs combined with a polariser. These come nicely packaged in a flip out soft pouch and consist of ND16, ND32, and ND64 flavours.
The Hybrid filters have a nice, smooth rotation with good dampening for the polarisation adjustment
Just like the lens these are made from quality multi-coated optical glass, and are clearly not 'toy' filters. The polariser rotation action is smooth and well dampened. If I had one gripe with them it is that they do not come with a protective cap, which means that you can't just mount a filter and then easily put the phone inside a pocket to move to a new place without risking dust or scratches on them. So they need to be removed between shooting locations, which can take the spontaneity out of shooting. Something that is integral to using a phone for photography.
That said, they work really well for their purpose, and the optics are very good indeed with no vignetting, internal reflections, or other nasties visible.
The wide angle lens gives a really nice view on things. There is some softening towards the edges, but this is minor compared with a lot of alternative models I have seen. Overall the image is pretty tack sharp. Allowances have to be made for this type of product because you will never obtain the same optical quality as a lens that is mounted and focussed directly in front of the sensor. With that in mind the performance of the Sandmarc 16mm is surprisingly good, and you won't be moaning that it has ruined a shot. Far from it.
There is some minor distortion towards the edges, but again, remember this is a very wide angle lens mounted in front of the phone's existing glass. Bearing that in mind, the distortion is pretty low, and I have seen far worse, and it is all easily correctable with post adjustment.
Some sample images
100% crops of the top and bottom left extreme edges.
The 16mm wide angle retails for US$99, which I think is actually pretty good value if you are an ardent smartphone photographer or video user. The Hybrid Filter set costs US$129 and comes with a clip mount for mounting if you don't have the company's dedicated phone case mount system, which comes with the lenses.
The wide angle lens and filters are compatible with all iPhones going back to version 7. Currently there are no options for other makes of phone.