URTH Variable ND2-400 Review

In this test I’ve looked at the 77mm ND2-400 variable ND, that’s 1-8.66 stops of exposure reduction, which is quite a range for this type of filter.

It’s more common for manufacturers to split the ND coverage between two separate filters; 2 to 5 and then 6 to 9 stop. Putting this range into one filter is certainly unconventional, but ultimately more convenient. However, my first thoughts are how will this range affect quality, can this range really be done? Of course, there’s only one way to find out and that’s to give it a go.

GOBE now URTH have been producing filters for many years so despite the company name change they have a long history of producing quality gear.

From the recycled cardboard packaging to the metal filter case, the company’s relaunch branding gives the impression that URTH is trying to position itself a level up from GOBE.

The new filter does feel like a step-up from most budget filters with quality machining that gives the circular rotation of the front element a precise and smooth feel.

Looking over the variable ND and the addition of annotation around the edge of the filter, highlighting the density values is a welcome touch, as is the textured bevel and end stops.

The URTH Variable ND may be at the mid-range price point, but the company has gone the extra distance to ensure that this variable ND is relevant and appealing in a crowded market.

Arriving in a tough metal case, the UTHR VND has an instant premium feel.

It has the usual dual polariser design and screws directly into the lens’s front, like all other circular filters. A nice touch is a threaded front which enables you to stack additional filters on top, if you feel the need.

Getting started and adjusting the filter to its minimum intensity the 1-stop impact is mild, extending the exposure from 1/125 to 1/80 about 2/3rds of a stop.

Checking over the frame and there’s no sign of vignetting around the edges, and the image looks clean and crisp.

Firing off a few shots and the cameras AF system locks on and focuses as required.

However, start to rotate the front element, and the Neutral Density filter’s effect kicks in. While some filters require a fair degree of rotation to adjust the exposure reduction effect the UTHR is straight in there.

No doubt the need for only a slight rotation is due to the large density reduction range. As the front element rotates and the density increases focusing starts to become tricky, so it’s best to lock on focus, switch to manual, and then dial in the density.

The filter offers an impressive range and gives you plenty of scope to experiment in the field.

Setting the camera on a tripod and taking a shot shows the magnitude of the exposure difference between the minimum and maximum density.

Setting the filter to a minimum, ISO to 100 and aperture to f/8 resulted in an exposure time of 1/250. Set the filter to it’s maximum and the exposure time extends to 1/2 sec, so a 7 stop difference.

I tested this in a few situations, and the values varied depending on the amount of light available but seemed to close enough to the values stated by URTH.

Checking through the images back in the studio and the results were good. Colour and tone were well represented, and the filter’s use hadn’t affected the images’ quality too much.

The inclusion of the end stops also helps to prevent the dreaded X which can appear if the VND effect is overbaked.

Several things were noticeable, firstly the lack of a colour cast. The coatings on the filter seemed to do a great job, and while there may have been a slight blue cast, this wasn’t too noticeable and is, of course, easy to correct.

The vignette can be another factor that commonly affects variable NDs, and again this is well controlled by the filter, and it’s slim profile.

In use, the filter works well, and the 77mm version feel like a good quality filter that would work perfectly for both photography and video.