Hitech Pro Stop 10 ND Filter

This is a quick review of the Hitech Pro Stop 10 ND Filter, designed to dramatically decrease the amount of light that enters a camera lens. Why and when would one need such a filter? With less light passing through the lens and reaching the film or digital sensor, slower shutter speeds/longer exposures have to be used, which ultimately blur any kind of motion. This neutral density filter is specifically designed for landscape photography: for photographing waterfalls, flowing rivers, moving clouds and other type of motion.

One of the biggest issues with photographing motion is controlling the shutter speed. People often ask me how I get that “dreamy” look in my waterfall photographs. The answer is quite simple – all I have to do is slow down the shutter speed, which makes the falling water appear blurred. While there are some ways to decrease the shutter speed by setting ISO to the smallest number such as 100 and decreasing the aperture (or increasing the f number), it can be problematic for two reasons: the scene is often too bright, and image quality can be severely degraded when aperture is too small (diffraction). That’s when Neutral Density filters come to the rescue – they absorb most of the light and only let some of the light through.

1) Product Information

Product Specifications:

1. Type: Solid neutral density
2. Size: 6 x 6″ / 152.4 x 152.4mm
3. Filter Factor: 3.0 (10 stops)
4. Effect: Permits an increased exposure
5. Construction: CR-39 dyed resin

Main Features:

1. This filter measures 6 x 6″ / 152.4 x 152.4mm and is constructed from specially dyed CR-39 resin.
2. 3.0 ND filter darkens the image, allowing you to photograph with a longer shutter speed or wider aperture than normally required.
3. Providing a reduction of 10 stops, this filter allows you to control depth of field and convey movement more easily.
4. Foam gasket around the perimeter of the filter helps to reduce flare and provides additional reinforcement.

The Hitech 6 x 6″ Pro Stop 10 3.0 ND Filter is a solid neutral density filter providing an exposure reduction of about 10 stops. This 3.0 density creates a darkening of the entire image, allowing you to photograph with a wider aperture or slower shutter speed than normally required. By slowing your exposure time or increasing your aperture, you are able to control depth of field and convey movement more easily. This filter also integrates a foam gasket around the perimeter of the filter to help reduce flare and non-direct light from reaching the lens. This gasket also helps to reinforce the filter substrate and offers more protection from accidental drops.

2) Packaging and Use

As shown in the first photo, the filter comes in a soft black leather-like pouch. The filter is wrapped in paper, which I threw away after unwrapping the filter. A small Prostop User Guide is included, which has some useful information about the filter and how it should be used. The first page of the guide talks about Color Cast:

The filter has been purposely designed to give a slight blue color cast to assist in enhancing landscape shots, particularly in relation to water and skies. This can easily be removed using Photoshop or other software programs. Each filter is made to stringent standards but batch variation does occur and this may sometimes give more of a green-blue cast dependent on the conditions in which the filter is used.

Next, under the “Set Up” section, it says that RAW is generally recommended over JPEG. Then, it says that white balance should be manually set, which kind of contradicts the “shoot RAW” statement. If you shoot RAW, white balance simply does not matter – you can set it to whatever you want in Lightroom/Photoshop.

When I first mounted the filter on my camera, I was confused by what I was seeing. My white balance (which is typically set to “Auto” since I shoot RAW) was indeed screwed up, giving me all sorts of strange colors in the scene. Blues did not look like blues and greens were too light/bright. I took the filter out and everything went back to normal. Then, I found the little booklet and read the above info. I was quite disappointed by this “feature” to be honest, since the color cast does absolutely nothing for people that shoot RAW. That’s why I don’t buy color/warming/cooling filters of any kind – those are only good for film and JPEG shooters. While the blue color cast won’t damage images, since I can easily fix them in Lightroom/Photoshop, I just do not want to deal with setting white balance on my camera to be able to view the image correctly on the LCD. The Nikon D800E could not cope with the blue color cast, so I do not expect any camera to guess the white balance correctly. So for me personally, this blue color cast feature is simply worthless. On top of that, my filter sample was definitely affected by both green and blue color cast, as warned in the user guide.

Lastly, there is a “Gasket” section, which talks about the gasket that is attached to the filter and its role in preventing light leakage.

The very last page of the guide contains the following Exposure Chart:

10 Stops is a huge exposure change, as evidenced from the above table. This filter takes 1/250th of a second down to 4 seconds, which is quite impressive. Because of this, the filter is so dark, that it almost looks completely black:

Dark is good for increasing exposure time, but it is not good for your camera’s autofocus system – forget about AF operation when using this filter. The best way is to take the filter off, acquire focus, switch to manual focus and only then slide the filter into place. If you do not change to manual focus, your lens will hunt back and forth even in broad daylight.

3) Sample Images

4) Summary

I have used ND filters quite a bit in the past and I have been very happy with my circular B+W 77mm 1.8 ND MRC filter (6 stops), which has been by far my most favorite ND filter for slowing down exposure time. While it is not as dark as the Hitech Pro Stop and not as versatile as the Singh-Ray Vari-ND, autofocus on the D800 typically works with it, there is no need to mount a filter holder and it does not cause vignetting issues. If I needed to get something darker, I would go with a darker B+W circular filter instead. Overall, I am quite disappointed by this filter, especially by its green/blue color cast. There are plenty of other good circular clear ND filters out there that have much better performance and value in my opinion.