Light Craft Workshop ND500 MC Filter Review

Features
Handling
Performance
Verdict
Specification
More on long exposure photography

Click on the thumbnail to view a high resolution image

The Light Craft Worksop ND500 MC sells for £64.99 and is currently only available in the 77mm screw thread fitting. More sizes are due shortly.

We produced this review at the same time as another Light Craft Workshop product, the Fader ND MkII. Click here to read that review. Read my verdict on the LCW Fader ND MkII and you will know that I think it is good value on the proviso that you shoot a range of subject matter where you might want varying degrees of light loss and prefer telephoto lenses. Without wishing to give too much away, and by implication, the fixed value ND500 MC sounds perfect if you shoot with any lens and prefer scenics where a nine-stop light loss comes in very handy. So, is it?

Light Craft Workshop ND500: Features
This is a fixed density light absorbing filter taking out around nine stops of light, so handling is much more straightforward than the Fader ND MkII, ie you just screw the filter in and away you go. This slim filter will probably fit the widest wide-angle without causing any serious vignetting. You can see from the images below how thin this filter is.

Light Craft Workshop ND500 MC: Handling
Of course functions such as composition and focusing should be done before the filter is attached because the ND is fixed at nine stops, and then care taken when fitting it to avoid moving the focusing barrel by mistake. I thought that adding the filter itself would cause a little focus shift, ie the sharp image would become slightly out of focus, but I did not really notice any.

Click on the thumbnails to view high resolution images
The LCW ND500 MC has a thin mount so there should be no problem with using very wide-angle lenses.	The ND500 MC (the lower filter in the above image) compared with the ND Fader Mk II, which is much thicker.

Light Craft Workshop ND500 MC: Performance
Yes, it works – and very well too. I just metered as normal, then did the arithmetic to work out the required exposure. This is not that difficult once you have done it a few times. Being a simple soul,  I just counted out shutter times on my fingers doubling each time until I got to the ninth digit. It would not take a much effort to make yourself a handy reference chart.

When the light levels were low I had to use the camera’s B (bulb) setting - my camera has 30secs as its limit in autoexposure mode. I used the Nikon MC 36 remote control which has an integral stop watch among other features to time my shots.

If the exposure was relatively short, ie within the 30secs, I left the camera to expose automatically, which worked fine.

The filter is not true neutral density and it gives a slight cooling effect when AWB is used. Using shade or cloudy white-balance helps but setting a higher Kelvin value, say to 6-7000K is another option. I always shoot Raw so I left the correction until I was sitting in front of the computer.

One technique point to remember with this form of photography is to use the eyepiece blind if your camera has one. Or use a sheet of card hanging down from the camera hot-shoe or just drape a piece of dark material over the eyepiece. You could even shield the eyepiece with your hand although this is not fun for an eight minute exposure. Light entering the viewfinder eyepiece can cause internal reflections and ghosting can record on the image - there is an example of this below. It is easy to forget to do this and that can be very frustrating and a waste of time.

By the way, you will notice that on the images below that there is debris on the sensor - I normally clean up images but I wanted to show you the issue. Use a small lens aperture and you get lots of depth-of-focus (this is focus behind the lens) and any debris sitting on the sensor will record. A perfectly clean sensor is ideal but it is not reality so expect to do some cloning in Photoshop afterwards.

Click on the thumbnails to view high resolution images
This is the filter-free image, exposed at 0.6sec at f/22.	Taken at an exposure of 180sec, about 8.5 stops down on the original exposure.
The viewfinder eyepiece needs to be covered (with the built-in blind or your hand) to avoid any internal reflection problems.	Shoot anything plain with the lens set to a small aperture value and you are going to see every bit of muck on your sensor.

Light Craft Workshop ND500 MC: Verdict
Yes, certainly very happy to recommend this filter for long exposure work and great value too. The 77mm fit costs £64.99 so it is cheaper than the B+W ten-stop ND filter (£75) and the Lee Filters Big Stopper (£80), although it is true that both these rivals are ten stop ND filters. Assuming you are happy with nine-stops light loss, the Light Craft one is excellent and it works fine.

"Light Craft Workshop neutral density filters are great value for photographers wanting to explore very long exposures and they are great value for money."

Light Craft Worksop ND500 MC: Pros
Opens up lots of creative opportunities
Thin mount suits wide-angle use
High optical quality

Light Craft Worksop ND500 MC: Cons
Slightly cool colour rendition is a very minor niggle

FEATURES
HANDLING
PERFORMANCE
VALUE
OVERALL

Light Craft Workshop ND500 MC: Specification

Price:	£64.99 for 77mm fit
Contact:	www.premier-ink.co.uk
	www.lightcraftworkshop.co.uk
Sizes available:	77mm, more fittings to be available soon
Weight:	32g (for 77mm fitting)

 For more details or to order a Light Craft Workshop ND500 MC, please click here

More on long exposure photography
With film, making an exposure greater than one second with a normal colour slide film meant a colour shift and a loss of effective film speed – this was referred to as reciprocity law failure.

In practice, this meant that you had to think more about your exposures when shooting longer than one second with film. Let's say you were photographing a night scene and you determined the exposure to be 1sec at f/8. If you now decide that you wanted to use an aperture of f/16 this would mean that to get the same image density you have to increase the shutter speed to give two more stops of light to allow for the smaller aperture – in theory. As you know, aperture and shutter speeds have a reciprocal relationship so, in theory, one stop over 1sec is 2secs and two stops over is 4secs, so for an aperture of f/16 you need an exposure time of 4secs. Easy.

However, with film, there is a breakdown in the cosy reciprocal relationship between aperture and shutter speeds. In practice, 4secs at f/16 would give an underexposed result and to give the correct image density the exposure would have to be 8secs at f/16 or even 16sec at f/16. The speed loss characteristics of individual films varied greatly but the longer the exposure the greater the effective speed loss.

Sorry about preamble but it helps to understand why very long exposures with film was painful yet with digital it is the proverbial piece of cake. In our example above, make digital exposures of 1sec at f/8, 2secs at f/11, 4secs at f/16, 8secs at f/22, 16secs at f/32 and 32secs at f/45 and you get exactly the same image density. There is no speed loss, and that is why long exposure photography with digital is easy. Of course, there are still issues to sort, but reciprocity law failure is not one of them.

This theory stuff is all well and good, but you are probably wondering what are the advantages of shooting such stupidly long exposures and what have Light Craft Workshop, Lee Filters and B+W neutral density filters got to do with it.

Long exposures means you can take pictures by moonlight and in other similar extreme low light situations. But long exposures is also a way of being creative and suits all sorts of photographic subjects. For example, a four minute exposure of a busy shopping centre would result in everyone that moved within the scene during the exposure 'disappearing' or looking ghostly. Everyone who stayed still during the exposure – and obviously the buildings – would come out solid. The effect can be awesome.

The thing is, though, that setting a four minute (or however long) exposure and getting correctly exposed images is not as easy as it might seem.

You stand a chance when light levels are very low, ie in poor light, at dusk, night, but in anything like decent light, even setting the lowest ISO and the smallest aperture your lens can offer might not be enough to get you down to longer than 1sec at f/22. In other words, the exposure is nowhere long enough to blur the scene. Our shoppers in the example above would just be a little blurred but still plainly in evidence.

Using slow shutter speeds in bright light is one technique that you can enjoy with these light absorbing filters, the other is being able to set very wide lens apertures for shallow depth-of-field in similar lighting conditions. In bright light you might be at the lowest ISO setting your DSLR offers but an aperture of f/2.8 might require a shutter speed of 1/8000sec or more, which be beyond the camera's range. Fit a strong neutral density filter and again you stand a chance. Having a variable neutral density gives even more flexibility.