Extended Exposures with the Singh-Ray Mor-Slo Neutral Density Filter

Share

Singh-Ray recently introduced their most substantial, long-exposure-inducing solid neutral density filter ever: the Mor-Slo ND 10-Stop Filter. This optically dense filter provides a highly effective reduction in exposure, allowing you to utilize larger apertures or longer shutter speeds for greater control over motion and selective focusing in bright conditions.

A neutral density filter’s objective is to provide optical density that is color-neutral. By increasing the opacity of a neutral substrate placed in front of the lens, you can increase the amount of exposure required to properly expose your film or image sensor. Neutral density (ND) filters are ideal tools to use when the conditions in which you are photographing are too bright or when you want to have more control of your exposure settings. ND filters let you use slower shutter speeds when photographing moving subjects, such as flowing water or traffic, in order to create a blurred effect.  Conversely, you can use ND filters to modify the aperture you’ve set in order to photograph with wider apertures and control depth of field. One of the most important values of an ND filter is that its effect and subsequent results cannot truly be replicated digitally.

While many other filters’ effects can be emulated during post production on a computer, the ability to alter the appearance of time passing or modify the depth of field cannot be duplicated nearly as well. This proves especially true when working with ND filters of such great density as the Mor-Slo ND 10-stop filter; its 3.0 optical density can convert traditional exposure times of 1/60 second into full 16-second exposures, allowing extensive amounts of time to pass during the exposure for controlled blur of moving subjects. This effect can render moving water as a smooth, soft blur or help to eliminate the sight of passing traffic on a busy street. By lengthening exposure times, the frozen nature of short-term exposures is eliminated and a sense of movement is more clearly depicted. Additionally, when photographing in bright daylight conditions where an aperture setting of f/22 might be required simply to expose the scene properly, this ND filter allows you to open up to your maximum aperture in order to highlight nearer subjects and place distracting backgrounds out of focus.

When working with a filter with such great density, typical shooting workflows may need to be adjusted because of the opacity of the filter. Since it is of such a strong density, it is difficult to view through the filter under normal circumstances, and it will likely need to be placed in front of the lens after composing and setting focus for the photograph. The most efficient means for using this filter requires determining a base exposure for the scene and then calculating the final exposure by adding +10 EV to your exposure measurement.

Auto-exposure systems will unlikely be able to determine a truly accurate exposure if metering through this filter, and as such it is more productive to simply add 10 stops of exposure by opening up your lens or increasing the shutter speed (or a combination of both). Here's an example: if a given scene of water flowing during daylight registers a meter reading of f/11 at 1/60 second, when the Mor-Slo filter is placed in front of the lens, you could then compensate for it by setting your exposure to f/11 at 16 seconds, which is 10 shutter-speed steps longer, in order to depict the water in a silky, flowing manner while keeping the stationary portions of the scene in sharp focus. It should also be noted that when working with this filter, a tripod is almost always a mandatory accessory, due to the longer shutter speeds.

One of the main concerns with neutral density filters of such great density is how they affect the overall coloration of an image during longer exposures. Since light is passing through the filter and reaching the shutter for such an extended period of time, any amount of tint or slight coloration in the filter will be magnified and visible in the final image. If a filter is slightly cool, the entire image could take on an intense blue coloring, and vice versa for a filter that is warm tinted. The Mor-Slo filter is designed to remain as optically neutral as possible, helping to ensure clean image files during the longest exposure times. This filter imparts a faint, warm amber color to the image that is easily manageable during post production, or even considered appealing for many subjects.

Also contributing to the overall image quality is this filter’s construction, which is a proprietary blend of highly polished glass that helps to realize high image clarity, contrast, and consistency. The square filters, which are available 84 x 84mm and 100 x 100mm sizes, measure 2.1mm-thick and fit the Cokin P and LEE Standard or Cokin Z-Pro filter holders, respectively. The Mor-Slo is also available in ring-mount sizes of either 77mm or 82mm; both are available in the standard 5.5mm-thick ring or the 4.6mm thin-mount design. The thin-mount design is ideally suited to working with wide-angle lenses, as it decreases the likelihood of vignetting with such lenses; however, thin-mount filters do not incorporate female threads on the front of the filter for attaching other filters to it. Both standard and thin mount ring filters feature anodized black aluminum rings and have the same highly polished optical glass filter substrate as the square filters.

Finally, there are two other types of the Mor-Slo filter, the Cokin Z-Pro-sized sprocket mount and the Cokin P sprocket mount. This design is a circular filter that has the same substrate construction as the other filters, but is housed within a 100mm diameter plastic sprocket in order to be used in conjunction with Cokin Z-Pro filter holders. The Z-Pro Holder design incorporates a small slot that is closer to the lens than the other filter slots, which enables the filter itself to be placed as close to the lens as possible while still retaining the ease of working with a filter holder. Since the filter sits closer to the lens than square filters, there is less likelihood of stray light affecting the image during such long exposures.

Each of these filter sizes can be used alternately to gain benefits that one or the other size doesn’t have: since such a dense filter requires composing without it in place, the square and sprocket-mount filters are ideal in this regard since they allow for easier insertion and removal of the filter. The circular screw-in type filters are a bit more time consuming to install and remove, but they are the most seamless in that they are closest to the lens. Additionally, an inherent benefit to working with neutral density filters is their compatibility with other filter types. Since the benefit of an ND filter is its effect on exposure value without modifying the coloration of an image, different color-compensating, graduated ND, polarizing, and effects filters can be paired with the Mor-Slo filter for added control over the resulting image. When paired with another filter, it is important to add the additional filter factor to the 10 stops of density provided by the Mor-Slo filter, too.

The Singh-Ray Mor-Slo ND 10-stop filter is a highly useful tool for many nature photographers as well as portrait photographers, astrophotographers, and a wide array of other creative photographers. The 10 stops of afforded exposure enable the creation of long exposures during daylight, providing the ability to showcase motion in a fluid manner. Since exposure times increase as a result of using this filter, there is also the need to slow yourself down when shooting, in order to preconceive the final look of image, and accurately plan on how to execute it. The added control over exposure times provides a wider range of freedom in the amount of movement and depth of field used in each shot, rather than exposing simply at the mercy of the given lighting conditions.

For more information on these Singh Ray filters, stop by the B&H SuperStore in New York, speak with a sales professional on the telephone at 1-800-606-6969 or contact us online via Live Chat.

  77mm Standard Ring Mount 77mm Thin Ring Mount 82mm Standard Ring Mount 82mm Thin Ring Mount 84 x 84mm Square 100 x 100mm Square Cokin Z-Pro Sprocket Mount
Filter Size 77mm 77mm 82mm 82mm 3.3 x 3.3" / 84 x 84mm 3.9 x 3.9" / 100 x 100mm 88mm (100mm sprocket)
Filter Thickness 0.22" / 5.5mm 0.18" / 4.6mm 0.22" / 5.5mm 0.18" / 4.6mm 0.08" / 2.1mm 0.08" / 2.1mm 0.2" / 5.2mm
Filter Holder Compatibility N/A N/A N/A N/A Cokin P Holder Cokin Z-Pro or LEE Standard Holder Cokin Z-Pro Holder
Optical Density 3.0
(10 stop)
3.0
(10 stop)
3.0
(10 stop)
3.0
(10 stop)
3.0
(10 stop)
3.0
(10 stop)
3.0
(10 stop)
Filter Substrate Polished optical glass Polished optical glass Polished optical glass Polished optical glass Polished optical glass Polished optical glass Polished optical glass
Filter Ring Construction Anodized alumium with front threads Anodized aluminum without front threads Anodized aluminum with front threads Anodized aluminum without front threads N/A N/A Plastic sprocket