My photographic journey over the last few years has often turned me towards nature, from vast sweeping landscapes to the tiniest details my ageing eyes no longer see on their own. And once one starts to capture the macro world – or is that the micro world? – I find there is an irrepressible urge at times to get closer and closer with magnifications beyond the 1:1 true macro threshold.
If close-up shots of larger objects such as flowers didn’t convince you yet, capturing small critters or objects at higher magnification really make it dawn on you that the depth of field achievable in a single shot is extremely shallow. And that is almost regardless of the aperture used. Additionally, even a minuscule movement of the camera due to breathing can completely change your composition and focus point. Enter a macro rail (and some focus stacking capable software) to solve both issues.
NISI Australia kindly agreed to lend me their NM-180 macro rail for a couple of weeks, a newcomer to their gear lineup, and as far as I am aware, Nisi’s first and only foray into this type of equipment.
The price range and quality of macro rails available in today’s market varies considerably from cheap eBay sub $30 clunkers to highly refined and pricey motorised and automated machines capable of nanometric adjustments suited to the magnifications produced by strong microscopes. The Nisi rail fills a niche of quality equipment in the lower to mid-range segment of this market.
Having tried some of the cheap rails and even one of the other sub $200 articles, I could not fail to be impressed by the NM-180 in all respects. Unboxing the rail was a pleasure as it comes nicely packaged with a protective pouch and Arca-Type quick release plate. The quality and polished looks of the rail itself with its all metal CNC machining, nicely curved looks, almost pocketable size and relatively light weight all make it shine straight out of the box.
As its name suggests, the NM-180 measures 18cm front to back but has a 16cm stage, which is ample for most jobs you may want to throw at it. This is primarily a two-way macro rail, meaning that it travels back and forth and just a little side to side. There is however a ruler engraved on the Arca-Type clamp (as well as on both sides of the stage), which also swivels 360 degrees, allowing a good level of flexibility in positioning. To have full additional axis movement, two rails can be stacked together. But to be honest, I never found a worthwhile use for the horizontal shift and find that the minimal implementation of another axis enhances stability, portability and weight.
Taking a closer look reveals that contrary to other rails I have used, the whole rail functions as an arca-type extension directly compatible with most tripods. Tripods can also be connected directly through the standard 3/8” and ¼” screw holes. Another difference with the bulk of rails out there is that the Nisi comes with four rubberised and adjustable feet. This makes use of the rail on your desk so much more convenient than on a tripod. And let’s face it, it’s much easier to set up a stack of many images in the comfort of the controlled studio or home environment than it is in the field.
But the true measure of the rail value is in the details and the precision of its use. The most obvious difference with el cheapo models is the most critical – its stability and precision. If you check out the tightness of the NM-180 screw thread and the play in the mechanism that moves the camera back and forth, it is really a far cry from lesser models. I found the stability of the rail was really solid on a desktop on a surface like timber, where the rubberised feet get a nice grip. There is no perceptible play or backlash when the mechanism is made to move back or forth with either the retractable little ‘crank’ knob or the back precision thumb-screw. The crank allows to fairly precisely gauge the incremental focal distance of each shot to be included in the stack. Another nice touch that helps is that it has a little pin to indicate the exact position on the marker.
In the sample of the beetle here I took a first shot of the bugs nearest focal point then proceeded to give the crank a full revolution to the next shot (one full revolution advances the camera 1.25mm) and ended up taking 15 images until the focus was on the furthest part of the bug. Stacking these images in Photoshop or like here with Helicon Focus will give you sharpness front to back. Depending on the magnification and aperture you may want to take shots at say each quarter or half revolution just as easily. In the following images of the figurine I took 25 shots approximately half a revolution (about 0.65mm) apart to cover a similar focal range of around 2cm.
What’s not to like? Nothing much really, particularly at this price point ($199 RRP and less in the current Nisi sales see https://nisifilters.com.au/product/nisi-macro-focusing-rail-nm-180-with-360-degree-rotating-clamp/). If I were to be really picky, I would say it would be nice to have some cover over the main adjustment screw as it is quite greasy and perhaps add a bubble level.
Nisi sells the rail either on its own or in combination with one of their close-up lenses which come in both 58mm and 77mm threads, other great additions to the macro photographer tool bag and the subject of a future blog.