The rapid evolution of Leica DISTOs over the last 20+ years has been driven by the the way DISTOs improve work flow by increasing the ease, efficiency, and accuracy of measurement tasks.
The first laser distance measurer (also the first DISTO) measured distance and could calculate simple area or volume. 20 years later, that is still all the functionality some users need. That's why we still sell the D2, E7300x, and the E7100i -- they all have much better range and additional capabilities than a first-gen DISTO, are a fraction of the size, are inexpensive, and make it easy to use the basic functions of a DISTO.
As our technology evolved so did our ability to introduce new functions that addressed increasingly complex measuring tasks. These functions are geared towards design professionals. Some of them are rather specific (ie. Sloped Object Measurement) while others have broad appeal -- like the ability to share measurements in real time using Bluetooth.
Everything mentioned below is the result of 20+ years of experience building laser distance measurers (LDMs) and watching their use in the hands of professionals. Whether these are "Nice to Have" or "Must Have" really depends on what you do:
IP65 Protection Rating - If you are working in dirty, wet or demanding environments, go for an IP65 rating or higher. Dropped your LDM in the mud? No problem, wash it off with a hose. Many of the IP65 products are also rated for 3-6’ drop resistance as well.
The most rugged IP65 DISTO we currently sell is the E7400x (the video below shows the E7400x hitting targets the rain).
Built-in Tilt Sensor – A solid-state Tilt Sensor adds the degree of inclination or declination to the mix and provides a value that adds a lot to the usefulness of a DISTO.
For example, if you know the distance and vertical angle to an object you can measure the height of the object, the slope up or down, and the actual horizontal distance to that object.
Imagine trying to measure a room filled with furniture, people, or both -- a common scenario for designers who need to get as-built measurements in active commercial spaces. The “Smart Horizontal” function uses the tilt sensor to determine the actual horizontal distance to a wall from where you are standing even if you have to shoot several feet up the wall to avoid hitting anything.
There's no need to wait for the place to clear out, or move stuff around to get a shooting lane, or to hold the DISTO perfectly level – just measure above the obstacles on a slope across the room and the DISTO will display the slope distance, the horizontal distance and even the height distance between your starting point and end point.
Another neat trick: Depending on the working range of the sensor (normally +/-45° up to 360°) you can also use your DISTO as a digital level. Use it to check the slope of a ramp for ADA compliance or find out if a door jamb is plumb. Working accuracy is normally +/- 0.1°.
Digital Viewer - Read LDM reviews or posts on user forums and you’ll find the comment, “I love my laser distance meter but I can’t see the laser spot outside”.
One of the first solutions we tried (years ago) was an optical view finder -- like the one pictured here that we made in the mid-90's -- to a range-finder type lens with a cross hair etched into it like the old Kodak Instamatic cameras had and that some of our competitors still use.
At Leica Geosystems, we've moved on to using a digital point finder that is based on the digital zoom technology you find in a decent camera. If you need to measure outdoors a lot this is a must have piece of kit.
Point finder-equipped DISTOs have 1 or 2 camera lenses built in to provide up to 4x zoom. The crosshair displayed on the display identifies EXACTLY where you are measuring, even at the limit of the device's range. This feature will save you serious time and frustration – and is the only real solution for outside visibility.
The D810 Touch takes it a step further and can store a picture of the measure point, with the crosshairs and the measured distance both overlaid on the image, that you can access later. In addition to making it really easy to recall which measurements go with what, photo documentation is a requirement for Building Information Modeling (BIM).
Bluetooth– There is an expanding crop of new mobile apps that take advantage of a Bluetooth-equipped DISTO's connection to a smartphone or tablet.
When measurements are captured in real time, the across-the-board benefit is the elimination of human error. After that, it depends on the app. There are apps that enable you to update BIM models in the field and that enable you to upload plans to the cloud that you can import into your desktop software once you get back to the office.
Most modern phones and tablets are equipped with Bluetooth SMART, which is easier to sync-up and uses less battery power than earlier Bluetooth versions. With the recent introduction of the E7100i, you can get a Bluetooth Smart interface for under $150. Bluetooth isn't a necessity for everyone, however, even if you don’t need it now, sooner or later, you're going to want it.
Sunlight visible color graphic display – Thanks to smartphones, we are all familiar with the advances in display technology over the last few years. Graphic user interfaces (GUIs) have enabled us to make accessing functions and displaying measurements much more intuitive.
Power options– The flip side of color GUIs is that they draw more power than the older LCD tech, so we upgraded our battery offering. AA or AAA batteries are giving way to the same Lithium Ion tech that powers smartphones, laptops, and Teslas. In some cases, we use the rechargeable AA Lith-Ion form factor to retain convenience of dropping in some fresh AAs in the field.
So those are the features we've added over the years that are really "nice to have" depending on what you do. In my last "What to Buy" post, I'll focus on the latest, coolest tech we have introduced to LDMs.