Introduction
Accessory range finders are small optical devices that use the distance between two lenses to determine the distance to an object. To use one, you look through a viewing window. Inside you will two images superimposed over each other (one is tinted and only covers the center of window). Turning a dial on the range finder causes the two images to converge or diverge. Turn the dial until the the particular point that you want to measure is perfectly aligned. Then look at the dial itself: it will give you a reading. That’s the exact distance to your subject.
Rangefinder cameras have 
been manufactured for the past 100 years. Most models have a built-in range finder (hence their name). However, built-in range finders often only work for one lens or a set of lenses. Thus many manufacturers have manufactured accessory range finders that are essentially universal: instead of being coupled to a lens, they read out the distance, allowing them to be used with any lens. Their utility has ensured that many manufacturers have released range finders over a long period of time, and they are readily available on the used market. This range of choices, however, can be quite overwhelming. A few scattered reviews exist online, but we thought it would be useful to compile a comparison of many of the most common models.
Though at least one manufacturer still makes and sells an accessory rangefinder now, the rangefinder craze mostly spanned the 1930s to the early 1960s. Thus these are the golden decades for accessory range finders. Because the photography world was dominated by Germany and the US during that time, the vast majority of range finders out there come from one of these two countries. There are a couple of exceptions, however.
Most accessory range finders were designed to mount on cameras. Often this meant on a standard cold shoe. However, some range finders were designed with proprietary mounts for a particular camera, and some weren’t design to mount at all, but rather to be carried in a pouch or pocket and used as an independent device (camera mounting is only for convenience; the range finder works just as well independently of the camera, and is in fact less cumbersome). Mercury Works has developed several cold shoe mounts for popular range finders in order to adapt them. In addition, we have several generic cold shoe adapters that can be used on nearly any accessory, so it is possible to adapt nearly any range finder you wish to a Mercury or other contemporary camera.
We rate cost relatively, from $ (cheapest) to $$$$ (most expensive). Of course, relative cost is subject to change, and is dependent on availability and shipping costs to your region.
A word about length: In the specs for each finder, I’ve included a “length” category. Length is important for range finders, for these reasons:
The greater the distance between the two rangefinder measuring windows, the more accurate the meter will be, especially at farther distances. The length thus increases the effective range and precision of the finder.
On the other hand, longer range finders add more bulk and weight to your camera.
Longer range finders, especially if they have their cold shoe mount centered on their body, can interfere with other accessories on adjacent mount points, on a Mercury for example.
Thus length involves some tradeoffs. Just remember that the cute little rangefinder that fits so well on your camera is sacrificing range and precision for that compact design. Here’s an example of two models, optimized for different purposes, of Ideal’s range finders:
The top model can accurately measure distance out to 300 yards. The bottom can do so only out to 50 feet. But only the bottom one will mount nicely on your camera!
Without further ado, then, the roundup…
Saymon Brown / Lecia / Measure-Rite / De-Jur Range Finder
This is one of the earliest accessory range finders, made by Saymon Brown in New York, USA. This is a very high quality range finder, with great precision and accuracy. It is made entirely of metal, and includes threaded front window glass, easy access to internal elements, and multiple adjustment points.
This finder has a best-in-class measuring window distance, and hence the highest precision and longest usable range of any other accessory range finder I’ve tested. This is the result of excellent engineering, which maximized window distance while keeping the body rather svelte. It has a larger-than-normal distance dial to handle the increased precision, but unfortunately, that dial is crammed left of center, very near the eyepiece, making it uncomfortably close to your eye. Making matters worse, the original camera mount is located in between the eyepiece and the dial, on the far left of the finder! Luckily, when you replace this mount (see below), you can position it wherever you like.
The strange thing about this finder is that it appears to be nearly identical to Leica’s original accessory range finder. Perhaps Saymon Brown licensed the design from Leica; perhaps it is a clone. Regardless, the Leica version costs a couple of hundred dollars, while the Saymon Brown is under $30.
This also appears to be very similar in design to another American range finder, the “Measure-Rite Range Finder” by the Brownie Manufacturing Company. This retails for about the same price as the Saymon Brown. It uses the same machined components, but has a slightly different (and better) layout, and is gray/silver instead of black. The Measure-Rite, in turn, is almost identical to the “De Jur” by Amsco. The Saymon Brown, then, defines the typology of a large number of early range finders (like the Watameter in Germany; see below).
The greatest difficulty with the finder is its mount. It comes with a proprietary mount on the bottom, and discs on either end that fit in cold shoes from 1920s cameras such as the Leica A and I. The Leica variant (as well as the Measure-Rite) doesn’t seem to have the proprietary mount on the bottom, so the range finder was meant to mount to the Leica in a vertical position. The Saymon Brown and the De-Jur mounted to an unknown US camera model–probably a Brownie.
To mount on a modern cold shoe, you can either glue a Mercury accessory cold shoe foot to the bottom (model: “Tall Thin with Lip”) or thicken one of the round end-discs with either tape or a thin “washer” screwed in between the the disc and main body.
Country: USA
Known Units: Feet (Leica variant: Feet and Meters)
Length: long
Range: 2’6” to 300′
Mount: Proprietary mount (horizontal orientation), obsolete/loose cold shoe mount (vertical orientation)
Calibration: Two screws on top are likely for calibration, but their function is unknown.
Cost: $ (Leica variant: $$$$)
Image Visibility Score: 8
Special Features: All components threaded for easy disassembly.
Watameter
This is the Cadillac of accessory range finders! Art deco lines, a good viewfinder, a big knurled adjustment knob, extended macro range, internal readout, and one touch calibration make this the most full-featured range finder out there. All metal body with leatherette covering, you can spot this model’s elongated front windows from 50+ feet away, but you won’t know exactly how far, as this properly tops out at 50′ before hitting infinity.
Inside the bright viewfinder window, numbers appear on the lefthand part of the screen, indicated the currently selected distance. This way, you can instantly check the distance to your subject, or multiple distances in your field of view, without lowering the camera away from your eye. Fancy indeed! Less useful, but utterly unique in the world of rnage finders, is the short end. Why most rangefinders cannot register distance below around three feet, the Watamter Super can. Internally, the finder contains two scales. The first goes from 32” to infinity. If you continue to turn the dial after that point, however, another scale Picks up the numbers, starting at 30”, and goes down to 22”. After that, it jumps back to feet. While in this range, you must check the distance on your external dial, like other cameras. This dial ranges from 20” down to 12:”. This is certainly closer t
han any other range finder!
The eyepiece is made of aluminum and can be removed by unscrewing it. It can be replaced with an extended (but very rare) version.
Finally, the unit can be calibrated simply by turning the inner dial on the adjustment dial—this is about the easiest calibration ever designed. The potential downside, however, is that it could be turned by mistake or rubbed inside a camera bag. It is thus important to check this calibration more often than you would with a model that has hidden calibration controls.
The Watameter came in three main variants (sold concurently at different price points, not as consecutive upgrades as their titling would suggest):
Watameter I lacks the external macro dial and internal readout. Instead, it has a traditional external dial. It is still just as well made and stylish, but not distinctive with regard to features.
Watameter II added the internal readout.
Watameter Super added the external macro dial.
Perhaps confusingly, there were generational changes to all three models as well. Some had the adjustment dial with its knob, others had an inset adjustment that required a tool. Some had a second adjustment dial on the left side of the finder that adjusted vertical alignment. Others omitted this. Adding up all of these factors means that there are a huge number of Watameter variations, so make sure you know what you want and what you are getting. Still, all Watameters are built to the highest possible standards in the photo industry.
Country: Germany
Known Units: Feet and Meters
Length: compact
Range: 12” to 50′
Mount: Standard cold shoe (milled into body)
Calibration: Knob or screw in center of adjustment dial for distance, knob or screw for vertical alignment on left side of body (some models only).
Cost: $$$
Image Visibility Score: 8
Special Features: In-viewer readout, macro (some models), eyepiece replaceable with extended version.
Telex
The popular Telex appears to be almost identical to a Watameter II. It’s body is exactly the same shape, but is slightly thicker. It has the same large knurled dial and the same rectangular windows. It has a different faceplate (with the distinctively stylized “TELEX” logo and a different viewing window. It has an internal readout, but this is technically in a separate viewing window, right next to the first, and sharing the same eyepiece. In order to view the distance scale, you have to shift your eye slightly to the left; you cannot view both the distance scale and the superimposed image simultaneously. No macro function is available. These tend to be about as common as Watameters, and go for similar prices.
Country: Germany
Known Units: Feet and Meters
Length: compact
Range: 2.5′ to 35′
Mount: Standard cold shoe
Calibration: (mine does not include any obvious calibration screws)
Cost: $$$
Image Visibility Score: 8
Special Features: In-viewer readout (in side-by-side window)
Voigtlander
The king of rangefinder companies also made an accessory range finder. On the web it appears to have the highest reputation of any accessory range finder, but this is likely due only to brand association. Optically, it is good but not extraordinary. It possesses no special features or abilities. It’s just a well-made German range finder, but due to its brand recognition, it commands a high price on today’s used market. For the money, there are much better value
s out there. For top of the line gear, there are better models out there.
This range finder is unique in design in that the distance dial is located in the middle of the finder, with the cold shoe located toward the right side. Practically speaking, this cramps the distance dial against your viewing eye, a very questionable design. On the other hand, the short finder, combined with the right-oriented cold shoe, allows it to mount easily on even small Mercury cameras without interfering with adjacent cold shoes.
Country: Germany
Known Units: Meters, Feet
Length: ultra-compact
Range: 1m to 20m
Mount: Standard cold shoe
Calibration: Adjustment knob protruding from center of distance dial.
Cost: $$$$
Image Visibility Score: 8
Special Features: In-viewer readout (in side-by-side window)
ROWI
The ROWI is almost identical to the Voigtlander; one is clearly a copy of the other. Only the styling and small details are different.
Country: Germany?
Known Units: Feet
Length: ultra-compact
Range: 3′ – 60′
Mount: Standard cold shoe, removable (via screws)
Calibration: Adjustment knob protruding from center of distance dial.
Cost: $$$
Image Visibility Score: 8
Special Features: Replaceable eyepiece with extender option
BLIK
This Soviet range finder is a popular choice as it was produced in large quantities and is thus readily available and rather cheap on Ebay. It is large and bulky, and made out of utilitarian plastic, but has a certain modernistic/minimalist charm to its aesthetics. It has a cheap and badly sized cold shoe (with a screwed-on metal plate and a plastic column). Eschewing comfort, it has no eyepiece at all, but only a tiny rectangular inset window near the left corner of the unit. You will have to jam your eyeball into this corner, which in a rare act of mercy, is somewhat rounded.
Unlike nearly every other accessory range finder out there, this one has no perpendicular distance dial, but rather an internal, parallel dial that appears through a cutout in the unit. Functionally, it is difficult to turn (there is only a small knurled edge on it and since it only sticks out about 1mm, it’s slightly difficult to get good friction when turning it with a finger, and you can only turn it a small portion at a time). Again, this lack of protruding elements contributes to its modernistic aesthetics, but decreases its ease-of-use.
This one looks good on a Mercury, and its right-oriented cold shoe prevents it from interfering with other mounted accessories when mounted on the left. Its aesthetics also match the Mercury well. However, you have to be able to put up with its bulk and ease-of-use problems.
It’s optics are excellent, and its length make for high precision. It is available only in meters.
Country: Russia
Known Units: Meters
Length: long
Range: 1m to 15m
Mount: Standard cold shoe
Calibration: internal?
Cost: $$
Image Visibility Score: 9
Special Features: no protruding elements
Ideal Range Finder
Like the BLIK, the Ideal is made out of utilitarian black plastic and made well for a budget price point. It is the American version of the same finder, a warped Cold War mirror image. The Ideal is more traditional and functional in form, and less as ethically unique. It has a nice external dial with highly readable black-on-white lettering (one of the best dials in in all range finders covered here). The dial is capped off by a rather crude screw and (often rusty) hex nut. Like the Russian model, there are no fancy Germany flourishes here! It does have a unique square eyepiece that is generous in size and perfect for mounting accessories (like the Mercury laser attachment). Its front measuring windows feature clip-in plastic filters, which eliminates the problem of requiring a colored mirror. Colored mirrors can fade or rub off in time, making it impossible to see the superimposed images. This, as well as good engineering, make this a robust a long-lasting finder.
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This almost always exists in feet, but it is rarely available in meters. Because the dial face adheres to the plastic rather than being carved into it, it can be easily replaced. Mercury Works has both plates available.
The big limitation of this finder is its lack of a cold shoe. Mercury Works has a generic cold shoe that you can easily glue on to this one, in whatever position suits you best.
Country: USA
Known Units: Feet, meters
Length: medium
Range: 2.5′ – 100′
Mount: none
Calibration: Adjustment screw in middle of dial; hold hex nut with pliers and turn center screw to calibrate.
Cost: $
Image Visibility Score: 8
Special Features: Easy to change between feet and meters; square eyepiece for accessory mounting.
Hugo Meyer Pocket Range Finder
This was an early American accessory range finder with an oversized eyepiece and distance dial that are well spread out from each other, making it one of the most comfortable to use of all finders. Unfortunately, its long length does not translate into extra precision, as its measuring windows are not located at far ends of its body. Optically, it has better range and precision than a compact, but not as much as a standard long.
This finder, while not extremely common, tends to be cheaper (at lest in the USA) than any other used finder on the market. That makes it a great bargain!
It’s downside (which keeps the price low) is that it has a propriety mount. It will fit on a cold shoe, but not well. Mercury Works has a replacement cold shoe that screws on in place of the original, converting it to standard cold shoe.
Country: USA
Known Units: Feet
Length: long
Range: 2.5′ to 100′
Mount: non-standard cold shoe
Calibration: ?
Cost: $
Image Visibility Score: 8
Special Features: none
Walz
The Walz is an exemplary range finder that doesn’t offer much in the way of unique features, but gets everything right. Very well made of a combination of metal and plastic, it has great optics, a smart design that maximizes the distance between its measurement windows in a medium sized body, and a removable mount.
The removable mount press fits onto a post on the bottom of the unit (pictured here). Unfortunately, it is frequently lost. Mercury Works has a replacement cold shoe that press fits right onto the existing post.
The Walz has two generations. The first came in multiple colors, with a plain lettered logo on the viewer’s side and not much on the subject side. The later model comes only in black, and adds a red, raised Walz logo on the subject side, along with more uniquely styled measuring windows. This later model also added, on the right side cap (that threads on and covers the adjustment screw), a little circular chart that converts feet to meters.
The mounting post size is slightly narrower on the older version, and the Mercury Works replacement cold shoe fits a bit loosely (but you can add a tiny bit of tape to fix that).
Overall, a fabulous range finder.
Country: Japan
Known Units: Feet
Length: medium
Range: 3′ – 60′
Mount: Standard cold shoe
Calibration: none visible
Cost: $$
Image Visibility Score: 8
Special Features: none
Prazisa
The Prazisa was and is popular in Europe, and is readily available. It is in the ultra-compact category, with reduced precision and range, but with cute styling and practical mount options.
Country: Germany
Known Units: Feet, Meters
Length: ultra-compact
Range: 2′ – 40′
Mount: Standard cold shoe
Calibration: none visible
Cost: $$
Image Visibility Score: 8
Special Features: none
Widor
Widor is another excellent ultra-compact range finder. Like others in this category, it has reduced range and precision, but compensates by adding some very close distances (2′).
Country: Germany
Known Units: Feet, Meters
Length: ultra-compact
Range: 2′ – 35′
Mount: Standard cold shoe
Calibration: ?
Cost: $$$
Image Visibility Score: 7
Special Features: none
Photopia
Yet another excellent ultra-compact range finder. Though like most, this is made in Germany, it seems to be most popular in the UK… Unlike most others, it has a Watameter style large calibration knob. It also has a rather large overlap area, for excellent usability. This is probably the best of the ultra-compacts.
Country: Germany
Known Units: Feet, Meters
Length: ultra-compact
Range: 3′ – 40′
Mount: Standard cold shoe
Calibration: none visible
Cost: $$
Image Visibility Score: 9
Special Features: large/easy calibration knob
Riwex
Yet another ultra-compact range finder. This is the smallest of them all, though it has a generiously thick distance dial that sticks out a ways on the right side. This is on the extreme side of compact!
Country: Germany
Known Units: Feet
Length: ultra-compact
Range: 3.25′ – 60′
Mount: Standard cold shoe
Calibration: center screw in dial
Cost: $$
Image Visibility Score: 8
Special Features: none
Kodak
Though only manufactured early on (probably in the 1930s), the Kodak range finder is top flight. This is unlike all other range finders I’ve seen. First of all, it was meant to mount to a Kodak camera (I’m not sure which one) via a strange circular locking mount, sticking straight out of the camera. Secondly, its distance dial is located on the front, or measuring, side of the finder, not the viewer side! The only feature on the viewer side is the eyepiece itself.
Fourth, this finder features a split image screen instead of the usual superimposed image screen. Which works better for you is a matter of preference, but the split image finder gives a larger and brighter image with which to focus.
The single viewfinder on this unit displays, side by side, the split image and an internal distance readout. So one can view the set distance from either in the viewfinder itself or on the front side of the unit/camera, an ability no other range finder has. Personally, I happen to also love the aesthetics of this art-deco era device with its clean lines, circular chrome highlights, and fantastic beige color. To mount it on a modern camera, you’ll need to replace the metal plate on the right side (which serves no purpose other than enclosing the mechanism) with a drop-in replacement cold shoe end from Mercury Works. The range finder will still mount straight out from the top of the cold shoe!
Country: USA
Known Units: Feet
Length: medium
Range: 2′ – 50′
Mount: proprietary
Calibration: none visible
Cost: $$$
Image Visibility Score: 10
Special Features: internal readout, dual readout (on both sides), mounted from end rather than bottom, split image screen.
Colon
(pictured at top of page, in front)
Despite its unappetizing name, this Japanese range finder is very unique as the most compact in total dimensions unit available. It is svelte on each side, but its secret weapon is a cold shoe mount divided into two sides, each of which folds up into the bottom side of the finder! Ultra compact when on a camera, and ultra-ultra-compact when stored off a camera. Perhaps the ultimate travel range finder for tight spaces. It has great styling as well. The downside is of course its reduced precision and range.
Country: Japan
Known Units: Feet
Length: ultra-compact
Range: 3′ – 50′
Mount: Standard cold shoe
Calibration: knob in center of distance dial
Cost: $$$
Image Visibility Score: 7
Special Features: tiny; fold-away cold shoe mount