Suunto Observer TT Wrist-Top Computer Watch with Altimeter, Barometer, and Compass (Titanium)

From the reviews, it appears that many users are confused by the clasp, claiming it doesn't allow enough clearance to get the watch on and off. This confused me also, and Suunto should come out with a new edition of the instruction manual that makes it clearer that the band has two clasps and when both of them are open, there is plenty of clearance getting the watch on and off.

Don't believe any reviewer that says the altimeter in this watch isn't accurate. If it isn't accurate, return it, because it means the watch is defective. A working Observer will be as accurate as the most expensive Thommen precision analog altimeter. I know, because I've owned the same, reliable Thommen (showing 20-foot intervals) for 29 years and have A-B'd the Observer with my Thommen on several hikes and have obtained as similar results as can be expected, given the intrinsic nature of altimeters based on the measurement of air pressure.

Although the manual can be criticized for its organization and sketchy documentation of its sometimes bewildering variety of features, it does give a fairly clear explanation of why altimeters in general can be as much as several hundred feet off over an elevation gain of several thousand feet, in spite of the fact that the sea level barometric pressure remains constant. Section 3.6 of the manual explains the effect of air temperature on altitude measurement. As the temperature rises, the air gets lighter, i.e. the barometric pressure falls. This is an intrinsic problem associated with any altimeter that works off of barometric pressure, including the world-renowned Thommen altimeters. Thus every altimeter must be calibrated to a set of certain "standard" temperatures. As long as the outside temperature tracks this standard and the sea level barometric pressure doesn't change, the altimeter will give an accurate reading. But the reading could be hundreds of feet off after a long hike in extreme temperatures.

The Observer instruction manual presents a table defining Suunto's standard. You can use this table to calculate the actual altitude, given the starting altitude, starting temperature, temperature at the destination, and the watch's altimeter reading. At first I found the calculation hard to understand, and Suunto's table presents lower and lower resolution as you increase in altitude, ostensibly (but not really) making the table less and less useful as the altitude increases. Eventually however, I "cracked the code" and wrote a program for the PC that calculates the correct offsets and even creates tables for all the variables. If interested, contact me via email for a free copy of the program.

Here are some examples. If you climb in temperatures that are much hotter than the temperature compensation standard built into the Observer, you will find that the readings from the watch will be several hundred feet lower than your actual altitude. For example, if the starting elevation is 100 feet and the starting temperature is 90 degrees F. and you climb until the Observer altitude reading is 4,000 feet and the temperature is still 90 degrees, your actual altitude will be 4,329 feet. On the other hand, if you climb in temperatures that are much colder than the temperature compensation standard built into the Observer, you will find that the readings from the watch will be several hundred feet higher than your actual altitude. For example, if the starting elevation is 100 feet and the starting temperature is 0 degrees F. and you climb until the Observer altitude reading is 4,000 feet and the temperature is still 0 degrees, your actual altitude will only be 3,685 feet. Finally, if you climb in temperatures close to the compensation standard built into the Observer, you will find that the watch display will be very close to the actual altitude. For example, if the starting elevation is 100 feet and the starting temperature is 58 degrees F and you climb until the Observer altitude reading is 4,000 feet and the temperature has fallen to 45 degrees, your actual altitude will be 3,998 feet. The reading is very close to the actual altitude because the temperatures at the start and end of the climb are very close to the built-in standard, which you can check out by looking at the table in sec. 3.6. (By the way, the manual has a math error in the example it gives for "Imperial" measurements. The difference between 47.3 degrees F and 36.3 degrees F is 11 degrees, not 9 as stated in the manual. Thus the actual altitude should be 9,724 feet, not 9,740 as stated in the manual.)


Good watch with a few gotchas   August 20, 2002
 5 out of 5 found this review helpful

I bought the stainless steel version of the Observer. Things you should know:
1. It is hard to buy this watch significantly discounted and still get the USA warrantee -- Sunnto tries to keep sales at list price.
2. This watch is not shock resistant, despite what I had seen elsewhere on the Internet
3. The watch band seems to not open up much. If you have a small wrist but large hand, you may have trouble getting this watch on and off. However, more careful examination reveals that the watch band opens up in two places, which makes the watch band's double-button lock less secure.
4. The stainless band is phony -- it's really a rubber band with a several embedded metal "ornaments" on each side made to look like a metal band. The part of the band under my wrist has no such ornaments and is all black. The stainless model still probably looks better than the black band. But if the titanium uses the same gimic with metal ornaments, buy the stainless which would be a better value.
5. For some reason, the watch shows a funny R in the FR weekday display on Fridays -- live with it!
6. Because of the barometer, the watch has a thermometer function, although it might only be accurate with the watch off wrist.
7. There are calibration functions for the compass and, I think, barometer. I haven't had a chance to check to see how accurate these instruments really are.

The Casio barometer/altimeter watch is a better value than the Sunnto although it is nowhere near as elegant as the Observer. And a regular ol' G-Shock will trounce the Observer when it comes to durability and battery life.


A Great Watch For The Outdoor Person.   May 25, 2002
 4 out of 4 found this review helpful

Great conversational piece. The Titatium housing gives it a cool look on the black face. As for the performance, I have found the Barometer & Compass to be extremely accurate. The temperature is very accurate, but you have to take it off your wrist for true reading. I also love the chronometer stopwatch for jogging, timing each mile. I have not gone skiing yet so I really did not use the altimeter or try to figure it out yet. The only negative I found is the alarm is not that loud and for the price I think the band could be all titatium instead of titatium & elastomer strap together. I never leave home without it.


Great gear!!   March 6, 2002
 1 out of 1 found this review helpful

Just got my Observer and I couldn't be happier! Despite some of the reviewers comments on the instructions, I found them easy to understand. I spend a lot of time in the field and am looking forward to putting this watch through its paces.


All well and good, but it's 1/3 smaller in another way....   February 1, 2002
 4 out of 8 found this review helpful

Just a brief note-
The Observer is 1/3 smaller than the other Suunto watches, which is fine if you are a small person or have small arms/wrists. If you have a large wrist like my husband does(8") the Observer WILL NOT FIT, at least the SS/SS and TI/TI versions.

This was a major bummer Christmas Day!

We returned the watch and that was the end of it...