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It was five in the morning and the gates of Victoria Falls National Park weren't open. Regardless of the time of year, the park opens at 7 am and closes at 6 pm. But I knew sunrise was just before 6 am, so I did what I had to do, I climbed the fence and let myself in.
I knew exactly what time the sun was going to rise because Galen Rowell had told me the night before. And Galen knew because he was wearing a Casio watch that allowed him to punch in the LongLat coordinates to get the sunrise and sunset information. Immediately, I wanted one of those watches.
When I got back to the states, I went from store to store looking for the watch, but none of the places had ever heard of the model (Forester 1879 FT-200W-1V). Eventually, I took my search to the Web, and voila, there it was, and a bargain at about US$55.
In operation, the watch is pretty much like any other Casio watch except that it has this unusual display above the clock information. That's where the Casio displays the sun and moon position, as well as the moon phase. To calculate sunrise and sunset, you use a superset of the set time function to enter the GMT, Longitude, and Latitude information for your location. The Forester only allows you to enter LongLat in full degrees, so there's always going to be a slight variance between what the watch reports and the actual rise and set times (unless, of course, you're standing right on a degree intersection). Even so, I've never found it to be more than four minutes off in its suggestions (Casio claims five minutes, plus or minus). That's close enough for me. It does take the watch a while to calculate when you enter a new position, and even when you ask it for the rise and set times, there's a few second delay before you get it. That's not really a problem, in my opinion. If you need rise and set times reported immediately and accurate to the second, you must be some kind of rocket scientist, not a photographer.
The backlight is not quite as bright as those on the ubiquitous Timex Ironman watches, and it shuts off quickly (probably to preserve the battery). On my watch, the Fwd and Rev buttons don't work as indicated by the manual, but I've learned to cope. You'll need to read the manual carefully to figure out how the upper position display works, but once you understand how to read it, you'll find it useful for estimating moon positions (allowing you to scout shot locations during the day). The moon age, for some reason, only updates once a day, even though it shows in tenths of days. You can kind of predict moonrise and moonset times from the moon position, by the way.
A simple watch that performs a useful function for photographers. Recommended.
PE writes: I read your web-page with interest, and have been given a Forester for Christmas, by my dear partner (with the hope that I may be able to catch a few more fish). I have set the Latitude and longitude according to the atlas and the time difference from GMT and allowing an extra hour for daylight saving. I have noticed that the high and low tide display varies by about 3 hours against printed tide charts for the area. I don't suppose that I should growl too much as the times that I have been out fishing, when the "fish" is displayed, I have caught fish. This maybe entirely co-incidental, but prior to using the watch, my fish catching was very spasmodic. I don't know whether you may be able to check my settings, but I live in Moruya on the far south east coast of Australia and as far as I can work out we are GMT+10 hours (+1hour for DST) Lat150 Deg east, Lon 36Deg south. I would be very interested to see if you can throw any light on the variation.
Thom's reply: Unfortunately, tidal information isn't simple to calculate. I'd give you the formula here, but unfortunately it takes several pages of code to do just the US correctly. I really doubt that Casio went to the trouble of localizing the basic tidal calculations, which is, I guess, why they call it Fishing Time instead of Tide Times. What the watch seems to do is the basic moon/earth positional calculations, which do have the primal impact on tide times, but aren't precise in themselves.
JM writes: The answer to the question about the tidal query submitted by PE was only partially correct. The watch delivers lunar positions not tidal positions even though both are related. The purpose of the monitoring of the lunar positions is that there is a theory called the "Solunar theory" offered by John Alden Knight in Moon Up Moon Down, published in 1942, which indicates fish and other wildlife respond to the magnetic effect of the moon passing around the earth, hence the importance of predicting the 'hour angle' of the moon for the day or for some other nominated day. check out the web for solunar tables; though they don't give the formula the result is the same as using the Casio function to calculate the optimal times (lunar only).
Thom's Reply: Thanks for clearing that up.
JS writes: I used my Forester for tides for years. In south Florida, just skew the GMT to -9 hours (or is it +?), anyway been accurate for years. Unfortunately, sunrise and set info will then be way off, but for me, (a yacht captain) tides are more important. Alas, I ripped it off my wrist the other day, and am now in need of a replacement. I can find one at a local Bass Pro shop (or on-line) for $39, but think I may go for a Casio GL-150, which is a surfing watch that has tides, sun set and rise, moon phase, and a count down timer (http://www.shop4brand.com/store/gl150.html ).
Thom's Reply: Without modifiers, basic tidal calculations are usually only accurate near the equator. As I noted, Casio provided this basic function, but didn't localize it, which means if you live on the Bay of Fundy or in the Alaska Inner Passage, well, the watch just isn't accurate, no matter what you do. But perhaps the GL-150 is smarter.
BB writes: After an extensive search of the web, and after reading your review, I finally decided to buy the Casio FT-200. It helped me very much, that you quoted the full name, including the module. no. 1879, which allowed me to visit www.casio.co.jp/pdf/index_e.html and download the manual. Thank you for this information. I am very fond of my new watch (it's called the "GeoTrail FT-201" instead of "Forester FT-200", but the look and specifications are exactly the same.) One thing still puzzles me: You mentioned in your review, that "You can kind of predict moonrise and moonset times from the moon position". How do you do that?
Thom's Reply: The moon icon position roughly corresponds to a position in the sky. You won't be very precise in your guesses based upon this, but over time you develop a rough approximation of what each position means. As for the watch name, Casio makes several very similar watches, and the names seem to vary in different countries, probably due to trademarks. The model number (FT-201, FT-200, GL-150, etc.) is the most reliable way of indicating a Casio watch version and what I would do searches on (e.g., "Casio GL-150 typed into Google.com's search box).
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