stevesisti
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Posts posted by stevesisti
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Have any of you done much with making a lake chart? I have made a couple of maps using the procedures outlined here and tey work great. A friend just picked up a 76Csx and we want to make a detailed lake chart. No need to spend $150 or so to pick up Garmin's bluechart when his boats only resides in one lake.
I have read some of the help files and such, my biggest question is where can I get lake data (depths, bouys, etc.)
Thanks for any help!!
Jeff
http://nhdgeo.usgs.gov/viewer.htm
you can download shapefiles of hyro data..there is no bathymetric data...that info is pretty hard to come by and is generally not made available to the public..unless it's one of the "bigger" lakes.
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Thanks, but I am still all confused by this in spite of normally being able to figure out this kind of stuff. I am about to go crazy trying to figure this out. I just do not understand why someone has not made a program that easily does this stuff-I would pay a lot for it.
Anyway, is there somewhere that explains the steps well? I've tried to figure this out and it does not work.
I do not have a pv.txt or know how to make one. Can someone diret me to directions on what to do with this?
I am trying to convert track files into transparnet trail files in a map. I've loaded them in GPS MApedit, converted them to trails and set the zoom levels. (Not sure if they are right though). I then go to export garmin img file. It then runs G:\Work\GPSmap0060\cgpsmapper.exe
I then get:
GPSmapper command line utility version: 0060 Mar 23 2003
gps_mapper@gps.chrisb.org
Shareware edition
Without SHP support
GPSmap import library version 0010
Importing data
G:\Work\GPSmap0060\cgpsmapper.ini found!
POI info sorting
Layer >>>>>>0<<<<<< generation
Nothing was imported into Layer0!
Layer0 cannot be empty!
This application has requested the Runtime to terminate it in an unusual way.
Please contact the application's support team for more information.
Any help will be greatly appriciated.
Did anyone ever figure out the Layer0 cannot be empty! problem?
I wish someone would make one of these mapping programs that is easy to use! I would buy such a program.
Ok I see what you are saying...the pv.txt file is used later on when you are trying to put your map into Mapsource. That is not the problem here.
Once you make your map in MapEdit, before you try to convert it to a .img file, you must save it as an .mp file. Have you successfully saved your map as an MP file, if so, you can e-mail it to me and I will give it a quick check to see if it will compile here or what is possibly wrong..
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Did anyone ever figure out the Layer0 cannot be empty! problem?
I wish someone would make one of these mapping programs that is easy to use! I would buy such a program.
If you are referring to the error message when running the cGPSMAPPER command line for converting the .img file into the TDB and pvimage file, it really has nothing to do with layer 0, as you might "normally" interpret it. In order to run cgpsmapper program, the pv.txt file and the .img file have to be copied from where you have them into the same folder as the cgpsmapper.exe file. cgpsmapper only looks in that folder for the files...if they are not there, cgpsmapper will not look elsewhere and will deliver an error message. You need two files in the folder to successfully compile the map. One is the PV.txt file, into which you put all your specific map names, levels , and the name of the .img file you want to convert..if there is no reference here to the .img file, you will again get an error message. The other file you need is the .img file you got from Mapedit, to which the pv.txt file refers to during processing.
When you go to compile you must get the dos prompt, and navigate to the folder where the cgpsmapper.exe file is located. You can get the path statement by leaving the window of the folder where gpsmapper.exe is located open on you desktop...again, if you don't navigate to this folder, you will get an error message when compiling. "layer 0 is empty" warning is caused by several different errors, which have nothing to do with layers in the original garmin .img file you have already created.
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Is something else available ie. different file format, other source for the same data on the National Forest ?
There are a lot of different data sets on that page from bald eagle locations to the park perimeters. As to entering the wrong datum, if you look under "metadata" and scroll down you will find the datum that pertain to the files. Whether you can somehow make use of the data depends on just what exactly you want to do with it..eg. just show it on a map, transfer waypoints to GPS, make your own map..etc.
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I've modified a 24K topo map. I deleted non-existant trails, added trails not shown, added new jeep roads, added wildlife management area boundaries, corrected stream names, deleted non-existing features, added new features. In short, I've completely revised one 24K map to accurately reflect everything that is there.
The map sellers (including Garmin, Magellan, DeLorne, Nat. Geog.) rely on current USGS information which is completly out of date. I added it as a custom map to my unit, but loaded the surrounding 24K Garmin maps. For the map sellers, providers, it's easier to sell then to make over new maps.
Currently doing something similar but for french and belgian topo maps. I just began 4 days ago learning/playing with various tools but can see they did a sloppy job as they did not care to name lot of places, items, streams etc..., just put generic names like "stream" "buildings" !
Formating, colors, zoom level are sloppy too.
I guess the market is not very big in Europe for these because definitely the GPS can do better when I see all the possibilities available.
What tools do you use ?
Do you have by any chance a table showing the coding of the formating data included with an item name ?
Eg with Mapdekode and Trackmaker: Hardwood<S=&H1F><Z=1>
S seems for the string format color and appearance and the Z for the zone/zoom level which are obviousely translated from the Garmin img binary format.
As a National Map Corps Volunteer in the USA, I have been extensively hiking all of the trails and exploring the areas in this 24K Garmin map which is the same as the US Geological Survey 1:24K maps which is the maps that all of these USA map makers use.
I opened the original Garmin 24K map with GPSmapedit, and used this program to edit the map.
Hikes and some off road trails were saved as tracks and other features were obtained as waypoints (if they were different then the Garmin map information) and stored and compiled in a Mapsource gdb file. Then added the Mapsource gdb file and added the tracks and waypoints.
Garmin uses 3 map levels, so I paid carefull attention in assigning lesser features to the lower level(s).
I obtained a shape file from a state GNIS department which showed the boundaries of wildlife management areas, and added the boundaries as polylines.
Of course, to make the map back into a Garmin Mapsource file, I used GPSmapper.
To see the coding of the maps, instead of opening the mp file with GPSmapedit, use notepad to see the coding and also allows editing.
GPSmapedit has default values (colors, line styles, etc.) for various features (points, polylines, polygons), but I'm not familiar with changing these values, but are the same as the Garmin 24K topo.
Just curious...with the original version of of map edit, I was able to open Garmin image files, I'm now using ver 0085 and map edit will not allow me to open the file....maybe this option was allowed in "early" versions and discontinued later on...any idea of how to once again access the Garmin files.
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Is anybody noticed that on City Navigator North America V8 the street address (civic numbers) are offset? They are so offset that at the end of the street there is numbers that are not existing. It's like if they put too many lots per street.
The actual street address is calculated by by taking a "starting" number and an "ending" number and evenly, by distance, distributing the numbers over the street length segment. In actuality this has a very poor accuracy in pinpointing a specific street address because common sense tells you "even" spacing between different "properties" rarely, if ever, occurs in "real life". For a street address to be very accurate, the unit would have to have the GPS coordinates for each address, which it doesn't have and won't have for the foreseeable future. In practice, when finding a specific street address, you should consider the indicated address as an approximation, and visually look for the address when you get "close". I have seen many addresses that by coincidence, are remakably close to the actual location (pretty much even spacing of properties) and I have seen addresses that weren't even close. No sense in calling Garmin or anyone else regarding the issue. The current mapping units just don't deal with specific addresses...only an approximation by the method described above.
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I had been using a Garmin Etrex to take points. I would then use DNR Garmin ( a free program I found online from a university) to download the points and export them as a shapefile that I then use in Arcmap.
It doesn't work with my new reciever. Any ideas?
I could try to export the data as a table and create a shapefile to view in Arcmap but I was hoping someone might know of an interface between my new Garmin that would produce a shapefile.
Gave you bad info...be back.
MapEdit will directly import your GDB track file Although I haven't used this method myself yet..it looks like it will also export a shapefile. As mentioned earlier...if you liked the way to were doing things, DNR Garmin should work with the 60csx...I would investigate that approach
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I had been using a Garmin Etrex to take points. I would then use DNR Garmin ( a free program I found online from a university) to download the points and export them as a shapefile that I then use in Arcmap.
It doesn't work with my new reciever. Any ideas?
I could try to export the data as a table and create a shapefile to view in Arcmap but I was hoping someone might know of an interface between my new Garmin that would produce a shapefile.
Gave you bad info...be back.
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Get some silicone spray, put a little on a cloth and wipe on the screen....wipe off thoroughly...do the same to the inside of the vinyl window in the garmin case...they shouldn't stick anymore.
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Has anyone experience or heard of means to modify Garmin Topo maps in order for example to add some path, names ...
I have seen post in the past regarding map creation, quite a lenghty and complicated process but none to just modify existing maps.
Personally I would leave the Garmin maps alone...I make topo overlays for my favorite areas using GPS mapper..It is involved the first few times you do it with a steep learning curve. Nothing hard about it, just a lot of little steps where a simple error in a path statement causes the map to not load. I can put 6 7.5 quads together , with contours, rivers streams and lakes, in about an hour. The "overlay is transparent and you can have it and city select showing at the same time. You could do the same having one "overlay" that has your trails on it. Done properly, it is selectable in "Mapsource" as a standard map and when in the unit can be toggled on and off. To be able to do trails you need to convert the Garmin file to a shapefile and then import into GPSmapper. Can't remember which freeware program did the conversion. Contour height levels are not shown becasue of zoom level but they are there. This is a small pond in the Adirondack Mountains.
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We need a science guy to explain the workings of a barometer better than I. Someone?
Page 76 of the manual states that trip data is not recorded in "Fixed Mode". Also-
Without knowing the exact details I will say that a Barometer to read correctly at sea level and at high altitude an adjustment must be made. The Barometer in my office can be adjusted mechanically while I suspect the Barometer in the 60CSx is adjusted with an algorithm where altitude is one variable.
Hopefully a smart science type will jump in and explain better the whole process and correct any incorrect statements I have made in my limited knowledge.
Just thoughts...
I'm with michael cook on this one...If you tell the unit you're at a fixed elevation, that means any and all pressure changes should be viewed as resulting from Weather variations and not altitude variations. As such the altitude reading should not change...why bother asking if your evevation is "fixed" if the unit is just going to ignore it and do what it normally does. My hunch is that the "fixed" option is a redundancy on the auto cal function, temporarily overriding the GPS sat derived auto cal feature until you turn it off.
When given a known altitude, the unit takes it's barometric sensor reading and then based on the altitude, derives the Barometric pressure at sea level, and "re-sets" that number as a base figure.
When you calibrate the unit by giving it a known atmospheric pressure, this number should be from a reference station and is based on the pressure at sea level...if the sation is not at sea level itself, it has been adjusted to reflect what the pressure would be if it were at sea level. That pressure is then "re-set" as the base figure.
There are only two variables that affect the barometer and cause a change in the pressure..one is the altitude which decreases with height...the other is the movements of air masses of greater or lower pressure..Highs and Lows.
If you interested in just using the unit as a weather barometer, removing any errors from the auto cal function should leave you with simple barometric changes that are weather related .. eg not subject to the autocal errors cause by bad sat configuration, or antenna orientation.
If Michael is seeing a fluctuating altitude reading in this mode, that just seems wrong to me, unless it's just one of those "not so smart" implementations by the Garmin programmers. For the common user, if he sees an altitude movement while in the "fixed elevation" mode, it's natural to think the unit is not working correctly. Not quite sure on this as I haven't used the feature a heck of a lot...but ambient pressure to me is the total unadjusted pressure reading at Your current location. Whereas the barometric pressure is the pressure corrected to what it would be if you were at sea level.
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Now we all should know that condensation has nothing to do with being waterproof ..... as we have seen with many cache containers. Your problem occured by placing the unit out in the direct sun ... in a damp environment. Place the unit near a dehumidifier or even under a light bulb. It will dry out and come back to normal.
Condensation occurs from the trapped air in the case letting go of its water molecules due to heating.
If it does not .... then call Garmin. They are very good at service and will most likely take care of you even though you are out of warrenty by one month.
ImpalaBob July 3, 2006 - 1000 finds with Koikeeper!!!!!!Wow you're violating the rules of basic science here Heating doesn't cause condensation...cooling does. And neither one of those would occur if it were not for Excessive amounts of moisture bieng present in the unit in the first plase. I've used my GPS on my Kayak hundreds of times leaving it directly on the Kayak deck in full sunlight and have never had a problem.
To the real science , not voodoo magic...internal fooging of the lens is most times the first sign that water has penetrated your unit...unless you have a "large" failure or dunking where a significant amount of water enters and is visible, you really wouldn't know there has been a leak. It doesn't take much water at all, to be heated and turn to vapor and then condense on the screen. Only an idiot, while he still has potential warranty help available, would put a hair dryer to the unit...How are you going to dry it if the unit is sealed...all your doing is putting more water into vapor and sending all over the internal electronics..if you were to self dry the unit, you would have to open the seal on the main body case and then try to dry it. Of course if Garmin sees that you have opened it, they just might not be so willing to help.
Science 101 also tells you that air does not hold or let go of water vapor. Water moves back and forth between liquid and vapor phase having solely to do with the energy levels of the molecules involved. Air does not hold anything. Contrary to what you say, Heating will cause water molecules to move to the vapor phase. Cooling, as in splashing cold water from the paddle over the lens screen will cool the air just under the screen and cause condensation on the underside (internal) side of the screen. Again, for this cooling to cause condensation under the screen, there had to be a "significant" amount of moisture present in the first place for the heat/cool condensation cycle to happen. There just simply should not be this amount of water vapor inside the unit.
Send the unit back and hopefully they will replace it...Many electronic itels that were "recovered" by their owners only wound up failing several months later...corrosion on the circuit board being the main killers.
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If the condensation is on the "inside" of the unit I wouldn't even fool with it...even if it recovers now, there is no guarantee it will be ok in the future...especially if you were paddling in salt water. Being one month out of warranty ususally isn't a problem for Garmin...send it in and have then take a look at it. Go buy yourself an Auapak ($ 10.00) for carrying the unit when on the water...doesn't interfere with signal and buttins are easily operable. Pak comes with a carbiner and tether so you can snap it onto yor deck lines. If it does recover and you wait a few months to "see how it goes", garmin might not be so willing to replace the unit.
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I don't know what the advantage would be to having the ability to display the GPS (satellite) derived altitude. You'll just wind up aggravating yourself looking at the difference between the barometer and the satellite elevation. The problem has always been that with auto cal "on", the gps using the sats, corrects the barometer altitude. This works reasonably well until you get yourself in a position where you have a bad sat configuration, or some of the sats are blocked because of the terrain you are in. Of course none of us know what logic Garmin uses as to when and how it will decide whether a given sat altitude is "accurate" enough to be used as a "correction". I can say from using it a lot, that using just the barometer is a lot more accurate than relying on the GPS sat side to add it's "corrections". Of course that applies only when you don't have a significant movement in atmospheric pressure. It also means that you have to calibrate the unit from a known atmospheric pressure or elevation which sometimes is a PITA. For ease of use and more reliable results, I am more comfortable with the topo contour lines, as I make my own and they are more detailed than Garmins. This method doesn't of course give you a pretty altutude graph on the GPS., something I would find as an interesting reference, but very non-interesting if it's not accurate....which it isn't.
I have always had a hunch the GPS sat correction doesn't have, or doesn't have a good enough logic circuit to decide when it has an accurate enough sat reading to apply the correction. To check the variation on the GPS altitude, try taking several readiings ath the same spot on different times of the day using the sat page and GPS the GPS altitude...with my 60CS I can see a "big" swing in altitudes....
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I'm not sure . . . but it is usually true. Someone more knowledgeable about the maps will have to explain it.
You might logically think that but that is not the case. I have found the "corners" on the base map to be off even more than "straight line" sections. One would think in a long arcing curve that a point would be used that is tangent to somewhere along the curve but it doesn't work that way. I can see the same thing in maps that I make myself...cutting down on the amount of points used in defining a road leaves you with all sorts of weird shapes with no apparentlogic behind it. Bottom line it's nothing to fret over, just understand the basemaps do not have enough vector points to create an accurate profile of the roads you see.
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This thread topic is well timed
I'm trying out a Vista Cx that I just purchased today. So far all I've done was pop in some new batteries & was watching its performance as I was driving home. I haven't yet bought any enhanced maps for it, so am only watching the basemap...
Well, I'm travelling North along a road that happens to be on the basemap and, just like the OP was mentioning as well, my plot trail is showing me travelling along at 60' west of the road for the whole duration of the trip (about 30 miles). Umm,, should I be nervous about this?
I'm going to try some more tests before getting really upset about it, but am a bit disillusioned about the performance of Garmin's flagship eTrex...
Relax...the basemaps are terrible.....basemaps use very few vector points...Imagine the shape of Florida made with only three points...you're looking at a "point angle" instead of a rounded tip. It's impossible for your track to stay on this "abrreviated" map because using so few points it can only approximate the contours of the real highway.City Navigator uses many more points in creating the contour of roads. You won't have a problem with more detaild maps loaded. In your case the track is correct and the map is "wrong" (or poorly detailed). Looking on your gps, if your familiar with your local roads, you can easily see that the basemap depiction doesn't come close to approximating the real roads. I was horrified when I trid to navigate with the basemap....getting City Select made me very happy.
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Even with unlimited track usage you still have no way of linking a photo after the fact with a location unless you keep a log. Even with a log, depending on your camera (Digital I guess), the numbering sequence will only go so high on your memory media, then you have to start over again at zero...which will leave you with duplicate numbers..again, unless you have a way of re-naming or re-numbering the shots in camera or after the fact.
You do have 500 waypoints which seems to probably be enough for those "on-the -road" scenics we always seem to forget where they were taken. You can mark a waypoint whenever you take an image of note and add a descrip to the waypoint...or have the waypoint the same # as the image #.
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There is no such thing as "waterproof". Many electronics items have a "waterproof rating" which is based on "temporarily" submerging the object at a certain depth for a given amount of time. While this may be an indication of how well the unit is initially sealed, it's no guarantee your particular unit will survive a soaking. The Garmin units have many seals... battery compartment, lcd lens, all the buttons etc. It only takes one of these seals to have been "pinched" when originally manufactured, or moved out of position though wear for the unit to "take on water". I have used my 60CS and a "waterproof" camera in "light" rain with no ill effects. I know several people who have lost cameras when using in only light rain, and several who have never had a problem, constantly using them exposed to light rain.
As I use my GPS a lot and the buttons have probably seen "significant" usage, I now carry an "aquapak" water proof bag ($8.00) that just fits the GPS, allows access to pushing buttons, and doesn't affect the reception at all. I have used these bags for years and never had the slightest leak, so their reliability gets a pretty high rating from me. The unit in the aqua pak floats very well as I found out when I saw it trailing behind my Kayak on its lanyard. The pack can be folded and stuffed in a pocket when it's not required.
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The 60csx is my 7th handheld and is so much better than anything else I have owned. Buy one and enjoy it rather than be perplexed with trivial issues.
Regards,
John.
\If it's like the 60CS, when you lose sat contact or turn the unit or track record on/off, the track log gets split into a new section. You can just join them in Mapsource
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Check out the Trimble GPS tutorial as mentioned in POST #2. When they get to the part about magnetic compasses and barometric altimeters, post a reply here and then we'll discuss it...
And yes, I am a pompous a§§ when people refuse to listen to common sense.
You miss the point again, but after this I'll leave you on your own to deal with your problem. Depending on the unit and user slelection, the GPS unit can use either the barometric sensor, the GPS satellite derived altitude, or a combination of both, with the GPS altitude "correcting" or calibrating the reading. I don't think you're that ignorant, but using a Garmin 60s series unit, and turning off the GPS chipset will leave you with altitude readings on the altimeter....I'll say it slowly...turn off the GPS and you still get accurate altitude readings from the unit....the readings are very accurate, and have nothing to do with GPS chipset in the unit. So, for those who can't read others writings without inferring things that aren't there..this might help you. Based on Garmin 60CS
GPS unit without barometer = Satellite derived altitude readings
GPS unit with barometer in autocal mode = GPS altitude readings derived from barometer which is calibrated by GPS derived altitude.
GPS unit with barometer and autocal off = Altitude derived from Barometric sensor only. 0, zero, nada, zip, non-existant, contribution made by the GPS chipset.
Personally, I find the GPS contribution to be the leading cause of inaccuracy. I have repeatedly checked satellite derived altitudes over a 1/2 hr period and they were all over the place....nice day, no weather change, I shut the autocal off and the unit is much more accurate.
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It's a question of semantics....If by GPS, you mean the whole unit..it has two sources in the units with a barometric sensor. If you mean just the GPS "chip", it's satellite derived.
It's NOT a matter of semantics! It's a matter of understanding WHAT the subject matter is!
AGAIN - READ THE OP'S QUESTION!!!
How does a GPS know the elevation you are at?
Don't read anything into this! MOST GPS RECEIVERS DO NOT HAVE SENSORS!!! THE ONES THAT DO HAVE THE SENSORS USE BAROMETRIC PRESSURE FOR THE ALTIMETER FEATURE. THIS HAS ABSOLUTELY NOTHING TO DO WITH GPS (other than the fact that the device happens to be on the GPSr). THE ALTIMETER IS OFTEN CALIBRATED BY - GUESS WHAT...? - ALTITUDE DERIVED FROM GPS DATA! SENSOR-EQUIPPED MODELS OFTEN IGNORE THE GPS ALTITUDE AND DISPLAY THE BAROMETRIC PRESSURE ALTITUDE - BUT THAT'S NOT "How a GPS knows the elevation you are at"!
GPS RECEIVERS DERIVE ALTITUDE FROM CALCULATIONS FROM SATELLITE DATA - PERIOD!
W.T.F. IS SO HARD TO UNDERSTAND ABOUT THIS ISSUE???
Boy you must really be some kind of a pompass a**. Try not to get your undies all bunched up, come down off your throne and listen...that's right, listen to what someone is saying.
As i said, it's semantics....I see now you have changed the OP's words to "receivers"....he never said anything about the receiver...he said GPS. There are all sorts of altimeters out there, most wrist styles rely on barometric readings( you know, the ones worn by mountain climbers). Many GPS units can use both, with an option to have the "GPS" chipset (satellite) calibrate the pressure derived readings. In truth, on the Garmin units with pressure sensors, It's this autocal feature that frequently adds error to the altimeter reading. Anyone can verify this by standing in one spot and asking the unit to give you the "Satellite" derived altitudes...they vary by a wide margin over a period of minutes, depending, as does your location, on the configuration of available sats and the orientation of the unt. On a clear day with little or no change in the pressure at sea level, using the altimeter with the autocal ("satellite" derived) function off, the altimeter is much more accurate. Of course this leaves you open to errors if there is a weather realted drop in atmospheric pressure at sea level.
To each his own on how to deal with the accuracy or method of using the elevation data.....but I can simply tell you the altimeter works fine, even better, with the GPS side of the contribution turned off.
Lastly, I feel badly if no one listens to you at home, although I can sort of see why, with the attitude you have about anyone disagreeing with you. But you should leave your frustrations at home and not bring them to this forum. And try to grow up a little...using acronyms like W.T.F. illustrates your selfish, childish attitude.
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It's a question of semantics....If by GPS, you mean the whole unit..it has two sources in the units with a barometric sensor. If you mean just the GPS "chip", it's satellite derived.
In my 60 CS, if I turn the "GPS chip" off, the barometric sensor still records and diplays altitude readings on the unit. So the source of the data is not "satellite" derived, but rather barometric sensor derived.
In a unit without barometric sensors, the only source of elevation data is from the GPS "chip" itself...satellite derived.
Looks like you owe each other a beer
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Maybe this is useful?
Ambient pressure is the pressure that the sensor is detecting. Barometric pressure is the calculated pressure for sea level based on your altitude. So at sea level the ambient pressure and Barometric pressure should read the same.
Air pressure can change due to altitude changes or changes in the weather.
As you change altitude both the Ambient and Barometric readings will to. If your altitude remains constant, but the GPS starts to show an elevation change it means the barometric pressure is changing, which can mean a change in the weather.
Well, there's sort of a little conflict in what you are saying...although I don't understand this completely, here's my take....
As you change altitude the ambient pressure should change but the barometric pressure should stay the same, if it's definition is pressure at sea level. The only time it would change is if the weather brought in an air mass of higher or lower pressure. This would be true I think if the unit was in the mode where it didn't auto-calibrate eg. take altitude calculations convert to pressure and then subtract to re-adjust the barometric at sea level.
In auto cal mode, the unit would take a GPS altitude, convert it to an equivalent Known pressure for that altitude, see how it differs from the "ambient" reading you have, and then adjust to come up with the updated barometric at sea level.
A change of 1" of Mg in your reading represents 1000 ft approx (good ref. up to 10,000 ft or so) As an extreme example, if you left in the am for a mountain hike and hurricane gilbert blew over without auto or manual calibration the drop from 29.7 average nice weather day to Gilberts 26.7 would represent an error of 3000ft in altitude. Of course that drastic a drop doesn't happen that quickly, but the point is that it doesn't take much to have an error of sizeable proportion if the unit is not either manually (known elevation, known barometric station reading) or automatically (GPS derived altitude)calibrated. In the case of my 60CS, I believe the GPS derived altitude for one reason or another leaves a lot to be desired, as I believe it is the largest factor in the unit not being as accurate as it could be. Just using the barometer alone, it tracks very well with a barometer i have at home...the GPS derived altitude can vary by as much as 20% when several readings are taken within a minute or so while I am standing still. I would guess the very nature of being on one side of a steep mountain with a less than stellar satellite configuration could case the GPS derived altitude to be off target.
Steve
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That was my understanding too (That LiIons were better). I wouldn't know where to look for evidence though.Does anyone corroborate the LiIon discharge rate? I was under an impression that they held their charges much better than NiMHs...although maybe I'm thinking about non-rechargeable Lithium batts. I'm not too lazy to ask, just to lazy to search out an answer.
Numerous sources quote the self-discharge of lions as 3-5% per month.
ImpalaBob July 3, 2006 - 1000 finds with Koikeeper!!!!!!
Rolling one's own maps for a Garmin 60x
in GPS technology and devices
Posted
Note that MapSource cannot display multiple maps at the same time. So you cannot see your trails overlayed on top of CitySelect or the like. You now select all the maps from all the map sets you like, so that they are pink, and download to GPS. Done.
Jan
Not True at all....When you create a map in MapEdit, check the map option to make the map transparent. I have created contour plots for 6 different 7.5 usgs quads in New York and they overlay City Select with no problem. I also have many of the streams which City Select has missing loaded in the same fashion. You can see both maps at the same time, and toggle back and forth between both if you desire, or leave both on at the same time. They are selectable and loadable as seperate entities in Mapsource, just like any other Garmin product.