What is a good Topo map for use on a Magellan Triton GPS?

Boyd

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I didn't have any issues installing under Vista 64 bit. Looks like you solved your problem though.

Globalmapper is a regular computer program, not a subscription. If you want updates after a year or so, then you have to buy the new version, but your old version will continue working. You can also get it cheaper than list price. Look at some of their partners - I got my copy from DRG Maps: http://www.globalmapper.com/community/partners.htm#USA

I used the example of the buildings above since it was easy to compare resolution of things like cars and lines in the parking lot. But yes, the NJ2007 photos were taken in winter and show quite a lot!

You will not be able to download the imagery for the whole pine barrens in a month (unless we have a different definition of the pine barrens :) ). I worked on it for a number of months and have most of the pines, but not quite all. We are talking about, perhaps, 150GB of data.

If you do try to make a lot of maps using the free key, then you should probably do the downloading before using the key. You don't need Globalmapper to download the files, just to export them in the right format for TritonRMP.

Glad you got it working. This high resolution imagery is one of the nice things we get in exchange for all the tax dollars we send to Trenton. :)
 

manumuskin

Piney
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i am having an issue making the maps out of the images.if i make the image too big then it is too big for my 4 gig card so i tried making a much smaller map and forgot then when i calibrate a too small of an area it goes onto my triton but the map will not show up.i must experiment to see how many tiles i have to make a map of in order for it to be large enough to show on triton but small enough not to exceed my 4 gig card.yes your right but it's too late,i already had the key sent to me,can i get another on my wifes email or do they go by isp number? no matter.if i like it well enough when i figger it out i will buy it.
Al
 

Boyd

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Have you tried experimenting with different resolutions? If not, try what I suggested earlier and export at 4 feet per pixel. You will lose some detail but it will reduce your file size to 1/16 of what it is at full resolution (4 x 4 = 16).

Now go File > Export Raster and Elevation Data > JPEG (or choose any other format). You may want to reduce the resolution of these images because they are huge. In the export dialog box us "Click here to calculate spacing in other units...". Choose Feet if it isn't already selected. Now use another number for x and y. This determines how many feet each pixel will represent. The native format is 1 foot per pixel, which is pretty impressive, but huge files. I think 4 feet per pixel is a reasonable compromise for many purposes.

If that reduces detail too much, try a setting of 2 feet per pixel. That will still reduce the file size to 1/4 of full resolution.
 

manumuskin

Piney
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i want full resolutio.i will have to figure out the smallest area i can make a map and still have it show.even if i can only put one map on .i will get more and bigger cards if i have to.I like the full res and will play with none less.
thanks for all this info.if i can not get these onto gps i can still make image files of them and put them on there as reference.
Al
 

manumuskin

Piney
Jul 20, 2003
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I have finally figured out at what size to make maps.i tried 4 tiles and the map i created was so small that the calibration points were too close together for the triton to display the map so i went to 16 tiles a four tile by four tile rectangle(becuse lat dgrees are further apart here then long) and the file was over a gig and triton RMP informed me I had run out pf memory so i tried a 9 tile map (3by3) and this brings me to a 95 meg map and is doable and quite beautiful on the gps.Now I am three days from running out on my free trial.I see it is over 300 bucks a pop for a license.i was thinking it was 1 something but i see thats for the update.i think i will have to save for this for awhile.the imagery does blow me away.I almost think I can make out some of the larger stones:)
Thanks for showing me this program.is their imagery of the rest of the USA out there comparable to this NGIN imagery?
Al
 

Boyd

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Glad you got it figured out. It's very satifying to make a map, then get out on the ground and use it. :)

I think you will find there are free or low cost alternatives for opening those NJGIN files, but I have never looked for them myself. You just need to be able to open either JGPEG 2000 or MrSID files, then export them in a format TritonRMP uses. You could probably get some help in the Map making forum at tritonforum.com.

Image quality varies by state. I have found some nice stuff for Pennsylvania here: http://maps.pasda.psu.edu/website/Imagery_Viewer/viewer2.asp?tools=PAN&mapX=311&mapY=223

New York orthoimagery is here, have not looked at any of it yet myself: http://www1.nysgis.state.ny.us/MainMap.cfm

You can go to the National Map Seamless Server and see what is available also. There's a lot of stuff here but the user interface is pretty confusing: http://seamless.usgs.gov/index.php
 

manumuskin

Piney
Jul 20, 2003
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Boyd,
these ngin aerials make great maps,the only problem is that they only display on the gps at the most zoomed in level which is 100 ft to about half an inch on the screen.once you zoom out to 200 or more feet the image is lost and the default map takes over.It may be unfixable since the images are so high resolution.is their a way to make the images/maps display at more zoomed out levels? the images are great for close ups but it's hard to nav a large area without flipping over to my topos and back which is a lot of button pushing and scrolling.
Al
 

Boyd

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Yes, I believe you can do this with TritonRMP. But this is one reason why I didn't enjoy making maps in Magellan's format. TritonRMP chooses a zoom level based on the resolution of the image you feed it. Since this imagery is such high resolution, that is why it's only working at very high zoom levels.

But you can put multiple images into one map, although I never tried myself. You would use GlobalMapper as I described earlier to re-sample the images at, for example, 4 feet per pixel then perhaps add another one sampled at 16 feet per pixel. As I understand it, the GPS would then choose the different images based on your zoom level.

This also goes back to my earlier comment though, that the 1 foot per pixel imagery is kind of awkward to work with and re-sampling at 4' per pixel might be more practical. I suggest that you sign up over at TritonForum.com if you're having trouble figuring all this out. There are people there who can help. Like I said, it all seemed like more trouble than it was worth to me and I use OziExplorer which doesn't have any of these limits. It zooms smoothly in and out regardless of what kind of images you use.
 

manumuskin

Piney
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I am on triton forums but the replies i get there often go way above my understanding. I can try again and see if I can filter the reply:)
does this oziexplorer work with triton? I doubt it,probably a garmin thing.
al
 

Boyd

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I use it on my Triton 1500, but it requires a touch-screen and I don't think your model has one, does it? Actually, it doesn't work on Garmin at all. It requires a GPS based on Windows CE, which is what Magellan uses for all of their products. Garmin uses its own proprietary operating system.

Unfortunately, making your own maps - especially with TritonRMP - does tend to get very complicated.... and frustrating! But keep on trying and you will eventually get the hang of it I'm sure.
 

Boyd

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Just a thought... before considering spending $300 on GlobalMapper (not that it isn't worth it), consider that you could get an Oregon or Dakota and a subscription to BirdsEye for about the same price - maybe less. After some initial mistakes, I have now discovered that this imagery is very close to the full quality NJ 2007 1 foot per pixel data. I would say Garmin has delivered on their claim of "sub-meter" resolution. See the info and screenshots I posted here: http://forums.njpinebarrens.com/f16/garmin-birdseye-aerial-imagery-subscription-7213/#post78480
 

manumuskin

Piney
Jul 20, 2003
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millville nj
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I think I'll stay with the Triton and deal with the lack of zooming out capabilities.if I'm going to an area repeatedly then as you say I can make multiple maps at various zoom levels which should correct the problem though I may have to go into the maps folder and switch maps each time.
right now I'm downloading the whole barrens then I'll activate a new two week trial and hurry up and try and make bmp files out of all the sets before the two weeks runs out and then make maps from them at my leisure.if time runs out I may just break down and buy globalmapper.heck you can even track with my garmin map 76 just like i do with my nat geo topo maps and a laptop.I'm sure theirs things I can do with the program I haven't even figured out yet.
Thanks for the help.these aerials should help a great deal in searching out survey lines for stone hunts.
Al
 
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