Oregon Map segments

[Stingingfork]

I'm new to this forum as well as to owning a GPS device. I enjoy hiking so I finally broke down and purchased an Oregon 550T while it was on sale so I can keep up with the different trails I hike on. I've been reading all I can concerning loading maps on the micro sd card and this thread has been informative but I have a few questions:
I just got off the phone with Garmin over another issue during the firmware update and I asked about the limitation of the quantity of maps on my Oregon due to the total number of mapping segments. He stated that the total no. of maps on my device couldn't exceed 3,500 segments and that for instance the Garmin US Topo 24K Southeast DVD's had approx. 1500 segments so based on that I'm assuming that I'm pretty limited as to the total no. of maps I can load on my Oregon. He also said that no matter the no. of subdirectories or file names that I placed on the maps I still couldn't exceed the magic no. of 3500 segments. Is he correct or is there a work around that he's not aware of? I purchased and installed a 32gb card based on the max. gb's I can install on my Garmin per their FAQ. Now I'm not sure that 16 wouldn't have been plenty.  Other than maps what else would you normally load on the sd card?  If I'm really limited to the total no. of segments where can I find out the no. of map segments that each map contains so I can stay below the 3500?

[maps4gps]

Garmin's birdseye raster imagery uses a huge amount of space.  These are not vector type map data in segments and will not count against the Oregon's segment limit.

Garmin uses a very small segment size so their vector mapsets will still be usable in most of their older GPSr units.

[Boyd]

I think the actual limit is approximately 4000 segments. But the pre-loaded 100k topo on your Oregon has about 450 segments, so that's where the 3500 number is coming from.

Yes, typically you will hit the segment limit long before you reach the storage limit (32gb), but it's completely dependent on the maps you use. There are no standards for segment sizes, it's up to the mapmaker. For example, your version of the 100k topo has 450 segments but the version of the same map that Garmin sells on DVD has about 6600 segments.

As maps4gps said, Garmin uses small segments in the DVD products so they will be more compatible with old devices that have small amounts of memory and no card slots.

Really, the segment limit won't be much of an issue for most people.

[Stingingfork]

Thanks for the quick responses. I went ahead and ordered a US Topo 24K Southeast DVD's which the Garmin rep said used about 1500 map segments and I plan on adding several from this site so where can I find out the total map segments that I've loaded on the Oregon 550T. I didn't see the number in Basecamp when I was building and loading some maps last night but I definitely want to keep up with them so I don't cause any software issues for the device. I'm sure as Boyd mentioned that the 3500 limit was less the internal mapping with the pre-loaded maps. But if the pre-loaded is so small why would the Southeast DVD's be in the 1500 range as stated by Garmin? Thanks again for your informative posts.

[Boyd]

The "why" has been answered twice above 

Garmin uses a very small segment size so their vector mapsets will still be usable in most of their older GPSr units.

As maps4gps said, Garmin uses small segments in the DVD products so they will be more compatible with old devices that have small amounts of memory and no card slots.

Basecamp/Mapinstall don't tell you how many segments you're loading. Just use Mapsource if you want to know, it shows the number of segments and the size under the Map tab on the left.

[Indrid Cold]

Basecamp/Mapinstall don't tell you how many segments you're loading.

My copies of MapInstall give a segment count. Are you not able to get one also?

[Boyd]

Haven't tried for awhile - this must be a relatively new feature because it has been a long-standing Mapinstall user complaint. Good to see that the developers are continuing to make improvements.

[dbperry]

OK, I'll bite....what happens if you exceed the segment limit? Pestilence, war, famine, and death?

Does the segment limit only apply to the 'active' maps being displayed, or all the maps loaded onto the unit (regardless of if they are 'active' or not)?

Is the segment limit the same for all models or does each model have a different limit?

[Boyd]

According to Garmin - and user reports I've seen - the results will be inconsistent. Some parts of some maps will not appear. It is impossible to predict exactly what will happen because it's map dependent. But only 4000 of the segments will be displayed.

The 4000 number is supposed to apply to the total segments of all maps on the device, whether or not they are enabled. This includes the basemap.

Older devices, like the eTrex Legend Hcx, GPSMap 60csx, etc. had a 2025 segment limit.

But strangest of all, the Nuvi series has no segment limits.

https://support.garmin.com/support/searchSupport/case.faces?caseId=%7Bfe363fe0-211a-11e1-73d0-000000000000%7D

Although other devices have a limit to the number of total map segments they can read, the nuvi line does not. When sending maps to a nuvi, you are only limited by the following:

Total available memory on the nuvi, if sending directly to the device
Total available memory on the SD card, if sending directly to a memory card
MapSource and MapInstall limitations

Also, no single map file can exceed 4GB. This is a limit of the Windows FAT32 filesystem used by Garmin.

[Stingingfork]

The "why" has been answered twice above 

Garmin uses a very small segment size so their vector mapsets will still be usable in most of their older GPSr units.

As maps4gps said, Garmin uses small segments in the DVD products so they will be more compatible with old devices that have small amounts of memory and no card slots.

I guess as a Newbie I'm missing something but how is 1500 map segments on the Southeast DVD considered a small amount if I am limited to 3500? Also where should I look on MapInstall to locate the map segment count?

[Boyd]

I guess as a Newbie I'm missing something but how is 1500 map segments on the Southeast DVD considered a small amount if I am limited to 3500?

I don't understand the question in the context of what you quoted above. Many older model Garmin models only had 24MB (that's megabytes, not gigabytes) of internal memory and no card slot for expansion. There were also some expensive older devices that only had 8MB. And other expensive models required proprietary garmin storage cards that cost hundreds of dollars just for 64mb.

With an old device like this, small segments were desirable so that you could cover the exact area you wanted. If a segment was, for example, 16MB then you could only load that specific part of the map, wasting 8MB of space in your 24MB memory. People did not think in terms of loading entire regions, let alone the whole US. Maps were originally stored on CD's that you had to insert everytime because hard drives were so small.

I know, sounds like ancient history, but many of these old devices are still out there. Until about a year ago there were still some in Garmin's lineup - even a couple models with serial interfaces (no USB). Garmin still wants to support these, and the DVD map products use small segments for this reason.

If that bothers you, choose the download version next time. I think you will find they have much fewer segments. For example, the DVD version of US Topo 100k has ~6600 segments but the download only has ~450 (like the topo on your Oregon). These are the versions designed for people who want to keep a lot of maps on the GPS. I don't have any specific data on how many sectors the download products feature. You could contact Garmin and ask.

Personally, I don't need all that stuff on my Montana. I keep it lean and mean with just the topo maps I need for my usual travels, plus the download version of City Navigator. I doubt that I have any more than 1000 segments total.

As for what you need or expect, only you can say.

[Indrid Cold]

Also where should I look on MapInstall to locate the map segment count?

I going to let you take a guess as to how many map segments I have selected here:


[spoiler]See the red arrow? The answer is 57.[/spoiler]

[Stingingfork]

Boyd, the only issue that I was bringing up with the context of my message was that I hardly think that 1500 map segments would be considered a small amount when it limited to 3500 segments to start with. I got a great deal with the DVD so that's why I went with that format but based on what you've stated I'll be sure to look at the downloads in the event I need some when traveling West. 
Indrid Cold, Thanks for the tongue in cheek reply as to the map segments, I needed a laugh this evening and I'll be sure to check this out on the next map I load from Gpsfiledepot. I want to try the trail maps that I've read about. I really appreciate the availability of maps on this site as well as the knowledgeable moderators and members. I actually got to use my Oregon for the first time this past Saturday on a 15+ mile day hike and it was a learning experience setting up photos with waypoints. Although I don't fully understand the complete purpose of setting them up other than giving me a reference as to the distance from one to the other.   
Just one more question, I know I've read it on one of your threads but not sure where. I made the mistake of doing a separate install after I did the Southeast map this morning and it seemed to overwrite the Southeast so if I want to load separate maps (since the Southeast was actually over 4gb but I eliminated some of Delaware to keep it under the 4gb limit) how should the renaming of the "gmapsupp" be done in my Garmin folder of the SD card to insure that I keep the earlier map as well as load the new one and the device will recognize them all? Is there a limit to the no. of characters as well as using spaces or caps?

[Boyd]

I hardly think that 1500 map segments would be considered a small amount when it limited to 3500 segments to start with.

I can understand that. But I don't think Garmin cares how many segments their DVD map products contain. Instead, I think their goal was to keep the size of each individual sector small enough that an old device with small internal memory could still make good use of the map.

[Stingingfork]

I'm not sure I understand their rationale on providing the same topo but with such a large segment difference based on their different format (i.e. DVD vs Download)  but whatever floats their boat, I'll just keep that in mind if I'm ever in the market for another Garmin map. Thanks for your feedback!