HOG map maker beginner

jbanetman

New member
Hi all. I am attempting to learn HOG DEM map making. I noticed on the GIS Data Depot site(I am following the tutorial that was made in 2003, and except for a few differences due to updated programs it worked ok), that there are 10 meter 24K DEMs along with the 30 meter DEMs the tutorial used. Is it ok to use the 10 meter DEMs, or does HOG expect the DEMs to be 30 meter and no other size? The Bay Shore west, NY DEM I worked with in the tutorial came out ok with the Tiger lines, but didn't have very much elevation, a maximum of 8 meters, where the Microdem program said the max should be 23 meters? I used the 10 meter DEM so was that the problem? If anyone can help that would be great.
 
Low elevation?

Sounds like you did the convert feet to metres, latest version of microdem is already in metres not feet, so you don't have to convert it, if you do you get very low elevation. I tried about a dozen times before I spotted it!
If you haven't noticed, it also now saves as TGA, you don't have to convert in an external program.

The tutorial is a little bit out of date for the latest version of microdem.

10m dems should be OK, not tried it myself though as there aren't any available for the UK............
 
That could be it, I was following the tutorial and assumed I needed to do the meters/feet convert. I will try again without doing any conversion, and I'll check if Microdem saves in TGA, that would mean I don't need to do Irfanview resave as TGA. Would make the process simpler. I assumed the 10 meter DEM just had 3 times the point grid as the 30 meter, and would be show more detail. So I'll try it again hopefully going straight from Microdem to HOG. Thanks for the hint.:)
 
Don't get your DEM from the GIS site, get them from the Seamless Server. You have more contol on what you want to download. I can guide you through the process if need be.
 
Now see I use GIS data because I find that easier and more controllable ;)

You can use either 10 meter or 30 meter data, but NOT a mix of both. Often on large routes you have no option but to download a mix in which case you must convert. If you need more info on converting post back...

Andy :)
 
Don't get your DEM from the GIS site, get them from the Seamless Server. You have more contol on what you want to download. I can guide you through the process if need be.

What is the Seamless Server? And how do you get DEMs there? I'm just experimenting and learning right now, so any help with how-to is welcome. The tutorial I read didn't mention anything about combining DEMS for covering a larger area than one DEM, so I will need some help with that too if you would.
 
Now see I use GIS data because I find that easier and more controllable ;)

You can use either 10 meter or 30 meter data, but NOT a mix of both. Often on large routes you have no option but to download a mix in which case you must convert. If you need more info on converting post back...

Andy :)

Hmm, that's another thing the old tutorial didn't go over, how to convert between 10/30 meter DEM, I did notice some areas only have one or the other.
 
The old tutorial had me get the full version of Microdem, but the site did say there was an updated version. So I only have the older full version, not the latest update. Should I get that? It would be appreciated if there was help on how the process has changed with the newest Microdem.
 
The old tutorial had me get the full version of Microdem, but the site did say there was an updated version. So I only have the older full version, not the latest update. Should I get that? It would be appreciated if there was help on how the process has changed with the newest Microdem.


What is the build number of the microdem you have now?
 
Long post, several answers in one go:

MicroDem versions: It doesn't matter which currently available version you get, it won't be the same as the tute. Lat time I installed on a new computer I looked hard for a source of the tute version simply because I was accustomed to using it. I couldn't find a source.

GIS and Seamless: If you persist with the GIS data what you are downloading is 'Quads'. Quads cover a pretty small area, so to make a decent sized proto route you will need to combine several quads. I like big routes and some of mine have 50+ and IIRC one nudges up towards 100. 'Seamless' data on the other hand only needs one (large) download. I like Quads (cause I'm old, doddery, and stuck in the past) the younger set prefer seamless. In the end product it makes little difference.

Merging Dems: 'merging', which you will need if you persist with Quads.. About half way along the top M'Dem toolbar is a button with two horizontal arrows labelled 'In - Out'.

'In - Out' > Merge > DEMS > Pick Single > then just click successively on each Quad to be merged. I find the alternate 'Pick Multiple' option unreliable.

10m and 30m: When the tute was written it was all 30m data, so the option wasn't an issue. Now lots of 10m data is available. If your route has all one or the other use it. Often though some Quads will only be available as one or the other. 10m DEM is more accurate, but you are making a simulated train route on a computer, not planning national defense strategies. 30m DEM is plenty good enough for Trainz, the data packs are smaller and you can merge much bigger maps in M'Dem using 30m than you can 10m. So I opt for 30m wherever it is still available.

If you are stuck with both though, merge all the 30m and save. Merge all the 10m and save. It does not matter if the quads are not adjoining. Now open each merge in succession and from the top toolbar File > Save DEM > DTED > accept defaults and save. Do the same for the other merge. Now merge the DTEDs. Save that merge with no options and you will revert to the format used by HOG.

With a big route you will get to the point where M'Dem can't cope with the merge. You will get there quicker with 10m Data. At that point you need to start making multiple routes and merging in Trainz. We'll cover that when you get there :)

I need coffee...

Andy ;)
 
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Thanks Dermmy, I'll digest all that. As for which Microdem I've got, its build 2011.5.12.1 made on 4/10/2011. And there's no option to save as TGA directly, so using BMP then Irfan to convert to TGA.
 
I redid the tutorial, and didn't convert to feet, and the DEM came out much better, a lot higher range of elevation, so got that sorted. On to checking out the Seamless Server, I may like that better, I'll see.:)
 
A question about the baseheight entry, the tutorial said if the DEM didn't have a sealevel, meaning only land, not land and coast, I should put in the baseheight number. I didn't quite understand where to get that value from.
 
Dermmy, LOL. You're old and doddery? So you call younger guys 'Whippersnappers' I guess? BTW, I'm 53 so maybe I'm edging toward old and doddery?:hehe:
 
A question about the baseheight entry, the tutorial said if the DEM didn't have a sealevel, meaning only land, not land and coast, I should put in the baseheight number. I didn't quite understand where to get that value from.

Click the info button it will give you the z range something like 0 to 500m
or if its not at sea level say 400 to 1000.
So in that case you would use 400 for the base level and 1000 for the highest point.
 
Thank you, Andy for the very long post. I found this information very useful and have copied the text to my important Trainz info file. :)

John
 
I looked at the Seamless Server, and figured out how to bring up the seamless map. I zoomed into an area and went to download - these are NED 1 arc, or NED 1/3 arc files. I downloaded the NED 1 arc(30 meter) and tried to load it into Microdem, and it said that the file was an unknown/ unsupported type?
 
I found the answer to the 'Unsupported/Unknown file' in Microdem when trying to read the NED 1 arc and NED 1/3 arc files. On the Seamless server, when you have zoomed in and selected your rectangular area, when the download box comes up, click the Modify Download Request and change the zip file content from the default type to the Bil-16int type, and Microdem will load it.:)
 
Hi, all. Could someone help me with this question, please? I'm currently experimenting with the USGS Seamless server, and can download my rectangular area, and correctly process the area in Microdem to get my BMP of the terrain. But I'm scratching my head on how to do the Tiger overlay properly for the rectangular area. I did the rectangular area, and tried to overlay the county Tiger line file. It did overlay ok, (Roads, etc seemed in the correct places), but the overlay left straight lines going across the image from left to right. So I don't know why it did that, the GIS data depot method of quads with the Tiger file didn't have that problem. :confused: I would prefer the Seamless server, so I can download and then do the whole area at one time.
 
BTW, forgot to mention that I didn't see how to get the Tiger line file direct from the Seamless server download, where I got the rectangular area Terrain from. So I used the GIS data depot Tiger file for that county of the state area I was working with. Could that be the problem, maybe I missed where to get the Tiger file for the area, from the Seamless server?
 
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