Scanning and calibrating paper maps for Oziexplorer

Submitted: Saturday, Apr 19, 2008 at 22:46
ThreadID: 56790 Views:4880 Replies:11 FollowUps:10
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Evening all,

I'm after a few tips regarding the scanning of paper maps to digital format with the intention of calibrating them and using them on OziExplorerCE (PDA).

I've done quite a few - started out photocopying them, then scanning at A4. I had a few grid lines out by a fair margin and a few roads/tracks wouldn't align.

Plan B - photocopying the maps but reducing the size from A3 to A4, then scanning them. The idea being less scanning required - hence less errors. This 'sort' of worked but some scans ended up being approx 1% out - ie gridlines and tracks wouldn't match up.

Has anyone successfully scanned large paper maps and had a seamless end product? I'm still looking out for a large scanner at a printing business that could do a map in one pass - but so far I've only found A3 and the cost is prohibitive.

Any suggestions appreciated!

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Reply By: Zebra400 - Saturday, Apr 19, 2008 at 22:50

Saturday, Apr 19, 2008 at 22:50
I found the best way was to scan A4 sections, calibrate them, then use Ozi Mapmerge to join them up. I did this for a paper Rooftop map and it worked fine.

Takes a bit of time, but the end result is great.
AnswerID: 299366

Follow Up By: Member - Tim - Stratford (VIC) - Saturday, Apr 19, 2008 at 22:54

Saturday, Apr 19, 2008 at 22:54
Thanks Zebra,

I'll give it a try. I think I still have the digital sections I scanned - otherwise it's back to the photocopier!

FollowupID: 565542

Reply By: Member - joc45 (WA) - Saturday, Apr 19, 2008 at 23:15

Saturday, Apr 19, 2008 at 23:15
Hi Tim, I haven't tried OziMapmerge, but I did some A1-sized maps a few years back.
I tried my Canon Photostitch software, which merges photos, and it got totally confused, so gave up on that. I ended up using a conventional photo-editor program, making each scanned A4 page overlap, and putting a faded edge on each page. Using the rotate function, I managed to align each page quite well, with minimum error. An A1 map used about 10 A4 scanned pages. I made sure that all 10 were on the final page and aligned before merging the lot.
Geez, it took some nights though!
AnswerID: 299369

Reply By: The Explorer - Sunday, Apr 20, 2008 at 02:23

Sunday, Apr 20, 2008 at 02:23

One method is describe here

Scanning Maps

Before proceeding too far would suggest seeking out other options as it can be very time consuming to get good result. Maps of Vic, ready to go with Oziexplorer are available free from the gps australia forum...and other maps for various areas are available at cost, see exploroz shop. Suppose it depends how much spare time you have and if the map/maps you want are already done.

If the map you want is not around in digital fromat next best option is to get it scanned properly. You can get full size maps scanned in Perth for ~$30 a pop, suspect other cities would have similar services. Sure beats stuffing around for hours at home for maybe second rate result.

I sent one final shout after him to stick to the track, to which he replied “All right,” That was the last ever seen of Gibson - E Giles 23 April 1874

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AnswerID: 299382

Reply By: chocolate teapot - Sunday, Apr 20, 2008 at 07:02

Sunday, Apr 20, 2008 at 07:02
Hi Tim

like jock45 I scanned the maps in a4 chunks and merged them using - bit of a fiddle and a few brain spasms - but it works.

You end up with a large digital map you then align in the normal way in a number of points with ozi.

Please don't be offended but I would suggest that your way would introduce too many errors - remember that when you photocopy there are al sorts of distortions from each stage - the optics, the electronics and then putting them all back together - the merge is pretty simple with.

Having done it I would suggest that if you can buy the maps of interest in digital form at a reasonable price that is the way I would go.

Overall assessment of my method - possible but difficult and time consuming.

Hope this helps

AnswerID: 299388

Follow Up By: Member - joc45 (WA) - Sunday, Apr 20, 2008 at 11:20

Sunday, Apr 20, 2008 at 11:20
Hi Choc Teapot,
Yes, I found that the edges of the scan were the worst for distortion, usually where the map curls up on the edge of the scanner. So I used a smaller part of the scan, discarding the edges, and fuzzing the new edges. This way, the overlaps of the individual maps looked seamless.
I eventually got mine pretty error-free, with usually only about a mm error on the merges. Took some trial and error, tho.
Panavue program stitches them well, but it costs. The trial version leaves a "Panavue" watermark on the image.
But if, as Greg (Explorer) says, you can get an A1 map scanned for $30, this looks like a better way than spending an evening per map scanning the damn thing.
FollowupID: 565579

Reply By: Member - Tim - Stratford (VIC) - Sunday, Apr 20, 2008 at 08:11

Sunday, Apr 20, 2008 at 08:11
Thanks for all the replies. The maps I'm after aren't available as digital maps yet, hence my attempt - and frustration :-)

The A1 scanner sounds like the go. I might have to pack my maps next time I'm off to the big smoke, lol.

Thanks again,

AnswerID: 299391

Reply By: Member - John and Val W (ACT) - Sunday, Apr 20, 2008 at 09:03

Sunday, Apr 20, 2008 at 09:03
We have had some success taking a digital photo of maps. Depending on the size of the map and the resolution of your camera you can get the map in fewer sections than is possible with a scanner. But you have to place the camera squarely above the map otherwise there is distortion.
J and V
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AnswerID: 299397

Reply By: Mr Pointyhead - Sunday, Apr 20, 2008 at 09:42

Sunday, Apr 20, 2008 at 09:42
Try and find somewhere that has a A0 flatbed scanner. I found a print shop in Melbourne CBD that has one and will scan a A0 map for about $40 - $50. Not that cheap, but it save mucking around with trying to stitch together small pieces, and you get it right first time.

These days I find good digital mapping is available for most areas, so it is only the occasional specialised map I need to get done.
AnswerID: 299402

Reply By: Member - Roscoe ET (QLD) - Sunday, Apr 20, 2008 at 09:49

Sunday, Apr 20, 2008 at 09:49
Hi Tim,

I take it that the end result of what you are doing is to use the maps on a laptop with GPS input using OziExplorer?

If this is the case it seems to me you are going about this in a laborious way with all this photocopying and scanning.

Have you thought about purchasing the Natmap Raster Premuim disc. These maps are exact digital copies Geoscience Australia's Natmap topographic maps and can be used for real-time navigation with GPS.

The OziExplorer program will allow you to work with these digital maps.

I have both the Natmap Raster Premium disc and the OziExplorer program. I haven't seriously created anything yet just had a bit of a play around but I'm pretty sure that what you are trying to do can be achieved by using Natmap digital mapping. I'm sure you won't have any issues with grid lines etc misaligning.

AnswerID: 299403

Follow Up By: Member - joc45 (WA) - Sunday, Apr 20, 2008 at 11:29

Sunday, Apr 20, 2008 at 11:29
Hi Roscoe,
it depends on what you want and what's available. While a lot of hi-res maps are available commercially (or free) for eastern states, in WA, you can buy the digitized DOLA 50k maps ok (thanks to Explorer), but the excellent CALM 50k maps of the SW of WA are only available in paper form, not digitized (or were when last I checked).
I spent many weeks of nights scanning my large collection of CALM maps, but it was worth it.
FollowupID: 565581

Follow Up By: Member - Roscoe ET (QLD) - Sunday, Apr 20, 2008 at 13:47

Sunday, Apr 20, 2008 at 13:47

The Rasta mapping I have was last updated on 06.03.07. I take it from what you are saying the CALM maps show more or better detail than the topographic Raster map?

Mate I'm not disputing what you're saying I'm just curious as to the difference between the two as the Raster map does show extensive detail. I've been printing off hard copies of areas that I have travelled and used them last year when I was over your way.

As an example I went across from Mt Augustus to Paraburdoo and it was spot on I knew exactly where I was at all times.

Eventually I want to get a laptop with GPS software and I was going to use Raster maps but if there's something better then I'd consider it.

Surely there's got to be a better way than spending hours of scanning in this day and age but I suppose in due course more and more mapping will become available on disc.
FollowupID: 565593

Follow Up By: Member - joc45 (WA) - Sunday, Apr 20, 2008 at 23:25

Sunday, Apr 20, 2008 at 23:25
Hi Roscoe,
I'm assuming you are referring to the Natmap 250 Mosaic map. My version is about 3 years old. This has pretty good detail, but the 50k CALM maps of the SW show every fire trail, tree blaze, etc, which the Natmap, or even the 50k DOLA maps don't show.
But I wouldn't be using a 50k map out in the country you describe.
Actually, I was using the 250k Natmap driving from Minilya to Mt Augustus (WA), and in one place, for several kilometres, the map showed the road going where it had never gone before. Thought it might have shown the old road, but there were thick trees where the map showed - never ever was a road there.
Interestingly, I have old army maps of the Nullarbor dating around 1960 which are more accurate for some tracks than the current Natmap 250k!
FollowupID: 565741

Follow Up By: Member - Roscoe ET (QLD) - Monday, Apr 21, 2008 at 09:09

Monday, Apr 21, 2008 at 09:09
Thanks for that Gerry had a feeling the extra detail might have been fire trails and the like. Those old army maps are pretty good if you can get hold of them.

Same with the marine ones from the navy, a friend of mine in Gladstone got hold of one for the area out off the coast there, showed a few drop offs and small reefs that weren't on the normal chart...suffice to say we kept them to ourselves!!!
FollowupID: 565766

Reply By: Trev (SA) - Sunday, Apr 20, 2008 at 16:39

Sunday, Apr 20, 2008 at 16:39
The Ozi Mapmerge utility is the only way to go. Tried all the stitching programs under the sun with no success.

MapMerge does not stitch based on the picture but rather based on the calibration co-ords of each individual calibrated map you are trying to merge.

You can download the utility from the Ozi website (look under "optional extras")

AnswerID: 299453

Follow Up By: Member - Tim - Stratford (VIC) - Sunday, Apr 20, 2008 at 16:51

Sunday, Apr 20, 2008 at 16:51
Thanks Trev,

I'll give it a go.

FollowupID: 565621

Reply By: Member - Jim R (ACT) - Monday, Apr 21, 2008 at 09:22

Monday, Apr 21, 2008 at 09:22
For what its worth, I have tried most of the approaches described in previous responses with varying degrees of success. MapMerge is a very ggod tool but the end result depends VERY heavily on the accuracy with which the component maps have been calibrated.

The best results I have achieved, which really did result in a seamless join between portions was to use a product called Panvue Image Assembler which was not terribly expensive but gives EXCELLENT results. It readily takes account of slight misalighnments in your scanning (a problem with most normal image editing software) and can even cope with images of different scales.

One important thing is to convert any resulting image (which can be VERY large) into OZF3 format so that it will page into memory with OziExplorer rather than try and load in totality as many image formats do.
AnswerID: 299587

Follow Up By: Member - joc45 (WA) - Monday, Apr 21, 2008 at 12:48

Monday, Apr 21, 2008 at 12:48
Hi Jim,
Yes, I've tried the trial version of Panavue, and it works well, warping the image slightly if necessary to match the adjoining page to be merged, so that the end result is a seamless join. Would recommend it.
My Canon Photostich software which came with my digital camera does a similar thing (in fact it does a brilliant job in merging photos, including warping and shifting the colours to match) but it seemed to get totally confused using maps with just a few colours. The end result was a mangled mess!
FollowupID: 565794

Follow Up By: Member - Jim R (ACT) - Monday, Apr 21, 2008 at 14:10

Monday, Apr 21, 2008 at 14:10

The thing I like about panavue was the ability to help it out by desgnating points on overlapping maps that coincide. By doing this I have found all joins to be totally invisible.

FollowupID: 565806

Follow Up By: Member - joc45 (WA) - Monday, Apr 21, 2008 at 22:54

Monday, Apr 21, 2008 at 22:54
Yes, even Panavue gets it wrong occasionally, but being able to designate points that coincide allows Panavue to pull the scans together properly. Something that Canon's Photostitch couldn't do.
FollowupID: 565886

Reply By: Member - Tim - Stratford (VIC) - Thursday, Apr 24, 2008 at 16:04

Thursday, Apr 24, 2008 at 16:04
Thanks again to all who answered,

I've just got back from our annual Boy's Trip - one of the guys on the trip has access to an A1 scanner at his work - I'm in the process of arranging all my maps to be scanned in one pass!

No more merging problems......hopefully.

Thanks again,

AnswerID: 300269

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