1
vote
0answers
57 views

Whats an appropriate map projection for georeferencing aerial photos?

I have some aerial photos that were shot from directly overhead a 5x5 mile property. They were then mosaiced to create a continuous overhead tiff of the entire property. I am now going to ...
2
votes
1answer
134 views

How to find the projection of an image?

Instead of georeferencing the image and deforming it, I'm trying to find the projection used by the author of the image. I've got tens of these distribution maps to digitize. The idea is to avoid ...
0
votes
1answer
71 views

How to choose a coordinate reference system

I have a jpeg image of a reserve's layout and would like to use it to plot animals movements on i.e. GPS points. I have no idea which coordinate reference system to choose during the "georeferencing" ...
1
vote
1answer
64 views

Can I define a transformation between 2D and 3D in Geotools?

I'm using Geotools, and I need to convert coordinates between 2D and 3D coordinate reference systems. I recognize that there's no universally-correct way to do this: 2D -> 3D means "making up" a Z ...
1
vote
1answer
219 views

What is the coordinate system of this maritime natural gas field map?

The Israeli Ministry of Natural Infrastructure, Energy and Water Resources published a maritime map of the borders of a new natural gas field. The map is a part of a full license (PDF), a legal ...
3
votes
2answers
54 views

What is the closest CRS to “Meridiano de Greenwich”

I have a 1906 scanned map that I am trying to georeference in QGIS for Mac. The map has French and English lat-long, indicating them as either "Meridiano de Greenwich" or "Meridiano de Paris." I would ...
0
votes
2answers
142 views

Help, I have 10,000+ .shp files covering 3 UTM zones with unknown projections

I was handed a ton of property files with no projections attached but was told they are all in UTM zone 21S. Well once I merged them all together and projected them I realized that the data covers 3 ...
0
votes
1answer
633 views

Convert long/lat to indian grid system

how to convert lat/long coordinates to Indian Grid system? I've googled for a couple of days but didnt find the exact algorithm for this. and i got a link Indian Grid System. but i didnt get a picture ...
2
votes
1answer
430 views

How to align (georeference) images using QGIS?

I'm completely new to all this. I'm trying to make a map of Han dynasty-era China for a mod for a game called Crusader Kings 2. I've downloaded QGIS and Natural Earth 2, but I need this image to ...
0
votes
1answer
145 views

converting grid references to long/lat

If I import from a POST DB a set of points that are referenced by grid reference, will the long/lat decimal also be added to the file? or will I have to convert the points to long/lat myself? In ...
7
votes
2answers
489 views

How to Georeference Photos With No Spatial Reference?

I have about 100-200 field ground shot photos I would like to overlay in ArcGIS 10 that have no spatial information which I need to somehow develop using a photogrammetric formula. The camera was ...
3
votes
2answers
223 views

How to create georeferenced and projected data from hand-drawn map?

I am preparing datasets for students in a spatial statistics course for a module on spatial autoregressive models. We will use ArcGIS 10.1. The first dataset will correspond to a mythical ...
6
votes
2answers
5k views

Which coordinate system and projection shall I use for georeferencing google map image in ArcGIS?

I have saved Google Maps image (not Google Earth) of area at latlon(17.692437,83.218689) by some method in jpeg format. It is an exact snapshot of the Google Maps. Now I need to geo-reference it to ...
1
vote
1answer
139 views

Taking a 'custom' map and transforming its x/y co-ordinates to 'real' long/lat co-ordinates?

I was wondering if someone could help me out with a little project I'm working on. I'll try to describe what I'm trying to achieve - if it doesn't make sense, please let me know. I have in front of ...
3
votes
1answer
465 views

How to create aux.xml file?

after starting to use MOBAC to create offline background maps I found the aux.xml files very useful as QGIS automatically sets the CRS so this would be very useful for my colleagues with smaller GIS ...
4
votes
3answers
838 views

How do I specify a CRS for a fictional game map in QGIS?

I am about to start playing a steampunk RPG game called The Iron Realm, which uses a fictional world map. I have recently started using QGIS v1.7 and have no real experience with GIS sysstems. I have ...
5
votes
2answers
4k views

Convert x, y position in georeferenced image (with world file) to longitude, latitude?

What steps do I need to do in order to calculate longitude and latitude for a specific pixel in a georeferenced image? For example this image ...