How can I choose the zoom level for my map?

Question

According to both Notch's Twitter (no link) and the wiki, maps have some kind of settable zoom:

A zoom level, which will somehow be decided at the time the map is created.

I have no idea how to set this. Anyone know?

EDIT: based on fjdumont's answer, how is it calculated? Is there anything I can do (such as craft it in a certain place) to give it a zoom level close to what I want?

Answer 1

You can zoom map files, but you have to do it by editing your NBT files. This answer is thanks to this redditor:

If you're willing to dive deep into the NBT files, you can adjust the map's center and zoom levels. Just don't screw with dimension (locks the map) or width/height — it doesn't work. The files are under <map-name>/Data/map_X.dat, where X is the map number.

You'll need to use an editor like NBTEdit to edit the files.

Answer 2

From version 1.4, you can zoom maps in game, as the whole process of map-making is changed:

1. First, a blank map is created
   
   This blank map will not start recording immediately, as maps previously did.

2. The blank map can be activated by right clicking it, which turns it into a map at the most zoomed in level (1 px/1 block)

3. To scale the map by a factor of two, take the map and recraft it as follows:
   Each time this is done the map will scale out, so from 1px -> 1 block, to 1 px -> 4 blocks, to 1 px -> 16 blocks and so on. This can be done a maximum of 5 times. Maps cannot be scaled back in, only out.

Answer 3

Looks like yes, this is the work of a mod. Here's how you can do it:

1. Download NBTedit from here
2. Unzip the ZIP file
3. Run NBTedit
4. Click File -> Open
5. Navigate to your save folder
6. Go to the "Data" folder
7. Open the map_0 file. If its not map_0 you want to edit, choose the right one.
8. Expand the "data: 7 entries" branch
9. Change the "scale" value to the one you want. I chose 1, but it can be anything.

Answer 4

I have made a program specifically for map item files. You can find it here http://sourceforge.net/projects/mapitemedit/

You can edit your zoom level, map coordinates, even change the picture data.

Answer 5

When crafting a zoomed out map with eight pieces of paper, shift-clicking on the output map in the crafting table does not make a newly scaled map

in the bug section of the wiki

http://www.minecraftwiki.net/wiki/Map_(item)

Answer 6

The zoom level is calculated depending on the time you craft it. You can not set/reset or choose it yourself.

Answer 7

first of all make a map, use it so you have a really zoomed in map, then put it in the center of the crafting table, surround it by eight pieces of paper and then normal click it! if you shift click it, it will not zoom out there is a bug to where it will not zoom out if you shift click so normal click and there you go