Align to grid with large maps

I was trying to upload this map ( <a href="http://m.flickr.com/#/photos/diabloazul/3281144163/sizes/in/photostream/" rel="nofollow">http://m.flickr.com/#/photos/diabloazul/3281144163/sizes/in/photostream/</a>) instead of doing each encounter on a separate map. When I use the align to grid tool then move the map only half of the grid is lined up while the other half is off. Anyone have any suggestions? Thanks.

If you look in the rooms you can see the tiles. If you use the ruler tool you can see that they line up. If I use the align tool in the top right corner then that will be lined up fine but if you look at the rest of the map it's off. It's a problem I have with every large map. Half will line up but half wont.

I suppose that it is because it is not really scaled to 70px. If you are off, by even a very slight distance, it won't be visible in the first squares, but as the error adds itself, it shall be visible on the last squares. For exemple, if you are off by one pixel every three squares, it won't be visible at the beginning, but 60 squares away (if the map is that big), you are off by 20 pixels, almost a third of a square.

The bigger the map, the more that even a single pixel of misalignment will affect the map.

I was hoping there was some sweet feature that would scale it properly for you but oh well. Is there an easy way to know what I should set the dimension to? Thanks for the feedback.

Math. Figure out how many pixels square each grid is and do the math to adjust it to 70px per square by counting how many squares there are across and down.

I tried to rescale it at 70px/square (it is originally at 60px/square). I made a 7560x5040 pixels map. It aligns itself well, when shifted to fit the grid.

Cool thanks. I'm pretty new to this stuff so the help is appreciated.

I no longer use the snap to grid, it is much more versatile to turn it off. Of course this only works on maps that have a grid printed on them, as the examples below. I haven't had any problems with it so far. If you were playing in a RL game with minis, you wouldn't have snap to grid on your battle mat.

I have struggled at times with the maps. What I found helps is to make the map rediculously large. Then I follow the align to grid guidelines. Sometimes it still does not line up completely correctly. When that occurs I hold alt to prevent the map from snapping to grid and I move the map around a little bit to line up the grid in other areas of the map. It works to keep the 'local' sections of the map lined up even if the long distance sections are not. - Gauss

I wish more maps would be made without grids. =/

Another way to do it effectively is to trim the map down to exact squares, by eliminating any half squares along the edges, then, assuming the map you're using is accurately gridded, you can simply count up the size by counting the grid, say 30 x 48, then resize the page grid to 30 X 48, pull the map in and stretch it out to the exact edge of the page and the Grid will be matched up. This will always work, if the map you start with has an accurate grid. In my post above where I show some examples, I can, if I want get those grids to line up perfectly using the method here.