Hi all,
I need some more help on working with scale and the size of my documents (looking at making a new map with more accurate scaling).

MY STORY

The current map that I have been working on over the last year or so (on and off) has been at a fairly distant scale (more than one continent in the entire document):
Click image for larger version. 

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If you view the attached image, you will notice that entire forests are represented by one to two inches when viewed in Print size. (Note: yes I know everything isn't exactly to scale, and yes I know geographically rivers, etc, aren't properly placed... This was the first map I ever did - ever - and prior to research).
The text itself is actually rather pixelated when you zoom in to 100% (well pretty much everything is pixelated at 100%), and is completely unreadable when Photoshop is set to View Print Size. I am using Macbook Pro 15.4" laptop with screen resolution 1680x1050 (which makes my screen ppi 128.65 - set in Photoshop).

Now the problem I have is at this scale its really hard for me to depict where cities, towns are - let alone smaller places like hamets and farms. As the map will be based upon my novels set in the world of Ervirath, this is a big problem as many of the scenes occur in smaller "locations".

I started doing some calculations, which also cause some issues. I decided I'd break down my map to focus on individual continents. My point of scale I was going to work off of was the size of individual tree's in my forests. The attached image below is an example of what my forests look like:
Click image for larger version. 

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Going with the basic estimate that a standard tree has a canopy width of 20 feet, I have scaled my trees in size to determine how many pixels would represent a single Kilometer or Mile. There are 3280 ft in 1 KM, and 2.6KM is equal to 1 Mile.

If I scale the tree canopy to 30% (100% being massive - note the 30% is more for my reference and not needed for the maths), a single tree has a pixel length of 10px. So 10px is equal to 20ft. Therefore 1KM is 1640px and 1 Mile is 4264px!

10 to 12 miles is about the maximum extent of 'a good day's walk', two or three miles is the extent of a daily commute (you don't want to tire yourself out before you get to the fields) (according to Elfwood). Just to represent an equivalent area in a map for one days worth of travel the map would be approximately 42 000px wide! Obviously this isn't appropriate (my computer couldn't handle a file that big for sure).

If I scale the tree's down to 5% (approximate size of trees in my original map), then 2px is equivalent to 20 feet. That means 1px is equal to 10 feet > 328pixels is equal to 1KM or 853pixels is 1 Mile. Then a day's worth of travel would be 8500 pixels. My computer can handle files at that size... but again my problem of the map being too distant....

My other map I did rescale the image pixels (keeping resolution as its due for print at 300 ppi) from 9000 to 15,000. This made the print size much more acceptable, but the scaling also made everything "blurry".

I should point out:
  • I use Photoshop CS6.
  • I have a Macbook Pro 15.4" with 2.66 GHZ Intel Core i7 with 8GB 1067MHz DDR3 Ram.
  • I do have access to a desktop (rough specs is 2 graphics cards, 16 gig ram) - just not as regularly as my laptop. It's a lot more powerful however.
  • I plan to print my map (so need 300dpi) as a large poster over 1 meter by 1 meter in size - depending on map was thinking the size of the actual study wall even.


I have come to the opinion that I don't think I can portray the entire document with high levels of details. Ideally I would like to portray my land with details down to the houses themselves. I don't particularly want to break up my map into multiple documents (tiling it so to say). This can get quite unmanageable fairly fast.

SOME REQUEST FOR ADVICE
If you can't help me with suggestions for my problem (above), then could you perhaps mention what size documents that you have worked with in the past please so I can get some ideas.

Thanks