Besides file size, what are the downsides to making a large dimension map?

[swiss]

size it according to it's use.

That's a good idea. Assuming my map didn't suck, I would like to print it out and put it on a wall. So something close to 4 feet x 3 feet (or maybe a different ratio).

That being said, based on another user's comments, I think I'm going to mess around with smaller maps first to get a hold of the basics. I've been using vector applications so I have a lot to learn in Photoshop

[swiss]

Mouse - I stumbled across some of your textures and it made me think of another question. Do you give any consideration for trying to keep textures and objects all within a range of the same Pixels Per Inch? For example: if I made a map of 300 PPI, would that limit a lot of existing textures out there I could use because they were a lower PPI?

[Mouse]

I'm not sure I really understand - especially since I don't have PS, but I presume that if the texture is 2500 px square, then it will open in your map at 2500 px square, and cover whatever area of your map represents 2500 px square.

I think, though you have temporarily muddled me up (), ppi is a bit irrelevant when opening one graphic up inside another. Its the actual size that matters. A texture that is only 1250 px square will only cover the corresponding 1250 px square space on your map.

I think ppi is only important when it comes to printing things as hard copy. Then its terribly important because it affects the size and sharpness of your printed image.

EDIT: if you want to copy some of the textures in my albums they are free to use, but I would recommend the ones in the Free Textures album rather than the ones in the Room 1024 album, since as the name suggests the ones in Room 1024 are only 1024 px square - specifically for CC3 users, whereas the others are all quite a lot larger than that

[swiss]

ppi is a bit irrelevant when opening one graphic up inside another. Its the actual size that matters. A texture that is only 1250 px square will only cover the corresponding 1250 px square space on your map.

Ahh, that helps. I was thinking about it the wrong way. Thank you

[mat_r]

Mouse is right. For the compatibility of digital images it is not really relevant. Be aware that ppi and dpi are two similar but different things. However both are really just conversion rates that tell us how big the physical dimensions of an image are going to be (on a monitor or after printing), since there is no standardized size for a "pixel".

Also, the "dpi-part" is something that you can easily change. That won't affect the pixel dimensions of your image whatsoever and you will not even see a difference at first. All it really does, is that the printer interprets your file a little differently and prints it bigger or smaller.

[Redrobes]

I agree with a lot of whats being said here. Just to clarify a few points - for the projection its normal to have a bitmap 2:1 i.e. twice width than height since the earth and planets are global and if you use a Mercator projection then you normally have +/- 90 degrees in the virtical direction but +/- 180 degrees in the horizontal. So thats why the projection can make a different to the aspect ratio. For other projections then its not so important that its 2:1.

For the scaling I agree with the font readability. Theres a lot of technical stuff in my tutorial about DPI, scaling and other stuff here:
https://www.cartographersguild.com/s...ead.php?t=2596

[ladiestorm]

Going back to your original question, besides file size, there are other things to consider when making a larger map, especially the size you are talking about.

Now some of the issues I'm bringing up, may not apply to your mapping, it really depends on what type of medium you are using to map with. Now if you are hand drawing your maps, most of these issues won't apply. But if you are making digital maps like most of us, then you are using some kind of program to do so, i.e. - photoshop, gimp, kriter, cc3+, FM8 (did I miss one?). So here are some issues you may come across:

1. Scale - Working on a map the size you mentioned, keeping your scale consistent can be a real problem. On a really large map, you won't be able to see the whole map in your monitor at the same time, you'll have to work on your map in small intervals. So keeping the mountains (for example), or your forests, on the same scale is extremely difficult. Inconsistent scaling on a map can really throw off the look of it, and it's almost impossible not to notice. Believe me, when I first started, I had a real scaling issues (sometimes I still do!), and I've noticed, at least for me, the bigger the map, the harder it is to keep it to scale.

2. Pixellation - This may be more of a problem for us cc3+ users, but I think photoshop's brushes and textures are similar enough to our bitmap fills that the issue could still exist. When you are working on an extremely large map, you have to stretch every stroke, brush, texture etc to fit that larger canvas. This is where dpi and ppi play a factor (I think). If the resolution isn't high enough on the texture you are using, then when you go to print out your map ( or post it here for viewing), it's going to come out pixellated (or blurry), because the texture just can't handle the massive size of the map. The opposite of this is what I call busy noise. If you are keeping your scale relatively small on such a massive map, then you have a LOT of space to fill. And when you try to fill all of that space, it can start to look a little busy, or cluttered. There would be SO MUCH detail in your map, that the viewer is overwhelmed. That also detracts from the overall look of the map.

3. Placement - it is so easy to get lost in a huge map. Because you can't see your whole map at once, you have to work on it section by section. It's hard to keep track of things that way. You could end up with mountain ranges that don't look natural, because of the way you placed them, in conjunction with everything else.

Working on smaller maps, at least in the beginning, allows you to see all (or most) of your map at once. This allows you to gauge your details better, keep your scale consistent, and it overall looks cleaner, because you aren't having to stretch so much.

[Redrobes]

All of those issues are issues with the app and textures that is making the map not a problem with the resolution of the image being used. Your app should be able to show the whole image and also manage the scaling of the parts being added to it. Your making the assumption that you must view the image at 1 pixel image = 1 pixel on screen when drawing which is rarely true and certainly not necessary. The ability to navigate that image is the apps problem not a problem of image resolution.

Perhaps the biggest problem with using large pixel bitmaps is that many mapping apps dont handle them well.