Originally Posted by hunchermuncher
This is unrelated to Sigil, so the mods may move it to the mobi forum, where it's better suited, but, seriously? That image is HUGE. If you do the math, you'll see that you've made an image that's ~3 times as large as it needs to be. As in:
1,000 px times 1600 pix = 1,600,000 pixels, right?
1657px times 2500 px = 4,142,500 pixels, which is nearly 3 times the size. Remember that Amazon charges delivery fees for books, so you don't want to go bats with filesizes embedded inside the book. If you're the publisher, you could potentially be yanking $0.30 off of every sale with that extra-large cover size, or, worse, if the publisher is your client, you're costing them $0.30 or more on every single sale.
Hope this helps.