I can't export 4500x2500mm image with 300 or even 150 dpi. Need to do it with only 96 dpi.
I'm using Acrobat X Pro.
What is the limit and why is there limit?
Photoshop CS and later can work with documents up to 300,000 pixels in each dimension, but it's limited by RAM and when saving a document you have filesize limits due to the bit depth of the headers:
PSD = 2GB
PSB = 4GB
Tiff = 4GB
A Tiff file can in theory contain an image with a 4 billion pixel canvas dimension, but in practice it would exceed the filesize.