Originally Posted by Bowenp
Having upload problems but here is one (the only one a can upload without it failing)
You need to downsize your photos first. ;-)
When you use the paperclip icon to attach an image to a post, you'll see the maximum allowed sizes for each file type on the Manage Attachments screen that comes up (where you browse for a photo and upload it).
For JPEG image files, to stay within those maximum allowed sizes, you'll need to make sure that images are downsized so that the longest side is no longer than 1024 pixels, and the file size is no larger than 253.9KB.
If you exceed those maximum allowed sizes for either dimensions or file size, the forums software will attempt to make the image "fit" anyway by downsizing and recompressing the image. But, that will result in softer images because the compression algorithms leave something to be desired, and the forums software will also strip out the EXIF information from the image metadata (so that you can't see the camera settings that were used). I can tell that happened image attached to that post (the forums software recompressed it because it exceeded the maximum allowed sizes).
But, sometimes the forums software will fail to downsize and recompress an image so that it fits (because of the preset values being used by the compression software libraries) and the upload will fail (which is probably what happened with your other attempts). I sometimes see that when members try to upload a full size image from their camera.
So, for more than one reason (including showing better quality images), it's a good idea to resize your images so that they are within the maximum allowed sizes for both dimensions and file size before you try to attach them to a post here. With most image editors, if you resize an image so that the longest side is around 800 pixels, then save it using a JPEG Quality Setting of around 80% (or 8 if your software uses a 1 to 10/12 type scale), that should keep it so that it's within the maximum allowed file size of 260,000 bytes (approx. 253.9KB)