The problem with many free image hosts is that there is quite a high file size cut-off on image size (in kilobytes) so if you are trying to upload straight from your camera and the resultant images are in megabytes not kilobytes, then it is expected you will have problems.
Auction images need only be on average 50kbs in file size, not all page viewers have broadband, and to view a page with multiple images that run into megabytes can take ages, and often the buyer moves on to the next item !
Assuming you are using a modern digi camera, it needs to be set at web or basic for most if not all auction images, no point in taking a high resolution image to be displayed on a PC monitor, at best resolution is 100dpi, so a high resoution image is not only wasted on t'internet, but also creates a large file size in KB's, hence the upload problem.
Its a simple process to crop to size (say 500 x 400 pixels) before upload, then you have control over the clarity, most images could do with a little sharpen after resize, and most sites that have the edit after upload function do not re sharpen, just resize.
So my advice would be to size the the preferred auction size before upload.
The solution is to edit your images prior to upload, aim for approx 50 kbs each and about 500 x 400 in pixels . Irfanview can do this for you (its a free download and used by millions for auction images) .then you should have no problem in uploading them to any image host.
Once you have created your auction images, why not try a free auction dedicated image host, where your uploaded images can either be integrated into the ebay sell item process with a few clicks, or better still create a nice auction template that is also integrated in the eBay sell item form with just a few clicks.
For a free auction imahe host, please visit my About Me page