In reply to Enty:
Adam's right. Just re-size the original to around 1500 pixels wide then, as long as the file itself is then less than 250K then you will get the pop out effect that I got with the St Leger shot.
Resize photos - if you are making panoramas then you must be using software that can resize photos. Look around the software a bit, use the manual maybe, if there is one?
Alan