on high resolution 1280x1024 SC reacts a little bit sluggish

[masu]

especially if you want to move or zoom the image 

[mouser]

make sure you check these options that can affect speed:


if your image has objects/frame, then check the objects tab in preferences for another option that can effect speed:


objects+frames can really slow down rendering. if you are sure you are done moving them arround you can "merge" them into the picture from the Objects menu which will return you to the speed for a normal image but you wont be able to remove them or move them any more.