How to view pictures from usb without uploading it to iphoto

Im new to macbook pro from pc...i used to view photos from usb or sd card without importing it to computer...all i have to do is insert the sd thru usb and double click on one of the pictures and click the arrow to view the next picture.when im done i simply eject it.but in macbook pro (mountain lion)i have to double click the thumbnail and close it and double click another thumb nail to view another picture using the preview.i dont want some photos to be imported to iphoto just to view by slideshow.thanks