Single eyed, simple telescopes used primarily for nature observations are called spotting Scopes. The smaller ones provide fixed magnification, can fit to pockets or small bags, and can perform well during hiking. The more advanced models are equipped with zoom eyepieces, provide magnification generally between 15-65x. Above 20x it is recommended to use a tripod. All of the spotting scopes have standard photo thread. The bigger ones are preferred by hunters, birders or hikers.