When choosing a magnifier it is important to select the lowest level of magnification you feel is comfortable to carry out the task you want to achieve.  Weaker magnifiers tend to be larger giving you a wider view. More powerful magnifiers are smaller and have to be held close to your eye and what you want to look at. With stronger magnifiers, which are smaller, you might not be able to see as much at once, you may only be able to read parts of words rather than whole words or sentences.

Magnification for some tasks can be achieved in a number of different ways e.g. watching TV could be achieved using a telescope or by simply decreasing the viewing distance.  Reading normal print on a page may be achieved with a dome magnifier or with a large print text.

People may have more than one magnifier which they use for different things e.g. a stand magnifier for doing a crossword and a hand-held to take out with them to read price labels.

It is very possible that you may want to combine magnification methods for the best results e.g using a magnifier and sitting closer to view an object.

The most important consideration is what you feel comfortable using.

For distance vision

Bringing the object closer or telescopic magnification are most appropriate.  Real image magnification could be carried out using a CCTV system. The only practical portable vision aid is a telescope other than moving closer to the object which is not always possible.  Telescopes or monoculars are viewed through one eye and binoculars using two eyes.  They can be used for tasks where you are not moving about e.g. going to the theatre or watching a football match.  Where it is a moving task such as seeing a bus number you would need to stand in one position to use the device.  Telescopes can be spectacle mounted or hand held and with some you can change the power for different viewing distances.  To view more details on the products available for distance vision see the sections on Telescopes and Binoculars in the Product Pages.

For near vision

The most common aid is the plus magnifier which makes the object appear closer – these can be hand-held, stand or spectacle mounted. Hand and stand magnifiers are designed to be used in addition to any spectacles or reading glasses prescribed by your optometrist. 
The hand-held magnifier is a familiar style to people and is relatively inexpensive and good for spotting tasks.  It can be difficult to keep the correct position over a longer period of time. Stand magnifiers maintain the distance between the eye and the task and are particularly useful if your hand is not steady. Usually a flat surface is needed to work on.  Both hand and stand magnifiers can have integral illumination which can aid vision.  Spectacle-mounted magnifiers are hands free and give the widest field-of-view as the lens is very close to the eye.  They are similar to an ordinary pair of spectacles in appearance. Clip-on versions are also available to be used with existing spectacle frames.  These magnifiers need a close working distance and vision can be blurred when looking up. This can be overcome with half- eye versions of the spectacles.  Electronic or video magnifiers are also available to provide real image magnification using a TV camera to create a magnified image on a monitor screen. They are usually used for near or intermediate tasks with the image presented on a screen near to the patient, although a camera pointing to a distant object can provide magnification again onto the screen. This CCTV system can particularly help when a longer duration task is to be carried out.  To view more details on the products available for near vision see the sections on Hand-held, Stand, Bar and Dome, Magnifying Spectacles, Spectacle-mounted and Electronic magnifiers in the Product Pages.