How to Choose Fieldscopes How to choose eyepieces

Magnification of Fieldscopes

The magnification of a Fieldscope is determined by the combination of the body's effective diameter of the objective lens and the eyepiece. Eyepieces are available in various types including a wide type or a zoom type, and eyepieces for digiscoping have also been developed. Choose the appropriate magnification according to your needs.

Combination examples of eyepiece and magnification

Eyepiece	Wide type: fixed magnification (low magnification)		Wide type: fixed magnification (high magnification)		Zoom type
	Recommended for observing near and wide-moving subjects.		Recommended for observing distant subjects, details and for fixed-point observation.		Non-step adjustable magnification from low to high.
Effective diameter of the objective lens	85mm	65mm	85mm	65mm	85mm	65mm
Magnification	20x	16x	75x	60x	20-60x	16-48x
Field of view*	20x		75x		20-60x

• *When using 85mm effective diameter of the objective lens
• *Photos are simulated viewfinder images.

Comparing zoom type eyepiece and fixed magnification eyepiece

A Nikon's zoom type eyepiece allows you to adjust the magnification at any position from low to high and lets you enjoy various magnifications. Compared with a fixed-magnification eyepiece, the field of view of a zoom type eyepiece is narrower, however, if you plan to use a Fieldscope in a variety of situations, it is recommended for your first eyepiece. A fixed-magnification eyepiece is designed to secure a wider field of view. You can choose the most appropriate magnification eyepiece according to your particular needs, and you will obtain high-quality images whichever strength you select, because the optical structure is optimized for each magnification.
If your observation conditions are fixed and require a wider field of view, or for digiscoping where vignetting must be minimized, fixed-magnification eyepieces are recommended.