Illuminated Reticle Eyepiece: Threaded on to t
he telescope s rear cell in front of the 62 T-A
dapter or Off-Axis Guider, above, and the camer
a body, the f/6.3 focal reducer/field flattener
? reduces the main telescope s focal ratio by
a factor of 0.63 (e.g. from f/10 to f/6.3), th
ereby reducing photographic exposure times by a
bout 50%. Designed primarily for f/10 and f/15
LX-series models, the focal reducer can also b
e used photographically and in CCD imaging appl
ications with f/6.3 SCT s, resulting in an effe
ctive focal ratio of f/4. The illuminated retic
le eyepiece ?, with its crossline reticle patt
ern red-illuminated for easy night visibility,
permits the observer to confirm the telescope s
tracking accuracy during an extended exposure.