A camera adapter is the coupling tube that connects your 35mm single lens reflex camera (with lens removed) to the focuser of your refractor or reflector for prime focus full disk lunar and deep space photography (and, in some cases, for planetary and lunar photography using eyepiece projection, as well). An optional T-ring connects your camera to the camera adapter. Most camcorders, digital cameras, and ultra-compact 35mm cameras with fixed or built-in zoom lenses do not have removable lenses and cannot be used for astrophotography.
You insert the chrome barrel of the camera adapter into the focuser tube of your telescope in place of the star diagonal and/or eyepiece. Your focuser must be equipped with a thumbscrew to hold the adapter in place. As the adapter and camera are held by only a single thumbscrew, be sure that the camera adapter is securely locked in place, particularly with refractors, to avoid the possibility of your camera accidentally slipping out of the focuser and falling to the ground. For this reason, these adapters are not recommended for use with catadioptric telescopes.
Focusing is done through your camera. As with tele-extenders, discussed elsewhere, the images in the normal viewfinder screen of most cameras will be dim (particularly when doing eyepiece projection photography). A clear glass focusing screen designed for long focal ratio telephoto lens use will be helpful if one is available for your particular camera. Check with your camera dealer to see if such a clear glass focusing screen is available. For specific instructions for using a camera adapter such as calculating powers and focal ratios in eyepiece projection photography using the "projection distance" figure given for each adapter, how to focus when the image is almost too dim to see, etc. see the "How To Use A Camera Adapter . . ." section of this web site.
Meade 1.25" Camera Adapter: two parts for both prime focus and eyepiece projection photography with 1.25" focuser refractors and reflectors; chrome barrel prime focus section unscrews from eyepiece holder tube and is used with an optional T-ring for prime focus lunar and terrestrial photography; prime focus section screws into eyepiece holder tube for eyepiece projection photography using the same optional T-ring; cannot be used with Meade 25mm or 40mm modified achromatic or 20mm and 26mm Super Plössl eyepieces, which are too long to fit in the eyepiece holder tube; eyepieces with rubber eyecups may not fit into the camera adapter without temporarily removing the eyecup; threaded for 1.25" filters; optional T-ring fits both sections; projection distance is 70mm. #1320
|Cross section of both portions of 1.25" camera adapter set up for eyepiece projection photography (Plössl eyepiece is shown within eyepiece holder tube)||Cross section of 1.25" camera adapter prime focus section set up for prime focus photography|
Meade 1.25" Variable Camera Adapter: three parts for both prime focus and eyepiece projection photography with 1.25" focuser refractors and reflectors; threaded for 1.25" filters; eyepiece projection section has two telescoping tubes that change projection distance from 95mm to 135mm; tubes are held firmly at desired projection distance by two thumbscrews; variable projection design allows changes in magnification to vary the image size over a small range without the need to change the eyepiece; eyepieces with rubber eyecups may not fit into the camera adapter without temporarily removing the eyecup; needs optional T-ring. #1321
Cross section of 1.25" variable camera adapter set up for eyepiece projection photography
(Plössl eyepiece is shown within telescoping tubes of eyepiece holder section)
Meade APO Focuser Sleeve Extension Tube: the tube length of Meade APO refractors is such that the focal plane is a considerable distance behind the end of the focuser drawtube to put it where an eyepiece is located when the standard equipment 2" star diagonal is used; if the 2" diagonal is removed to connect photographic accessories, the spacing provided by the star diagonal is lost, and the photographic accessories are positioned too close to the scope to reach focus; the focuser sleeve extension is a 2" long tube that extends the focuser drawtube length of Meade APO refractors to restore the light path length lost when the star diagonal is removed and allow camera adapters or a #UTA and SCT accessories to reach focus during photography; the APO focuser sleeve extension fits between the black focuser drawtube and the Universal Thread Adapter labeled #1 in the UTA diagram below. #13APO
Meade Universal Thread Adapter: labeled Part #1 in the illustration to the left, this threaded ring attaches to the 2.7" focuser drawtube of Meade APO refractors in place of the 2" diagonal holder; it allows the use of Meade and Celestron Schmidt-Cassegrain accessories the #62 T-adapter (labeled Part #2 in the illustration), the #8541 tele-extender, the #5151 or #5152 off-axis guider bodies, etc.; the APO refractors also require the #13APO focuser sleeve extension described above to reach focus (not shown in the illustration). #UTA
Questar 3.5" Camera Coupling Set: consists of a swivel coupling and three adapter tubes that stack together in various combinations for prime focus, eyepiece projection, and Barlow photography with 3.5" Questar telescopes and Questar P-mount T-rings, eyepieces, and Barlows only; coupling set is supplied with Questar spotting scopes, but is optional with astronomical and Duplex versions; swivel coupling attaches to Cassegrain focus at rear of Questar control box and allows the camera to be quickly ratoated from a vertical to a horizontal orientation and locked in place at any orientation; adapter tubes attach to swivel coupling and are stacked in various combinations (alone, or with Questar eyepieces, or optional 1.5x and 2x Questar Barlows) for focal lengths of 1400mm to 7400mm; the eyepiece projection distance varies depending on number and arrangement of adapter tubes and where eyepiece is positioned within coupling stack; needs optional Questar P-thread T-ring. #1393
Questar 7" Camera Coupling Set: similar to the 3.5" camera coupling set above, but designed for use with the 7" Questar only. #1397
TeleVue 1.25" Prime Focus Adapter: shown at the left in the photo; wide body adapter for unvignetted prime focus photography with TeleVue Ranger refractor, but can also be used with most reflectors or refractors equipped with a 1.25" focuser; threaded to accept 1.25" filters; needs optional T-ring. #1345
TeleVue 2" Prime Focus Adapter: shown at the right in the photo above; for unvignetted prime focus photography with TeleVues Pronto, TV-101, and Renaissance-101 refractors, but can also be used with most reflectors and refractors equipped with a 2" focuser; threaded to accept 48mm filters; extra-long to keep adapter perpendicular to the film plane for accurate focus over entire negative; needs optional T-ring. #1341
TeleVue Ranger/Pronto Photo Field Flattener: shown in the center in the photo above; auxiliary multicoated lens system has T-threads to mount between camera adapter and T-ring on TeleVue Ranger and Pronto refractors only; flattens normally slightly curved refractor field to provide tightly-focussed pinpoint star images across the entire field for deep space photography and sharper field-edge images in critical terrestrial photography; increases focal ratio slightly to f/7.4 (500mm focal length). #1347
TeleVue 0.8x Reducer/Photo Field Flattener: not shown; auxiliary multicoated lens system/prime focus adapter has 2" barrel to fit into 2" focuser of TeleVue TV-85 and Pronto refractors, as well as the 2" focuser drawtube of virtually any brand and model of quality doublet refractor (2" prime focus adapter #1341 is not needed); T-threads on rear of reducer allow 35mm camera body to be attached using a standard T-ring (not supplied); lens flattens normally slightly curved refractor field to provide tightly-focussed pinpoint star images across the entire field for deep space photography and sharper field-edge images in critical terrestrial photography; also acts as a 0.8x reducer lens to decrease TV-85 focal ratio slightly to f/5.6 (480mm focal length) and decrease Pronto focal ratio to f/5.4 (380mm focal length) for wider photographic fields. #1348
TeleVue Eyepiece Projection Adapter: two parts allow both prime focus photography with refractors or reflectors using 2" focusers, plus eyepiece projection with most 2" or 1.25" focuser refractors and reflectors using 1.25" eyepieces whose top (non-chrome) barrel is under 1.56" in diameter and 1.5" in length (such as the TeleVue 4.8mm Nagler and 8mm to 26mm Plössls); solid and stable design locks the eyepiece in place perpendicular to the film plane for accurate focus over entire negative; needs optional T-ring; projection distance is 154mm; needs 2" or 3.5" extension tube installed before the adapter to reach proper photographic focus with most scopes; TeleVue 85mm and 101mm scopes require both a 2" and a 3.5" extension tube before the adapter to reach proper photographic focus.