In every telescope, the focuser is attached close to the focal point of the light-gathering optic. Eyepieces can be connected to the focuser. For astrophotography, a camera is attached to the focuser, and the focuser serves to focus the camera.
Omegon
2'' helical focuser
$ 99.00
ASToptics
1.25" helical focuser (M42/T2)
$ 106.00
Omegon
2'' SC Hybrid Crayford focuser, dual speed
$ 359.00
ASToptics
1.25" helical focuser (M36)
$ 106.00
Omegon
2" Newton Hybrid Crayford focuser, dual speed
$ 289.00
Omegon
Steeltrail 2'' Newtonian dual speed Crayford focuser
$ 289.00
Omegon
2'' Newtonian Crayford focuser, dual speed 1:10
$ 169.00
KineOptics
Focuser HC-2 Helical Crayford 2"
$ 297.00
Starlight Instruments
FTF2020BCR 2" Feather Touch Crayford focuser with 2.0" focus travel and brake
Our price:
RRP:
$ 1,480.00
$ 950.00
Auriga
Focuser Newton DSF 2"
$ 197.00
Omegon
Focuser Feathertouch FTF33235B-A BigRC
Our price:
RRP:
$ 999.00
$ 799.00
Skywatcher
1.25/2" Rack & Pinion Focuser
$ 65.00
TS Optics
short T2 Helical Focuser & Adapter
Our price:
RRP:
$ 106.00
$ 74.00
Baader
Focuser Diamond Steeltrack BDS-NT 2"
$ 368.00
TS Optics
Focuser Crayford 2''
$ 127.00
Starlight Instruments
Feather Touch 3" focuser body with brake
Our price:
RRP:
$ 1,480.00
$ 1,030.00
TS Optics
Focuser Crayford 2"
$ 233.00
TS Optics
Focuser R&P 3"
$ 468.00
TS Optics
Focuser R&P 2.5"
$ 320.00
Baader
Focuser Diamond Steeltrack BDS-RT 2"
$ 382.00
Baader
Focuser Diamond Steeltrack BDS-SC 2"
$ 389.00
TS Optics
Focuser Crayford 2"
$ 212.00
Skywatcher
2" Crayford Focuser for Explorer Newtonian Reflectors
$ 208.00
Artesky
Focuser RC 3"
$ 452.00
Lunt Solar Systems
Focuser Umbausatz für LS80MT
$ 453.00
Lunt Solar Systems
Focuser conversion kit for LS130MT
$ 640.00
PegasusAstro
Fokussiermotor FocusCube v3 Universal
$ 308.00
TS Optics
Focuser R&P 2"
$ 276.00
PegasusAstro
Rotator Falcon V2
$ 780.00
TS Optics
Focuser UNC Gen 2 Newton 2"
$ 276.00
PlaneWave
Focuser Hedrick 3.5" CDK 14/17/20/24
$ 1,650.00
Wega Telescopes
EAF Motoranbaukit für William Optics SpaceCat und RedCat
$ 159.00
Wega Telescopes
EAF Motoranbaukit für TS Optics 2" OAZ
$ 106.00
Omegon
Bundle comprising 80mm to 78mm adapter + adapter plate
Our price:
RRP:
$ 138.90
$ 89.00
Omegon
Bundle comprising adapter 80mm + adapter plate
Our price:
RRP:
$ 133.90
$ 89.00
iOptron
Electronic Automatic Focuser iEAF
$ 276.00
Eyepieces and cameras are usually equipped with connector sockets. Two diameters have been established for the connector socket, which are specified in inches: 1.25" = 31.8mm and 2" = 50.8mm.
The focuser consists of two interlocking and sliding tubes, so that the eyepiece can be moved into focus using a small wheel. Not only eyepieces can be attached to focusers, but cameras as well.
Precise focusing is especially important for astrophotography. Therefore, high-quality focusers with reduction adjustment should be used for this application. For astrophotography, many focusers also have a connector thread, so that the camera is screwed into place instead of being be plugged in.
Simple focusers are adjusted using a rack and pinion mechanism. In the higher quality versions, this rack and pinion is angled and made of brass. Instead of a rack and pinion, the adjustment can also be made by exerting pressure on a special surface. Such focusers are usually referred to as Crayford focusers.
Helical focusers work in a completely different way. Here, the adjustment is made by rotating the inner barrel using a longitudinal screw (helix). One advantage is that a rotary knob is not necessary, which can get in the way, for example, of a guidescope.
As a rule, focusers can also be motorised. This improves focusing accuracy and also allows the remote operation of the telescope.