GSO 2" EAF Compatible Crayford Focuser for Reflectors - Dual Speed

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3. Description:
This very high quality, dual-speed Crayford focuser for reflector telescopes from Guan Sheng Optical (GSO) is a joy to use. You will wonder how you ever lived without it once you install it! It will make achieving precise focus for visual observations and astrophotography a breeze and you will experience very smooth and precisely controlled focuser motion with zero backlash and zero image shift.
CNC machined from aluminum and anodized black, this focuser comes with a base plate to attach to your reflector telescope. The inner drawtube glides on 4 precision bearings and a roller shaft and provides 40mm of focus travel. The inner barrel is baffled and painted a flat black to minimize reflections for maximum contrast.
The 2" focuser barrel features a brass compression ring so your eyepieces and other accessories will not be marred by the set-screw. Also included is a 1.25"-2" adapter with brass compression rings that is threaded to accept standard 2" filters.
The focuser also has two large thumbscrews. The thumbscrew on the telescope side can be used to lock the focuser, allowing the use of heavy accessories or cameras without fear or slippage or losing focus. The other thumbscrew on the eyepiece end can be used to adjust the tension of the focuser to achieve a focusing "feel" that you like. At the easiest (lightest) setting, the focuser moves extremely smoothly. At tighter settings, you can still use heavier accessories without sacrificing much of the smooth focuser action. GSO's rated load capacity for their Crayford focusers is a little less than 6 lbs (2.7 kgs).
Many other versions of GSO's reflector focusers have a rounded or curved housing over the focusing mechanism, making it either impossible or hard to attach ZWO's EAF for automatic focusing control. However, GSO redesigned the housing on this focuser with a flat surface and with additional screw holes to allow users to easily and directly mount the ZWO EAF using the standard mounting bracket that the EAF comes with. The housing in this version is also made of aluminum for a secure, robust fit. Imagers can now use the EAF to precisely control the focuser's movement for visual or critical imaging applications. Note that the EAF is not included and is sold separately.
4. Focuser Specifications (With Curved Base Plate):
• Minimum focuser height (with 1.25" adapter) = 3.27" (83mm). Note that in this position, the inner drawtube extends below the curved base plate by almost 1in (25mm) which may intrude into your scope's light path.
• Maximum focuser height (with 1.25" adapter) = 4.84" (123mm)
• Minimum focuser height (without 1.25" adapter) = 2.87" (73mm)
• Maximum focuser height (without 1.25" adapter) = 4.45" (113mm)
• Tube travel = 1.61" (41mm)
• Drawtube outer diameter (cut-out in your telescope tube must exceed this) = 2.29" (58.1mm)
• Focuser weight (with 1.25" adapter) = 1lb-12.6oz (810gm)
• Focus knob diameter = 1.57" (40mm)
• Microfocuser knob diameter = 1.06" (27mm)
• Microfocuser reduction ratio = 1:10
• Maximum outer body diameter = 3.23" (82mm)
• Drawtube threaded at eyepiece/camera end = No
• Can 2" eyepiece holder be unscrewed from drawtube? = No
• Millimeter markings on focuser drawtube: Yes
• Rotatable: No (But body can be rotated by loosening two allen screws that connect the focuser to the base plate)
• Dust plug: One 1.25" dust plug included
5. Additional Comments:
• Please note: Most GSO Crayford focusers have or will soon develop two bearing marks/lines on the upper side of the drawtube. This is caused by wear on the barrel anodizing where is makes contact with the roller bearings. In some focusers, you have to look hard to find these marks. In others, it is very prominent, even for brand new items received from GSO. This does not indicate a defective or used product and is essentially just cosmetic.
• No mounting screws are included with the base plate. You will need to provide your own.
• The focuser is shipped in a foam-fitted padded box.
• No instruction manual is included.
Other Information
- Country of Manufacture: Taiwan
3. Description:
This very high quality, dual-speed Crayford focuser for reflector telescopes from Guan Sheng Optical (GSO) is a joy to use. You will wonder how you ever lived without it once you install it! It will make achieving precise focus for visual observations and astrophotography a breeze and you will experience very smooth and precisely controlled focuser motion with zero backlash and zero image shift.
CNC machined from aluminum and anodized black, this focuser comes with a base plate to attach to your reflector telescope. The inner drawtube glides on 4 precision bearings and a roller shaft and provides 40mm of focus travel. The inner barrel is baffled and painted a flat black to minimize reflections for maximum contrast.
The 2" focuser barrel features a brass compression ring so your eyepieces and other accessories will not be marred by the set-screw. Also included is a 1.25"-2" adapter with brass compression rings that is threaded to accept standard 2" filters.
The focuser also has two large thumbscrews. The thumbscrew on the telescope side can be used to lock the focuser, allowing the use of heavy accessories or cameras without fear or slippage or losing focus. The other thumbscrew on the eyepiece end can be used to adjust the tension of the focuser to achieve a focusing "feel" that you like. At the easiest (lightest) setting, the focuser moves extremely smoothly. At tighter settings, you can still use heavier accessories without sacrificing much of the smooth focuser action. GSO's rated load capacity for their Crayford focusers is a little less than 6 lbs (2.7 kgs).
Many other versions of GSO's reflector focusers have a rounded or curved housing over the focusing mechanism, making it either impossible or hard to attach ZWO's EAF for automatic focusing control. However, GSO redesigned the housing on this focuser with a flat surface and with additional screw holes to allow users to easily and directly mount the ZWO EAF using the standard mounting bracket that the EAF comes with. The housing in this version is also made of aluminum for a secure, robust fit. Imagers can now use the EAF to precisely control the focuser's movement for visual or critical imaging applications. Note that the EAF is not included and is sold separately.
4. Focuser Specifications (With Curved Base Plate):
• Minimum focuser height (with 1.25" adapter) = 3.27" (83mm). Note that in this position, the inner drawtube extends below the curved base plate by almost 1in (25mm) which may intrude into your scope's light path.
• Maximum focuser height (with 1.25" adapter) = 4.84" (123mm)
• Minimum focuser height (without 1.25" adapter) = 2.87" (73mm)
• Maximum focuser height (without 1.25" adapter) = 4.45" (113mm)
• Tube travel = 1.61" (41mm)
• Drawtube outer diameter (cut-out in your telescope tube must exceed this) = 2.29" (58.1mm)
• Focuser weight (with 1.25" adapter) = 1lb-12.6oz (810gm)
• Focus knob diameter = 1.57" (40mm)
• Microfocuser knob diameter = 1.06" (27mm)
• Microfocuser reduction ratio = 1:10
• Maximum outer body diameter = 3.23" (82mm)
• Drawtube threaded at eyepiece/camera end = No
• Can 2" eyepiece holder be unscrewed from drawtube? = No
• Millimeter markings on focuser drawtube: Yes
• Rotatable: No (But body can be rotated by loosening two allen screws that connect the focuser to the base plate)
• Dust plug: One 1.25" dust plug included
5. Additional Comments:
• Please note: Most GSO Crayford focusers have or will soon develop two bearing marks/lines on the upper side of the drawtube. This is caused by wear on the barrel anodizing where is makes contact with the roller bearings. In some focusers, you have to look hard to find these marks. In others, it is very prominent, even for brand new items received from GSO. This does not indicate a defective or used product and is essentially just cosmetic.
• No mounting screws are included with the base plate. You will need to provide your own.
• The focuser is shipped in a foam-fitted padded box.
• No instruction manual is included.
3. Description:
This very high quality, dual-speed Crayford focuser for reflector telescopes from Guan Sheng Optical (GSO) is a joy to use. You will wonder how you ever lived without it once you install it! It will make achieving precise focus for visual observations and astrophotography a breeze and you will experience very smooth and precisely controlled focuser motion with zero backlash and zero image shift.
CNC machined from aluminum and anodized black, this focuser comes with a base plate to attach to your reflector telescope. The inner drawtube glides on 4 precision bearings and a roller shaft and provides 40mm of focus travel. The inner barrel is baffled and painted a flat black to minimize reflections for maximum contrast.
The 2" focuser barrel features a brass compression ring so your eyepieces and other accessories will not be marred by the set-screw. Also included is a 1.25"-2" adapter with brass compression rings that is threaded to accept standard 2" filters.
The focuser also has two large thumbscrews. The thumbscrew on the telescope side can be used to lock the focuser, allowing the use of heavy accessories or cameras without fear or slippage or losing focus. The other thumbscrew on the eyepiece end can be used to adjust the tension of the focuser to achieve a focusing "feel" that you like. At the easiest (lightest) setting, the focuser moves extremely smoothly. At tighter settings, you can still use heavier accessories without sacrificing much of the smooth focuser action. GSO's rated load capacity for their Crayford focusers is a little less than 6 lbs (2.7 kgs).
Many other versions of GSO's reflector focusers have a rounded or curved housing over the focusing mechanism, making it either impossible or hard to attach ZWO's EAF for automatic focusing control. However, GSO redesigned the housing on this focuser with a flat surface and with additional screw holes to allow users to easily and directly mount the ZWO EAF using the standard mounting bracket that the EAF comes with. The housing in this version is also made of aluminum for a secure, robust fit. Imagers can now use the EAF to precisely control the focuser's movement for visual or critical imaging applications. Note that the EAF is not included and is sold separately.
4. Focuser Specifications (With Curved Base Plate):
• Minimum focuser height (with 1.25" adapter) = 3.27" (83mm). Note that in this position, the inner drawtube extends below the curved base plate by almost 1in (25mm) which may intrude into your scope's light path.
• Maximum focuser height (with 1.25" adapter) = 4.84" (123mm)
• Minimum focuser height (without 1.25" adapter) = 2.87" (73mm)
• Maximum focuser height (without 1.25" adapter) = 4.45" (113mm)
• Tube travel = 1.61" (41mm)
• Drawtube outer diameter (cut-out in your telescope tube must exceed this) = 2.29" (58.1mm)
• Focuser weight (with 1.25" adapter) = 1lb-12.6oz (810gm)
• Focus knob diameter = 1.57" (40mm)
• Microfocuser knob diameter = 1.06" (27mm)
• Microfocuser reduction ratio = 1:10
• Maximum outer body diameter = 3.23" (82mm)
• Drawtube threaded at eyepiece/camera end = No
• Can 2" eyepiece holder be unscrewed from drawtube? = No
• Millimeter markings on focuser drawtube: Yes
• Rotatable: No (But body can be rotated by loosening two allen screws that connect the focuser to the base plate)
• Dust plug: One 1.25" dust plug included
5. Additional Comments:
• Please note: Most GSO Crayford focusers have or will soon develop two bearing marks/lines on the upper side of the drawtube. This is caused by wear on the barrel anodizing where is makes contact with the roller bearings. In some focusers, you have to look hard to find these marks. In others, it is very prominent, even for brand new items received from GSO. This does not indicate a defective or used product and is essentially just cosmetic.
• No mounting screws are included with the base plate. You will need to provide your own.
• The focuser is shipped in a foam-fitted padded box.
• No instruction manual is included.
Other Information
- Country of Manufacture: Taiwan
