GSO 2" Rack & Pinion Focuser for Reflectors - Dual Speed
Sku:
PAF-GS-N2-M-R&P-DW444
Mfg #:
DW444
Item Can Ship:
Worldwide
The price depends on the chosen options
Final product price
In Stock
(10+ Available)
Stock listed above is accurate & shown in real time
Ships by Next Business Day
Free Shipping
Contiguous US Customers:
All items we sell ship for free within the Contiguous US. Shipping will be via the cheapest shipping method which will vary depending on the items in your order. During checkout, you may also be shown other optional faster shipping choices.
US Customers in Hawaii and Alaska:
Free shipping applies to almost all products. A few large telescopes and mounts are excluded from this free shipping offer. For these items, please contact us to obtain a shipping quote before you check out using the online shopping cart.
International Customers:
Free shipping does not apply to international orders. During check-out, you will be presented with several shipping choices and costs. However, the export of some items may be restricted outside the US due to size or manufacturer restrictions.
SKU:
PAF-GS-N2-M-R&P-DW444
Mfg #:
DW444
Item Can Ship:
Worldwide
Description
Description
3. Description:
This Rack-and-Pinion (R&P) Focuser for Newtonian reflector telescopes is GSO's latest offering for the heavy imaging loads that today's focusers are often called upon to carry. The linear stability and repeatable quality of focus reached with this focuser will have you returning night after night for more spectacular views, sharper images, and consistent enjoyment!
A. Eliminate Focuser Drawtube Slop
In conventional Crayford focusers, the drawtube is held in place by four roller bearings. Because of the small area of contact between the focuser tube and these bearings, changes in load or telescope orientation can cause some amount of slop in the focuser drawtube. Newer linear bearing focuser are built with a cutting-edge rail system made of stainless steel which provides extended, consistent, and linear contact with the focusing mechanism and the inside of the focuser body, even when the focuser is fully extended. The result is zero flexure throughout the focus travel range, even in the worst case scenario when the focuser is parallel to the ground and carrying a heavy load such as a large CCD camera. However, the load capacity of linear bearing focusers, while more than that or Crayfords, may still not suffice. GSO's R&P focusers offer the best of both worlds: a rack-and-pinion focus mechanism on the underside of the drawtube to lift even heavier loads as well as a steel rail on the upper side for rock solid stability. GSO's rated load capacity for their R&P focusers is over 22 lbs (10 kgs).
B. Smooth Focusing Action
The smooth focuser adjustment knob is only topped by the 10:1 fine adjustment knob which yields superior fine-tuning that will stay in place without slippage for hours on end. For critical imaging applications, the focuser position can be locked in place via the large thumbscrew provided for this purpose on the top of the focuser. The drawtube features a laser-etched measurement scale for quick and repeatable focusing.
C. Very High Quality Construction and Features
The highly polished, anodized black aluminum is complemented by the meticulous CNC machining. Every part is carefully selected and designed to deliver a focusing system that will provide both beauty and quality for years to come. The 2" focuser barrel features a brass compression ring. Also included is a 2"-1.25" adapter with brass compression rings and threads to accept standard 2" filters. The focus travel is a generous 50mm (almost 2").
D. Out of the Box Compatibility with the ZWO EAF Electronic Automatic Focuser
Some 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. After our prodding for almost 2 years, GSO redesigned the housing 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.
E. Terminating M56 Thread
The focuser drawtube of this item features a removeable M56x0.75 threaded 2" ring with a male thread on one side and a female thread on the other. This M56 terminating male thread on the drawtube 2" ring or allows you to directly mate other optional M56x0.75 threaded adapters and accessories (such as a Baader clicklock visual back or a GSO M56 camera rotator) for a more secure connection.
4. Specifications (With Curved Base Plate)
• Minimum focuser height (without 1.25" adapter) = 3.11" (79.0mm). Note that in this position, the inner drawtube extends below the curved base plate by about 32mm which may intrude into your scope's light path.
• Maximum focuser height (without 1.25" adapter) = 5.08" (129.0mm)
• 2"-1.25" adapter height = 0.39" (10mm)
• Tube travel = 1.97" (50mm)
• Drawtube outside diameter (cut-out in your telescope tube must exceed this) = 2.32" (59mm)
• Steel rail/rack widths = 0.56" (14.1mm)
• Focuser weight (with 1.25" adapter) = 1lb-14.3oz (860gm)
• Focus knob diameter = 1.57" (40mm)
• Microfocus knob diameter = 1.06" (27mm)
• Maximum outer body diameter = 3.23" (82mm)
• Measurement scale 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:
• 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.
Specifications
Specifications
| Product Banner Type | new |
|---|---|
| Free Shipping Graphic | Free US Shipping |
| Hide Found a better Shipped Price on Frontend? | No |
Reviews / Q&A
Reviews / Q&A
Related Products
View All
Description
Reviews / Q&A
Description
3. Description:
This Rack-and-Pinion (R&P) Focuser for Newtonian reflector telescopes is GSO's latest offering for the heavy imaging loads that today's focusers are often called upon to carry. The linear stability and repeatable quality of focus reached with this focuser will have you returning night after night for more spectacular views, sharper images, and consistent enjoyment!
A. Eliminate Focuser Drawtube Slop
In conventional Crayford focusers, the drawtube is held in place by four roller bearings. Because of the small area of contact between the focuser tube and these bearings, changes in load or telescope orientation can cause some amount of slop in the focuser drawtube. Newer linear bearing focuser are built with a cutting-edge rail system made of stainless steel which provides extended, consistent, and linear contact with the focusing mechanism and the inside of the focuser body, even when the focuser is fully extended. The result is zero flexure throughout the focus travel range, even in the worst case scenario when the focuser is parallel to the ground and carrying a heavy load such as a large CCD camera. However, the load capacity of linear bearing focusers, while more than that or Crayfords, may still not suffice. GSO's R&P focusers offer the best of both worlds: a rack-and-pinion focus mechanism on the underside of the drawtube to lift even heavier loads as well as a steel rail on the upper side for rock solid stability. GSO's rated load capacity for their R&P focusers is over 22 lbs (10 kgs).
B. Smooth Focusing Action
The smooth focuser adjustment knob is only topped by the 10:1 fine adjustment knob which yields superior fine-tuning that will stay in place without slippage for hours on end. For critical imaging applications, the focuser position can be locked in place via the large thumbscrew provided for this purpose on the top of the focuser. The drawtube features a laser-etched measurement scale for quick and repeatable focusing.
C. Very High Quality Construction and Features
The highly polished, anodized black aluminum is complemented by the meticulous CNC machining. Every part is carefully selected and designed to deliver a focusing system that will provide both beauty and quality for years to come. The 2" focuser barrel features a brass compression ring. Also included is a 2"-1.25" adapter with brass compression rings and threads to accept standard 2" filters. The focus travel is a generous 50mm (almost 2").
D. Out of the Box Compatibility with the ZWO EAF Electronic Automatic Focuser
Some 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. After our prodding for almost 2 years, GSO redesigned the housing 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.
E. Terminating M56 Thread
The focuser drawtube of this item features a removeable M56x0.75 threaded 2" ring with a male thread on one side and a female thread on the other. This M56 terminating male thread on the drawtube 2" ring or allows you to directly mate other optional M56x0.75 threaded adapters and accessories (such as a Baader clicklock visual back or a GSO M56 camera rotator) for a more secure connection.
4. Specifications (With Curved Base Plate)
• Minimum focuser height (without 1.25" adapter) = 3.11" (79.0mm). Note that in this position, the inner drawtube extends below the curved base plate by about 32mm which may intrude into your scope's light path.
• Maximum focuser height (without 1.25" adapter) = 5.08" (129.0mm)
• 2"-1.25" adapter height = 0.39" (10mm)
• Tube travel = 1.97" (50mm)
• Drawtube outside diameter (cut-out in your telescope tube must exceed this) = 2.32" (59mm)
• Steel rail/rack widths = 0.56" (14.1mm)
• Focuser weight (with 1.25" adapter) = 1lb-14.3oz (860gm)
• Focus knob diameter = 1.57" (40mm)
• Microfocus knob diameter = 1.06" (27mm)
• Maximum outer body diameter = 3.23" (82mm)
• Measurement scale 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:
• 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.
Specifications
| Product Banner Type | new |
|---|---|
| Free Shipping Graphic | Free US Shipping |
| Hide Found a better Shipped Price on Frontend? | No |
Reviews / Q&A
Related Products
View All
GSO 2" Rack & Pinion Focuser for Reflectors - Dual Speed