This GSO Dual-Speed Linear Focuser for Newtonian reflector telescopes features the most recent innovation in focuser design to hit the astronomy market in recent years. It is designed specifically to meet the heavier equipment and stability requirements of astrophotography equipment and heavy eyepieces. 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!
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. The new linear bearing focuser is 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. This linear bearing rail mechanism also allows the use of heavier loads (GSO's rated load capacity for their linear bearing focusers is about 9 lbs (4.1 kgs)).
Smooth Focusing Action
The ultra-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. You'll feel as if the focuser is gliding on air as you meticulously seek the perfect focus. 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 focusing tension can be controlled by another large screw on the underside of the focuser. The drawtube features a laser-etched measurement scale for quick and repeatable focusing.
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 linear 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 2".
Specifications (With Curved Base Plate)
• Minimum focuser height (without 1.25" adapter) = 3.05" (77.5mm)
• Maximum focuser height (without 1.25" adapter) = 5.05" (128mm)
• 2"-1.25" adapter height = 0.39" (10mm)
• Tube travel = 2" (50.8mm)
• Drawtube outside diameter (cut-out in your telescope tube must exceed this) = 2.32" (59mm)
• Steel rail width = 0.56" (14.1mm)
• Focuser weight (with 1.25" adapter) = 1lb-11.5oz (779gm)
• 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
• The focuser is shipped in a foam-fitted padded box.
• No instruction manual is included.
Jul 12, 2018
GSO Linear Dual Speed FocuserPros: Cons: Comments:
This Focuser is excellent.. And I have used or owned almost all of the Top of the Line Focusers..This Focuser holds all of my BIG 2" Eyepieces even with a 2" Barlow along with them. Very happy with the way this Focuser performs..Recommend !!!
This review was provided courtesy of AgenaAstro.comApr 2, 2018
too precisePros: Cons: Comments:
buy a dual speed economic focus that gives me a better performance than my Celestron C8n brings, and this does not disappoint me, I just had to get that if a longer screw because it is a little wider, but I'm super happy with the performance, now I can have more precision in the approach when doing astrophotography. additionally super pleased with the delivery was too efficient, I have 2 purchases made in Agenastro and I have not disappointed, greetings from Costa Rica.
This review was provided courtesy of AgenaAstro.comMar 25, 2018
Gaining Back Focus on a DobsonianPros: Cons: Comments:
Been engaged in astronomy for about four years. Have a 10" reflector and gradually got interested in astrophotography. As most of you know photography with a reflector is challenging. It is, however, an intriguing pursuit. This focuser is a necessary link and has improved my quest greatly.
This review was provided courtesy of AgenaAstro.comJan 21, 2018
Very nice focuserPros: Cons: Comments:
An amazing product for the price. High quality, heavy, velvet operation and well machined. The only minor complaint is that when the clutch screw is tightened to prevent the barrel slipping (in the case where its carrying more weight) the fine adjust no longer operates and just slips. But I still recommend it.
This review was provided courtesy of AgenaAstro.comMay 26, 2017
great little unitPros: Cons: Comments:
I bought this to replace stock rack and pinion focuser. I read some reviews and was a little worried I would need to take it apart to add grease but they were unfounded. It is quite smooth and I am very satisfied with my choice. I have an XT8 dob and I got the 1A mounting plate. I didn't like that the screws didn't go in perpendicular to the tube. I bought the 1B plate and installed that. Much better. I bought my scope in 2000 so I had to open up the focuser hole to fit. I had to drill some holes to fit. I found out about a "KNIBLER" tool on an astronomy sight and it worked good. It's like a mini punch and die . It's hand held , similar to a pair of plyers. Very little distortion. I found it on AMAZON for about 10. dollars.
This review was provided courtesy of AgenaAstro.com
JDSmart New Member
- Skill Level
- Time with Product
Jan 3, 2017
- User Notes:
- Review by Jeff S.
GSO 2" Linear Bearing Crayford Focuser for ReflectorsPros: Cons: Comments:
Upgraded my Celestron C8-N tube with this. Just replaced the stock 4mm screws on the original R&P Focuser with ones that are about a 1/4 inch longer and it was a direct fit using the Type 1A base plate. This thing is a huge improvement over the stock R&P Focuser.
This review was provided courtesy of AgenaAstro.comOct 2, 2016
Strong Construction,AccurateCons: Comments:
Very well made, very smooth. Only downside is limited range of focus. I have 2 Barlows and would have to change focus extension tube to use both where I didn't even need an extension tube before for either.
This review was provided courtesy of AgenaAstro.comJun 26, 2015
Very Happy with my purchase!Pros:
Easy to Use,Strong ConstructionCons:
I have an old Celestron G-8N Newtonian scope (Model 31058). It had stock old rack and pin style focuser. It was really rocky and very hard to culminate. After contacting Celestron and they recommended I look at the focusers that Agenaastro sells. I still wasn't sure this would fit my scope properly so I bought the base first and it fit perfect. Next I purchased this focuser. I am extremely happy with this purchase. I love how smooth the focuser moves and the fine tune nob really makes things a ton easier. Also I don't have to worry about the weight of my camera. I thing I'm most happy about is that I didn't have to modify my tube to get this to mount.
This review was provided courtesy of AgenaAstro.comMar 28, 2015
GSO 2" Linear Bearing Crayford FocuserPros:
I bought this focuser for my new dobsonian currently being made.
The focuser is very well and precisely made as advertised, and no flexure throughout the focus travel range thanks to its linear bearing feature.
Though the focuser motion is not silky smooth it is acceptable considering the price.
The only dissatisfaction is that this one is not a low profile focuser, which needs caution for designing the dobsonian so that there shall be no shade by the draw tube when installed.
This review was provided courtesy of AgenaAstro.comOct 18, 2014
Recommend to a friendPros:
Accurate,Strong ConstructionCons: Comments:
I use this in my 6" reflector, and I have bought other products from Agena Astro and like the service and the products. I also purchased Agena ED eyepieces and enjoy them. Looking forward to purchasing more.
This review was provided courtesy of AgenaAstro.comJun 17, 2014
Great 2" focuser at a super pricePros:
Lightweight,Strong Construction,CompactCons: Comments:
As with all purchases that I've made through Agena, I was more than pleased with this GSO 2" LB focuser. It will be used to replace an older Crayford style unit and will do so with ease. I've since machined parts for a remote control unit with parts from Hobby Engineering (miniature gearhead motor and bidirectional PWM kit) - great to be able to look at the monitor and focus an image remotely.
This review was provided courtesy of AgenaAstro.comJan 19, 2012
Best money ever spent!Pros:
Strong Construction,Accurate,Very smooth,Easy to UseCons:
I can't believe the difference this makes. I just replaced the plastic focuser on my Meade 10" starfinder EQ which I have been using for years. Best money I have ever spent. I love it.
This review was provided courtesy of AgenaAstro.comSort by
Manufacturer GSO Focuser Telescope Type Reflector