William Optics 50mm f/4 Guide Scope with 1.25" RotoLock III - Available in 4 Colors

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Please note: This item is now only available in black and gray trims. All other trim colors have been discontinued by William Optics
All new, unique, fully multi coated WO 50mm f/4 guiding scope with 1.25" RotoLock adapter that fits perfectly on your William Optics telescope.
Features:
- High-quality 50mm f/4 achromatic objective
- 1.25" RotoLock camera holder
- Rotolock adapter rides on an M48 threaded barrel, allowing it to be screwed in or out to obtain 8mm of focus travel. Lock ring included.
- White powder painted with an option of several trims (select option above)
- Perfectly suited for William Optics or other refractors
Specifications:
- Tube outside diameter = 54.5mm (2.15")
- Dewshield outside diameter = 58.2mm (2.29")
- Maximum length = 265mm (10.4")
- Rotolock focus travel = 8mm (0.31")
- Weight = 520g (18.3oz)
- Finder bracket sold separately
Back focus Information:
Out of the box, this guidescope comes with a 1.25" Rotolock adapter/eyepiece holder. Also included separately is an M48-threaded extension tube. This extension tube can be used by itself with the optical tube instead of the Rotolock adapter, or it can be used in conjunction with the Rotolock adapter.
The required back focus of this guide scope will vary depend on the configuration you use these two items in. See photo # 3 above illustrating this. Note that the back focus numbers in the diagram below are with the M48 adapter or the Rotolock adapter fully screwed on to the finder tube. Since theses adapters can be extended by an additional 8mm as explained above, you can effectively reduce the back focus numbers in the figure by up to 8mm from those specified below by partly unscrewing whichever adapter(s) you are using.
Configuration A above can be used if your guide camera has a short nosepiece with an M48 female thread.
Configuration B above is for use with cameras that have a 1.25" nosepiece. You can slide the camera in or out manually from the Rotolock adapter for coarse focus and to place the sensor at approximately the correct location near the focal plane.
Configuration C is for use with 1.25" "Mini" or "cylinder" type cameras that are very widely used with such guidescopes. Again, you can manually slide the camera in or out to get it near focus. Depending on your camera's back focus, you may need to use a 1.25" extension tube (often included with the camera itself) to reach focus.
If your application requires an M42x0.75 T/T2 thread, you can purchase an M48-to-T thread adapter such as the Blue Fireball T-06 adapter to convert the M48 male thread on the rear of the guidescope or the included M48 adapter into a T/T2 male thread. For example, this would be useful if you wish to connect your camera featuring a female T thread directly to the guidescope for a more secure threaded connection. In another example, some people prefer to replace the included 1.25" Rotolock holder with a different 1.25" visual back (such as the ZWO 1.25" Helical Focuser # HF1.25) that allows easier fine focus control. Make sure to work out your back focus requirements carefully as you may need spacers to place the guidecam sensor at the focal plane.
Additional product information:





Other Information
- Country of Manufacture: Taiwan
All new, unique, fully multi coated WO 50mm f/4 guiding scope with 1.25" RotoLock adapter that fits perfectly on your William Optics telescope.
Features:
- High-quality 50mm f/4 achromatic objective
- 1.25" RotoLock camera holder
- Rotolock adapter rides on an M48 threaded barrel, allowing it to be screwed in or out to obtain 8mm of focus travel. Lock ring included.
- White powder painted with an option of several trims (select option above)
- Perfectly suited for William Optics or other refractors
Specifications:
- Tube outside diameter = 54.5mm (2.15")
- Dewshield outside diameter = 58.2mm (2.29")
- Maximum length = 265mm (10.4")
- Rotolock focus travel = 8mm (0.31")
- Weight = 520g (18.3oz)
- Finder bracket sold separately
Back focus Information:
Out of the box, this guidescope comes with a 1.25" Rotolock adapter/eyepiece holder. Also included separately is an M48-threaded extension tube. This extension tube can be used by itself with the optical tube instead of the Rotolock adapter, or it can be used in conjunction with the Rotolock adapter.
The required back focus of this guide scope will vary depend on the configuration you use these two items in. See photo # 3 above illustrating this. Note that the back focus numbers in the diagram below are with the M48 adapter or the Rotolock adapter fully screwed on to the finder tube. Since theses adapters can be extended by an additional 8mm as explained above, you can effectively reduce the back focus numbers in the figure by up to 8mm from those specified below by partly unscrewing whichever adapter(s) you are using.
Configuration A above can be used if your guide camera has a short nosepiece with an M48 female thread.
Configuration B above is for use with cameras that have a 1.25" nosepiece. You can slide the camera in or out manually from the Rotolock adapter for coarse focus and to place the sensor at approximately the correct location near the focal plane.
Configuration C is for use with 1.25" "Mini" or "cylinder" type cameras that are very widely used with such guidescopes. Again, you can manually slide the camera in or out to get it near focus. Depending on your camera's back focus, you may need to use a 1.25" extension tube (often included with the camera itself) to reach focus.
If your application requires an M42x0.75 T/T2 thread, you can purchase an M48-to-T thread adapter such as the Blue Fireball T-06 adapter to convert the M48 male thread on the rear of the guidescope or the included M48 adapter into a T/T2 male thread. For example, this would be useful if you wish to connect your camera featuring a female T thread directly to the guidescope for a more secure threaded connection. In another example, some people prefer to replace the included 1.25" Rotolock holder with a different 1.25" visual back (such as the ZWO 1.25" Helical Focuser # HF1.25) that allows easier fine focus control. Make sure to work out your back focus requirements carefully as you may need spacers to place the guidecam sensor at the focal plane.
Additional product information:





Please note: This item is now only available in black and gray trims. All other trim colors have been discontinued by William Optics
All new, unique, fully multi coated WO 50mm f/4 guiding scope with 1.25" RotoLock adapter that fits perfectly on your William Optics telescope.
Features:
- High-quality 50mm f/4 achromatic objective
- 1.25" RotoLock camera holder
- Rotolock adapter rides on an M48 threaded barrel, allowing it to be screwed in or out to obtain 8mm of focus travel. Lock ring included.
- White powder painted with an option of several trims (select option above)
- Perfectly suited for William Optics or other refractors
Specifications:
- Tube outside diameter = 54.5mm (2.15")
- Dewshield outside diameter = 58.2mm (2.29")
- Maximum length = 265mm (10.4")
- Rotolock focus travel = 8mm (0.31")
- Weight = 520g (18.3oz)
- Finder bracket sold separately
Back focus Information:
Out of the box, this guidescope comes with a 1.25" Rotolock adapter/eyepiece holder. Also included separately is an M48-threaded extension tube. This extension tube can be used by itself with the optical tube instead of the Rotolock adapter, or it can be used in conjunction with the Rotolock adapter.
The required back focus of this guide scope will vary depend on the configuration you use these two items in. See photo # 3 above illustrating this. Note that the back focus numbers in the diagram below are with the M48 adapter or the Rotolock adapter fully screwed on to the finder tube. Since theses adapters can be extended by an additional 8mm as explained above, you can effectively reduce the back focus numbers in the figure by up to 8mm from those specified below by partly unscrewing whichever adapter(s) you are using.
Configuration A above can be used if your guide camera has a short nosepiece with an M48 female thread.
Configuration B above is for use with cameras that have a 1.25" nosepiece. You can slide the camera in or out manually from the Rotolock adapter for coarse focus and to place the sensor at approximately the correct location near the focal plane.
Configuration C is for use with 1.25" "Mini" or "cylinder" type cameras that are very widely used with such guidescopes. Again, you can manually slide the camera in or out to get it near focus. Depending on your camera's back focus, you may need to use a 1.25" extension tube (often included with the camera itself) to reach focus.
If your application requires an M42x0.75 T/T2 thread, you can purchase an M48-to-T thread adapter such as the Blue Fireball T-06 adapter to convert the M48 male thread on the rear of the guidescope or the included M48 adapter into a T/T2 male thread. For example, this would be useful if you wish to connect your camera featuring a female T thread directly to the guidescope for a more secure threaded connection. In another example, some people prefer to replace the included 1.25" Rotolock holder with a different 1.25" visual back (such as the ZWO 1.25" Helical Focuser # HF1.25) that allows easier fine focus control. Make sure to work out your back focus requirements carefully as you may need spacers to place the guidecam sensor at the focal plane.
Additional product information:





Other Information
- Country of Manufacture: Taiwan
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William Optics 50mm f/4 Guide Scope with 1.25" RotoLock III - Available in 4 Colors


















