TS-Optics 50 mm Guiding Scope and Finder Scope with 1.25" Receptacle

TS Mini Guide Scope for astrophotography

The guide scope is not heavier than a normal finder and fits into all standard finder shoes like they are used by Skywatcher, Vixen, GSO, TS-Optics, etc. With a suitable autoguider, you can guide telescopes up to 200 mm (8") aperture and a focal length of 1500 mm. The Guide Scope is the optimal solution for all amateuer astronomers who do not want to work with an off-axis guider or are not able to because of space issues, but their mount also have not the reserves for a large guiding scope.

Even less sensitive autoguiders can be used, as you can easily adjust the TSL501. Thus can always position a sufficiently bright guide star exactly in the center. Due to the large field of view, a suitable star will always be available in the field.

With an eyepiece, the TSL501 becomes a wide-field telescope, with a crosshair eyepiece, it becomes a finder. The former is especially convenient for owners of long focal length instruments, as they can often only now get a complete view of extended star clusters, nebulae or the Andromeda Galaxy.

Note: The focus position of the guiding scope allows the connection of cameras with a larger flange focal distance, but this usually means that you need the TSVF1 extension tube for eyepieces in order to be able to focus.

Mounting the guide scope

The guiding scope can be connected to the telescope in several ways, a basis for versatile use.

Connection to telescopes with standard finder shoe:

The Mini-Guidescope has a base for this finder base and connects directly like a finder.

Connection to telescopes with 1/4" photo thread:

Attach the supplied adapter plate to the thread, if necessary with a spacer for better alignment. Then attach the supplied finder base to the plate using the two small screws. Now the telescope has a standard finder base into which the foot of the guide tube mount fits.

Connection to dovetail bar:

The adapter plate can be attached to a dovetail barl using one of the supplied hexagon socket photo screws. You can then again attach the finder base, into which the base of the guide scope bracket will then fit. Now you can attach the dovetail bar to the telescope.

Connection to accessory clamp:

The adapter plate can be attached to an accessory clamp using one of the supplied hexagon socket tripod screws. You can then again attach the finder base, into which the base of the guide scope bracket will then fit. Now you can attach the accessory clamp to a second dovetail bar, such as is provided on some telescopes.

Connection to telescope tubes:

On larger diameter telescope tubes, with a little tinkering, you can attach the finder base, which then allows direct connection through the base of the guide scope mount.

The adaption of the autoguider to the 1.25" receptacle

The TSL501 offers a generously placed focus position behind the 1.25" receptacle, so you can focus all popular autoguiders, like M-Gen or the autoguiders from ZWO, like the ASI120 Mini, without problems.

Adaption of autoguiders with T2 connector:

An adapter from T2 to 1.25" is already supplied with most autoguiders. This is what you need for connecting. If you should not have an adapter, we recommend the (1.25" focal adapter). Just put the camera into the 1.25" opening and focus by shifting. The parfocal ring fixes the position with maximum sharpness. Thus you have to focus only once.

Adaption of autoguiders with C-mount connection:

For attaching these guiders, you need the adapter TS1-C. Apart from that, the procedure is the same as if adapting via T2 (see above).

Adaption of autoguiders with M28/1.25" filter thread:

Modern autoguiders like the ASI120Mini have a 1.25" housing with filter thread. In this case you need the adapter TSVF1. Apart from that, the procedure is the same as if adapting via T2 (see above).

Focusing the autoguider:

You need to focus only once, afterwards it is sufficient to put the autoguider into the guide scope and start. For calibrating autoguider and guide scope to each other, proceed as follows:

Thread the 1.25" barrel to the autoguider.

Push the 1.25" parfocal ring loosely over the barrel.

The put the autoguider into the guide scope and focus by shifting.

If required, you can adjust the sharpness even more accurate by rotating the objective and then locking it via the knurled ring.

If you have achieved optimal sharpness, shift the parfocal ring towards the receptacle until it stops, then lock it with the set screws.

Ready - now you have calibrated your autoguider to the guide scope. In future you only have to put the guider into the guide scope and then you can start right away.