DIY Guide Scope Rings

Guide scope rings or guide rings are mechanisms used for mounting guide scopes. A guide scope is a telescope used to monitor tracking accuracy while a main telescope takes a long-exposure photo. Errors in tracking are detected with a guide scope by monitoring a guide star. Corrections are made by the mount to keep the guide star centered, and thus, keeping the main imaging telescope pointed at a target for the whole duration of an exposure.

DIY guide scope rings

This DIY guide scope rings set is used with a 60 mm f/5 guide scope and a 114 mm f/8 imaging telescope.

Related link: View all home-brewed DIY astronomy equipment

Night Sky in Focus | Astronomy and Amateur Radio
© Anthony Urbano | Manila, Philippines

DIY Smartphone-to-Telescope Adapter

Smartphones can be used to image the moon by holding it next to the eyepiece of a telescope. For smart phone cameras, a mid-power eyepiece such as a 25 mm eyepiece yields good results. This imaging method is called afocal imaging, in which a camera with its lens is mounted next to another image-forming optical system such as a telescope or a pair of binoculars. To hold the phone camera steady while taking a photo, a smart phone-to-telescope adapter may be used. The adapter below was built using a mobile phone holder attached onto the side of a 90 degree diagonal mirror (star diagonal).

Mobile phone holder attached to a star diagonal
Mobile phone holder used as a smart phone-to-telescope adapter


Another version of a smartphone-to-telescope may be built using inexpensive materials using a piece of plywood, hose clamp, screw, and rubber bands. Secure the hose clamp onto the plywood using screws. Use the hose clamp to hold the eyepiece in place. Use rubber bands to hold the smart phone camera and adjust as necessary.

Inexpensive home-brewed adapter made from plywood, hose clamp, and other materials
Low-cost smart phone-to-telescope adapter


Related link: Universal Camera Adapter

Night Sky in Focus | Astronomy and Amateur Radio
© Anthony Urbano | Manila, Philippines

DIY Dew Heater

Dew heaters or heater pads are telescopes accessories used to prevent dew from forming on the telescope’s lens. During long imaging sessions, it is not uncommon for the main lens of refractors and SCTs to form dew. A heater is used to keep the objective lens at a temperature a few degrees C above the dew point to prevent the formation of dew.

Dew heater made from inexpensive nichrome wires

I used nichrome wires from a local electronics store to build several DIY heater pads for my telescope, which I find useful in keeping the lenses free from dew especially when imaging in remote observing sites.

To view posts on DIY projects and astronomical equipment, click here.

Night Sky in Focus | Astronomy and Amateur Radio
© Anthony Urbano | Manila, Philippines

DIY Plate for Telescopes

I’ve built an aluminum plate for my equatorial mount to allow it to carry the main telescope and the guide scope for autoguiding purposes. In autoguiding, it is important to minimize flexing between the imaging telescope and the guide scope, thus, a plate with suitable thickness helps address this problem. This DIY plate measures 12 cm by 20 cm by 1 cm and made from a solid aluminum plate from a local metals supply shop. Holes have been drilled on the plate to allow attachment of various loads such as DSLR cameras and different telescopes.

Kenko NES mount with a DIY aluminum plate

To view posts on DIY projects and astronomical equipment, click here.

Related link: Sky-Watcher 100ED Refractor

Night Sky in Focus | Astronomy and Amateur Radio
© Anthony Urbano | Manila, Philippines

Peltier-Cooled DSLR Project

During an exposure, the imaging sensor of a DSLR warms up, resulting to noisy images. By cooling down the sensor, it is possible to eliminate or somehow minimize this thermal noise.

Cooling the camera’s sensor using a Peltier module

I have made a number of attempts to accomplish this with a Canon 450D and a Peltier module, however, it appears it is very difficult to implement without running into problems such as condensation and frosting.

M42 imaged with a Peltier-cooled filter-modified Canon 450D. No dark frames were used in this image. Image processed in SIRIL. The DSLR’s stock filter was replaced with a Baader UV-IR blocking filter.

Related link: View all home-brewed DIY astronomy equipment

Night Sky in Focus | Astronomy and Amateur Radio
© Anthony Urbano | Manila, Philippines

DIY Logitech 4000 Guide Camera

The Logitech 4000 webcam is capable of imaging planets and can be modified to take long exposure images to serve as a guide camera. The modification requires a serial port to externally control the camera’s exposure time using a guiding software such as GuideMaster and PHD Guiding.

Modified Logitech 4000 Guide Camera

The long- exposure modification allows the camera to detect faint guide stars, which is a useful feature for a guide camera. The diagram shown here was a modified version of M. Burri’s (2002) parallel port interface for a Logitech 3000 which I have adapted to work with the newer Logitech 4000 and a serial port.

Related link: View all home-brewed DIY astronomy equipment

Night Sky in Focus | Astronomy and Amateur Radio
© Anthony Urbano | Manila, Philippines