Double Star Charts: Using the Select Double Stars Telrad Guide

What these charts assume you already have

The Select Double Stars charts are designed to work in conjunction with a Telrad red-bullseye finder. That is the key compatibility fact: the charts show star patterns and a bullseye overlay so you can position your Telrad to match the chart, then look through the finder and see the same pattern. Without a Telrad-style bullseye finder, the overlay will not line up with what you see.

The set covers 49 double and multiple stars, with 49 sturdy, laminated charts. Targets range from well-known pairs such as Albireo (Beta Cygni), Mizar (Zeta Ursae Majoris), and Castor (Alpha Geminorum) to tighter challenges like Epsilon Lyrae (the Double Double) and Otto Struve 215. Each chart is a separate page, so you can pull out just the targets you plan to observe.

Chart construction that affects how you use them

• Select Double Stars - Telrad Finder Charts: Black printing and stars on a white background make the charts easily readable with a red flashlight. Red light preserves dark adaptation, and the high-contrast white background keeps the chart legible without switching to white light.

  

• Select Double Stars - Telrad Finder Charts: Printed on white vellum card stock and fully laminated on both sides for dew and water resistance. Lamination means you can handle the charts with damp hands or set them on a dewy table without the paper turning to pulp.
• Select Double Stars - Telrad Finder Charts: Bound with plastic comb binders that allow the charts to lay flat and stay flat in breezy conditions. A flat chart is easier to match to the sky one-handed, and the comb binding keeps pages from flipping in wind.

Star hopping with a Telrad and these charts

The process below follows the chart design: match the star pattern, position the bullseye, then confirm in the eyepiece. It assumes your Telrad is already mounted and aligned with your telescope, since the charts do not include alignment instructions.

1. Pick a target and pull its chart: Choose one double star from the 49 listed, such as Gamma Andromeda (Almach) or Beta Cygni (Albireo), and open that chart. The comb binding lets it lie flat on a table or clip board.
2. Read the star pattern around the target: Each chart shows the star field with black stars on white. Identify the brightest nearby stars and the shape they form, because that pattern is what you will see through the Telrad.
3. Position your Telrad bullseye to match: Look through the Telrad and move the telescope until the bright stars in the finder match the pattern on the chart. The chart's bullseye overlay corresponds to the Telrad's illuminated rings, so align the rings with the chart's rings rather than guessing.
4. Confirm the double in the eyepiece: Once the bullseye is positioned, switch to the eyepiece. The chart tells you which star is the double; the eyepiece shows whether you have split it. If the field does not match, return to the Telrad and recheck the pattern before moving on.

Beginner-friendly targets in the set

The chart list includes pairs that are well known and easier to locate, plus tighter pairs that reward patience. The catalog does not give separation figures, so treat this as a starting order rather than a difficulty ranking.

• Beta Cygni (Albireo): A classic double in Cygnus, useful for learning the chart-to-Telrad matching process because the surrounding star pattern is distinctive.
• Zeta Ursae Majoris (Mizar): In the Big Dipper, easy to find and a good first star hop with the Telrad.
• Alpha Geminorum (Castor): In Gemini, a well-known multiple star that gives you practice reading a busier chart.
• Epsilon Lyrae (the Double Double): A tighter target near Vega; the chart helps you land on the right star, though splitting it depends on your optics and seeing.

Dew, breeze, and red light in practice

The lamination is the feature you will notice most on a long night. Dew forms on charts left on an observing table, and laminated pages wipe dry without ink running. The comb binding lets the book lie flat, which matters when you are holding a red flashlight in one hand and adjusting the Telrad with the other.

Use a red flashlight rather than a white one; the black-on-white printing is specifically arranged to be readable under red light. If the wind picks up, the comb binding keeps the pages from turning, but the charts are still lightweight card stock, so clip the book to a table or observing tray if you step away.

What the set does not tell you

• Select Double Stars - Telrad Finder Charts: The supplied record lists 49 double and multiple stars and 49 charts but does not include separation, magnitude, or position angle data. You can use the charts to find targets, but you will need another reference if you want to know how tight each pair is before you observe.
• Select Double Stars - Telrad Finder Charts: The charts are described as designed to work with a Telrad red-bullseye finder; no other finder compatibility is confirmed in the supplied information. If you use a different finder, the bullseye overlay may not correspond to your reticle, so plan on a different chart style.