IC4756 "Graff's Cluster" and NGC6633 "Captian Hook Cluster"

Lens aperture: f/4 Darks: 60s x 40 @ ISO 800 Offsets/Bias: 1/4000s x 20 @ ISO 800 Guide scope lens aperture: f/3.5 IC4756 "Graff's Cluster" NGC6633 "Captain Hook Cluster" ------------------------------------------------------ Two bright and beautiful open star clusters. IC4756 belongs to the Serpens constellation, while NGC6633 belongs to Ophiuchus. These two clusters are located close to each other in the sky and also have other names. IC4756, named after the Polish-German astronomer Kasimir Romuald Graff, is also called the "Secret Garden Cluster." NGC6633 is also known as the "Wasp-Waist Cluster." Additionally, these two clusters, NGC6633 and IC4756, are together referred to as "Tweedledum and Tweedledee," respectively. Tweedledum and Tweedledee are characters from an English nursery rhyme and also appear in Lewis Carroll's book "Through the Looking-Glass, and What Alice Found There." Both star clusters are quite bright (magnitude 4.6) and may be visible to the naked eye under very dark skies. They are wonderful objects for a small telescope or binoculars. For example, NGC6633, when observed through binoculars, has a distinct triangular outline. ------------------------------------------------------ Used materials: @ https://en.wikipedia.org/wiki/IC_4756 @ https://en.wikipedia.org/wiki/Kasimir_Graff @ https://en.wikipedia.org/wiki/Tweedledum_and_Tweedledee @ https://en.wikipedia.org/wiki/Through_the_Looking-Glass