Last night my new telescope, the TAL 100 RS, a four inch refractor (achromatic) got its first light. I mounted the tube (4.4 kg) on the EQ 6 and started with Vega. I immediately noticed a few differences with my TAL 200K. The field of view is twice as wide with the 100RS. My 200K has a maximum field of view of 46.5' with the 32mm Plossl. The TAL 100 RS in combination with the same eyepiece has a field of view of 93' or 1.5 degrees. What I found really striking is that the 100 RS produces sharp, pinpoint images of stars. In the 200K the stars are brighter, but not really like pinpoints. Another difference, and that's the downside of the refractor, the 100 RS showed a bluish glow around Vega at high magnifications. However, the Baader fringe killer reduced this glow with 75 percent. The good news is that you see this bluish glow only around very bright objects.
After Vega I went to the double-double or Epsilon Lyrae, and what I got was a real surprise. Normally in my 200K at nights of good to excellent seeing, I can split the double-double at 100x, but normally I have to go to a higher magnification to get a clear split. With the TAL 100 RS I got an easy and clear split at 100x (10mm eyepiece) and both stars seemed elongated at 80x. This telescope looks very promising for double star observation.
From the double-double I moved on to Albireo (Beta Cygni), and again the beauty of the image struck me. At a magnification of 33 (32mm Plossl) this is a grand sight. The colour contrast between the blue and yellow-gold components is stunning through this telescope. I have been looking at Albireo since 1978 but at every possible occasion I return. It is definitely one of my favourites.
I finished the night with an accidental discovery. I was scanning the area southwest of Gamma Cygni, when I stumbled across a group of stars that looked like a propeller. Three arms that spiral out from a brighter star. I knew I had seen it in a book, but I could not identify it at the telescope. I knew it was one of Phil Harrington's asterisms in his book "The Deepsky". Today I looked it up and found it on page 198 (with an eyepiece impression). It was STAR 26, the Red-Necked Emu. It is called that way because, when you look at it in the right angle, you can see an Emu, with legs, tail and neck. All stars are blue, only in the Emu's neck is orange-red star to be found.
My overall impression of this telescope is very satisfying. I bought it because with my TAL 200K I see the Sun and Moon crammed into my eyepiece, almost filling the whole field of view. With this new telescope I hoped to get a view of both objects, with some space left around them. After this first night out I know for sure that this telescope will be used not only for solar and lunar observations, but also for double stars, asterisms and open clusters! I will keep you updated.