A famous star with 3 apertures

[John]

I'm having some fun on this warm evening comparing the views of Epsilon Lyrae with 3 apertures:

- 120mm F/7.5 ED doublet (Skywatcher ED120)

- 70mm F/6 ED doublet (Altair Starwave 70 ED)

- 52mm F/17.3 ED doublet (stopped down ED120)

The ED120 makes the split of both star pairs easily of course. The lowest magnification that clearly showed 2 separated pairs tonight was 70x.

The 70mm ED gets both pairs clearly split at 100x and up. Even looked decently sharp, though dimmer, at 200x.

The 52mm ED, rather surprisingly, also managed to split both pairs. Somewhat dimmer than the 70mm and I needed 115x to be sure that I was seeing 4 separate stars but I feel confident that the split of both pairs was made.

Not very scientific but fun all the same 🙂

 

  

[Epick Crom]

Nice report John. This is what amateur astronomy is all about, enjoying ourselves and having fun! 

Wishing you clear skies

Joe

[RobertI]

Nice comparison John, a fun thing to do with your scopes. It’s amazingly clear and transparent out there tonight, but I’m just too tired. 😴

[Franklin]

Was out playing with the Vixen 80mm F/11.4 achromat the other night and viewed Epsilon Lyra amongst other things, all four stars clearly split at x121 using a vintage Vixen 7.5mm Silver-top plossl. A "back to basics" session with a manual GP2 and a few old eyepieces, this 3" achromat continues to surprise me. I must get it side by side with the SD81 some time and make some comparisons.

[NGC 1502]

12 minutes ago, Franklin said:

Was out playing with the Vixen 80mm F/11.4 achromat the other night and viewed Epsilon Lyra amongst other things, all four stars clearly split at x121 using a vintage Vixen 7.5mm Silver-top plossl. A "back to basics" session with a manual GP2 and a few old eyepieces, this 3" achromat continues to surprise me. I must get it side by side with the SD81 some time and make some comparisons.

I would be very interested to hear your comparison 😊

[Mr Spock]

I remember first splitting them some 50 years ago with my 60mm f15 Prinz 550. The eyepiece I probably would have used was a 6mm Kellner at x150. I did have a 4mm orthoscopic, which while sharp , was very dim. I still have those eyepieces.

I still go back to it all these years later. 

[John]

23 minutes ago, Mr Spock said:

I remember first splitting them some 50 years ago with my 60mm f15 Prinz 550. The eyepiece I probably would have used was a 6mm Kellner at x150. I did have a 4mm orthoscopic, which while sharp , was very dim. I still have those eyepieces.

I still go back to it all these years later. 

Albireo in Leo was my first ever double star and that was with my old Tasco 60mm F/13.3. 🙂

I probably thought that exotica like the "double double" was beyond me and my little scope back then 🙄

Mind you, the wobbly tripods that such scopes came with did not help get the best out of them. Put these old long refractors on a decent mount and it's surprising how well they can do, as people are finding out 👍

 

Edited June 16, 2023 by John

[Mircea]

John

I suggest to you to go deeper. I'm sure you will be able to see with the 120mm ED the two ''debillissima'' stars.

''Debillissima'' stars are located between the two pairs in Eps -12 Lyr. They are quite dim so better use high power.

I saw them with my 125mm F/ 6.9 Dobsonian and, recently, a forum fellow member saw them with a 114mm reflector.

 

Clear sky, Mircea

[John]

58 minutes ago, Mircea said:

John

I suggest to you to go deeper. I'm sure you will be able to see with the 120mm ED the two ''debillissima'' stars.

''Debillissima'' stars are located between the two pairs in Eps -12 Lyr. They are quite dim so better use high power.

I saw them with my 125mm F/ 6.9 Dobsonian and, recently, a forum fellow member saw them with a 114mm reflector.

 

Clear sky, Mircea

Thank you for the reminder about those fainter stars - I will look for them the next time I am out 🙂