1. What to do to a Dob Presentation by Keith Rickard 27 September 2012

3. Cleaning the mirror Don’t!

4. Cleaning the mirror Yuk!

5. Cleaning the mirror What do you need? 1.Tap water 2.Washing-up liquid 3.5 Litres of distilled water 4.Cotton wool – preferably surgical 5.Vessel large enough to take the mirror 6.About an hour of your time

6. Removing the mirror Lay the telescope on a flat surface.

7. Removing the mirror Locate the tube fixing screws – note an alignment mark for replacing the cell Alignment mark

8. Removing the mirror Gently withdraw the mirror cell

9. Removing the mirror

10. Locate the mirror fixing brackets

11. Removing the mirror Unscrew and remove the brackets

12. Removing the mirror Carefully remove the mirror from its cell

13. Washing the mirror Fill the trough with tap water

14. Washing the mirror Put in a sparing amount of washing-up liquid

15. Washing the mirror Swish the water around to get an even spread of soap

16. Washing the mirror Gently place the mirror in the water and leave to soak for about 15 mins

17. Washing the mirror The mirror should be about 2cm below the surface

18. Washing the mirror Gently swish the water across the water for about 5 mins

19. Washing the mirror Use only the weight of a swab of cotton wool to remove stubborn marks

20. Washing the mirror Remove the mirror while getting ready to rinse it

21. Rinsing the mirror

22. Use distilled / de-ionised water. This 5L container cost £3.99. Using this water will mean no marks will be left on the surface of the mirror when it is left to dry

23. Rinsing the mirror After rinse and drying the trough, empty the container into it

24. Rinsing the mirror Replace the mirror and swish the water over it

25. Drying the mirror

26. Stand the mirror on its end on a towel and let it dry naturally

27. Collimation – Newtonian Telescopes

28. This guide describes: Technique for visual use only Using a laser collimator Why collimate? By aligning optics as well as possible improves the performance of the telescope. Newtonians notoriously fall out of collimation very often.

29. Collimation – Newtonian Telescopes

30. Before starting… MAKE SURE THE OPTICAL TUBE IS HORIZONTAL You don’t want to drop anything onto the primary mirror!

31. Collimation – Newtonian Telescopes What needs adjustment? 1) Radial position of the secondary mirror

32. Collimation – Newtonian Telescopes Secondary sighting tool A Kodak 35mm film pot is ideal for this purpose!

33. Collimation – Newtonian Telescopes What needs adjustment? Insertion of the secondary mirror Orientation of the secondary mirror Left image shows an insertion and orientation adjustment is required. Right image shows the correct position.

34. Collimation – Newtonian Telescopes What needs adjustment? Collimation of the secondary Centre spot on primary is required

35. Collimation – Newtonian Telescopes What needs adjustment? Collimation of the secondary

36. Collimation – Newtonian Telescopes What needs adjustment? Collimation of the secondary

37. Collimation – Newtonian Telescopes What needs adjustment? Introducing the Laser Collimator

38. Collimation – Newtonian Telescopes What needs adjustment? Collimation of the secondary

39. Collimation – Newtonian Telescopes What needs adjustment? Collimation of the secondary

40. Collimation – Newtonian Telescopes What needs adjustment? Collimation of the secondary

41. Collimation – Newtonian Telescopes What needs adjustment? Collimation of the secondary

42. Collimation – Newtonian Telescopes What needs adjustment? Collimation of the primary mirror

43. Collimation – Newtonian Telescopes What needs adjustment? Collimation of the primary mirror Adjustment screws Locking screws

44. Collimation – Newtonian Telescopes What needs adjustment? Collimation of the primary mirror

45. Collimation – Newtonian Telescopes In summary: Generally, only the use of the laser collimator is required That means collimating the secondary & primary mirrors only Generally, I find the secondary needs most attention The process takes 1 -2 minutes

46. Digital Setting Circles They aid rapid pointing of the telescope and to allow the user know where the telescope is pointing This set-up is a Push-To arrangement Encoders are placed on each axis Encoders are connected an interface box The interface box is then connected to a computer Software on the computer, say a planetarium program, gives the user access to a database of objects to find, etc.

47. Digital Setting Circles The Altitude Encoder

48. Digital Setting Circles The Azimuth Encoder

49. Digital Setting Circles The Interface Box The Dave Ek Digital Setting Circles printed circuit board - $24.00

50. Digital Setting Circles The Interface Box

51. Digital Setting Circles The Interface Box

52. Digital Setting Circles The Interface Box

53. Digital Setting Circles The Interface Box

54. Digital Setting Circles The Interface Box connected to a PC serial port

55. Digital Setting Circles The Interface Box connected to a Bluetooth serial adapter

56. Digital Setting Circles Software – Android Smart Phone Sky Safari Plus (cost ~£8.00) Massive database of different types of objects Contains 2.5 million stars – excellent for zooming in to see the star filed as seen in the eyepiece – makes spotting the object more easy. Easy telescope control using

57. Digital Setting Circles Software – PC Planetarium The software which use ASCOM drivers will work Sky Map Pro does

58. Digital Setting Circles

60. The End