RUSSIAN TELESCOPES AND BINOCULARS WEB SITE
HOW TO COLLIMATE A TAL KLEVSTOV TELESCOPE
However, ex-factory collimation seems to be hap-hazard even though star testing shows near perfect alignment to 750X or so. A check with a laser collimator through the star diagonal will often show shortcomings.
1. Remove diagonal from the OTA.
2. Mount laser collimator in the diagonal.
3. Place a tissue or Greaseproof paper over the opposite end of the diagonal & check to see if the beam is concentric with the aperture.
If not, the star diagonal ideally needs adjustment. The mirror inside is fully adjustable, but any changes made may affect the range of focus in the focuser, particularly if Orthoscopic eyepieces are used. It appears the diagonal is set to suit the alignment of each telescope when assembled at the factory & cannot be interchanged with other scopes. The OTA can be checked for alignment, but a special adaptor & light tube need to available to do this also using a laser collimator.
IMPORTANTLY no adjustments should be attempted to either the star diagonal or the OTA unless all of the equipment below is available. At this stage it may be better to leave well alone as the advantages of the small improvements in optical performance may not be worth the effort until the fairly complex procedure of adjustment & construction of the telescope is fully understood. Study the construction using diagrams in the Owners Handbook or on the TAL website. On-axis performance will not change significantly, but it will maximise the usable FOV which is very limited in this type of telescope (approx .8 Deg.).
1. Light Tube
2. Laser Collimator
3. 7mm & 9mm Socket & or open spanners to suit adjusting screws front & rear of OTA
4. Collimating adaptor (11mm dia, x .5mm pitch – 1 ¼” I.Dia.) Available from us for $65AUD
5. Greaseproof, tracing paper.
The aim of this exercise is to bring all components of the OTA on axis using a Laser Collimator from the Star Diagonal through the focuser Secondary & Primary Mirrors before doing a final Star Alignment to complete the process.
1. ALIGNMENT OF THE PRIMARY MIRROR
1. Remove Star Diagonal from the Focuser.
2. Mount the OTA securely on its equatorial mount.
3. Remove the soft plastic cover from the focuser plate on the rear end of scope to expose the 6 Primary mirror adjusting screws. (Fig.5)
4. Remove the plastic cap that covers the spider centre to expose the 6 Secondary mirror adjusting screws. (Fig.6)
5. Unscrew the 6 Primary Mirror adjusting screws by 2 turns to loosen the Primary Mirror.
6. Carefully screw the Collimating Adaptor into the centre of the secondary mirror mount so as to not cross thread it. (Fig.2)
7. Mount the light tube into the collimating adaptor & clamp.
8. Mount the laser collimator into the focuser & clamp. (Fig.3)
9. Turn on the laser (The secondary mirror has a non-coated centre enabling a laser beam to pass through)
10. Lightly tighten 3 of the Primary Adjusting screws so as to allow the laser beam to pass through the sighting hole of the Light Tube & then tighten the remaining 3 screws, maintaining the position of the laser beam through the Focuser. OTA & out via the sighting hole of the Light Tube.
2. ALIGNMENT OF THE SECONDARY MIRROR
1. Mount the Light Tube in to the Focuser & clamp.
2. Mount the Laser Collimator into the Collimator Adaptor & clamp. (Fig.3)
3. Turn on the Laser.
4. Lightly tighten 3 of the Secondary Adjusting screws so as to allow the laser beam to pass through the sighting hole of the Light Tube.
3. ALIGNMENT OF THE STAR DIAGONAL
1. Mount the Laser Collimator into the Star Diagonal & clamp.
2. Remove the cover to expose the mirror & its 4 adjusting screws of the Star Diagonal.
3. Place Tracing paper or Greaseproof paper over the open end of the diagonal.
4. Turn on the Laser Collimator. (Fig.4)
5. Adjust screws evenly to place the beam showing on the tracing paper in the centre of the mounting tube of the Star Diagonal.
6. Remove the tracing paper & mount the Star Diagonal back into the Focuser & clamp.
7. Mount the Light Tube in the Star Diagonal & clamp.
8. Mount the Laser Collimator into the Collimating adaptor & clamp.
9. Turn on the laser & adjust the screws in the Diagonal so as to pass the laser beam through the sight hole in the Light Tube.
10. Repeat steps 2. 1 – 4 & 3. 1 – 9 until no more adjustment is necessary.
The telescope will now be roughly aligned but these adjustments may have altered the position of the focuser where the eyepieces need to come to focus. Try to focus all of the eyepieces that will be used with that telescope. If one or more wont come to focus at infinity, the position of the Secondary Mirror will need to be altered relative to the Primary Mirror. This can be achieved by adjusting the Hollow screw inside the spider centre.
4. ADJUSTING THE FOCUSING POSITION OF THE DRAWTUBE
1. Loosen three of the Secondary Adjusting Screws.
2. Turn the Hollow screw 1/8 turn clockwise if the Draw tube in the focuser wont rack in far enough for focus & Anti-clockwise if it wont rack out far enough. Small amounts of adjustment here will make large changes to the position of the drawtube to gain proper focus.
3. Keep making adjustments so that your eyepieces come to focus at infinity with the Focuser half way out.
4. Retighten the Secondary Adjusting Screws.
Double check to make sure that with the Laser collimator mounted in the Star Diagonal, the beam will pass through the OTA & pass out through the Light Tube which is mounted into the Secondary Adaptor. If not, make adjustments to correct.
5. STAR ALIGNMENT
Final star alignment should be carried out at night on a bright star, starting with a 10 – 20mm eyepiece and progressing to as high power as able on the night by adjusting the Secondary Mirror. Instructions for this can be found in the Owners Handbook or on the Web.
NOVOSIBIRSK RUSSIAN TELESCOPE
Australian Residents Please Call (08) 8381 3188
|SITE MAP & SEARCH SITE|