7 EASY STEPS FOR PERFECT COLLIMATION
Complete, precision Newtonian collimation can be accomplished by using a collection of 3 unique "Passive" collimation tools and following these 7 easy-to-use steps:
PRELIMINARY ONE-TIME SETUP AT HOME
  1. Center-spot the Primary mirror with the CATSEYETM precision triangle.
  2. Reasonably square the focuser to the OTA/UTA (method of choice).
  3. Using a sight tube (it's f/no preferably matched to the scope's f/no), position and rotate the Secondary mirror to achieve a symmetrically centered "circular" projection of the elliptical Secondary surface.
2" TELETUBE(TM) - WITH PERFECT COLLIMATION
CLICK FOR A CLOSEUP
  1. Adjust the tilt/rotation of the Secondary to center the reflection of the Primary mirror in the Secondary with the center spot location directly beneath the sight tube cross-hairs. (A laser can also be used to facilitate a "preliminary" aim of their Secondary by directing the beam to hit the Primary center.)

FIELD COLLIMATION ROUTINE
  1. Insert a CATSEYE/BLACKCAT XLTM Cheshire and center the reflection of the triangle in the reflection of the Cheshire ring by appropriately adjusting any 2 of the 3 Primary cell screws.
2" BIGCAT/BLACKCAT(TM) w/Perforated triangle centerspot - WITH PERFECT COLLIMATION2" INFINITY(TM) w/Perforated triangle centerspot - PRIMARY TILTED
CLICK IMAGES FOR A CLOSEUP LOOK
  1. Insert the INFINITY XLTM Autocollimator and fine tune the tilt/rotation of the Secondary to first achieve the "dark" view/multiple-image condition and then ultimately to "merge" the multiple images of the center spot.
2" INFINITY(TM) w/Perforated triangle centerspot - WITH PERFECT COLLIMATION 2" INFINITY XL(TM) w/Perforated triangle centerspot - SECONDARY SLIGHTLY TILTED & ROTATED
CLICK IMAGES FOR A CLOSEUP LOOK
  1. Repeat steps 5 & 6 as needed* until BOTH views with BOTH tools are correct ... or alternatively, use Vic Menard's "Carefully Decollimated Primary" Collimation Procedure listed step-by-step Here
APPLICATION NOTES

Either indirect sky light (outside) or a brightly lit wall (inside) can be used to implement the CATSEYETM System, but its strength and real advantage is at NIGHT with the scope set up for observing. In this scenario, a bright red LED light is directed at the Primary and illuminates the reflective surfaces of the CATSEYETM precision triangle and also the reflective ring of the CATSEYE/BLACKCAT XLTM Cheshire.

* Typically only 2-3 iterations of use with a CATSEYE/BLACKCAT XLTM Cheshire and an INFINITY XLTM Autocollimator are required to dimish the detectable axial optical alignment errors which is more than sufficient for maximizing the scope's optical performance - aka "Perfect Collimation".