EASYTESTER II®

The EASYTESTER II is an eyepiece like device that allows the owner or user of any type of telescope to quickly determine the current condition of the collimation and assist in correcting it if necessary.

Anyone who has ever purchased or built a telescope has experienced that uncertain feeling of not knowing whether those un-textbook-like images are the fault of the optics, faulty adjustments or just seeing conditions.

The EASYTESTER II is technically known as an autocollimator. It is "auto" in the sense that once perfect collimation is achieved, the reflected image goes dark and leaves no doubt. It consists of a small perforated mirror mounted in an eyepiece.

The drawing at the left represents the view when looking through the autocollimator. The outer circle is the aperture at the end of the scope. The dot in the center of the auto collimator mirror is the reflection of the perforation at the eye end. The spot to the left represents the dot on the center of the primary in a slightly out of collimation system.

Adjustments are made until the two spots line up or all of the reflected circles are concentric. When the precise point is reached, the AC mirror darkens and alignment is perfect.

If the primary does not have a central spot, it can be added with a marking pen and as it is blocked by the secondary, it has no effect on the image. The spot is not necessary for autocollimation but it greatly simplifies the rough alignment.

For information on our companion RONCHI TESTER go to: EASYTESTER

EASYTESTER ................................. $29

EASYTESTER II..........(1.25")............ $25

Like all JSP products, the EASYTESTER carries a lifetime warranty.

The EASYTESTER can be purchased directly from our factory at the above prices but payment must be in the form of check, money order or PayPal.

If you prefer to use a credit card, you can do so by ordering from the following dealers:

ADIRONDAK VIDEO ASTRONOMY: 877 348 8433, (NY)...518 812 0025

SCOPE STUFF (Texas)...512-259-9778

SHUTAN CAMERA... 800 621 2248, (Illinois).... 312 332 2000

la maison de l'Astronomie (Paris) 01 42 77 99 55

Stargate Telescope Supplies (Australia) +61 (049) 43 8580

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