The Peterson Engineering EyeOpener enhances the performance of long focal length 2" eyepieces on Meade 10" - 14" Schmidt-Cassegrain and ACF telescopes by increasing the eyepiece optical path size as much as 65%. With the Eye Opener, you'll get all of the eyepiece aperture that you paid for while enjoying the full benefit of 2" eyepieces.
As Schmidt-Cassegrain Telescopes (SCT) evolved from 8-inch models to larger-aperture scopes, and as eyepieces evolved from 11/4" to 2", the "Schmidt-thread" couplings used for securing 1-1/4- inch diagonals and eyepieces to telescope backplates remained unchanged. This "Schmidt visual back" supplied with your Meade ACF or LX200 scope has an internal diameter of 1-1/2", and it functions as a 1-1/2 inch-diameter field stop. This field stop effectively limits the performance of your costly 2" optics to the equivalent of 1-1/2" optics. When using the 1-1/2" visual back with Meade's 2" 56mm Plossl (an eyepiece with a full 2" of glass in the nose) you lose 65% of the light to your eye!
Do you think that the large diameter front lens (the "field lens") on your long focal length 2" eyepiece is there for decorative purposes? That's about what happens when you restrict the size of the optical path to that lens with a 1 inch-diameter field stop. Without the EyeOpener(R) you're getting the equivalent of 1" optics. You might as well take a piece of 1/4" wide masking tape and cover up the outside 1/4" of glass on the nose of your eyepiece.
How does the Peterson Engineering Eye Opener mount?
The EyeOpener threads onto a 3-1/4" male thread found on the backplate of 10", 12" and 14" Meade SCT & ACF scopes, providing a full 2" unrestricted optical path. The microfocuser attaches directly to the EyeOpener. Unscrew your 1-1/2" visual back and check it out for yourself. To use the EyeOpener on Meade LX400-ACF scopes and on the older "Classic" Meade SCT's, or to shorten the optical path by eliminating the Microfocuser, you will need the EyeOpener 2" Tube Adapter. The EyeOpener will also allow "Classic" SCT owners to retrofit a Meade #1209 Zero Image-Shift Microfocuser or JMI's NGF-S electric focuser.
Microfocuser mounting thumbscrews are now included with the Eye Opener. Do you recall the old proverb about the added straw that broke the camel's back? Meade's ACF and LX200 scopes are heavy enough to transport without the added 1-1/4 pound weight of the Microfocuser. Replace the 3 mounting set screws in your Microfocuser with these special thumbscrews, and your Microfocuser is readily detachable for scope transport or storage. A plug-type dust seal is also included with the Peterson Engineering EyeOpener.
NOTE: The EyeOpener will not improve your viewing with 1-1/4" eyepieces or with the smaller 2" eyepieces. But it is hugely beneficial when used with the larger 2" eyepieces that give you your widest actual field of view.