Product Description
Most conventional illuminated reticle eyepieces have a short focal length and limited eye relief, which can make for uncomfortable viewing, particularly if you wear eyeglasses. In comparison, the Astro-Tech #AT24IL has a long 24mm focal length for a wider field that makes it easier to locate guide stars. This virtually eliminates the need to swap out a high-power illuminated reticle with a lower power eyepiece to locate or center objects.
Its very long 20mm eye relief and soft roll-down rubber eyecup make it very comfortable to use, whether you wear glasses to observe or not. You can use this Astro-Tech 1.25" eyepiece with any make or model of telescope or off-axis guidescope.
The eyepiece reticle has a single etched crosshair precisely centered in eyepiece field of view for accurate results. A ribbed ring at the top of the eyepiece rotates to focus the crosshairs sharply to match your eyesight. The five-element optical system is fully multi-coated on all air-to-glass surfaces with high transmission anti-reflection coatings for bright, crisp views. The edges of the lenses are blackened for high contrast. The barrel is threaded for standard 1.25" filters.
The metal-body cordless red LED (light emitting diode) crosshair illuminator has a rotary on/off switch with an integral brightness level control. Two supplied 1.5V watch/camera/calculator button batteries will power the illuminator for many hours of use. The supplied batteries are model GPA76, but you can also use the Duracell, Maxell, National, Panasonic, Sony, or Toshiba LR44; the Eveready or Philips A76; etc. When replacing batteries, be sure the battery - signs face the LED portion of the illuminator and the + signs face the on/off switch.
Please note: While the manufacturer normally supplies batteries at no cost with this product as a convenience, the battery charge or useful life is not guaranteed. The batteries may arrive with their charge depleted or very low. In such a case, you will have to purchase replacement batteries locally, as battery life is not covered by the manufacturer's warranty.
Tech Details
| Eye Relief | 20mm |
|---|---|
| Field of view | 50 |
| Focal Length | 24mm |
| Weight | 4 oz. |
| Warranty | 1 year |
Reviews
The illuminator has two chambers that open by unscrewing the barrel, one for the batteries and one for the electronics. The instructions say not to open the electronics chamber or you'll damage the electronics and void the warranty, but that chamber doesn't close securely and the dimmer rides on its threads. It seems to open every time you turn the dimmer to "off" due to the detent between min-brightness and off. As a result, the brightness of the illuminator jumps around and isn't a smooth gradient from min to max brightness.
Making it easy and inevitable to do something that'll void the warranty rubs me the wrong way, especially since this issue could have been easily remedied at the factory with some red Loctite or a set screw. (Posted on 1/15/2024)
Price is good. (Posted on 7/22/2019)
