![]() ![]() And the 240X provided by the 5 mm eyepiece in the 3X Barlow is too much magnification for an 80 mm refractor. ![]() The 48X provided by the 25 mm in the 3X Barlow works, but is too close to the 40X provided by the 10 mm eyepiece to be of much value. Only the 120X provided by having the 10 mm in the Barlow lens is helpful. With the eyepiece in the 3X Barlow, you would add 48X, 120X, and 240X. The stock eyepieces provide 16, 40, and 80X. So an eyepiece that gives you 40X by itself would give you 120X when placed in this 3X Barlow. The Included 3X Barlow worked reasonably well, but was not well sized for this scope. Shortly after getting the scope, I set these eyepieces aside and went to other eyepieces to avoid this issue. The lack of eyecups is one of those little details that make a big difference. I found myself holding my hands up to try to block the surrounding light to help control these images. As a result, if you are not in a totally dark area, you may get “ghost” images from reflections of street lights, house lights, and such. The eyecup helps to block out stray light from reflecting off the eyepiece surface. They work fairly well however they lack the rubber eyecup that is normally found on eyepieces. They are threaded to accept standard astronomy filters. The eyepieces are not marked, but they appear to be three-element Kellner type eyepieces. Any brand of 1.25” eyepiece will work in this scope. The scope comes with three eyepieces, 25 mm, 16X, 10 mm, 40X, and 5 mm, 80X. This worked much better, and it is easy to swap diagonals. Mine was an inexpensive model that cost about $30. If you want this for astronomy, plan to buy a 90 degree star diagonal. The closer your target is to the horizon, the more the atmosphere you are looking through which will distort the image. My preference for viewing the sky is for my targets to be between 30 and 70 degrees high, so that I am looking through less atmosphere. This provides a much more comfortable angle for stargazing. In the photo below, you can see the 90-degree star diagonal that I purchased separately. The diagonal places the eyepiece at a bad angle so that you have to get on your knees to view things above about 20 degrees. However, the 48 degree angle of the eyepiece makes it awkward to use at night for astronomy when you will be pointing up at the sky. This 48 degree diagonal is optimized for daytime use, making the scope useful as a spotting scope for birding, boats on the water, or other daytime uses. The package comes with a 48-degree correct image diagonal rather than the typical astronomy 90-degree star diagonal. I have not used another scope that has this issue in the focuser. ![]() Fortunately, there is a screw that you can tighten up to address this, but there are no instructions provided to tell you about this. As a result, the optical path gets out of alignment and out of collimation, which distorts the image. While it works smoothly most of the time, the focuser tends to loosen up. You would have to go to a next-level refractor, with ED glass, to eliminate the CA for visual use, and that would cost many times the price of this package.Ī weakness lies in the focuser. As a beginner’s scope, it works fairly well. You tend to get a purplish fringe that is not really there.Ĭhromatic aberration is common to all achromatic refractors, so this is not a specific flaw of this scope. However, as is typical of entry-level achromatic refractors, there is a fair amount of chromatic aberration around bright objects like the moon. The images provided by these eyepieces are quite good. As there are no instructions about how to select eyepieces, you have to discover this on your own. By changing eyepieces, you can vary the magnification. That means it has a lens in the front that gathers light and focuses the light into the eyepiece where you can see the image. The OTA is an 80 mm aperture achromatic refractor. This is what you might normally think of as a telescope. For example, Meade and Celestron typically include instructions on use as well as advice about using the scope, selecting eyepieces, etc. However, if you are new to telescopes or astronomy, this might be a reason to choose another package. For me, an experienced telescope owner, this was not an issue. I will touch on this point throughout the review. Gskyer apparently assumes you know about telescopes. There is a picture card that shows how to put the parts together, but there is no instruction book on how to use the scope. ![]()
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