Continued Fidelity to My Celestron Zoom 8-24 Eyepiece Despite Availability of Alternatives
Breathed-In Thoughts
Dialing in the cosmos, one zoom at a time.
My beloved Celestron 8-24 zoom eyepiece has been my faithful companion for several years now. With this bad boy, the single-focal-length eyepieces barely see the light of day.
Similar to a zoom lens on a camera, this telescope eyepiece offers a range of magnifications - but be warned, not all zoom lenses are created equal. Some are subpar or come with a narrow field of view, leaving me less than impressed.
However, the Celestron 8-24 mm zoom eyepiece has earned my seal of approval. It holds up admirably alongside my Plossl eyepieces, and I haven't found another zoom telescope that outshines it under $100.
Armed with this one eyepiece and a proper Barlow lens, you can replace 4-6 single-focal-length eyepieces and perform feats they couldn't.
Tried and Tested
I've put the Celestron zoom under the cosmic microscope in a variety of scopes. From two 80 mm f/5 refractors to a 203 mm f/5.9 Newtonian, the results were consistently impressive.
In scopes with focal ratios of f/6 or lower, I did notice some aberration on the edges, but nothing to raise a red flag. For eliminating these edge effects, I'd have to step up to a significantly pricier zoom eyepiece.
The Celestron zoom is my top choice for outreach events where I have folks lined up to gaze at the stars. It's a breeze to share the view with multiple people as I hand the telescope over at low magnification, keeping the target in view for longer. They then zoom in to their preferred magnification.
Kids are always thrilled by the zoom effect, contrasting the low-power view of the Moon with a close-up. It always garners a "WOW!"
Magnification Magic
Rather than buying a set of fixed focal-length eyepieces with standard magnifications, the Celestron zoom offers the whole range, with in-between magnifications to boot. Need a 11.5 mm eyepiece? You got it. Craving a 9 mm? Got that too, just rotate the barrel and watch the image.
Focal lengths are marked on the barrel, serving as a reference when making notes for observing reports. Rarely will you even notice the magnification you're using, as the image - not the eyepiece - is what truly matters.
In comparison, single-focal-length eyepieces require you to constantly switch between eyepieces when changing magnification, but the Celestron zoom seems to disappear, allowing you to focus on the celestial bodies.
The 1.25" Eyepiece Barrel Diameter
With most modern telescopes accepting 1.25" eyepieces, the Celestron zoom fits them all. If your telescope uses a 2" eyepiece, there might be an adapter for accepting 1.25" eyepieces, so you're good to go.
Bear in mind that some older scopes use the 0.965" eyepiece size, but these are now obsolete. If you have one of these scopes, the Celestron zoom won't fit, but affordable adapters can enable the use of 1.25" eyepieces. The only catch is that you might experience trouble bringing a 1.25" eyepiece into focus, but it's worth a shot.
A FOV of Forty to Sixty Degrees
The apparent field of view (AFOV) specification from the manufacturer helps determine the amount of sky you'll see through the eyepiece. The Celestron Zoom provides a starting 40-degree AFOV at the 24mm setting, gradually expanding to 60 degrees at the 8mm setting.
Compared to other beginner telescope eyepieces, such as Kellner and Modified Achromat, which typically offer around a 40-degree AFOV, and Plossls, with about a 50-degree AFOV, the Celestron zoom runs a bit narrower to wider.
At higher magnifications, the widening of the AFOV on the Celestron zoom is a bonus; you get a wider AFOV at a higher 8mm setting where it's beneficial. You won't find this in many other zoom eyepieces at such an affordable price.
Eye Relief for Glasses-Wearers
The 15 to 18mm eye relief specification on the Celestron zoom is essential for everyone, especially glasses-wearers. Eye relief is the distance you need to position your eyeball from the top lens to see the full field of view. While I typically remove my own glasses for observing, glasses-wearers may need more eye relief to see the whole view.
Weight and Balance
At 8 ounces, the Celestron zoom is heavier than the typical Kellner, Modified Achromat, or Plossl eyepiece, which usually weigh between 3 and 5 ounces. From my experience, it doesn't pose an issue in 80mm scopes, but on very small scopes, the weight might throw off the balance. Keep an eye on this, but I doubt it'll be an issue for you.
Measuring Magnification
To illustrate, let's look at two typical eyepiece focal lengths: 25mm and 10mm. If your telescope has a 1000mm focal length, the 25mm will offer 40x magnification, and the 10mm will provide 100x. The Celestron zoom offers 41.67x to 125x, with all in-between magnifications as well.
In many cases, this magnification range will cover the full range of your scope's capability. If you have a larger aperture scope, you might match the zoom to a 3X Barlow, giving you 125x to 375x magnification.
Still Got You Covered: Fixed Focal-Length Eyepieces
For specific targets that work best at low powers or require a wider field of view, I still recommend a low-power wide-view eyepiece in the 28 to 40mm range. Feel free to use single-focal-length eyepieces along with the zoom as well.
Why Go for a Zoom?
- A seamless transition between magnifications: With a zoom, the eyepiece seems to disappear as you move from lower to higher magnifications.
- Splitting double stars becomes a breeze: With the Celestron zoom, you can watch a single star resolve into two or more stars as you rotate the barrel; there's no question that you've split it.
- Filter swapping is eliminated: With the zoom, one filter serves over a wide range of magnifications; no need to screw and unscrew eyepieces for different magnifications.
- Tackle turbulent atmospheres with ease: The zoom allows for smooth, small magnification changes, ensuring you're always working at the optimal magnification for the target when "seeing" is poor.
- Readies your eyepiece case for lighter packing: With the Celestron zoom taking the lead in terms of versatility, your eyepiece case can be simplified.
In summary, the Celestron 8-24 zoom is a top-tier performer in its price range. A solid choice for both beginners on a budget and those seeking to expand their magnification options. While other, more expensive zoom eyepieces are available, I find myself consistently impressing the cosmos with my dependable Celestron zoom.
- The Celestron 8-24 mm zoom eyepiece is ideal for outreach events, as it allows multiple people to easily observe the stars, even the moon, by changing the magnification with a simple turn of the barrel.
- In astrophotography, gadgets like telescopes and eyepieces, such as the Celestron 8-24 mm zoom, leverage technology to capture the wonders of the cosmos, one zoom at a time.
- For beginners, the Celestron zoom eyepiece offers a wide field of view, ranging from 40 to 60 degrees, which is beneficial for observing celestial bodies like the moon.
- When paired with the right technology, such as telescopes and eyepieces like the Celestron zoom, refractor telescopes can enhance the experience of hobbyists, enabling them to explore different magnifications and feats that single-focal-length eyepieces couldn't.
