Next Steps Eyepiece Kit Reviewed

Ralph Bell took home a set of three eyepieces from Guan Sheng Optics (GSO) and gave them a thorough test against his own favourites. The eyepieces were chosen to complement the 25mm and 10mm eyepieces supplied with many telescopes such as the Skywatcher range. He found them to be very good, especially considering their price, so we are offering them as an ideal next purchase for anyone who has a Skywatcher or similar telescope. Together with a sturdy case with spare capacity for your existing eyepieces we call it the 'Next Steps Kit'.

One of the eyepieces has a two-inch barrel to give a very wide field of view at low magnification. This makes our Next Steps Set stand out from typical eyepiece packages and enables you to make the most of the two-inch focuser on your telescope.

If you would like to know more about the eyepieces please read Ralph's report below :-

Ralph's Report

Eyepieces Included in the Next Steps Set :-

• 30mm (68 degree field-of-view, 2" barrel)
• 15mm (52 degree field-of-view, 1.25" barrel)
• 6mm (52 degree field-of-view, 1.25" barrel)

The tests were carried out on 14th April 2008; the temperature was 4ºC and there was an 8-day-old moon in the sky with excellent seeing.

One thing I have wanted to do for a long time for those customers who have bought 6” and 8” reflecting telescopes from Green Witch is to come up with a set of eyepieces to complement the 25mm and 10mm eyepieces that come supplied in the box. Because the Skywatcher has superb optics, much better than you might expect for the price, I wanted to see if the GSO eyepieces matched them for quality.

The first telescope I used for testing is an Orion Optics 300mm f4 on a dobsonian mount, with a very accurate eighth-lambda mirror. The second is a William Optics 80mm f6.9 Fluorite Refractor on an EQ5 mount. The f4 reflector with its fast focal ratio is a severe test for most eyepieces; if the edge of the field is reasonably sharp the eyepiece has done well. The f6.9 refractor was chosen for it’s superb contrast and very sharp star images across the whole field. Both scopes are Apochromatic so any chromatic aberration detected would be in the eyepiece and not in the telescopes.

Thus equipped I set off into the night with the 3 GSO’s and Reggie and Ronnie (2 cats) for company.

The 30mm 5-element 68º fov 2” entered the focuser of the 300mm first. M81, M82 two galaxies in Ursa Major occupied my left eye for a good ten minutes before I remembered why I was out there, first impression very good, contrast was good, nice black sky with both galaxies standing out well with tiny field stars, one being a little on the yellow side. The double cluster the next target, again a good view with the small older red stars standing out like a warning to the others, one day you too will grow to be a red giant like me!

This 30mm 68º performed better than the 80º 30mm Moonfish, both in contrast and sharpness across the field. Being a little soft at the edge (it is an f4 scope) was its only downfall; this situation was redeemed in the f6.9 refractor with only a very small fall off at the edge.

Next was the 15mm plossl 52º fov 4-element, over to the moon, excellent definition, the whole moon sharp from pole to pole, very crisp indeed, almost cut my eyelashes it was so sharp.

The edge of the field had a small amount of chromatic aberration but this did not detract from what was a stunning view, almost as good as my 15mm Vixen (which cost loads of money!) A quick nudge left had Saturn in view, wonderfully sharp at the centre of the field with its pinprick moons to the sides.

Next the 6mm Plossl 52º fov and back to the moon. Plato in view and 4 craters inside it clearly seen; what a wonderful night! Seeing conditions very good. 1.10am (now the 15th April) detail on the lunar surface was spectacular (I think on a night like this even a jam jar bottom would have given a reasonable view). I used a 6.4mm Meade 4000 eyepiece to check the quality of the 6mm GSO but it was just the same (I paid a lot of money for the Meade eyepiece, yes it came from Green Witch!) Everything was sharp and so much to see. GSO 6mm back in the focuser and over to Saturn. Phenomenal, by now my right eye wanted to see what the left one had been drooling over so I let it have a look, both left and right eyes agreed the view was very good.

These three eyepieces went from one scope to the other for a good half an hour more, until the moon and Saturn set behind the garage. I pointed the 300mm dobsonian at the Virgo cluster, but with a small amount of haze in the sky and a very wet William Optics refractor I knew it was time for bed.

These eyepieces sounded too good to be true, but I found them to be almost as good as the much more expensive ones in my collection. They all have small errors at the very edges, but if like me you want to see what’s at the edge just move it to the middle.

Ralph Bell