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Posted by Mark Gemmell   12/14/2022 04:47PM



I owned and used a set of four of them for a short while. These are priced really well and you won't empty your wallet if you want to delve into the 100 degree world of eyepieces. I owned the 20mm, 13mm, 9mm and 7mm versions. I really liked them all, but my favourite was the 9mm. I will start with the 20mm and work my way up in focal length. I used all four of them with a 2" GSO coma corrector and a 28mm spacer in between. I found this setting optimal for coma correction with all of them. I parfocalized all of them so that spacing did not have to be changed, plus they were always in focus when switching eyepieces, unless the seeing changed, and it would change as I used them over the course of the night. These were used in a 10" Orion F/4.7 Reflector. Proper cooling and collimation was always set up first, as always. I also used two 2" barlows with the 9mm and the 7mm versions.

20mm APM XWA

This was my finder eyepiece and also used for wide open clusters and nebulae. I tried it without the coma corrector and it was unimpressive. A coma corrector is a MUST when using this eyepiece at F/4.7. Without the coma corrector, the outer half or so looked quite aberrated. I wouldn't recommend it, unless using with an O-III or Narrowband filter. The weight alone of this eyepiece is 1.5 Lbs. Not too bad, IMO. When adding the GSO coma corrector, the weight is 2 Lbs / 4 Oz. My scope still handled it well. I just left the coma corrector on my scope at all times, which was much better and stars were points instead of "Mellennium Falcon smears", lol. Over time I felt that the weight of 2 Lbs / 4 Oz to be a bit much, so I slowly started selling the APM 100's in favour of the Baader Morpheus eyepieces. More on that later. The one thing I did really like about the 20mm APM 100°, was how nicely it played with filters. No reflections whatsover. It also had extremely easy eye placement over other eyepieces I have used in the 20mm range. I found that it was "just do-able" with glasses also. I've read that the 20mm APM 100° is very close in performance to the 21mm TeleVue Ethos, and at a fraction of the cost. I would recommend buying this over the Ethos if you wanted to try out 100° eyepieces. This way, if you are not satisfied, you won't be out a lot of money. Eventually, I was able to compare the 20mm APM 100° with a 21mm TeleVue Ethos with a friend, and both of us agreed that eye placement in the 20mm APM XWA was easier to hold.

13mm APM XWA

I actually bought this one first to try them out. I had sold a 12.5mm Baader Morpheus to fund for it. The 13mm is a really nice Deep Sky eyepiece, but forget about wearing glasses with this one. The eye relief is just too short to take in the entire FOV when viewing through it. There really is no point in buying any eyepiece if the eye relief is too short and some of the FOV gets cut off. They are just not meant to be used this way. Not recommended if you need to wear glasses while viewing with this one. I tried barlowing with this and it barlowed really well. The weight of the 13mm is 1 Lb / 1 Oz. Not too bad by itself, but this one also needed the CC to work at optimal sharpness. The weight with the GSO CC, is 1 Lb / 13 Oz. One thing I forgot to mention about, was that these 100 degree eyepieces offer you a really wide AFOV and I found it was really nice for deep sky. You get good magnification, and a really wide AFOV to go with it. 100 degree eyepieces are really addictive for deep sky! Light transmission for this and the 20mm was excellent as well. The field stops in the 20mm and 13mm were sharp looking to my eye also. Eye placement in the 13mm was easy to hold. No blackouts or kidney beaning was present. Same goes for the 20mm APM .


This one is my favourite, but I really did like the 20mm XWA a lot as well. The 9mm was used quite a bit on smaller Deep Sky objects and planets with a 2 " barlow lens. It had fairly decent eye relief for being a 9mm eyepiece, if you do not need to use glasses. The huge 100 degree AFOV these offer is really nice and very addictive. I found it hard going back to 68° at first because the apparent field of view these show is just so BIG. The 9mm APM XWA and the 2" barlow lens gave me 240x and 340x depending on which barlow lens I used. At the time I was using a 2" Orion barlow lens, (as shown in the picture I have provided), which had the lens detached at the time I took the pic. The other barlow lens is a 35mm extension tube and I would use the lens of the barlow on this too. The Orion gave me about 2.2x magnification and the 35mm extension tube + lens gave me about 1.85x magnification. I would often use 240x on Jupiter and I would use 340x on Saturn if the seeing allowed. I mostly use 300x on Saturn and sometimes 280x. The weight of the 9mm alone is 1 Lb. With the GSO coma corrector it is 1Lb, 12 Oz. There was no blackout problems, kidney beaning or anything weird going on when using this eyepiece. It has super easy eye placement. Planets were very sharp and contrasty. I could see a lot of detail on Jupiter and Saturn. Eye relief on this, like the 13mm, is not glasses friendly. You really need to use this without glasses to get the full effect. In order for me to get in closer, I used the older Baader Morpheus eyecups and just left them folded in the down position. When I used nebular filters, I just cupped my hands around the lens to make it look darker and keep any stray light out. Like the 13mm version, the 9mm has a fairly sharp looking field stop.


I bought this one last after selling a 6.5mm Baader Morpheus. Like the 9mm, the 7mm was also excellent. It was a lot like the 9mm in every regard. I used this on globular clusters and smaller Deep Sky objects. It gave me 170x when used alone. It gave me just over 300x when used with the shorter 2" barlow and close to 400x with the Orion barlow. Really nice for splitting close double stars or for looking at really small planetary nebulae. I also used it on the planets as well. I found that it was nice to have the really big AFOV as it gave me more drift time as I do not use tracking. These eyepieces only lack in eye relief, so I eventually sold all four of them and I gravitated back to the Baader Morpheus, (12.5mm, 9mm and 6.5mm). I still use a 21mm Baader Hyperion with a 14mm fine tuning ring as my lowest power. Then I will be getting another 30mm APM UFF or a 30mm Pentax XW, or maybe even the 23mm Pentax 85 degree! (My wallet is feeling the dent already, LOL).


The APM 100 degree eyepieces are excellent quality eyepieces. They are not as expensive as the TeleVue Ethos, and you won't kill your wallet if you buy the entire set. They are not glasses friendly, but they are excellent if you don't need to use glasses. They are also not that heavy as compared to others. I only sold mine to go back to the Baader Morpheus because sometimes I do use glasses when sketching or reading the controller on my 10" Orion Intelliscope and I don't want to keep on removing the glasses and putting them back on again. Another good thing about longer eye relief eyepieces, is that they do not fog up as fast as shorter eye relief eyepieces do in colder weather or really damp conditions on summer nights. I found when going back to the Baader Morpheus eyepieces, that the AFOV did not feel restricted compared to the 100° APM XWA's.
I hope you liked this review. Please feel free to add anything I may have missed and thanks to Astromart for allowing me to type up this review.

Clear Skies !!!