Pentax xw.

[Timebandit]

     Hello. This week I have acquired some Pentax XW eyepieces. Due to the poor weather conditions i have not been able to try them at night so far(way to much cloud cover). As these are my first Pentax eyepieces my knowledge on them is limited . So while I am twiddling my thumbs waiting to get the pentax in the scope in the night skys. I was wondering with the fountain of knowledge out there if you could please give your views on the pentax, good points , bad points ,were they designed for frac or reflector, what targets are they best on , et ,et anything which will give me a useful background  to them and how to get the best out of the eyepieces. By the way I have the xw 7, xw10

Thanks, and I hope you approve of the new purchases to my eyepiece case   

[Roy Challen]

Pentax make some of the finest eyepieces known to mankind, the XW's are basically orthoscopics with larger field of view and better eye relief.

I believe they were originally designed for spotting scopes but I could be wrong.

Envious approval granted;-)

[John]

My history with Pentax XW's goes back quite a few years when I was loaned the 10mm by FLO to compare it with the Nagler T6's that I was using at the time.

Rather to my surprise, the XW proved to be a gem of an eyepiece. Despite it's smaller FoV the XW had a sharpness, clarity and control of light scatter that was slightly better than my beloved Nagler. That made me think !

In due course I acquired the 5mm and 3.5mm XW's for high power viewing and found them excellent as well. More recently I've added the 7mm and 10mm XW's to complete a small set of them.

I liken them to wide field orthoscopics (as Roy obviously does !) but with loads of eye relief and a really large welcoming eye lens. Very comfortable to use and with very high levels of optical performance despite having quite a number of lens elements and having been originally designed for spotting scopes rather than astronomical use (apparently).

I do have Ethos eyepieces that cover the same focal lengths and I'm still unsure which I prefer to use - maybe it depends on my mood !

The 30mm and 40mm XW's are in the 2" fitting and out of production now. When they do appear on the used market the price seems to have hit around £400+ now which is more than they used to cost when new I think.

The only XW's I've been a little wary of are the 14mm and 20mm because they have quite a bit of field curvature apparently.

Overall superb eyepieces and as good as an SWA eyepiece can get really.

PS: I've used them in a wide range of scopes from slow maks to fast newts and they behave really well in all of them. With high light transmission they a great deep sky eyepieces but also control light scatter well so do a great job on the moon and planets too. Really good all round !

 

[faulksy]

hi timebandit, i love the xw thats why i wanted to buy them of piggy or you. they are excellent as said ortho with 70*. some cant get on with them though, eye placment is hard and they get blackouts but you do get used to them. your very lucky owning them and john

[John]

One additional thing, unless you wear glasses when observing, you will probably find that the best position for the eyecup section of the eyepiece is towards the top end of it's travel. I found that I got quite a few blackouts and some kidney beaning when I initially used the XW's but that was because I did not read the instructions which make it clear where the eyecup needs to be for people like me who don't wear glasses. Should have read the instructions !

[michael.h.f.wilkinson]

I have three XWs (5, 7, and 10 mm), and they are superb. Excellent eye relief, very comfortable, very low degree of distortion, very, very sharp. The Delos range is similar. I have the Delos 8mm, which can be made parfocal with the XWs with a simple ring to fill the gap between 10 and 7mm, which is a bit of a jump in planetary viewing

[alan potts]

Take notice of John's answer it is bang on the money. I have had a few of the shorter XW and found them excellent though I am a TeleVue fan and can't resist the black and green trim. In truth you are not going to find anything much better though I have read the Delite range, albeit with a smaller field are a tad better, but you are going to hard pressed to see it on anything but the best nights.

Alan