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Originally Posted by Suzy
When I was out observing last night using my favorite eyepiece -the XW10- and enjoying the comfort and fov so much, I felt saddened that I wasn't going to get the same again in the 14. I have to think long and hard whether to put up with field curviture on this or not (as a compromise).
Dave: Have you tried the XW14 on a fast scope (under 5?) I'd be interested to hear your view points. If you have used this ep on a fast scope, how much did the field curvature (stars bloating about 20-25% on edge of fov) annoy you? Thank you for your input.
John B: If I may bother you again, can I direct the same question to you as I have asked Dave? Thanks John.
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Hi Suzy,
Here is a post I replied to on Cloudy Nights a few days ago which addressed this specific issue
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Does anyone have experience with the Pentax 14XW at f4.5 while using a Paracorr? I've read that there's lots of field curvature without a Paracorr, but I haven't read any detailed reports of its performance at short focal ratios with a Paracorr. Comments from anyone who has used that combo would be much appreciated!
Hi,
I have the 14mm Pentax XW which I use with and without a paracorr in both my F4.5 scopes, which have premium mirrors (see signature panel). I also have a 13mm ETHOS. The field curvature without the paracorr in both scopes is evident and noticeable. It doesnt bother me because I obviously have good adjustment for this with my own eye, but I can appreciate it would bother a number of people. The paracorr combined with the 14mm XW improves the view immensely, to the point where to my eye, it is "almost" perfectly sharp to the very edge of the FOV. I prefer to use the 14mm XW with paracorr than I do to use the 13mm ETHOS because of the greater comfort of the 14mm XW.
I have also used the 14mm Denkmeier extensively and if I was starting out again this is the eyepiece I would be buying at the 14mm focal length.The 14mm Denkmeier has no faults. It does everything exceptionally well, including optically in every respect and comfort and eye relief. Only downside is the AFOV is 65 deg. Keep in mind that I am happy with the 70 deg AFOV of the XW's and the 100 deg AFOV of the ETHOS line isn't a major determining factor for me.
Cheers,
John B
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The 14mm Pentax XW at F5 is good, it has all the niceties of the XW line but the field curvature is evident without a paracorr.
Let me reminisce over my experince the first time I ever used the 14mm Denkmeier. John Huntsberger one of our regular Texan visitors to Coonabarabran was observing open clusters with me in my 10"/F5 newt at Coonabarabran about 7 years ago. I had the 14mm Pentax XW in the focuser as we toured through open clusters in Carina, Vela, Crux and Centaurus. I thought the 14mm XW was giving very nice views. John asked if we could substitute one of "his" eyepieces he had brought over with him. As is the correct protocol with the visitors, I of course said "sure". Muttering to myself under my breath I thought, "probably a piece of Chinese cr_p". John went inside and bought out this black funny looking thing, which on appearance only reinforced my suspicions of its far east origins. It was dark and I didnt get a good look at it as I stuck it in the focuser by "feel". How wrong I was. It took me all of about 2 seconds to realise the eyepiece wasn't a far east clone of anything. I spent about a minute sucking in the view and was "gobsmacked". The only words that could come out of my mouth were "Hol_ Sh_t". Subsequent discussions with John H revealed the origins of the eyepiece as a US made Denkmeier 14mm; and not a budget eyepiece in any way shape or form. I was forever impressed. The improvement it showed over the non paracorred Pentax 14mm was very significant. It has all the positive on axis attributes of the 14mm Pentax including comfort, sharpness, contrast and cool colour tone, but the EOF performance is noticeably improved. The Denk is tack sharp right to the very EOF at F5.
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Originally Posted by Suzy
Andrew: Thankyou for clarifying the eye cups on the Denks. for me.
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These winged eye cups are totally removable if you wish. You can also replace them with a normal "round" rubber eyecup available for about $5 each.