9mm which one Morpheus or Delite

[Louis D]

On 30/04/2019 at 15:01, Trikeflyer said:

What do people think about the Pentax 14mm?

Steve 

I have the XW's predecessor, the 14mm XL.  If your eyes are young and can accommodate near/far focus, you might never notice its field curvature.  I know I didn't 20+ years ago when I bought it.  However, once I got presbyopia in my 40s, I suddenly realized the edge doesn't focus with the center.  However, once refocused, the edge is sharp, as in astigmatism and chromatism free.  I then got the 14mm Morpheus to replace it.  I suppose over the same 65 degrees, it is better as far as field flatness and nearly as good sharpness wise (the Pentax has slightly better polish leading to tighter star images for bright stars).  However, the Morpheus has slight field curvature starting around 80% out as well as noticeable astigmatism and chromatism starting around 85% out.  The latter does not clean up when refocused for the edge.  Thus, it's a bit of a mixed bag because of its faults way out there toward the edge.  The 9mm Morpheus suffers from neither field curvature nor these edge issues, making the choice between it and my 10mm Delos quite difficult by comparison.

Personally, I prefer the 12mm ES-92 in the true field of view range of the 14mm Morpheus to side step the 14mm Pentax/Morpheus decision. ?

[Trikeflyer]

7 hours ago, Louis D said:

I have the XW's predecessor, the 14mm XL.  If your eyes are young and can accommodate near/far focus, you might never notice its field curvature.  I know I didn't 20+ years ago when I bought it.  However, once I got presbyopia in my 40s, I suddenly realized the edge doesn't focus with the center.  However, once refocused, the edge is sharp, as in astigmatism and chromatism free.  I then got the 14mm Morpheus to replace it.  I suppose over the same 65 degrees, it is better as far as field flatness and nearly as good sharpness wise (the Pentax has slightly better polish leading to tighter star images for bright stars).  However, the Morpheus has slight field curvature starting around 80% out as well as noticeable astigmatism and chromatism starting around 85% out.  The latter does not clean up when refocused for the edge.  Thus, it's a bit of a mixed bag because of its faults way out there toward the edge.  The 9mm Morpheus suffers from neither field curvature nor these edge issues, making the choice between it and my 10mm Delos quite difficult by comparison.

Personally, I prefer the 12mm ES-92 in the true field of view range of the 14mm Morpheus to side step the 14mm Pentax/Morpheus decision. ?

Thanks for the detailed review. I will use my es82 24mm with 2x Barlow to get me in the range for now. 

Steve 

[michael.h.f.wilkinson]

I have the XW10, along with the 7 and 5mm versions, and an 8mm Delos with parfocalizer ring to match it with the others in my planetary line up. I am sometimes tempted to get a 9mm to fill the (perceived ) gap between the XW10 and Delos 8mm. The Delite 9mm was certainly a candidate, but I might consider the Morpheus 9mm as well. I didn't get on that well with the Morpheus 14mm, for the reasons listed by Louis above, and replaced it by a Delos 14mm. I have gathered the Morpheus 9mm is better than the 14mm (from Louis and others) so should probably give it a spin. I think it is parfocal with the XWs which is an added bonus.