[Profiler (Profiler)]

Hello John

At the outset - thank you so much for your input - it is very much appreciated.

I have looked at the Pentax XW's which typically feature a 7 or 8 lens design (exception being the 20mm) versus the XF's which both feature a 6 lens design.

I am trying to decide whether it is worthwhile buying XF eyepieces or simply focusing on collecting a set of XWs.

Putting aside FOV and the magnifaction differences between the two series do the XF's optically (in terms of clarity/contrast in what may be seen etc) exhibit any superiority in performance over the XW's?

Is it fair to view the XF's as a physically smaller scaled down version of the XW's with comparatively smaller FOV or are they also slightly inferior (a poor-mans XW so-to-speak) in terms of their optics as well in comparison to the XW's?

One thing I can't seem to establish is whether the XF's do, in fact, incorporate lanthanum glass elements. On some websites the XF's are described as incorporating lanthanum whereas other sites are silent on this point. This is in contrast to descriptions about the XW's which are all clearly described as using lanthanum lens elements.

Thank you in advance for your time and advice.