All in the Coatings?

[andrew63]

Hi All

Came across this good article which some of you may have seen.

I'm thinking the second eyepiece along is a Pentax - as to what the others might be you can fill in the gaps - we don't want to court controversy on a quiet Sunday afternoon!

Coating/Obstruction Comparisons

andrew

[John]

That settles it - I'm going to have to buy a set of Zeiss ortho's !.

Pity they go for around £400 each, used and are as rare as hens teeth

Roland writes some interesting articles though - he certainly knows his stuff.

On eyepiece light transmission, this thread on Cloudynights is interesting as are the links it has in it:

Telescope Reviews: Eyepiece Light Trasmission tables

(pity the OP could not spell Transmission !)

[Adrian]

So is that the reason that Televue eyepieces have a reputation for warm colours (never looked through one myself so it is just heresay )

[Damo636]

That Zeiss sure is inky back inside. Its a pity he didn't identify the others although the 2nd from left looks very like a Pentax XW

[John]

So is that the reason that Televue eyepieces have a reputation for warm colours (never looked through one myself so it is just heresay )

The Ethos range certainly don't

The Pentax XW's I've used have also been very neutral in tone though - very Ethos-like in fact.

While coatings are important, other factors such as glass types used, light baffling, internal blackening and quality of lens figuring and polish all contribute to eyepiece performance. If one is messed up it does have a noticeable effect, eg: the first runs of the Burgess / TMB Planetary eyepieces which had an off axis glare issue caused by a poorly machined lens retaining ring.