Pentax 7 & 14mm XW - First Light in a Dark Sky Location

[faulksy]

also thinking about it i use the 5mm most nights that im out on clusters and it is awsome, hence the 3.5 or 3.7 ethos

[John]

also thinking about it i use the 5mm most nights that im out on clusters and it is awsome, hence the 3.5 or 3.7 ethos

I've often compared the views through my 6mm Ethos and my 5mm XW becuase they are frequently interchanged as I try and determine which magnification is giving me the best views on a particular object under particular conditions.

Optically they are very much more similar than different. It's the AFoV, the eye relief and the price that differentiates them. I doubt the 3.7 or 4.7 Ethoi would actually outperform the XW equivilents in any way although the views could be more "impressive" due to the massive FoV 

[faulksy]

I've often compared the views through my 6mm Ethos and my 5mm XW becuase they are frequently interchanged as I try and determine which magnification is giving me the best views on a particular object under particular conditions.

Optically they are very much more similar than different. It's the AFoV, the eye relief and the price that differentiates them. I doubt the 3.7 or 4.7 Ethoi would actually outperform the XW equivilents in any way although the views could be more "impressive" due to the massive FoV 

hi john, like you say you would be able to beat the 3.5xw, the only reason i wanted the ethos was for the bigger fov so less nudging and easyer to find if you do loose it

[John]

hi john, like you say you would be able to beat the 3.5xw, the only reason i wanted the ethos was for the bigger fov so less nudging and easyer to find if you do loose it

Yes, those are decent reasons. The change from the XW's to the Ethos SX's would cost me £500+ taking into account proceeds from selling my XW's though

[alan potts]

I feel it is all about FOV, I have and have had almost all of the short focal length TVs and have used all short and own 1 Pentax XW. If we are talking purely on axis and the area around about I really don't think there is anything to choose between any of them.

Some say Pentax are more neutral than all TV"s offerings, some say Radians and Naglers have a yellowish caste to varing degrees, there may well be slight scatter differences but when it comes down to it all are sharper than  Ken Dodd and Bob Monkhouse on axis and it is only the amount of extra field that varies. In my opinion all I have looked at are pretty dam sharp out there too.

Ethos will rightly always appeal to the Dob owner and as said less scope movement, they are a breath of fresh air with my poor nudge skills, I could loose the Moon in the scope with one. Whereas for planetary they are a luxury, especailly if the scope is driven.

I am not skilled enough to go to X400 plus but I must give it a try as I keep reading of cluster observations at 300 plus. At least I a 5mm Nagler to give some room for error over my Pentax XW 5mm, I also have the Hutech 5mm but that will be hard work for anyone.

[faulksy]

Yes, those are decent reasons. The change from the XW's to the Ethos SX's would cost me £500+ taking into account proceeds from selling my XW's though

that should of said wouldnt be able to beat the 3.5 xw. thats why i havnt got one yet john, tempted with a pm though

I feel it is all about FOV, I have and have had almost all of the short focal length TVs and have used all short and own 1 Pentax XW. If we are talking purely on axis and the area around about I really don't think there is anything to choose between any of them.

Some say Pentax are more neutral than all TV"s offerings, some say Radians and Naglers have a yellowish caste to varing degrees, there may well be slight scatter differences but when it comes down to it all are sharper than  Ken Dodd and Bob Monkhouse on axis and it is only the amount of extra field that varies. In my opinion all I have looked at are pretty dam sharp out there too.

Ethos will rightly always appeal to the Dob owner and as said less scope movement, they are a breath of fresh air with my poor nudge skills, I could loose the Moon in the scope with one. Whereas for planetary they are a luxury, especailly if the scope is driven.

I am not skilled enough to go to X400 plus but I must give it a try as I keep reading of cluster observations at 300 plus. At least I a 5mm Nagler to give some room for error over my Pentax XW 5mm, I also have the Hutech 5mm but that will be hard work for anyone.

try some polish alan on your ground board bearings, makes high power observing lots better. i tried my 5mm bgo great views but hard to keep in the fov, once its gone its gone

[alan potts]

Mike,

I don't know what it is but mine slides on the two white pads either side. All I have is something like Pledge or car polish, did you mean that?

Sorry for being off topic Shaun.

Alan.

[Pig]

Please carry on guys its very interesting..... the only question you all need to answer is which one of you is going to sell me their 5mm

[faulksy]

Mike,

I don't know what it is but mine slides on the two white pads either side. All I have is something like Pledge or car polish, did you mean that?

Sorry for being off topic Shaun.

Alan.

yes alan just the job. do the bearing surface not the white teflon pad , does make a big difference

[alan potts]

Mike I will apply the Pledge Pronto, which believe it or not is what it is called here.

Shaun,

Give me a while to go through the motions of playing the 5mm Nagler against the XW and I will see which I will keep, I need something to write about, they are both very nice eyepieces and I do have and will keep the 4.5mm Delos which in honesty gives a better power for the scopes I use it in.

Alan.

[Pig]

Alan,

As long as the price drops by £10 per day... I am cool with waiting

[John]

Alan,

As long as the price drops by £10 per day... I am cool with waiting

You gotta love an optimist

[alan potts]

I am going to write a review and try and keep it below the size of a Stephen King, come to think of it, if I just use bright stars I could call it the The Shinning.

Had the two 5mm's, XW and 5mm Nagler out last night for a good session, can you believe it was still 32 degrees at 11 o clock last night. The seeing was pretty good though had the 3.5mm in the APO at X227 for 5 mins on Saturn and all was fairly solid.

Alan

[Pig]

As long as reviews don't need an index we should be ok   Associating film titles to the review would be a good idea though

I was out until about 9:30 here observing the crescent Moon and I only had my T-shirt on and there was a lovely warm breeze. The seeing was very poor and wobbly at 200 x mag due to the Moon being so low.

[faulksy]

As long as reviews don't need an index we should be ok   Associating film titles to the review would be a good idea though

I was out until about 9:30 here observing the crescent Moon and I only had my T-shirt on and there was a lovely warm breeze. The seeing was very poor and wobbly at 200 x mag due to the Moon being so low.

you had nothing else on just a t shirt

[Pig]

you had nothing else on just a t shirt

And my baby Crockett pants of course Mike it was very warm indeed

[faulksy]

And my baby Crockett pants of course Mike it was very warm indeed

couldnt resist :grin:

[Pig]

£20 cheaper so far.... I might get the 5mm for free at this rate

[F15Rules]

Hi Shaun

Great report on your XWs:-).

Am I right in thinking you sold some XLs a while back? If so, how do you rate the XWs by comparison?

I've read a few reviews on CN that seemed to suggest that the XWs main advantage was a bit wider FOV? (70 deg XW vs 60deg XL I think?)

What do you think? I don't like more than 70deg anyway and am quite happy with 60deg, so given the price difference between the two series on the used market would the XLs satisfy on axis etc?

Would welcome any opinions:-)

Dave

[alan potts]

Dave,

I removed the double post. I thought XL's were 65 degrees FOV?

Alan

[John]

XL's have 65 degree AFoV's I believe Dave apart from the 28mm XL which was 1.25" so limited to 55 degrees.

I believe that there are a number of differences in optical design between the two ranges including glass types used and coatings. The XW transmission is slightly higher than the XL's.

I've only used XW's so can't compare the actual optical performance of the two types but my reading over the years suggests modest improvements with the XW's similar to, say Type 1 vs Type 6 Naglers or Baader GO's vs Circle-T classic orthos maybe ?

The XW's dropped the 28mm in the 1.25" size and moved to a 30mm and 40mm in the 2" fitting.

One thing they do have in common is that I understand they were not designed for astronomy but terrestrial spotting scopes

[Pig]

Hi Shaun

Great report on your XWs:-).

Am I right in thinking you sold some XLs a while back? If so, how do you rate the XWs by comparison?

Would welcome any opinions:-)

Dave

Dave,

Thank you

There has been quite a time gap betwixt me owning the two types, I found the LX's just fine, they gave fantastic views and I would gladly recommend them. The main difference now is that my main scope is an F5 and this requires an eyepiece that can handle it. I have never tried an XL is a scope of this speed.

The XW's have been quite a revelation to me to be honest and I have not found any eyepieces to date that have bested them, one could say and quite aptly so, that they just fell out of the sky. There is certainly a step up in quality with the XW and rightly so as there is a much bigger step in their cost.

Like you I find 70 degrees more than enough.

I hope this helps

[Pig]

I hope to get  5mm XW at quite a knock down price soon  as I agreed with Alan to knock £10 per day off the price whilst he made his mind up to sell it to me  I cant remember if he was as agreeable as I was though.

[Pig]

I have a 5mm on route so I will soon be able to relax   The 20mm turned up on time, but I am just concerned if 3.5 degrees of sky will be enough  I cant find a 30mm anywhere...they seem to be as rare as rocking horse poo.

[John]

The 30mm XW's are out of production now I believe. In the USA they change hands for quite large sums of cash. FLO loaned me a 30mm XW quite a few years back to compare with a Nirvana 28mm and my Nagler 31mm. It was quite a fun "shoot out". No winners or loosers really, just 3 great eyepieces that had their own characteristics

I'm glad you found a 5mm XW. It's my favourite lunar eyepiece in my 12" dob - razor sharp