Ethos + power mate?

[Rob_UK_SE]

2 hours ago, Dantooine said:

190X was very good and I’m happy to top out at that magnificent to be honest. I also tried an es5.5 at 207x, this worked well too.
The 4.7e gives 151x so I have a selection of close planetary options there for good nights. To be honest I preferred the 8e + barlow at 142x last night More so than the 4.7 on its own. Almost to the point that makes me think it may become a little redundant believe it or not.
The nicest thing is the ease of picking up targets manually with 100 degrees at these higher magnifications.
i tried the eye cups up and down on the 4.7 and coped well with both. I have eyepiece extenders on the 6 & 8 and this was good for me too.
To be honest the eye relief difference in distance was hardly noticeable which surprised me a lot. It may account for 1mm but I was quite excited and didn’t really consider it at the time, next time I will concentrate on this but last night the views took over my thinking. 

4 hours ago, John said:

...
I might have to think about getting one of the new designs

 

It’s interesting to hear that you preferred the 8E + barlow last night, although I appreciate that this may well change on different nights and / or targets. Given that the original intention of the Ethos range (or at least in the marketing) was to create two ‘trios’ comprised of the 21/13/8 and 17/10/6 which both utilise a focal length spacing of 1.6, a 1.6x barlow rather perfectly augments the 8E and 6E to almost match the Ethos SX, but without the 110 degree FOV. This is certainly very appealing to me. 😀 Your feedback about the eye relief and being able to achieve focus is very positive news.

As you mentioned, John, this thread has me pondering as well about the newer version.

[RickEm]

4 hours ago, John said:

I'm pleased that you like the Antares barlow and that it obviously reaches focus find with your scopes and eyepieces

The last one that I tried had a slightly different design from the one that you have bought and I think that was the reason for my focus woes. It's good that Antares have re-packaged what is a fine barlow optic so that it can be used in a wider range of scopes.

I might have to think about getting one of the new designs

This is the design that I last used:

The above seemed to use far too much inwards focuser movement. Obviously the new body design that you have has addressed that

 

That’s the version I have, John.  It works fine with my refractor.

[Dantooine]

14 minutes ago, Rob_UK_SE said:

It’s interesting to hear that you preferred the 8E + barlow last night, although I appreciate that this may well change on different nights and / or targets. Given that the original intention of the Ethos range (or at least in the marketing) was to create two ‘trios’ comprised of the 21/13/8 and 17/10/6 which both utilise a focal length spacing of 1.6, a 1.6x barlow rather perfectly augments the 8E and 6E to almost match the Ethos SX, but without the 110 degree FOV. This is certainly very appealing to me. 😀 Your feedback about the eye relief and being able to achieve focus is very positive news.

As you mentioned, John, this thread has me pondering as well about the newer version.

Preference between 142x & 151x may well have been Due to the conditions on the night but to be honest, I wouldn’t miss the 151x if 142x is available. Worth thinking about if there’s a debate about spending £600 on a 4.7e. Is there really that much difference between 100 & 110 degrees ??
 

To some there may well be, but to me 100 is a good and I’m trying to think when the extra 10 degrees would be a massive bonus at those magnifications. After all it’s £500+ for those extra 10 degrees. 
 

seems to me you can have the 4.7 & 3.7 without actually having to buy them 😉

[John]

2 hours ago, RickEm said:

That’s the version I have, John.  It works fine with my refractor.

I would only be using it with my 12 inch dob and that was the scope where the version of the barlow that I've pictured had focus issues.

I've owned the 4.7mm and 3.7mm Ethos SX eyepieces and they are very good and also very expensive. After about 6 months though I concluded that my 5mm and 3.5mm Pentax XW's were slightly sharper and showed a touch less light scatter so I, rather reluctantly, let the 4.7 and 3.7 go to new homes.

For £80, if the new design Antares 1.6x will reach focus OK with my dob, it would avoid having two eyepiece cases open when I want to use 300x and more with the dob.

 

[Dantooine]

54 minutes ago, John said:

I would only be using it with my 12 inch dob and that was the scope where the version of the barlow that I've pictured had focus issues.

I've owned the 4.7mm and 3.7mm Ethos SX eyepieces and they are very good and also very expensive. After about 6 months though I concluded that my 5mm and 3.5mm Pentax XW's were slightly sharper and showed a touch less light scatter so I, rather reluctantly, let the 4.7 and 3.7 go to new homes.

For £80, if the new design Antares 1.6x will reach focus OK with my dob, it would avoid having two eyepiece cases open when I want to use 300x and more with the dob.

 

Where do you think the problem was with the design, the actual locking ring dimensions?

[Stardaze]

7 minutes ago, Dantooine said:

Where do you think the problem was with the design, the actual locking ring dimensions?

Where did buy yours from, I can’t see any UK vendors? I keep toying with updating my cheap Barlow. I’ve been trying not to utilise one but did the other night and felt mines a weakness in the chain.

[Dantooine]

3 minutes ago, Stardaze said:

Where did buy yours from, I can’t see any UK vendors? I keep toying with updating my cheap Barlow. I’ve been trying not to utilise one but did the other night and felt mines a weakness in the chain.

I managed to find one in stock at Rother valley optics. Email them first to check it’s in stock. 

[John]

6 minutes ago, Dantooine said:

Where do you think the problem was with the design, the actual locking ring dimensions?

I think a number of things changed. I reported on them back in 2014 after finding problems with the Mk II design. I'd owned the Mk I and that worked fine. Hopefully the Mk III (that you have) addresses the issues with the Mk II:

https://stargazerslounge.com/topic/229535-would-an-ethos-21mm-and-x16-barlow-replace-a-n31-e13/?do=findComment&comment=2476427

I bought my Mk II from RVO (they were the only source back then as well). They took it back and gave me a refund when I said that I could not bring it to focus in my scope.

 

 

[John]

I've come across this photo from 2011. I was comparing the 8mm Ethos + Antares 1.6x Mk 1 barlow with a TMB Supermono 5mm and University Optics 5mm HD Abbe Ortho. I seem to recall that the TMB Supermono won in outright performance terms but not by that much !.

[Rob_UK_SE]

43 minutes ago, John said:

I've come across this photo from 2011. I was comparing the 8mm Ethos + Antares 1.6x Mk 1 barlow with a TMB Supermono 5mm and University Optics 5mm HD Abbe Ortho. I seem to recall that the TMB Supermono won in outright performance terms but not by that much !.

Thanks for sharing this, John. The height is a little more manageable than the Powermate I feel. I really enjoyed the views through a Powermate (when I had one), but found it too heavy and tall for me at the time.

...very curious to try out an Antares mkII version.

Edited September 6, 2020 by Rob_UK_SE

[Dantooine]

This is the new one for anyone interested. See how the locking ring is machined nicely for grip. It’s very smooth in operation. 

[John]

Looks very nice

Have you had a chance to work out how much inwards focuser movement is needed when using it ?

 

[Dantooine]

1 hour ago, John said:

Looks very nice

Have you had a chance to work out how much inwards focuser movement is needed when using it ?

 

Not actual measurements yet. I think I still had an inch I could have  wound in on the eyepiece that was the furthest forward. Sorry not very accurate or scientific. All the time I could focus so wasn’t concerned. I will have to look at the scale on the focuser and note for all the focal lengths. 

[Dantooine]

1 hour ago, John said:

Looks very nice

Have you had a chance to work out how much inwards focuser movement is needed when using it ?

 

What’s the best way of doing it as I’ve never needed to before? Use the eyepiece without it and then put in and take the measurements needed to focus from that point?

[John]

10 minutes ago, Dantooine said:

What’s the best way of doing it as I’ve never needed to before? Use the eyepiece without it and then put in and take the measurements needed to focus from that point?

That's pretty much it.

A rough idea of the distance that the drawtube of the focuser needs to move when the barlow is used would be useful when you get a chance.

 

[Don Pensack]

The 8mm Ethos has its focal plane so low in the eyepiece that it needs a HUGE amount of out focus when used as a 2" eyepiece (about 0.7" from the focal plane of the scope).

It's better to use it as a 1.25" eyepiece, which requires in-focus unless your scope has a lot of out travel left and very little in travel.

However, using the eyepiece as a 2" in the Barlow puts the focal plane of the eyepiece very close to the lens, and the Barlow will get nowhere near 

it's 1.6x rating if the eyepiece is inserted that way.  It will be much closer to its rated 1.6X if the eyepiece is used as a 1.25".

Edited September 6, 2020 by Don Pensack

[John]

35 minutes ago, Don Pensack said:

The 8mm Ethos has its focal plane so low in the eyepiece that it needs a HUGE amount of out focus when used as a 2" eyepiece (about 0.7" from the focal plane of the scope).

It's better to use it as a 1.25" eyepiece, which requires in-focus unless your scope has a lot of out travel left and very little in travel.

However, using the eyepiece as a 2" in the Barlow puts the focal plane of the eyepiece very close to the lens, and the Barlow will get nowhere near 

it's 1.6x rating if the eyepiece is inserted that way.  It will be much closer to its rated 1.6X if the eyepiece is used as a 1.25".

I found that the 6mm and 8mm Ethos came to focus just fine in the Mk I version of the Antares 1.6x barlow inserted using the 2 inch fitting but the Mk 2 design needed a lot more inwards focuser movement which was too much for my 12 inch dob.

If the latest version of the 1.6x barlow keeps inwards travel needs to a reasonable level then I'd like to try one again.

 

 

[Stardaze]

6 hours ago, Don Pensack said:

The 8mm Ethos has its focal plane so low in the eyepiece that it needs a HUGE amount of out focus when used as a 2" eyepiece (about 0.7" from the focal plane of the scope).

It's better to use it as a 1.25" eyepiece, which requires in-focus unless your scope has a lot of out travel left and very little in travel.

However, using the eyepiece as a 2" in the Barlow puts the focal plane of the eyepiece very close to the lens, and the Barlow will get nowhere near 

it's 1.6x rating if the eyepiece is inserted that way.  It will be much closer to its rated 1.6X if the eyepiece is used as a 1.25".

My 8mm tops out the focuser by a few mm. I’ve ordered an extension barrel and parfocal rings but have been using it all week as a 1.25”. Probably shouldn’t have bothered buying the bits so that it will work as a 2” but when dropping down from the APM 13, I thought I’d keep it all the same.

[Dantooine]

6 hours ago, John said:

found that the 6mm and 8mm Ethos came to focus just fine in the Mk I version of the Antares 1.6x barlow inserted using the 2 inch fitting but the Mk 2 design needed a lot more inwards focuser movement

Just a point John, did you fit the fine tuning rings to the ethos for your 2” filters between the two versions of the Antares ?

[John]

3 hours ago, Dantooine said:

Just a point John, did you fit the fine tuning rings to the ethos for your 2” filters between the two versions of the Antares ?

Good point but I'm pretty sure that I did tke them off when trying to reach focus with the Mk II 1.6x barlow. I really wanted to get it to work because it is a much lower cost alternative to the Powermate 2 inch 2x and gives slightly more useful focal lengths.

No matter, that was sometime ago. I'm glad the current one works well and I might pick up one at some point. It's not as if I'm lacking in high power options for my 12 inch dob with the XW 5mm and 3.5mm and the Nagler 2-4mm zoom. Using 795x on Mars last night when trying spot Phobos was interesting

 

 

[Stardaze]

I'm going to be in trouble later.... was thinking of ordering an Antares 1.6 to give me a 5mm option with the 8mm Ethos. Happened to see that Astronomy 365 still had some Pentax XW's in clearance, so bagged the 5mm. 🤣 That's me done this side of xmas... 

[Dantooine]

16 minutes ago, Stardaze said:

I'm going to be in trouble later.... was thinking of ordering an Antares 1.6 to give me a 5mm option with the 8mm Ethos. Happened to see that Astronomy 365 still had some Pentax XW's in clearance, so bagged the 5mm. 🤣 That's me done this side of xmas... 

Just as bad as me. I bought a tv eyepiece every week for 11 weeks during lockdown just to see which ones I wanted to keep 🤪

here is something to make you realise you have done the right thing:-

[Stardaze]

33 minutes ago, Dantooine said:

Just as bad as me. I bought a tv eyepiece every week for 11 weeks during lockdown just to see which ones I wanted to keep 🤪

here is something to make you realise you have done the right thing:-

Wow! 11 EP's in as many weeks. And top-end ones at that! 😆

I'm trying to buy keepers and think I'm on the right track. I thought that an XW 5mm, and eventually 3.5 too, will be my planetary EP's. I was a bit lacking with Mars the other night and felt my cheapo Barlow was compromising the 8mm ethos. Mars is only going to be this good again in a few years time, right? So, why not make sure I'm in with a fighting chance this time around. Well.... that's my excuse. I'm not certain she will see it that way though 😂

 

PS. £210 is a steal huh! 

Edited September 7, 2020 by Stardaze

[Dantooine]

15 hours ago, Don Pensack said:

It's better to use it as a 1.25" eyepiece, which requires in-focus unless your scope has a lot of out travel left and very little in travel.

However, using the eyepiece as a 2" in the Barlow puts the focal plane of the eyepiece very close to the lens, and the Barlow will get nowhere near 

it's 1.6x rating if the eyepiece is inserted that way.  It will be much closer to its rated 1.6X if the eyepiece is used as a 1.25".

Don,

thank you for the information. So what you are saying is to get a true 1.6x from the barlow, the ethos would need to be used with the 1.25” Part of the dual barrel and that by using the 2” part I was actually getting a much lower magnification than I thought I was getting?

would this also explain a minimal noticeable change in eye relief On the 6 & 8E?

If this is the case I will need to spend an evening trying them in 1.25” mode. 
 

Forgive my ignorance on this as I never thought I would use a barlow and it’s the first time I’ve used one. 
Dale. 

[Dantooine]

10 minutes ago, Stardaze said:

Wow! 11 EP's in as many weeks. And top-end ones at that! 😆

I'm trying to buy keepers and think I'm on the right track. I thought that an XW 5mm, and eventually 3.5 too, will be my planetary EP's. I was a bit lacking with Mars the other night and felt my cheapo Barlow was compromising the 8mm ethos. Mars is only going to be this good again in a few years time, right? So, why not make sure I'm in with a fighting chance this time around. Well.... that's my excuse. I'm not certain she will see it that way though 😂

 

PS. £210 is a steal huh! 

Yes it’s a very good price. Justified. Also, you are correct about mars, 2033 or something next it’s this close. 
 

The main thing to remember is, you would never get to see a crisp view of the Martian dust storms with the 8E and a sub standard Barlow 🤣

ps.. I’m back down to 6 eyepieces now 👍

Edited September 7, 2020 by Dantooine