Antares 1.6x 2 inch barlow

[AlexB67]

Hello, I get the impression the Antares 1.6x  is quite a nice bit of kit, and seeing no standalone  exist 1.5x in an 1.25 inch fitting unless you break the bank, and the 1.5x adapter I use now on occasion on my cheap barlow, while it does the job, in particular in the wider angle eyepieces I can see it degrades image quality a bit off axis too for my liking, not the best contrast and scatter control, though considering what it is I had some good views with in the BGO 5mm to give that 1.5x magnifier, and the Radian 6mm also in both of my scopes. 

Last night Mars was rather excellent and while a tad on the higher mag side  I found myself turning the Radian 6mm into a 4mm effectively by using the 1.5x adapter to give 300x and  used it on the BGO to around 360x on the moon.  Probably quite rare I would use 360x on the whole, except the moon on good nights perhaps, tough it did not stop me even looking at Mars for a bit even at that mag ( one has to try these things ).

Anyway , my thoughts, I don't think I would buy a 4mm just alone, but it got me thinking a bit, as you do when having had a good session the night before

I have a pentax XW 7mm incoming the end  of this week, so that will give me 5,6,7mm line up. With a 1.6x barlow to give me a nice range of mags without breaking the bank  ( The nagler zoom has been in the back of my mind, but not now ).  I feel with the short time we have for Mars  before it goes off, and we wait for another couple of years for another opposition this could be a nice sort of budget fix for now.  I believe the antares barlow moves along quite easily second hand anyway if I want to get rid of it at a later date.  No too concerned by the weight either, it is quite light, though may need to counter weight if need be. even a pentax with the Antares combined is lighter than a lot of single 2 inch eyepieces.

Any comment on using the 2 inch barlow ?, I assume all I need it the self centering adapter in the Antares to use my 1.25 inch eyepieces. I don't think focus travel will be a problem with any of them, but will have to do a few checks to see on the three eyepieces. 

Any other suggestions welcome.

Thank you

[AlexB67]

By the way here is the link the product I am talking about.

http://www.rothervalleyoptics.co.uk/antares-2-16x-barlow-lens-with-twist-lock.html

I know I would not be able to us it in the heritage 130p, it would be for the 10 inch scope.

[andrew63]

Have you considered a baader classic  ?  Can give 1.3 x and might be a more practical solution for a 1.25 barlow.

Baader Classic Q 2.25x Barlow - First Light Optics

andrew

[AlexB67]

I had not,  thanks for the link and will look into it, My slight reservation about the adapter type barlows that they are not really optimised when pushed that close to the eyepiece and work better in full mode, perhaps I am being overly picky,  but my feeling is that the dedicated 1.6x barlow is a better option in that sense, but would be interesting on views on that thought.  If I buy the Baade classic, no doubt it is somewhat better than my current barlow mind you     

[John]

I've had a couple of the Antares 1.6x 2" barlows over the years. The first one used set screws and did not have a 2" filter thread at the bottom of the barrel. It was great optically though and worked particularly well with my Ethos eyepieces. 

I had one of the more recent ones with the twist lock eyepiece holder and threaded for 2" filters. Optically it looked just the same but in implementing the twist lock facility and the filter threading they somehow moved the optical elements within the tube and the effect was that somewhat more inward focuser travel was required to get any eyepieces to focus. Too much for most of my eyepieces in my 2 refractors unfortunately so I had to part with it

[AlexB67]

I've had a couple of the Antares 1.6x 2" barlows over the years. The first one used set screws and did not have a 2" filter thread at the bottom of the barrel. It was great optically though and worked particularly well with my Ethos eyepieces. 

I had one of the more recent ones with the twist lock eyepiece holder and threaded for 2" filters. Optically it looked just the same but in implementing the twist lock facility and the filter threading they somehow moved the optical elements within the tube and the effect was that somewhat more inward focuser travel was required to get any eyepieces to focus. Too much for most of my eyepieces in my 2 refractors unfortunately so I had to part with it

Thanks for that John, Darn, a major spanner in the works ? so much for my plan I better start checking some of my eyepieces and focuser travel requirements and various bits to see if it will work in my case more carefully.  Just as well you mentioned that,  or perhaps I'll be lucky and find an older second hand one with the setscrews, but whenever you look for the things at the time you want them they don't turn up of course

[alan potts]

Alex,

It was on the back of Johns second Antares Barlow that I didn't get one when one was up for grabs. Both the scopes that I was going to use it on were of limited inwards travel and bear in mind he had had a problem on both his refractors. If on the other hand it had been for my LX or Mak it would not have mattered as they seem to focus absolutely anything. Last night I was doing a little test for Yong by removing the diagonal and viewing Sirius, no sweat, diagonal off, twist twist twist and there it was sharp as , well as Sirius can be.

Alan

[AlexB67]

Thanks Alan. I'll have some more reading to do tonight, I think in the Dob with my setup I think it will be okay for the focus travel ( I think ). If I did it is sort of just in the price I'll grab one new for just under 80 pounds, Rothervalley are quite helpful I believe who can help me no doubt on that, the only place I think that sell them but will see what they say as well.

I will have broken my rule of buying a second eyepiece in one month mind you if I do, but hey, no doubt Ronin will be in my case saying I wouldn't last buying one eyepiece per month . I owe him one, but Mars will not be around for long to make the most of it is my excuse,  also a barlow is not an eyepiece   . 

[John]

Thanks Alan. I'll have some more reading to do tonight, I think in the Dob with my setup I think it will be okay for the focus travel ( I think ). If I did it is sort of just in the price I'll grab one new for just under 80 pounds, Rothervalley are quite helpful I believe who can help me no doubt on that, the only place I think that sell them but will see what they say as well....

I bought my 2nd one from RVO. When I explained the issue about the additional inward focuser travel they agreed to give me a refund less the postage costs, which I thought fair as the product was not faulty as such.

[Pig]

Alex,

I tried to get one from RVO but after 7 weeks of waiting it still did not materialise, I cancelled the order in the end.

[AlexB67]

Alex,

I tried to get one from RVO but after 7 weeks of waiting it still did not materialise, I cancelled the order in the end.

Cheers for that Shaun. I'd be on the phone beforehand or by mail anyway to make sure what the situation is, never trusted those "in stock" statements on websites anyway, though the better sites/sellers are decent with that and the site at Rother valley says as much to check beforehand

[knobby]

Same as Shaun here... Let us know how you get on

[Pig]

They were very honest Alex, it just didn't show from the USA after to deliveries

[AlexB67]

Still not decided on this one , it was brought to my attention the Baader VIP modular barlow is very good, but it is a lot more costly.  I have tested my own 2x barlow in the pentaxes and Radian, and since they already have 20mm eye relief I find when I use the 2x barlow  it is too much, it becomes annoying with the extended eye relief, so I would not want to use 2x much since I do have to back off enough from the eyepiece, and you cannot even see all of the field stop having to screw in the eyecup to compensate, so it really begins to feel too far back for my liking.

With the current very cheap 2x barlow and 1.5x adarpter I have I find it is okay in 1.5x mode, so the 1.6x Antares is still my preferred option in a way, especially after reading a report the XWs fairing well in it, it would mainly be for the 5mm BGO, 6mm Radian ( 200x)  and 7mm XW ( 171x), with the 1.6x multiplier this would give me approximately 384x 320x, 273x, good for Moon, Mars the times I can push that mag that high.  I've been testing these mags with my current setup with the 1.5x adapter quite a bit, the 1.5x actually works quite well  in the BGO, but less good in the Radian and pentaxes is my impression.

Time to ponder. I may well let it go this mars season and stick with what I have for the time being, think about it at a later time, rather than a rush buy a solution now such a the VIP which no doubt while very good, but is getting on costly. The antares is still at a sort of price level I can  happily risk it and see a bit more.  The antares also has a nice conversion of my 28mm MV to a 17.5 mm, same mag as the Delos 17.5 I would like to get, so a handy sort of tester for that.   

Twist my arms for something else

[jetstream]

Well there is another solution(s) to high power viewing,besides the barlow.We could always get a longer focal length scope or try a 3-6 Nagler zoom.I have the zoom and like it,but it is not quite as sharp as the Delos on some things,some times.At times though its warm cast and variable mag work very well-better than my cool orthos once in a while.The best view of Mars came with the 3-6 Nagler,costly though.I am also playing with non tradition aperture masks,for a circular equivalent 4.7" ap or so...and its working.If I bought a barlow as a permanent solution to high power viewing I would get the Baader,if not sure I would spend less

[AlexB67]

Gerry, I agree, the naglar zoom would be a worthy investment in the long run as mentioned in my first post, I suspect I'll end up with one of those eventually  .

I was more looking for a sort of stop gap solution, nothing too expensive, but something that at the same time will provide enough of a worthy optical improvement over my current cheap 1.5x adapter I have found myself using quite a bit recently, and my feeling is the Antares is good enough for that, my barlow that came with the scope must be a 10 - 15 pounds barlow I suspect, no more, it came with the heritage 130p.

I am actually surprised how well it has actually served me, but it does add quite a bit of scatter, affects FOV performance in the wider angle eyepieces such as the pentax and radian and sharpness.  When I compare similar or close mags with the 1.5x/2x  and eyepiece compared to just and a single eyepiece , the single eyepiece does come out tops. 

I can compare   7 XW + 1.5 barlow, 10.5 XL + 2x barlow, 5mm BGO, in terms of performance they pretty much come out in that order of being sharpest and FOV performance, best contrast in the BGO.  I also tried other combos also. The barlow actually works a tad better in 2x mode I feel, which does not entirely surprise me, since often pushing a 1.5x adapter that close to the eyepiece can be less optimal, or so I am led to believe this can have adverse affects in terms of optical correction, when they are optimised more to be further away from the eyepiece to begin with.  A better design triplet barlow would be more forgiving for that I suspect when specifically optimised to work as a shorty.

In any case the are exceptions to every rule I guess, the proof of the pudding will be in the eating if I decide to get one

[jetstream]

Alex see if you can try a zoom first before buying.Mine kind of bugs me....its great for some things,but there are better EP's optically out there.But then I'll need high power in the dob and the adjustability works so well to fine tune things,so handy.Having to switch up EP's all the time can be a pain,losing valuable seeing time.Not sure what the answer is for me yet now that the seeing has improved.

[John]

Another low cost barlow that performs very well is the Baader Q-Turret 2.25x. It's a no frills design and it is 1.25" format of course but optically it did seem to "get out of the way" apart from the boosted magnification.

[AlexB67]

The price tag looks attractive for a stopgap solution that may not be such a bad idea after all, it was suggested earlier in the thread as well as on option.

Do you happen to know if this is a 3 or 2 lens design ?  Have you tried it  with wider FOV eyepieces and used the 1.3 mode adapter in its own in that way ? My reservation is that such a barlow wil be okay with narrow FOV, and quite good on axis, but that it will suffer in wider FOV eyepieces, more so with the 1.3x multiplier in particular when screwed directly onto the eyepiece.

My other reservations but there are some measurement on it I found, it does look rather short. If I use the full 2.25x I wonder if it does have enough length to house some of my eyepieces, but I can check that. I do wonder the shortness  for the eyepiece fitting is down to the fact it was designed with the orthos and Q turret in mind where that would not be an issue.

Still for 50 pounds even if it brings an improvement it would do for the time being over my current one, and I quite like the soft 1.3 muitplier idea, mostly what I would use, it brings some interesting options.

[John]

I ought to mention straightaway that the 1.3x mode, where the barlow lens element is screwed into the filter threads of the eyepiece, will only work on designs that don't have a lens group in the barrel of the eyepiece. The barlow lens element needs a fair amount of clearance up inside the 1.25" barrel to fit. It's fine with orthos and plossls but not most wide angle designs. 

I could not work out how many lens elements the Q-Turret barlow had but I fancy that it could be a 3 element system from the thickness of the lens set.

The barlow lens set has a decent aperture - probably around 25mm or so but I didn't actually measure it. I used it mostly with the Baader Classic eyepieces but I do recall using it with a few of my other ones and it seemed to work well. I can't exactly recall which though. Sorry.

[AlexB67]

Thank you all for the contributions.  I did put an ad in for the Antares, who knows, some poor soul may want to sell me one  .  The more I read about that one the more I am lured towards it as a as sort of good bang for buck solution for the foreseeable future, but will see. If the price is right than I may just grab a second hand, or if I run out of patience pay the full wad for a new one, or leave it altogether. How decisive of me

[AlexB67]

Just to update on this. I did decide to let the idea go of the Antares 1.6x idea. It was in part the driving force for snapping up a 8mm Radian, not that I really needed one as priority, seeing I already go the 7mm pentax, and every time  so far I put the pentax XW In the scope and go back to a 8mm BST, the pentax just gives the better views, and the FOV is almost the same, that eyepiece is just mind-bogglingly good, it's a true performer     So not really finding that much use for a 8mm often, though it is a nice option in these rather closer focal lengths, where one in some cases one may favour the situation for the more pleasing views.

So about the radians, when it comes to planetary I do love the 6mm Radian I currently own, I wanted some more of that Radian rendering in my case, and while the 8mm turned up I was sufficiently enamoured by it, based on the experience of the 6mm, so  I surrendered to its charm and snapped it up.  

The 6mm is probably and arguably my favourite on globs too and jupiter, even if the pentax show fainter stars a bit more on globs,  and on Jupiter and Saturn has shown me some of the best low contrast detail I've ever seen, as well as the ring M57 last week in the Hertiage 130p, It was outstanding to see that lower contrast detail stand out.

BUT

the immersion factor and that slightly more toned down view in the Radian has something I really like, so some of it is just personal taste I am beginning to find, it is nice to have that bit of variation in the case 

As for the Antares, the outcome is that I intend instead to get a 2x focal extender instead of the barlow route,  that for high power works with the 6,7 and 8mm will give me some nice high mags for the moon when I can use it, double stars, and some of the brighter small planetary nebulae when needed also. Witht he pentax XL 10.5 it gives me a 5.25 a wide anger option when the BGO is not in the mood for the night. I found myself using a my cheap 2 x barlow quite a bit, so it is time to get a good  substitute for that at some point in the near future.  Another consideration,  when I do get that paracorr as some point, and whether I would use it for planatary or not remains to be seen,  the 1.15x multiplier will shift things a bit, the 8mm will also be that bit more in the mag range where it will get more use.