Replacement for my 5mm BGO

[AlexB67]

Hello dear people 

My BGO orthoscopic 5mm died some time ago,  I am now looking for a replacement for use with my two Dobs in my signature below, I do not need a particularly wide FOV,  something that offers similar levels of contrast and throughput, the nearest multi element eyepieces I have that always come to mind for such qualities are my pentaxes XW/XL, though I am happy with a smaller FOV in this case. 

I have never owned anything by Vixen, for around the GBP 100 mark I can get the 5mm SLV, I tend to use a 5mm a lot in my smaller Dob, the Heritage 130p, but also in the bigger brother occasionally. The 130p does not take heavy eyepieces very well, with that in mind the SLV may well tick all the boxes  ... I suspect. 

Any opinions on the SLVs ? how do they compete with the XWs (except for the smaller FOV) ? what about the edge to edge performance  in faster F ratio scopes such as mine,  F4.7 and F5. 

As nice as the BGO has been, I fancy a change from looking through a tiny hole ? I used it so much, so I would like something a bit more luxurious this time.   Who knows, I may still get another orthoscopic at some point for the company, not sure I can live without one for that manly experience ?

Any other suggestions are welcome, I only just started looking and the 5mm Vixen SLV came to mind.

Thanks in advance.

[John]

When I was testing the SLV's for the forum (not the 5mm though I ought to say) I compared the 6mm SLV quite extensively with the 6mm Baader GO and found that the views were practically indistinguishable between the two. The SLV was quite a lot more comfortable to view through of course.

The fastest scope that I used was my F/5.4 12 inch dobsonian and the only issue that I saw at the field edge with the 6mm SLV was a little pin cushion distortion right at the field stop as mentioned in my report here:

https://stargazerslounge.com/topic/217971-vixen-slv-eyepiece-report-6mm-12mm-and-20mm/

If the 5mm SLV is on par with the 6mm then it should be a worthy replacement for your 5mm BGO and more comfortable to view though too.

 

[AlexB67]

I just literally just found your review and read it , thanks John, great write up.   Sounds promising. With 7 elements I would expect them to behave fairly well edge to edge over that FOV ... I suppose. I think I'll just bite the bullet and give the 5mm a go before I talk myself into another pentax XW 5mm.  ?  

[iPeace]

There's a rather nice 5mm DeLite in the classifieds.

[Louis D]

The 5mm Vixen LV and NLV are also quite nice for the right price if you can find them used.

[jock1958]

Bought my 5mm SLV second hand last year for £50 and to be honest its been my most used high power eyepiece.

I've been really impressed with the eye relief, FOV, sharpness and general ease of use!

A super eyepiece and a keeper as far as I'm concerned.

Sorry I cant comment on the 5mm BGO as I've never owned one.

[AlexB67]

17 hours ago, Louis D said:

The 5mm Vixen LV and NLV are also quite nice for the right price if you can find them used.

Thanks. I'll have a look, mind you, the SLV is cheap enough,  I don't mind. I have a few weeks before I go on holiday to ponder ?

[AlexB67]

19 hours ago, iPeace said:

There's a rather nice 5mm DeLite in the classifieds.

Thanks, I've been eyeing it up, hmmm, perhaps for a bit less 3rd hand even if it is as new. I have bagged pentax XW for less ?

I've been out of the latest developments reading reviews for  a few years, so I don't know about the latest and greatest. 

That aside, a new TV delite is almost as expensive as a pentax XW 5mm at FLO. Given the choice I think I'd pick that new, but never tried a Delite. I do have two radians, 6mm and 8mm, as much as I love them for some objects, the so called Radian warmth and weaker throughput is noticeable, reading around, the delite seems to get positive reviews in that regard, and that issue has been addressed.

In the shorter focal length however, I am a bit of a pentax fanboy from experience, for various reasons, when all things considered, not just views, but comfort, eyecup design etc.  My Delos adjustable eye guard is rather prone to moving around, on one radian I have it is much stiffer. I prefer that, but on the other one it slides more easily.   It isn't a big deal, it doesn't bather me during viewing, but outside of that, knowing the position I prefer, it is easy to forget where it was positioned in the dark once it does move.  I prefer the Pentax design in that regard, it stays put.  

[Piero]

I had a Vixen slv 5mm and to me it was a very nice eyepiece. Only sold because of a quite radical change in my eyepiece set. On axis it was better than the naglers t6 and on par with the Delos I owned.

Side note, it also worked particularly well with the baader VIP Barlow. 

[AlexB67]

The SLV is a strong contender, your are all making a strong case, plus, I like bang per buck views ? I'll let you know when a purchase has been made, but don't let that stop anyone making further suggestions. 

The only a negative I heard on the FLO website is a claim that the FOV is somewhat narrower than 50 degrees, more like 45, but that's not critical for me. The BGO was 40 degrees, and your eye has to be right up against it to see all of it.

[John]

I have 2 Delos (17.3 and 14) and 4 XW's. I like them both a great deal. With the Delos I find that I can lock the sliding section very firmly in place with no movement possible until I loosen the grip mechanism.

I've not used a Delite as yet but the reports on them are very enthusiastic.

 

[Louis D]

1 hour ago, AlexB67 said:

Thanks. I'll have a look, mind you, the SLV is cheap enough,  I don't mind. I have a few weeks before I go on holiday to ponder ?

Perhaps used in the UK, but new here in the states, they go for $170.  I can get a used Pentax XL for that money.  The LV/NLV go for $50 to $70 used here.  I rarely see used SLVs for sale, so I have no idea what price they go for.

1 hour ago, AlexB67 said:

Radian warmth and weaker throughput is noticeable

The original LVs are similar, probably because both lines used rare earth elements.  The weird part is I could never actually identify a star missing at the limit in the LV that was visible in another premium 9mm.  It's just that the entire view seemed dimmer without actually affecting limiting magnitude.

[John]

Of the Radian's that I've owned, the older types (with rubber grips on the lower barrels as well as the upper) seemed to have lower transmission than the later ones (smooth lower barrels). The coatings used on the lenses changed between the two versions which might have something to do with that.

 

[AlexB67]

27 minutes ago, John said:

I have 2 Delos (17.3 and 14) and 4 XW's. I like them both a great deal. With the Delos I find that I can lock the sliding section very firmly in place with no movement possible until I loosen the grip mechanism.

I've not used a Delite as yet but the reports on them are very enthusiastic.

 

I am an idiot, I never realised that it could be locked into place,  I forgot about it over time. In fact, I just took it out and indeed confirmed it can be very solidly locked into place via rotation.  I always had in a semi stiff position and used it like that just sliding into position  ever since and forgot over the years  ?  My  score for that mechanism has now gone up tenfold. It never prevented great views mind. 

If the like button had a double  trophy I would give it to you.

I think the  delites are designed like this too correct ?

[AlexB67]

 

19 minutes ago, John said:

Of the Radian's that I've owned, the older types (with rubber grips on the lower barrels as well as the upper) seemed to have lower transmission than the later ones (smooth lower barrels). The coatings used on the lenses changed between the two versions which might have something to do with that.

 

I had great views of faint planetary nebulae with the 6mm Radian where I thought it might struggle, it is a strange beast in some respects, The edge to edge views are superb as with all TVs. In my experience, which is not nearly as great as yours of course, When I  compared my 8mm radian on m57, even the 8mm BST has a tiny bit more pop, as well as stars. doubles etc.  On jupiter,  it is almost as if there is a subtle filter, for that particular application I really love it, I think it also depends on wavelength, so result vary.  I even did a little review here way back.

In any case, I would not call it neutral, OTOH the 7mm pentax XW in contrast is as if there is nothing in the way ... at all. 

I don't  know what generation optics/coatings mine are. All bought for around £100 , no regrets despite what I said above, great eyepieces that brought me much pleasure. Nothing is perfect ?

[Paul73]

I’ve used the 5mm SLV in the same scope (10" f4.7). It is very comfortable, sharp as you like and won’t break the bank. The eyecup is a bit rattley compared many, but when it comes to optics and comfort, it is a winner.

I had my best ever Jupiter views with this eyepiece.

Paul

[iPeace]

4 hours ago, AlexB67 said:

I think the  delites are designed like this too correct ?

Yes.

[AlexB67]

I had a chat with my telescope. My telescope says you only live once so buy what you want.  I must say I enjoy the 60 degree FOV of my Radian and how it holds up across the field, The delite  is a now stronger contender. I am sure if it is anything like my Delos optically, I suspect it is, it will indeed be a delite ? and I can pay homage to my long standing avatar.

I am also fishing for a second hand 5mm Pentax XW if I can find one. In my heart I know anything TV or Pentax I bought to date so far, I will never sell. I am most proud of my Pentax XL 10.5mm since it  a bit of rarity these days, and a great eyepiece.  I did well to bag it years ago for a decent price, well less than half an XW 10mm new, one day it will be an antique. 

[Louis D]

1 hour ago, AlexB67 said:

I am also fishing for a second hand 5mm Pentax XW if I can find one.

I have the 5.2mm XL and have never felt the need to update to a 5mm XW despite having 3.5mm and 7mm XWs.  The XLs can be had for about $170 used here in the states versus $250 or so for the XWs.  I think the 5.2mm XL is better corrected to the edge (I know, it's 5 degrees narrower) than the 7mm XW.  It is also easier to hold the exit pupil.

[iPeace]

I have grown to love my 3mm and 4mm DeLites, they just seem to show that tiny bit more, and they're so comfortable to use, quite luxurious. The XWs are very nice as well, but don't be surprised if you find you're getting a view just as nice from a DeLite at less weight and bulk.

[F15Rules]

On 10/03/2019 at 19:53, AlexB67 said:

Hello dear people 

My BGO orthoscopic 5mm died some time ago,

Exactly how does a BGO die??

Joking apart, I have owned the Pentax XW 5mm, BGO 5mm (it was very much alive when I sold it!?), and the Delite 5mm.

I loved the XW, and the BGO (the XW was much more comfortable in use). I bought the Delite new, but didn't like it ergonomically or optically and returned it. I know it's popular so maybe I got a duff one - but more likely it's me, I have just never taken to many TV eyepieces except for the Nagler T6 13mm which I really liked. 

I would go for the XW5 based on what you have said, or an XL 5.2mm if you can find one (best of luck with that!). Both are wonderful, comfortable eyepieces IMHO.

Dave

 

[rwilkey]

Hi Alex, another ep to consider is the William Optics SPL 6mm, a cracking ep with good eye relief and with the sharp image you are looking for.  Ergonomically, it is a very pleasant ep to handle and is well balanced.  I highly recommend it.

[AlexB67]

8 hours ago, F15Rules said:

Exactly how does a BGO die??

It had an encounter with an oily puddle (which had some nasty additives I guess) it wasn't the same after that  even with cleaning, RIP  ?.   First accident I had with any eyepiece, hopefully last. 

Robin thanks, another distraction ?.  I think I have made up my mind more or less ... 

F15 rules , it may have been you I bought it from coming to think of it ... small world.

btw I love what they have done with the forum, kudos to those looking after it. I didn't post for many a year but never stopped stargazing. The forum seems a much quieter place now from what I remember.

[mikeDnight]

Before you buy anything, check out  Bill Polini's excellent review on CN regarding the Baader Morpheus!

[F15Rules]

3 hours ago, mikeDnight said:

Before you buy anything, check out  Bill Polini's excellent review on CN regarding the Baader Morpheus!

Hear hear ?.. I have 3 Morphii and really like them very much. I refrained from mentioning them due to the cost, but actually you can get a new Morpheus for about the same price as a used XW?

Dave