Yet another diagonal vs reducer related upgrade - Evo 9.25

[Viktorious 2]

Time for yet another cry for help when it comes to choosing diagonal. I have read the many similar threads and gathered some knowledge (too many to start linking). I have come some way in my process and now that it is coming to final decisions I would like to hear from the experts. Not many of threads I have read end with the OP returning to deliver some review/verdict of his/her final decision. While I wait for response on some thread where I asked about the result, the eagerness in me forces me to write my own thread. Perhaps some of the people asking these questions before can now answer in my thread as experts!

I have the Nexstar Evolution 9.25 and am currently using the stock diagonal. My eyepieces are the Baader 8-24 mm zoom and the stock 40 mm Plössl. I would also like to upgrade EPs and there I'm looking at something better in 24 mm range, as well some nice low power for more FOV. I'm following threads about EPs and SCTs with great interest for this (on CN). Can say that I'm currently leaning towards the 1.25" 24 mm ES 68° and 2" 36 mm Hyperion aspheric (if going 2" route).

I'm thinking 2 alternatives (including a budget alternative for one of them). I'm looking at Baader mainly for ClickLock (and expect good optics):

• Baader T2 Zeiss prism with a 1.25" ClickLock EP (T2 part #08) -OR- the 2" prism with 2" ClickLock (splurging that is).
• The budget alternative would be to get the non-Zeiss T2 prism instead for the 1.25".
• Worth noting that I would like to get the Celestron f/6.3 Reducer/Corrector. This would be for future purposes of delving into EAA but of course I would use it visually as well (especially if choosing the T2 route).

The reasoning for my alternatives:

• Go for the 2" Zeiss prism to theoretically get the best of the best in visual terms. I would make better use of the 46 mm baffle tube opening. Theoretically possible to combine with the R/C thanks to relative short light path (although not necessarily needed with 2" EPs). Downside of going to 2" accessories would be the cost, EPs, filters etc., on top of diagonal. Would not be able to spend all these costs at once.
• Cheaper route with T2 prism (especially the non-Zeiss), not only diagonal but also the other accessories. Cost of the R/C would be comparable to e.g. the 36 mm aspheric and give similar power and FOV with the 24 mm ES, i.e. the 24 mm would act as both. Extra plus is the ClickLock clamp for 1.25" with built in fine focusing not involving the mirror. Downside of knowing that not all light coming out of baffle tube is used. To get the wide FOV (24 mm + R/C) I'm adding glass to the optical train (theoretically not a good thing).

I'm leaning towards the T2 as it would be a cheaper diagonal and for EPs I would only need the 24 mm and then the reducer instead of a 30-40 mm, so saving the expense of one EP. Then I would already have the reducer for continuing into EAA. The questions I hope the experts here can help with:

• The old reducer vs 2" diagonal question. With R/C and the 24 mm I can get roughly the same mag and FOV as e.g. the 36 mm Hyperion (technically 38 mm vs 36 mm and 68° vs 72°). Also reading good things about the ES 68° and with R/C the EP should behave the same. Am I missing something here? The logics say that the I would lose some contrast with the R/C (not using full opening + adding elements), correct? Possibly flatter fields though (not important now, hopefully the EP threads might tell soon enough).
• The Zeiss vs non-Zeiss T2? Big differences? I have read a few posts on this so most to get some updated views here (have read that Baader has changed some things over the years).
• Using the R/C (f/6.3) with these prisms. I know f/7 is mentioned as "the limit" but also remember BillP's test where he was happy down to f/6 with the prisms (in 2014 at least).
• Perhaps most important: have I missed some other obvious alternative here?

Maybe I have forgotten some question here but perhaps for the best as I assume those who have gotten this far are tired of reading now. Thanks for getting here though!

Thanks,
Viktor

[johninderby 4,574]

One note re: the T2 Zeiss. It is out of stock until the end of January.

[JTEC 151]

Viktor, I have both the Baader Zeiss prisms. BillP gives a slight nod to the 1.25 over the 2” but I’ve never found myself swapping the big one out and the small one in in pursuit of improved quality ... both are excellent. I haven’t used the non Zeiss Baader prism so can’t comment on that. Other diagonals I’ve used include the Baader t2 mirror, the AstroPhysics dielectric and a William Optics dielectric. The WO and Baader mirror performed to my eye on a par with the AP, with perhaps surprisingly maybe a slight edge with these examples to the WO, but both the Zeiss Baader prisms, imv, clearly outperform them all in terms of contrast, brightness and freedom from scatter. If you could stretch to the 2” Zeiss Baader, you’d be assured, I think, of unsurpassed quality and be covered for all future eyepiece options etc. There’s no difference that I can see which should push you towards the 1.25 rather than the 2 on performance grounds, so imv the choice would be down to affordability and intended  use. 

Edited October 12, 2019 by JTEC

[Viktorious 2]

John, I've seen that.. Looks like it's on stock at microglobe but haven't dealt with them so don't know how well they update the website. Maybe I shouldn't have said that if they have 1-2 left and now people reading this will buy them before me!

 

JTEC, thanks, your experience shows that I've thought correctly so far. May I ask what scope you're using (f-ratio and such)? As mentioned I wouldn't go for 1.25 for any performance edge, it would purely be for financial purposes.

I can get a complete T2 Zeiss + reducer for ~£50 more than the 2" alone. Then I would have to get a ClickLock VB or locking ring for the 2", so the cost would be roughly the same. Then for EPs it would be enough with the 24mm for the T2+reducer whereas I would also need a 30-40mm for the 2" (£150-200). Other accessories (e.g. filters) would be pricier in 2". The want to try EAA would mean an extra £120-140 for the reducer if I've gone the 2" route. 

So, scaling it down like this basically brings it to: is the 2" 30-40mm view ~£200 better than the R/C 1.25" 20-25mm view? On top of that £200 I would also be ~£130 poorer (the cost of the reducer) when looking at cameras for EAA. 

Edited October 13, 2019 by Viktorious

[JTEC 151]

Viktor, the scopes are TEC140, f7 triplet apo and C11 f10 SCT. I use the prisms mono and also with Baader MkV bino. Actually, I only have one 2” eyepiece now (ES 30mm 82*), so, for most things I’d be entirely happy with the BZ 1.25 prism. The 2” prism gets used, of course with the 2” eyepiece, but also when I put a Televue 2x 2” Powermate ahead of the binoviewer. If I’m not using the Powermate, the 1.25 prism - which has a relatively short light path - works with one of the Baader GPCs  (usually the x 1.7 > 1.5) very well indeed. Both are mechanically robust and the Clicklock fittings I find to be a delight to use.  BW  John E

[Viktorious 2]

Thanks for the help John E.

The T2 Zeiss is ordered. Apart from this thread I also re-read some of the old threads and came to the conclusion that 1.25" EPs with reducer will be good enough for me (I hope ). Still kept reading that differences could be discerned between the Zeiss and non-Zeiss so went the "better" way there. In the end I feel like I'm getting premium equipment and at least I didn't go the most expensive way (still going to have to live on ramen for a while).  

Edited October 14, 2019 by Viktorious

[JTEC 151]

Well, I think it’s fair to say that you’ll never ever need to fork out for an upgrade because the Zeiss prisms are as good as it gets. If there is anything better, I don't know what it is. Before purchasing mine, I took note of BillP’s reviews.  After my own tests, I felt that, as with most things, he was right on; that’s still my view.  Off went the Astrophysics dielectric to astrobuysell. And, as a convenient plus, you get the Clicklock mechanism. ATB John E

 

[John 26,274]

I use the Baader T2 Zeiss prism with my Takahashi FC-100DL and it works very well. I also have a couple of Tele Vue Everbrights and an Astro Physics Maxbright which I also think highly of. The Baader T2 suits the slim lines of the Tak very well but in all honesty I've yet to see any optical difference between it and the Tele Vue and Astro Phiysics mirror diagonals when I've swapped them about on my refractors

I have read BillP's reviews as well, more than once I have to say - they are good reads

 

[JTEC 151]

1 hour ago, John said:

 

I have read BillP's reviews as well, more than once I have to say - they are good reads

 

Agreed.  The weather we have here at the moment is perfect for reading reviews ... 🌧

 

[Viktorious 2]

I can't not comment on the fact that the Johns are very helpful here ! 

Edited October 14, 2019 by Viktorious

[Viktorious 2]

Can update that the package has arrived (last Friday), within the promised 5 days. Checking microglobe now the diagonal is not reported to be in stock, so might be that I have the last T2 Zeiss that was available for now, pretty cool! 

 

On other notes I can recommend microglobe (was my first experience with them). Fast delivery within EU (UK company) and most importantly the lowest price on Baader equipment! I also got the Celestron f/6.3 reducer/corrector there and that price must be the cheapest in the world (£97). So that's a tip for UK/EU residents (EU for 10 more days?). 

 

Now I'm just waiting for my mount so I can use all my new stuff. Had to send the mount back due to some wobbly clutches.. 

 

Clear skies, 

Viktor 

Edited October 21, 2019 by Viktorious

[johninderby 4,574]

Sometimes they do have very low prices on astro equipment, but not always,  but worth checking out.and they do have very good service.They are what you would call box shifters so don’t ask them technical questions.

Bought a pair of Nikon bins off them last year but later on put them on eBay and got what I paid for them.

Edited October 21, 2019 by johninderby

[Louis D 2,447]

I've order some Baader items from Microglobe that were shipped to the US in the past.  There were some initial ordering hiccups with CC payment and removing VAT, but they came through in the end.

The Celestron f/6.3 Reducer Corrector Lens is available for $113 shipped and sales tax free to most states in the US from both Agena Astro and B&H Photo.  It would be a few dollars more shipped to the US from the UK once VAT is removed, especially since the GBP has recovered a bit off of its August lows relative to the USD.