Premium APO to go with a C11

[IanH]

Hi Everyone,

Firstly, I apologise for asking a question which I know is a common one.  

Having had a Celestron C11 for about a year and enjoyed it very much, I would like to add a wider field of view and have something that packs fairly small in the boot of the car, so I'm looking at  a 4" apo. 

I can go up to say £3.5k for a new scope  (if I don't spend it I have to put it into a pension and then it's lost forever!).  I am currently visual only with moderately light polluted skies (Bortle 5 to 6).

I've narrowed it down to the Televue NP101 vs Takahashi TSA102.    

I know these are both awesome scopes with different strengths and large numbers of fans.  But they are a lot of money, so I just want to try and avoid buyers remorse and wishing I had got the other...

My thoughts are that, in theory, I like very much the idea of  the "flat" wide views of the TV NP101, and it comes as a nice package.  What I don't know is whether in practice I would really see much of the legendary starry vistas.

Do you need to go to a truly dark site to get the  benefit of the NP101 view?  As in reality I'm likely to use it 10 times under light pollution for every 1 time under even a darkish sky.

Would I be better off going instead for the  Tak TSA102, with it's  reputedly very sharp contrasty optics, which might perform better under normal home conditions? Is the field curvature of the Tak going to be noticeable?  It has quite a wide view - but not as wide or flat as the NP101.

The other thing, of course, is the Tak is cheaper - I could add a Nagler 31 or an Ethos 21 for the price of the NP101.

One thing I've learned in my short time in this hobby is that it is a lot about compromises.  eg. perhaps adding a decent pair of big binos  to the TSA102 will do the same job as the NP101.

I would appreciate your help and experience, as I have gone around in circles for months reading reviews etc.  and it's time to make up my mind....

Thanks,

Ian

[rowan46]

I can assure should I buy a televue or a takahashi is not a very common question sorry I can't help but I would love to know the answer.

[dweller25]

Tak - but I am biased

[John]

I've not used either but I'm sure both are superb examples of 4" refractors. Because their specification is somewhat differnent I guess the choice is determined by the priorities you have. My 4" Vixen refractor is somewhere between the Tak and the Tele Vue in spec being an F/6.5. From my back garden, which has some light pollution, I can get great wide angle views using the Nagler 31mm eyepiece with showcases such as the Veil Nebula being stunning with an appropriate filter.

If my primary scope had a focal length of 2800mm I think I'd be drawn more towards the faster of the two refractors as a second scope as it would enable such a different perspective on the universe

[ollypenrice]

Ignore the flatness of field with the TV. If you want a flat field you could go for the Tak FSQ106 as an alternative. But flat fields are an imaging issue largely unconnected with visual observing.

The important difference is the F ratio. F8 for the Tak and F5.3 for the TV. In a given EP the TV will give a wider field. I used to have an F5 Pearl River Genesis and the widefield view was staggering, but how much does a bit more field matter to you?

You pay a lot for a flat field and for imaging it can be worth it, but for visual?

Both instruments are brilliant.

Olly

[dweller25]

This may help ......

http://www.cloudynights.com/ubbarchive/showflat.php/Cat/0/Number/1467733/page/0/view/collapsed/sb/9/o/all/fpart/1

It's a long thread - part way down page 13 is where the review starts.....

[IanH]

Hi Guys,

Thanks for the feednback, it really helps.

I will forget the flat field aspect!

With regard to field of view (from the 12dstring website):

So,  a Tak plus a Nagler 31mm - (that still costs  less than the Np101)

Magnification: 26.3x

Field of View: 186.91'

Resolution: 1.35"

The NP101 with my Nagler 20 is

Magnification: 27x Field of View: 182.22' Resolution: 1.37"

I'm guessing this is about as low as I would go under my light pollution anyway, as the targets that need a bigger field are probably too dim.   So, I think this leads me to the Tak as it will go higher more easily (and it's cheaper).   I might regret it if I find myself under an amazing dark sky somewhere - but the chance of that happening in reality is not very big.

The last quesiton - the Tak focuser options - would you go for their own R&P or factory fitted Feathertouch 3" (if it's still available)?

Thanks for all your help.

Ian

[John]

With my Vixen ED102 F/6.5 the 31mm Nagler gives 21x and a true field of 3.8 degrees. Both sides of the Veil Nebula will fit in that FoV and regularly do. One of my favourite sights through a scope and one that I can't get enough of

[IanH]

Hi John,

That sounds great.  Do you think that view is possible under suburban skies, or are you lucky enough to have a pretty dark place to observe from?

Cheers,

Ian

[John]

Hi John,

That sounds great.  Do you think that view is possible under suburban skies, or are you lucky enough to have a pretty dark place to observe from?

Cheers,

Ian

I can get these views from my back garden which has some light pollution from street lights / houses etc. On a good night I can see the milky way across a fair bit of the summer sky and I can see M31, the Andromeda Galaxy with the naked eye, if thats a guide. My NE horizon is affected by the glow from Bristol so I need to wait for objects to rise well above the horizon before it's worth viewing them.

[IanH]

That sounds a bit better than I was thinking.  Your sky is probably darker, but maybe by not that much.  

I have a lot of glow in the east and south, due to London and Slough.  I can just make out Andromeda, the milky way is there as a higher concentration of stars.  The wide view is what I'm after, and it sounds good.

That's sort of what I needed to know I think.

Thanks for youur help.

Ian

[allen g]

I have and the Meade 8" and wanted a companion so as to have wide field views.  I have viewed through both you are considering and bought the np101.  the wide field views are amazing. With my 31 nagler (also have the 21 ethos among other tv eps) I get 4.46* and viewed the entire veil and had a line of observers being Wowed.  I used it in los angeles which is far from pollution free.  keep in mind that it is a quad apo and the quality of the optics are great.  I can go on and on.  I viewed through both and selected the np 101 - I am thrilled with it especially in a grab n go set up.  It is also very solid. 

[Druid]

I've got a C11 and an older TV-101 and the latter is very good indeed, never tried a Tak. 

In my experience, 4" isn't enough under heavy light pollution, except maybe for photography (which I'm still just getting than hang of)

Beautiful scope if you're someplace where you can see the Milky Way though.

Sounds like your light pollution isn't as bad as mine.

[allen g]

Sounds like you are following my footsteps. I asked and researched the same issue beginning of the year. I have a meade LX 90 8" and wanted a quality 4" refractor with wide field views and a grab n go set-up. I read, asked around, and viewed through both scopes among others at star parties that I

attend regularly. Both are top notch scopes so you won't go wrong with either. Both are apos but the np 101 is a quad. the np 101 I recall will

give you wider views which I found amazing for example with a 31 nagler you will get 4.5 degrees. I opted for the TV and to this day extremely happy with my decision. A great solid scope which comes complete scope, diagonal and case (and tube ring). Do put these factors into the decision formular.

[Mogster]

Visually I'd question how satisfying the views will be set up next to your C11. I have an ED80 and other than the few classic large DSO targets everything looks so much better and brighter in my 9.25. Light pollution really kills low power wide field views In my experience.

I'd like a wide field scope but ideally it'd be in the 5" range. For visual use I'd prefer F4-F5 to make it fairly portable, there's nothing like that available with decent quality without paying mega-bucks though. Maybe in a few years.

[IanH]

Well, my other half went and spent the money and more on a second hand flute (£9k - that makes our gear seem cheap). So, I am looking at the other end of the scale now - maybe a Skywatcher Startravel 120 or 150 - I know it is nowhere near the same quality as what we have been discussing, but I am desperate for something that will setup quickly and be compact for carrying in the car. The np101 etc will have to go back on the dream list for a couple of years.

[Space Dragon]

Well, my other half went and spent the money and more on a second hand flute (£9k - that makes our gear seem cheap). So, I am looking at the other end of the scale now - maybe a Skywatcher Startravel 120 or 150 - I know it is nowhere near the same quality as what we have been discussing, but I am desperate for something that will setup quickly and be compact for carrying in the car. The np101 etc will have to go back on the dream list for a couple of years.

Jeez.....£9k on a flute.....you should have got in there first...:-)

However, if you're looking for a cost effective wide field refractor, I can recommend the Kunming 152mm F/5.9. It's sold under various guises, including TS Individual and Lyra Optics. Sold in the US as Astrotelescopes.....see CN for reviews etc.

It costs a little bit more than the standard Chinese fare but is well figured and finished and built like a tank.

You will see CA on the brighter objects but for deep sky and anything less than Mag 4, it is, in my opinion, a great view.

Besides, you have your C11 for high powered, colour free planetary views.

I think you could easily justify the extra.

[L8-Nite]

Get the scope you want anyway. Take out a loan with the flute as collateral; she's going to make a fortune playing the flute.

It's a win win situation.     

[IanH]

:-) thanks for the support. I definitely learned the lesson of spend it while you can....

That 152mm f9 looks like a big beast. I will certainly have a look into it.

I think I am already wondering if 100mm would have been too limited anyway.

So, plenty of ammunition for research and procrastination!

[lensman57]

 

:-) thanks for the support. I definitely learned the lesson of spend it while you can....

That 152mm f9 looks like a big beast. I will certainly have a look into it.

I think I am already wondering if 100mm would have been too limited anyway.

So, plenty of ammunition for research and procrastination!

Why not have a look at the 127mm Apo triplefrom Meade, or Ascension? These are the same scopes BTW. I beleive the Ascension ones carry the test certificates for the optics.  

They are excellent value and the optics are very good. BTW  I see no reason to pay for premimum optics as our skies in the UK are seeing limited, unless you are observing or imaging from a dark site there is no adavantage to be had from having ultra expensive optics.

Regards,

A.G

[IanH]

The issue of our mediocre seeing is one of the things I was wondering about. I love the idea of sharp optics - partly because I now wear glasses for daytime use and much prefer the corrected view to my middle age slightly blurred normal vision. But, when looking through the murk over London (to the east) and Slough (south), I am guessing that super sharpness is unlikely to be available anyway. But in order to make the most of what we can see, do you think a decent triplet such as the Meade would be better than something like the Skywatcher 120ed (or equinox) doublet?

[lensman57]

The issue of our mediocre seeing is one of the things I was wondering about. I love the idea of sharp optics - partly because I now wear glasses for daytime use and much prefer the corrected view to my middle age slightly blurred normal vision. But, when looking through the murk over London (to the east) and Slough (south), I am guessing that super sharpness is unlikely to be available anyway. But in order to make the most of what we can see, do you think a decent triplet such as the Meade would be better than something like the Skywatcher 120ed (or equinox) doublet?

To be honest for observing I doubt very much if you see much difference as the skywatcher 120 as well as the ed100 are well corrected for doublets. I myself were ready to spend a lot more money than I should have on an 80 mm APO for imaging and it was the advice of the shop not to spend so much on the optics as with the horrible LP and seeing in Manchester it would have been a waste of money. Mechanics are however,  something else and I can not stand cheap workmanship, something that I am afraid both my SW scopes suffer from to some extent, and yes I know that they have been built to a price but still..... You may also wish to consider the WO FLTs , these are more expensive than the Meade but they are quite well bult and have very good optics.

Regards,

A.G