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Equipment Discussions >> Refractors

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enniot1
journeyman


Reged: 09/06/10

TELEVUE 102 VS TELEVUE NP101
      #5550703 - 12/02/12 05:20 PM

Hello
My name is Ennio (from Italy). I apologize if I do not write correctly. I need help to choose to buy second hand TV102 or NP101. I read many reviews about these wonderful refractors. I think the NP101 is generally better because it is shorter and correct TV102, but I'm not sure that it is better to see the planets and double stars (sharp and clear) because the TV102 has only two lenses and a longer focal length of the NP101.

Thanks.


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Mr Onions
Two Time International Photographical Competition Winner
*****

Reged: 04/14/07

Loc: Newcastle upon Tyne.
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: enniot1]
      #5550712 - 12/02/12 05:24 PM

Your English is better than my Italian.
Come to think of it, it's better than my English too.

You will get lots of replies from owners of these two very fine refractors.


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snommisbor
scholastic sledgehammer
*****

Reged: 06/15/09

Loc: Cedar Park, TX
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Mr Onions]
      #5550777 - 12/02/12 06:10 PM

If you are visual only the 102 would be better. The 101 is really a scope that its primary function is astrophotography. But if AP is in your future the NP101 is a great scope to have and will work visually when you want to just view the stars. I had the TV101 and it was a great scope. But I was about 80-20 AP to Visual. But if I was visual only the 102 would be what I would get.

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la200o
Carpal Tunnel


Reged: 09/09/08

Loc: SE Michigan, USA
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: snommisbor]
      #5550837 - 12/02/12 06:57 PM

I have both and am entirely visual--no AP. Both are good scopes, but if I had to choose one, it would be the NP101. With the right eyepieces and barlows, you can reach high powers with the 101, but you cannot replicate the wide field views of the 101 with the 102. Sometimes you will read that the 102, being a doublet, is brighter than the 4-lens Petzval 101. This has not been my experience, nor do I find that there is an improvement in contrast with the 102. If you have a choice, go with the NP 101.

Bill

Edited by la200o (12/02/12 06:58 PM)


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stevew
Now I've done it


Reged: 03/03/06

Loc: British Columbia Canada
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: enniot1]
      #5550887 - 12/02/12 07:30 PM

An NP101 with a 30mm Nagler will give you a 4.5 degree true flat field of view. If you have access to very dark skies the views can be incredible.
If you are more interested in the Moon, and Planets go for the less expensive TV102
Both have excellent high contrast optics.

Steve


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la200o
Carpal Tunnel


Reged: 09/09/08

Loc: SE Michigan, USA
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: stevew]
      #5551192 - 12/02/12 10:35 PM

Another advantage of the wide field of the NP101 is that if you use it on an undriven mount (as I do), you can keep your target in the FOV for a longer time without moving the telescope. I think Steve has the right idea; if expense is an issue, the 102 costs less. Otherwise, I see no advantage to the 102. As a doublet, it probably cools down a little faster, but I doubt if that matters much in Italy.

Bill


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Jon Isaacs
Postmaster
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Reged: 06/16/04

Loc: San Diego and Boulevard, CA
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: enniot1]
      #5551430 - 12/03/12 02:44 AM

Quote:

Hello
My name is Ennio (from Italy). I apologize if I do not write correctly. I need help to choose to buy second hand TV102 or NP101. I read many reviews about these wonderful refractors. I think the NP101 is generally better because it is shorter and correct TV102, but I'm not sure that it is better to see the planets and double stars (sharp and clear) because the TV102 has only two lenses and a longer focal length of the NP101.

Thanks.




Ennio:

Hello and Welcome to Cloudy Nights.

I own an NP-101 and I use it for double stars, the planets as well as the low power widefield views that are essentially perfect.

The TV-102 is a basic doublet, if you are interested only in high magnification views, it would be less expensive and offer very similar views. But there are other, even less expensive alternatives one should consider as well as larger scopes that would resolve tighter doubles and provide better planetary views as well.

But for me, the NP-101 is the right scope because I spend a lot of time both under dark skies as well as observing from a light polluted backyard.

Jon


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Erik Bakker
Post Laureate
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Reged: 08/10/06

Loc: The Netherlands, Europe
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: enniot1]
      #5551433 - 12/03/12 02:46 AM

Hi Ennio,

Are you able to see both scopes and test them before you buy them? Together, side-by-side? That will help more to make a good decision than anything else.

The NP101 has superb color correction, wide-flat fields and some I have seen where very well corrected for spherical aberration. They are a bit sensitive for getting out of collimation if you travel a lot with them. But it is a very nice and compact scope. The TV102 has a bit more color, but is fine for visual use. Some have superb spherical correction. The tube is a bit longer than the NP101. The optics in both the NP101 and TV102 are really a sample-sample thing. Test before you buy, none are equal. Some are stunning, get one of those

My FS102 has a very similar focal length to the TV102 and I find it a very versatile scope. For the lowest power widefields I use 2 eyes with my Nikon 18x70 bino. With the FS102 I start mono at 37x with my 22mm Nagler T4. The best medium power views are with the Zeiss 16.7 and 12.8 WW eyepieces. For more power than that, I switch to binoviewing. For the planets, I only observe with 2 eyes.

There was also a shorter version of the TV102, the last were named TV102is. Shorter and very well suited for bino-viewing.

Short answer: buy the best sample of the NP101/TV102 you are looking at. It will make you a very happy astronomer


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enniot1
journeyman


Reged: 09/06/10

Re: TELEVUE 102 VS TELEVUE NP101 new [Re: stevew]
      #5551460 - 12/03/12 03:16 AM

Thank you all for the answers. Tele Vue and AP have been a reference for lovers of astronomy in Italy and I think all over the world (maybe not for younger generations), so owning one of these telescopes is already a great privilege for me. We know that today there are other telescopes like the TSA 102 that are at the top and as color correction and as sharpness (perhaps unbeatable) but I think that a telescope, as well as the optical quality has to try the feelings when we look inside. (I do not know how to explain it).
In Italy, unfortunately, the cost of telescopes is very high, for example, now TVnp101 costs € 4,500, while the TSA 102 (depending on the accessories) costs between 3,300 and 3,700 Euros.
I found a TV102 with reducer / flattener and accessories to € 2,000, while a TV np101 to € 2500, but before I spend the money I would be sure to choose well.
I like TeleVue because I think he has a special charm as well as a good mechanic.
Italy is a small area but very varied, so we are seeing some good areas and other areas where the seeing is average, 5-6. It 'amazing how seeing is different after a few miles away. From a friend of mine who lives on the far outskirts of Rome, for example, Mars was still and the seeing was 8-9. When I went immediately to my house, at a distance of a few kilometers, the seeing was average 5-6.

Thanks to all.


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enniot1
journeyman


Reged: 09/06/10

Re: TELEVUE 102 VS TELEVUE NP101 new [Re: la200o]
      #5551652 - 12/03/12 08:36 AM

For la200 and Jon Isaacs that have NP101.
I understand that some NP101, have different diffraction images. Rings in intra focal images are clear, but in the extra focal images rings can not be seen clearly.
May depend on the optical design or is spherical aberration?


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enniot1
journeyman


Reged: 09/06/10

Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Erik Bakker]
      #5551656 - 12/03/12 08:38 AM

Hi Erik, maybe I can try the TV102 but not the NP101.

Thanks.


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la200o
Carpal Tunnel


Reged: 09/09/08

Loc: SE Michigan, USA
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: enniot1]
      #5551934 - 12/03/12 12:19 PM

Quote:

For la200 and Jon Isaacs that have NP101.
I understand that some NP101, have different diffraction images. Rings in intra focal images are clear, but in the extra focal images rings can not be seen clearly.
May depend on the optical design or is spherical aberration?




I haven't heard about this; I did read somewhere that one owner (who greatly liked his NP101) thought he detected some spherical abberration, but then attributed it to the telescope not being properly cooled down when he began to observe.

Every now and then you will read about collimation issues with the more complex NP101, but I don't think collimation is a common problem. Tele Vue has been making Petzvals for a long time and has the bugs, if any, pretty much worked out. Both 101 and 102 are fine scopes, though, and you won't be making a mistake with either.

Bill


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Scott BeithAdministrator
SRF
*****

Reged: 11/26/03

Loc: Frederick, MD
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: la200o]
      #5552004 - 12/03/12 12:51 PM

I have never owned either scope but years ago I was given the opportunity to run a Tak FS102 side by side with a TV NP101. Targets such as Jupiter (high mags) and the DC (low mags) were selected. After many back and forth observations the NP101 edged out the FS102 (but it was REALLY close). This was only with one sample of each scope and might not be indicative of results obtained from a larger pool of samples. I would be thrilled to own either the TV102 (which should be right in line with my SV102V LOMO) or the NP101 if I didn't already have the SV.

A high quality 4" apo is a heck of a nice scope.

Either way you will be happy.


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jrbarnett
Eyepiece Hooligan
*****

Reged: 02/28/06

Loc: Petaluma, CA
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: enniot1]
      #5552019 - 12/03/12 01:01 PM

Ennio:

For visual use as you describe, I would go with the TV-102. The TV-102 is less sensitive to alignment and centering errors, cools more quickly, has greater depth of focus, costs less, holds its value better used, doesn't require Barlows to achieve highest useful magnification, has little field curvature visually at a slow f/8.6 and actually weighs a bit less. Likewise, the NP-101 is not a short scope. Because it's a Petzval, it is much longer than a 101mm f/5.4 doublet would be, and is only a little shorter than the TV-102.

Unless you are a nut for ultra wide true fields of view, I can't see much reason to invest in an NP-101 as a visual use instrument. If you do buy an NP-101, though, buy used. They depreciate enormously from new.

Regards,

Jim

Edited by jrbarnett (12/03/12 03:06 PM)


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Jim Romanski
Carpal Tunnel
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Reged: 01/02/05

Loc: Guilford, Connecticut
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: enniot1]
      #5552026 - 12/03/12 01:06 PM

I want to make sure that some of the previous posts are not lost in translation. Folks here on CN (Cloudynights) tend to abbreviate quite a lot.

When someone writes "80-20 AP to Visual" they are saying that 80% of the time they use the telescope for AP (Astrophotography) and 20% of the time to look through it visually.

They are NOT referring to AP (Astrophysics) Refractor Telescopes.

I have an NP101 and it's a wonderful versatile telescope. I can see wide fields and high power. I can also do widefield Astrophotography with it if I wish.

The TV102 is very well corrected for false color but not as good as the NP101. Other than that the main difference is that you won't get quite as wide a field of view with it.


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enniot1
journeyman


Reged: 09/06/10

Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Jim Romanski]
      #5552403 - 12/03/12 04:57 PM Attachment (41 downloads)

This is one of a star test NP101. As you can see the pictures intra / extra are very different.

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enniot1
journeyman


Reged: 09/06/10

Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Erik Bakker]
      #5552433 - 12/03/12 05:12 PM

You're right Erik, perhaps the Televue are not all the same, because here in Italy I heard positive feedback but also negative. It's possible?

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John Rhodes
Vendor (Televue Rep)
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Reged: 02/21/06

Loc: Torrance, CA.
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: enniot1]
      #5552581 - 12/03/12 06:45 PM

Quote:

This is one of a star test NP101. As you can see the pictures intra / extra are very different.



This picture is in no way indicative of an NP 101, or NP 101is
I have had several and currently have two (one of each) that I use at star parties and
I can get near if not identical diffraction patterns on each side of focus visually.

Edited by Tigerider (12/03/12 06:57 PM)


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la200o
Carpal Tunnel


Reged: 09/09/08

Loc: SE Michigan, USA
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: John Rhodes]
      #5552629 - 12/03/12 07:13 PM

Maybe I'm repeating myself, but I own both and if I had to choose I'd take the NP101 in an instant and sell the 102. Don't really know why I keep the 102, except that I don't need the money, like having a backup scope, and am sentimentally attached to the old 102, which was my first good 4" refractor. The collimation problems have been IMO exaggerated and I find the NP101, despite its shallower depth of field, just fine even with the older one-speed focuser (and now of course it comes with a really good two-speed). Cool down will not be much of an issue. Although any mount that will handle the 102 will handle the 101 and vice versa, I find the shorter tube of the 101 a better match for the mount I use for them (a Half Hitch Mark III).

Jim Barnett is certainly right that it can be very advantageous to buy used, since depreciation is considerable, but with the notable exception of Astrophysics telescopes, this is pretty true of apo's in general. I haven't followed TEC prices much, but Tak FS and TSA 4" scopes depreciate significantly as well, though there are fewer of them out there and therefore harder to find used.

Here's how I see it: TV 102, cheaper than the 101, and that's about it as far as real advantages go. Will you notice a great difference visually with the NP101? Probably not, but you will lose the (to me) great advantage of the NP's wide, flat field (unbeatable for open clusters), the essentially perfect color correction of that scope (not that the 102 is at all bad), and the knowledge that you've got the best telescope that TV has produced so far.

But again, you can't really go wrong. I used and continue to use my 102 with great satisfaction.

Bill


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jrbarnett
Eyepiece Hooligan
*****

Reged: 02/28/06

Loc: Petaluma, CA
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: enniot1]
      #5552746 - 12/03/12 08:18 PM

That's not all that unique or unusual for a Televue Petzval's star test.

See these NP-127 images showing similar softness on one side of focus.

http://tinyurl.com/czzsgo9

Disregard the folks blaming seeing. Seeing affects BOTH SIDES OF FOCUS. Only one side of this optic is really soft.

Peruse these, too:

http://aberrator.astronomy.net/scopetest/

See this example specifically:

http://aberrator.astronomy.net/scopetest/html/refractor100_4.html

There are mixed bag results for TV-102s, too, though. I've owned one and looked through a bunch of TV-102s, and all are not created equally. Rohr has a test for one with a zone. It's still a decent optic in the final analysis, but not as good as other TV-102s. It's worth noting, though, that I've seen more "middlin" Televue Petzvals than doublets. That's not to say that I haven't seen Televue Petszals with nice optics too. I have. Two out of six that I've had a chance to play with and star test a bit. It was my experiences with other people's NPs that lead me to opt for the doublet instead.

Regards,

Jim


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la200o
Carpal Tunnel


Reged: 09/09/08

Loc: SE Michigan, USA
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: jrbarnett]
      #5552866 - 12/03/12 09:20 PM

Though he may not be a fan, Jim seems to be outvoted by the many favorable reviews and enthusiastic users of the NP101.

Bill


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cloud_cover
professor emeritus


Reged: 08/17/10

Loc: Restaurant at the End of the U...
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: la200o]
      #5553123 - 12/03/12 11:46 PM

Hello!
I think the most important question is do you ever intend to stick a camera into the telescope? If yes, then the NP-101 is the best choice (actually the only choice unless you like to play with field flatteners, which adds cost to your whole setup anyway)
I personally use the NP-101 for both visual and AP. I find its contrast is excellent and looking at stars through it is almost sublime, compared with a previous 80ED doublet I had an a current 8" SCT (The SCT is undoubtedly brighter, but the NP-101 view is nicer)
I'd also like to point out that although the TV-101 has a longer focal length, this difference can be compensated for by using shorter focal length eyepieces. They both have (roughly) the same maximum useful magnification anyway)
How much is the difference in price, used? If its not significant, then I suggest going for the NP-101 instead.


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KWB
Postmaster
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Reged: 09/30/06

Loc: Westminster,Co Elev.5400 feet
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: la200o]
      #5553148 - 12/04/12 12:01 AM

Quote:

Though he may not be a fan, Jim seems to be outvoted by the many favorable reviews and enthusiastic users of the NP101.

Bill



Everybody is entitled to their opinion,and no, we aren't running an election in this thread,nor do we need to make reference to anothers likes or dislikes. One persons eye for beauty can be anothers eyesore.

Stating your viewpoint once, on-topic and in a civil manner, in a thread is usually sufficient.


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la200o
Carpal Tunnel


Reged: 09/09/08

Loc: SE Michigan, USA
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: KWB]
      #5553495 - 12/04/12 07:58 AM

I fail to see how my comment is uncivil.

Regards,

Bill

Edited by la200o (12/04/12 08:02 AM)


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Lt 26
scholastic sledgehammer
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Reged: 02/19/09

Loc: Northwest Illinois
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: KWB]
      #5553501 - 12/04/12 08:01 AM

1) the 102 cost less, a lot less new, a few Ethos less.

2) the 102 is shorter and lighter than a 101 with a Barlow.

3) you can drop kick a 102 across a field and the only damage would be to your foot.

Dereck


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la200o
Carpal Tunnel


Reged: 09/09/08

Loc: SE Michigan, USA
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Lt 26]
      #5553504 - 12/04/12 08:04 AM

Dereck, alas, you can't buy new 102, since the scope's been discontinued.

Bill


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NHRob
Post Laureate
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Reged: 08/27/04

Loc: New Hampshire
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: la200o]
      #5553615 - 12/04/12 09:23 AM

Also, using a TV-102 has been shown to:

* increase male virility
* stop hair loss
* increase stamina and energy level
* contribute to fat loss
* improve memory function

and also lead to a general feeling of well being.




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la200o
Carpal Tunnel


Reged: 09/09/08

Loc: SE Michigan, USA
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: NHRob]
      #5553650 - 12/04/12 09:50 AM

Rob, you've given me more reasons not to sell my 102!

Bill


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Jon Isaacs
Postmaster
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Reged: 06/16/04

Loc: San Diego and Boulevard, CA
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Lt 26]
      #5553666 - 12/04/12 10:00 AM

Quote:



2) the 102 is shorter and lighter than a 101 with a Barlow.






I put the Barlow in the diagonal, the length of NP-101 does not change. The Barlow weighs 76 grams.

Besides being more compact, the big thing about the NP-101 is that it does it all, 15x to 300x with zero field curvature at the low end and perfect color correction at the high end.

Sure the TV-102 represents a better value, the Synta ED-100s are much better values than either scope. In this price range, I suspect one is looking for the better scope and the NP-101 is the better scope.

Jon


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la200o
Carpal Tunnel


Reged: 09/09/08

Loc: SE Michigan, USA
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Jon Isaacs]
      #5553720 - 12/04/12 10:39 AM

+1

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stratocaster
sage
*****

Reged: 10/27/11

Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Jon Isaacs]
      #5553889 - 12/04/12 12:32 PM

Quote:

...the big thing about the NP-101 is that it does it all, 15x to 300x with zero field curvature...




Jon, I've started to notice what I'm now considering inevitable FC in my refractor using 100 degree eyepieces as a "typical" fundamental refractor design issue - not unlike coma in a reflector. But I remember you mentioning in previous threads that you have no field curvature with the NP101 and I always wondered what it was about the 101's design that eliminated FC that might be considered "not typical". In this thread it appears the NP101 was designed more for imaging. Is this why the 101 has no FC - because it has already been corrected for AP use while perhaps most other refractors require a field flattener?


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Jon Isaacs
Postmaster
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Reged: 06/16/04

Loc: San Diego and Boulevard, CA
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: stratocaster]
      #5554028 - 12/04/12 01:45 PM

The NP-101 is designed for visual and photography. NP stands for Nagler-Petzval. A Petzval is a 4 element design that has two groups of two element,one at the front one, in the rear.

The NP-101 is the most recent offering in a long line of TeleVue Petzval refractors that include the MPT, the various versions of the Genesis and the TV-101. Uncle Al loves big, widefield views and combined with his eyepieces, the NP -101 is about as perfect as it gets.

jon


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Mr Onions
Two Time International Photographical Competition Winner
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Reged: 04/14/07

Loc: Newcastle upon Tyne.
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Jon Isaacs]
      #5554063 - 12/04/12 02:08 PM

The shorter tube of the NP 101 might make it easier when viewing directly overhead at the zenith,depending on your mount of course.
And you might split tight doubles easier at very high powers with the NP101.
Although you're probably talking 200x+ to see an advantage.


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jrbarnett
Eyepiece Hooligan
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Reged: 02/28/06

Loc: Petaluma, CA
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: la200o]
      #5554185 - 12/04/12 03:37 PM

I take great solace in being outvoted, Bill. After all, the majority of our countrymen believe in all sorts of superstitious nonsense that isn't true. For example, more Americans believe that the world will end on December 21 of this year due to a Maya prophecy than can identify North America on a globe.

- Jim


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snommisbor
scholastic sledgehammer
*****

Reged: 06/15/09

Loc: Cedar Park, TX
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: jrbarnett]
      #5554223 - 12/04/12 04:15 PM

I hear ya Jim, I felt the same way LOL. I thought for visual only people would recommend the 102 as I did. The NP101 is great I had its predecessor and the views were great but I needed the more powerful EP's to get close. But since I used it mainly for AP I just enjoyed my 13 Ethos at 40X and 7 Nagler at 77X. Still waiting for that TEC 140 to come in. Being without a scope has me going through withdrawals.

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sydney
super member


Reged: 04/07/10

Loc: Upstate NY
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: enniot1]
      #5554356 - 12/04/12 05:52 PM

Roland Christen wrote in "Notes on Star Testing Telescopes"

"Every Apo lens I have ever star tested, even ones that tested close to 1/20 wave P-V, shows different inside and outside patterns of interference. This is normal...

... If the outer rings are identical on either side of focus, there is no significant spherical aberration."

http://geogdata.csun.edu/~voltaire/roland/startest1.html

Al Nagler once told me that about the outer ring as well for testing a refractor.

p.s there is nothing like the wide field view through an NP101/NP101is.


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jrbarnett
Eyepiece Hooligan
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Reged: 02/28/06

Loc: Petaluma, CA
Re: TELEVUE 102 VS TELEVUE NP101 new [Re: sydney]
      #5554454 - 12/04/12 06:57 PM

I'm pretty sure that Roland is talking about triplets, not doublets. He doesn't consider doublets "apochromats".

The NP is a doublet with a corrector set in the rear. It should, as Televue employee tigerider claims on this thread, show a perfectly symmetrical star test if perfect, just like any other doublet.

Regards,

Jim

Edited by jrbarnett (12/04/12 06:59 PM)


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la200o
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: jrbarnett]
      #5554512 - 12/04/12 07:39 PM

Jim, are the FSQ's also "doublets"?

Regards,
Bill

p.s. This will all be moot on Dec 22d anyway!


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idealistic
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: la200o]
      #5554529 - 12/04/12 07:45 PM

"Double doublets"

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Levine
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: idealistic]
      #5554573 - 12/04/12 08:17 PM

Quote:

"Double doublets"




Quadruplet!



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Sky Muse
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Levine]
      #5554944 - 12/05/12 12:54 AM

I remember coming across advertisements of Unk Al's petzval with its suspicious, presumably photon-absorptive, dual-doublet design, and back in 2003 when I chose a single, fluorite, Fraunhofer doublet instead...

...and overwhelmingly.

I suppose if my FS-102 unexpectedly, I'd have to go with the TV-102.

Simpler is simply better.

Cheers,

Alan


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Jon Isaacs
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Sky Muse]
      #5555212 - 12/05/12 07:22 AM

Quote:

Simpler is simply better.




If simpler is better, then an Aerial scope would seem to be your best bet. But, it doesn't quite work that way. A well corrected view requires more than 2 elements.

And of course, Newtonians and simpler than refractors since their is no dispersion and they only have one curved surface and one flat whereas a modern refractor has a minimum of 4 curved surfaces. Color correction is simple with mirrors.

If one is OK with maybe some chromatic aberration and/or significant field curvature, there are a lot of choices... Otherwise, it's pretty much the NP-101 or maybe the FSQ-106.

Jon


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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Jon Isaacs]
      #5555525 - 12/05/12 11:30 AM

I'm with Jon

If simple was better then why not a single lens?

The TV102 is a very nice scope and a pretty good value. But simply put, the NP101 is unequalled in image quality across the field. You can look at planets in high power or sweep through the milky way and gaze a star clusters and star clouds with razor sharp pinpoint images.

I always thought I knew what pinpoint star images looked like. But after owning an NP101 my perspective changed. I bought the scope thinking I might do some imaging and while I still might it doesn't matter. The quality of the image across the entire field is just that good. Wish they made and I could afford an 8" NP scope.


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cloud_cover
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Levine]
      #5555548 - 12/05/12 11:52 AM

I really don't understand the NP-101 bashing that's going on. What's not to like about it? Perhaps its too expensive for good taste, or for a 4" refractor?
1. Regarding collimation: It is a small matter to fix. I dropped my scope resulting in gross mis-collimation. Incidentally it was a good thing the lenses remained intact. I managed to fix it without making any jigs, within 1 hour, in the daytime, indoors, with the use of a $25 Hubble Artificial Star. It now produces the usual perfect pinpoint stars again.
2. Regarding "planetary magnification": the resolving power of a telescope is dependent of the aperture, not the focal length. Even if you have a fast scope, you can get the same magnification by using shorter eyepieces. Besides, even if you adhere to the rule for maximal useful magnification of "50x per inch", this will give "only" 200x on both the 101 and 102, which is exceeded on the NP-101 by a 2.5mm eyepiece. In practice I use a E3.7mm plus GSO 2x barlow as seeing allows.
3. The dreaded Petzval design: It flattens the field for photography and widefield viewing. This is advantageous. Collimation, as above, is a small matter.
4. Complicated design: Even if the lenses allowed "only" 98% light transmission, it would lose about 4% as compared to a similarly specced doublet, but the doublet is likely to be less well corrected for color, which is one of the strengths of the NP-101. It is doubtful that the 4% can be perceived by an observer, and then probably only under the most stringent conditions and side-by-side.

I have to agree with Jon: If the strengths of the NP-101 are of value to the OP, then it is a truly worthy purchase. On the other hand, if the price/value ratio of the 102 is more appealing, then for that money the OP can probably do better with another telescope brand, which is also probably why the 102 was discontinued: It was no longer competitive.


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la200o
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: cloud_cover]
      #5555552 - 12/05/12 12:00 PM

The NP101 is the most versitile 4" refractor out there. Period. Paragraph.

Bill


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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: la200o]
      #5555808 - 12/05/12 02:57 PM

Yes. Though the FSQ design differs from the NP design which has a doublet and a doublet layout, I believe.

The FSQ is a doublet, singlet, singlet layout.

http://www.takahashi-europe.com/images/products/fsq106ed/700/FSQ-106ED_lightp...

- Jim


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Sky Muse
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Jim Romanski]
      #5555845 - 12/05/12 03:21 PM

"If simple was better then why not a single lens?"

...of course not, barring a giddy incarnation of Galileo.

"You can look at planets in high power or sweep through the milky way and gaze a star clusters and star clouds with razor sharp pinpoint images."

Though with only slight improvement, if that, over a superb doublet, and in exchange for what, qualities bespoken of another...

http://www.takahashi-europe.com/en/FSQ-106ED.php ...?

Oh, and the corrector permanently chambered, again, photon-absorptive, yet only modestly corrective. Then, we have the literature, opposed to that in favourable appraisal...

http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/5421558/Main...

http://www.singastro.org/forum2/viewtopic.php?f=3&t=9660&start=10

Upon decision, the greater of the two, and without the secondary; why, it's challenged, and alluding to contraptive, mirrored arrangements, not to mention the primary unable to function independently of the corrector...

http://www.company7.com/televue/telescopes/tvnp101.html

Then we have this, accompanied by the glossy accolades and glowing testimonials for its time, for those TeleVue enthusiasts so inclined...

http://www.google.com/imgres?q=Televue+TV-102&um=1&hl=en&sa=N&...

...despite its glint, I remember, though deciding in favour of sublime subtlety.

On the other hand, if one is not prone to drop the other?

Cheers,

Alan


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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Sky Muse]
      #5555894 - 12/05/12 03:56 PM

Quote:

...of course not, barring a giddy incarnation of Galileo.




So simpler is not necessarily better.

Quote:

Though with only slight improvement, if that, over a superb doublet, and in exchange for what, qualities bespoken of another...




Not really... a doublet that is capable of a 4.5 degree TFoV has significant field curvature. This is what the NP-101 does that the others don't...

If you want a 4 inch F/9 doublet, if that will fill your needs, there are many choices, the TV-102 is a good one but it's one of several. But TeleVue is known for innovation. Widefield eyepieces that are free from astigmatism in fast telescopes, refractors that offer wide flat fields and with the NP-101, perfect color correction.... it's the one if you want an example of TeleVue's best work.

Jon Isaacs

(P.S.: Honestly, I find the single sentences of vague and obscure wordings followed by a link incomprehensible. I am not going to make the effort to read though a page to try to figure out what you are talking about.)


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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Jim Romanski]
      #5555909 - 12/05/12 04:05 PM

"But simply put, the NP101 is unequalled in image quality across the field."

Rather it depends on the NP-101 you happen to get and the TV-102 you happen to be comparing it to. I've seen good ones and not so good ones of each. A good one of either design surpasses the image quality of a less good one of the other design.

The NP design is *much* more sensitive to misalignment and performance suffers significantly more if the front double is out of whack relative to the rear, fixed elements.

I suspect the poor performing NP-101s I've used over the years were probably due to out of whack optics. (I've never seen any Vixen NA140, for instance, that wasn't miscollimated from the factory. Some of those are a lot worse than others, too.)

Ever heard of anyone needing to construct a collimation jig for his TV-102? Me either. And there's a reason. The TV-102 has to be really borked in collimation for the image quality to suffer. The NP-101 suffers if the alignment is only slightly borked.

Regards,

Jim


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enniot1
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Jon Isaacs]
      #5555953 - 12/05/12 04:31 PM

Unfortunately I think it is difficult in general to determine what is the best telescope. Of course, the NP101 has a better color correction and costs more than TV102. I've also heard many opinions on the Tak FS102, that is better than the TV102, and that during a test between NP101 and Taka FS102, Jupiter in Taka saw the bands but not seen in the NP101. The next day the owner dell'NP101 put it for sale.

SECONDHAND costs IN ITALY - TAKA FS102 € 1600/1800
TV102 (Is not easy to found it)€ 2000
WITH FOCAL REDUCER
NP 101 € 2300 / 2500

What do you think about this test? I don't know if you can translate it, but it's interesting.

http://www.sidus.org/proveStrumenti/telescopi/pigmei.html

Thanks to all
Ennio


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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: jrbarnett]
      #5555975 - 12/05/12 04:48 PM

Quote:

"But simply put, the NP101 is unequalled in image quality across the field."

Rather it depends on the NP-101 you happen to get and the TV-102 you happen to be comparing it to. I've seen good ones and not so good ones of each. A good one of either design surpasses the image quality of a less good one of the other design.

The NP design is *much* more sensitive to misalignment and performance suffers significantly more if the front double is out of whack relative to the rear, fixed elements.

I suspect the poor performing NP-101s I've used over the years were probably due to out of whack optics. (I've never seen any Vixen NA140, for instance, that wasn't miscollimated from the factory. Some of those are a lot worse than others, too.)

Ever heard of anyone needing to construct a collimation jig for his TV-102? Me either. And there's a reason. The TV-102 has to be really borked in collimation for the image quality to suffer. The NP-101 suffers if the alignment is only slightly borked.

Regards,

Jim




Just to be clear:

I built a collimation jig for my NP-101 because the in-focus diffraction rings were not uniform around a star at 300x. In terms of "image quality across the field of view", the miscollimation was not visible at lower magnifications, particularly those where the field curvature of a doublet would affect the "image quality quality across the field."

The NP-101 is not the right scope for everyone. If a flat 4.5 degree TFoV or even a flat 2.5 degree TFoV is of interest.. it is the one.

I am always a bit perplexed why there is so much attention paid to the planetary and double star views of various 4 inch refractors when these views are not the strong points of a 4 inch. There are a variety of other scopes of a variety of designs that provide superior high power views to even a perfect 4 inch refractor.

What a 4 inch refractor does that other scopes cannot, wide, bright, big, low magnification views. You can't get those any other way. At doing what 4 inch refractors do best, the NP-101 is the best...

'nuff said.

Jon


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Sky Muse
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Jon Isaacs]
      #5556139 - 12/05/12 06:27 PM

"...and with the NP-101, perfect color correction.... it's the one if you want an example of TeleVue's best work."

...rather, best attempt, and only if it's babied.

"...to try to figure out what you are talking about.)"

Here...

"Also do take note the Petzval design is more susceptible to miscollimation and there have been owner complaints on focuser slop in the NP-101." - cloud_cover

I'd hate having to collimate, in case of an accident, where just right before one is heard in angst, "Oh my God!"

I wouldn't care for a sloppy focuser, either.

I do find it commendable, however, that you have undertaken considerable effort to improve upon it.

Cheers,

Alan


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la200o
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Sky Muse]
      #5556226 - 12/05/12 07:10 PM

I'm not sure I entirely follow this, but if I do, I'd put in that there is certainly nothing "sloppy' about the TV focuser; far from it. Some find the older one-speed focuser hard to bring to focus in an f5.4 scope. Sure not sloppy, tho'.

As far as collimation is concerned, there are threads about this now and then, and plenty of NP101 owners (and of the several similar models that preceded it) have never had a problem with it, including myself.

There is no 4" apo that can do all the things the NP101 can do, and I'm not convinced that there are any that do anything notably better. The only fault I can find with mine is that it's not an NP127.

Clear skies,
Bill


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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: jrbarnett]
      #5556315 - 12/05/12 07:58 PM

Quote:


The NP design is *much* more sensitive to misalignment and performance suffers significantly more if the front double is out of whack relative to the rear, fixed elements.

Jim




Just not true... the NP101 and the TV 102 have the same tube except for length, the same front cell, and two elements up front.
It would take the same "pressure" (bump) to knock them out of collimation and both just need to be tilted back in to collimation.

I've done it several times on a CG-5 mount in my garage ! using a light on a .5 in ball bearing @ about 30 feet, @ up to 600 X.
The rear elements do not, cannot move. The only difference is the faster focal ratio which I haven't noticed to be a problem at all.


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mountain monk
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: John Rhodes]
      #5556445 - 12/05/12 09:17 PM

Thank you for that information, John. I sure love my NP-101, especially with the Feather Touch upgrade.

Dark skies.

Jack


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cloud_cover
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: enniot1]
      #5556602 - 12/05/12 10:45 PM

Quote:


What do you think about this test? I don't know if you can translate it, but it's interesting.

http://www.sidus.org/proveStrumenti/telescopi/pigmei.html

Thanks to all
Ennio




Here ya go. Its translated with Google so it may be inaccurate but I think it gies a decent idea.

Tests Telescopes
THE NIGHT OF THE CHILDREN EXPENSIVE
TeleVue NP101 vs. Takahashi FS102 vs. Vixen ED102SS
(by R. Deckard)
Try this bad .... with many expectations and MANY surprises.

Necessary introduction ... :

- Proof refers to one evening and then valutatela for and what ';
- this test is not 'the sum of the evidence of the three telescopes ... but it 's only a comparative;
- in some ways surprising results were confirmed me in a low voice to different people ... but ... sssshhh .... you can not 'say out loud!

The contenders :

Vixen ED102SS give 102 F660 f6.6 (about 2100eu)

the Televue NP101 give 101 F560 F5.4 (a Panda used)

The taka give FS102 F860 102 f8 (2300eu about).

Seeing good, slightly higher than normal but not perfect. Good transparency for what can 'be a clear sky of the plains.

Watch out!

VENUS on the issue and 'now very clear, the Tak and the TV are pretty much in the same way as the Vx suffers from the residual chromatism, little, little annoying but still unmistakably present. For the rest of Venus there 'a tube to see and so it' easy to get even, colors separately.

Round 1: Tak, TV, Vx. With Vx far from the first two.

Let's move on SATURN, Tak and TV still on par with Vx recovering sensational, on the other hand we know that Venus' *BLEEP* ... The image and 'very slightly lower as cleaning but think of the difference in price between Vx and TV shudder. That is, if someone tells me that it's worth it give him a tapir. Alive. On TV 200x begin to appear some sparkle colorful ... perhaps seeing but in any case the Tak and Vx are neutral even if the vx and 'a little' less neutral than others.

Round 2: Tak, TV, Vx but if you think that with the money requested in Italy for the TV you can buy almost 3 Vx take the TV and use it as a golf club.

Go with DEEP ... a quick rundown of M37, M34, 35 and 36. beautiful, however, even though the stars of the TV are made of "star" while the dots are tak. I do not know if I can explain, I think we are in psicoottica more 'than anything else ... cmq both me and the owner of the TV it is understood that they are the most 'beautiful ones of tak ... The Vx does his job but it 'a bit' more '"dirty" at the edges, regardless of the eyepiece.

The centric of Vx are questionable, different intra kneaded, blurred the last link, and slightly astigmatic. skifo one then? wait ... that there 'to laugh ...

Of the centric tak are perfect. point. not perfect so to speak, to say something is not perfect, are perfect REALLY. only a very slight magenta hue on the one hand, very slight and the SE know see.

The Centric TV's are by no means perfect as you read. the intra and 'perfect but the extra' sa bit different and more 'mixed, slightly tinged by both parties. That's *BLEEP* to say that the TV 's perfect as written on S & T, the TV has its flaws beautiful ... as the focal ratio was assumed to another.

Anyway at this point of the trial Tak TV and substantially in practical use are the same and therefore argue in favor of the TV focuser (cmq difficult to make fire by dell'f5), the retractable hood and a better finish in general , play against the TV the price asked by Carnival in Italy. Among other things, the TV is not 'much more' smaller Tak it 'much more' light.

But 'now comes the fun part ... JUPITER ... so far we joked ... Venus and 'a false target, with a 100mm deep and' almost a waste of time ... but the Moon and Jupiter ... high resolution ... sparrows are usually bitter ... The moon is not there '.... There accentiamo of Jupiter ...

Well ... steep fall of the TV ... two festoons disappear, you can see the fatigue ... in Tak and seen enough, without hesitation .. and this could not expect him to see that one and 'a f8 and the other a f5 but ... you want the twist ...? The TV takes the pay from Vx ... streamers are best visible in the Vx ... the planet and 'slightly stained yellow while in the TV' s perfect TV but in the two streamers are really hard while we are in Vx though not as clearly as in Tak ...

I'll save the face of my friend (who fortunately and 'also the owner of tak 102, my ex) ... I only say that when he put everything back in the car and 'party forgetting the TV in my garden ...

I am a bit 'confused by this test and then not do' comments it 'will draw' conclusions. But 'if you were not so' cautious and sober I would say that the Tak and 'absolutely the best piece of glass I have ever seen, more than on high resolution TV without a shadow of a doubt, the TV and' a product that knows a lot about "American" ... beautiful as this ... "You know and 'stuff ... American uauh .... and then it costs a lot .... a-re-uauh ...", but the evidence shows a telescope normal for this class of quality' at a cost picturesque altino in Italy and also in the USA, the Vx simply makes miracles ...


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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: enniot1]
      #5556877 - 12/06/12 04:22 AM

Hi Ennio,

In the samples I have seen, the Tak FS102 has unsurpassed optics for visual high power use. And the NSV version (2004/2005) is substantially shorter than the fixed dewcap older FS. For the planets, an FS102 NSV IMHO will be the best of those 3 scopes. What mine shows on Jupiter in the BinoVue at 131x-173x is absolutely stunning. So much detail in the wake of the GRS and the rest of the planet. Keeps me busy for hours!

For wide fields and A-P: the NP101 can't be beat. And it is a beauty too.

Like I said before: let the specific quality of the specific sample of a scope decide which of these you choose. A superb sample of any of these scopes will serve you very well.

Edited by Erik Bakker (12/06/12 09:43 AM)


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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Sky Muse]
      #5556996 - 12/06/12 07:44 AM

Quote:

"Also do take note the Petzval design is more susceptible to miscollimation and there have been owner complaints on focuser slop in the NP-101." - cloud_cover




I have never seen any complaints about focuser slop in the NP-101, the previous owner upgraded mine with the Feathertouch micro-focuser, it is the best focuser I have ever used.

I am wondering how much time you have spent looking through an NP-101? To really know on a scope, it's hard to do without some eyepiece time...

I also wonder why this thread seems to have transformed into a comparison of the NP-101 and various other doublets. The original poster was interested in the NP-101 vs the TV-102.

Jon

Edited by Jon Isaacs (12/06/12 08:00 AM)


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la200o
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Jon Isaacs]
      #5557102 - 12/06/12 09:05 AM

I too wonder how the thread has morphed into attack and defense of the NP101. I also wonder why the NP101 attracts such animosity from some quarters, since there are so many happy users and rave reviews of the scope out there. Do you suppose the OP has gotten what he hoped for from this thread? Probably not. . .

But hey, one more time Ennio: Both great scopes! Good luck with your decision. Most likely you'll be very happy with either one.

Bill

Edited by la200o (12/06/12 09:32 AM)


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cloud_cover
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Jon Isaacs]
      #5557176 - 12/06/12 09:58 AM

Quote:

Quote:

"Also do take note the Petzval design is more susceptible to miscollimation and there have been owner complaints on focuser slop in the NP-101." - cloud_cover




I have never seen any complaints about focuser slop in the NP-101, the previous owner upgraded mine with the Feathertouch micro-focuser, it is the best focuser I have ever used.

I am wondering how much time you have spent looking through an NP-101? To really know on a scope, it's hard to do without some eyepiece time...

I also wonder why this thread seems to have transformed into a comparison of the NP-101 and various other doublets. The original poster was interested in the NP-101 vs the TV-102.

Jon




My words have come back to haunt me...

The above was posted in my home club's forum. They are based on a PM I received from an NP-101 user who's focusmate I was trying to buy, prior to receiving my NP-101. He cautioned me about the focuser slipping especially when mounting heavy camera loads. There is a reason why I would be extra cautious in pointing out a scope's possible faults when recommending one in my home club's forum: I might well have to meet the person regularly during events and have no wish to have someone accuse, or think of me as misleading.
In my own experience, I have mounted a 2kg camera with an extra 2kg of ice wrapped around it without any issues. No focuser slipping, no shift in the critical focus needed for imaging. Bhatinov images before and after the imaging session - exactly the same. Nevermind eyepiece time Jon, I don't have a 4kg eyepiece nor does my eye have the resolving power of a CCD
Incidentally it fell 1.5m onto a hard concrete floor, smashing the micro-focus side of the FT focuser. The focuser tube itself and the R&P mechanism are working just as fine without any sticking or roughness. That says a lot about the fine build of the scope.

In case the quotes are making me out to complain about the faults of the NP-101, let me make this very clear: I believe the NP-101 is as near the best 4" APO as one possibly can. To me, it is the best scope out there, based on its flat field (I image), superlative contrast, excellent mechanics in a decently sized body. It does not require additional adapters to convert to visual vs. AP use. The price, used, is a big plus.
I still do think collimation, or the potential need to, is an issue to any prospective owner, especially since I live at the far end of a shipping line, where there is every chance for the scope to be dropped, bumped or crushed under the local zoo's shipment of live elephants (Hyperbole, but you get the idea) but as I've pointed out above, it is easily fixed.


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la200o
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: cloud_cover]
      #5557193 - 12/06/12 10:05 AM

Cloud cover,

I think you should be forgiven, not only for this explanation, but also for the wonderful Google translation you've given us in your previous post.

Clear skies,
Bill


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Sky Muse
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Jon Isaacs]
      #5557292 - 12/06/12 11:11 AM Attachment (10 downloads)

"I also wonder why this thread seems to have transformed into a comparison of the NP-101 and various other doublets."

To illustrate the considerable mechanical advantage of the doublet over a four-element petzval, the latter with the potential of being a collimation nightmare, given the literature attesting to same.

That, begging the question: might one recommend a TeleVue repair shop in Italy in the event a used NP-101 required servicing upon receipt?

"The original poster was interested in the NP-101 vs the TV-102."

"Or", not "vs"...

The gentleman made apparent, "...to see the planets and double stars...", and with said observing interests, the TV-102, a sublime, simpler doublet, would be more than capable, and without the need of an imaging-specific quadruplet coupled with the aforementioned maintenance issues, and all in the interest of ensuring a satisfactorily refractive experience.

"I am wondering how much time you have spent looking through an NP-101? To really know on a scope, it's hard to do without some eyepiece time..."

More's the pity...



Alan


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Sky Muse
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: enniot1]
      #5557396 - 12/06/12 12:04 PM

Hello Ennio,

If you're convinced of the superiority of an FS-102, why not opt for that instead, as they are still available used, with the expense perhaps quite close to that of a TV-102, though probably just as difficult to find, but worth the hunt nonetheless.

The FS-102 is easily collimatable, for a refractor, with its visible and easily-accessible push-pull screws, and over the TeleVues, should the need arise.

To say that I cherish my own...

Cheers,

Alan


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Jim Romanski
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Sky Muse]
      #5557402 - 12/06/12 12:07 PM

Quote:

"Oh, and the corrector permanently chambered, again, photon-absorptive, yet only modestly corrective. Then, we have the literature, opposed to that in favourable appraisal...



"Photon-absorptive" - You mean the additional lenses? You have noticed the miles of atmosphere in front of your objectives I presume. The slight reduction in brightness from the correcting lenses is more than made up for by the overall contrast improvements due to better color focus and optical corrections.

"Literature" - You believe that forum posts constitute literature?

I don't consider jrbarnett's reference to "poor performing NP-101s" to be a definitive sampling of NP101s vs any other scopes. It's just his experience.

How about this literature?

Excerpts from Premium Refractors: Having It All review of Tele Vue NP-101 by Alan Dyer, from May 2002 issue of Sky & Telescope magazine

"Great optics are easy to evaluate — the NP 101 showed no sign of any aberrations, period. End of review! But to elaborate -- under a star test at high power I saw no color, no astigmatism, no spherical aberration, not even any asymmetry in extrafocal patterns from sphero-chromatism. Bright stars appeared as clean, white disks right through focus, with no magenta or cyan fringing inside or outside of focus. In focus, stars appeared as tight, sharp Airy disks, surrounded by a subtle inner diffraction ring and no spurious fuzz — a textbook-perfect pattern."


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KWB
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Re: TELEVUE 102 VS TELEVUE NP101 new [Re: Jim Romanski]
      #5557429 - 12/06/12 12:19 PM

This thread is now locked pending moderator review.

Edit:Folks,this thread has run it's course and it's now time to move on to other subjects.

Edited by KWB (12/06/12 12:47 PM)


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