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Equipment Discussions >> Refractors

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chaoscosmos
sage
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Reged: 01/26/13

Loc: Mission Viejo CA
Best mount / tripod for Televue 85 or NP101
      #5675646 - 02/12/13 11:31 AM

Hey all...

I'm pretty settled on picking up either the TV85 or NP101 Televue scope, mostly for viewing on my patio. The scope will be used just for viewing, not imaging. Which Alt/azimuth mount is most practical and solid for either one of these scopes? Is it the Televue Gibraltor set-up?

Also, is $1600 a reasonable price for a 12 year old TV85? Not sure if it has the same focuser as current models.

Thanks...


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snommisbor
scholastic sledgehammer
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Reged: 06/15/09

Loc: Cedar Park, TX
Re: Best mount / tripod for Televue 85 or NP101 new [Re: chaoscosmos]
      #5675759 - 02/12/13 12:32 PM

For 1600 you could find a TV101. It is the version just before the NP101 and is a great scope. I had one, the focuser isnt that great but I put a FT retro fit on mine and it was awesome. I had the Gibraltar mount as well and it came with the computer I forget what that was called. But it worked great. Used it as a GnG all the time.

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johnnyha
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: snommisbor]
      #5675761 - 02/12/13 12:35 PM

Yeh $1600 is a horrible price, not even close to reasonable. You could find a used FS102 for that price and it will literally wipe the floor with the TV85. And as the previous poster pointed out you can almost get an NP101. DO NOT pay $1600 for that scope there are many better alternatives and I have seen many used TV85s go for around $1K. This is not an APO OK, it does not deserve APO prices.

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PhilCo126
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: johnnyha]
      #5675767 - 02/12/13 12:38 PM

Best mount... plain or GoTo ?

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chaoscosmos
sage
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Reged: 01/26/13

Loc: Mission Viejo CA
Re: Best mount / tripod for Televue 85 or NP101 new [Re: PhilCo126]
      #5675803 - 02/12/13 12:58 PM

Not a GoTo I don't think.

The price is actually $1575, and it comes with a TV Starbeam Sight. But yeah, I think thats' still too high. I'll wait.


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Jon Isaacs
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: chaoscosmos]
      #5675842 - 02/12/13 01:17 PM

Quote:

Not a GoTo I don't think.

The price is actually $1575, and it comes with a TV Starbeam Sight. But yeah, I think thats' still too high. I'll wait.




You could buy an 80mm Lomo Triplet for less than that... A Vixen Portamount class mount should be fine for the 85, marginal even with beefed up legs for the NP-101.

I have a StellarVue MG2 for my NP-101, I have strict requirement for slow-motion controls, it's plenty solid but I prefer the viewing position of the Portamount.

Jon


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FirstSightModerator
Duke of Deneb
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Reged: 12/26/05

Loc: Raleigh, NC
Re: Best mount / tripod for Televue 85 or NP101 new [Re: chaoscosmos]
      #5675864 - 02/12/13 01:28 PM

I'd suggest a Unistar Deluxe (by Universal Astronomics in Massachusetts, a different outfit than CN's host Astronomics out of Oklahoma). Larry (the proprietor) is wonderfully helpful to discuss the best match for your needs. The "deluxe" model has improved clamping/dovetail mechanisms over the vanilla model.

I have an NP-101, and have found that I can get by with the lightweight version of the Unistar Deluxe (which I originally bought for a smaller, lighter WO Megrez 90 refractor and lightweight portability of the mount). However, at 10 lbs the NP-101 is near the rated performance limits of the light version, whereas the regular version of the Unistar is rated for carrying at least 30 lbs, and yet itself weighs only 7 lbs. I'm planning on upgrading to the regular deluxe version this spring.

In addition to the Unistar's high build quality and ease of use, it mounts the scope at an offset to the mount axis on which it attaches to the tripod, which means that you can set the scope to high near-vertical altitudes without the mount itself getting in the way.

As to tripods, the UA lightweight aluminum surveyor's tripod has proved very capable for visual use for the NP-101 (again, I originally got it for the Megrez 90) lighter. However, if I was choosing over with the NP-101 specifically in mind, I'd choose the medium-weight version.


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Jon Isaacs
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: FirstSight]
      #5675940 - 02/12/13 02:11 PM

Quote:

However, at 10 lbs the NP-101 is near the rated performance limits of the light version, whereas the regular version of the Unistar is rated for carrying at least 30 lbs, and yet itself weighs only 7 lbs




When I put my NP-101 on the scales with the diagonal and clamshell, it's about 12lbs if I remember correctly.

Does the Unistar have slow motion controls? I am looking to find a better mount for the NP-101 but it's got to have slow motion controls.

Jon


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t.r.
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: Jon Isaacs]
      #5675953 - 02/12/13 02:24 PM

TV 85's average $1K on Amart as Johnnyha points out!

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Jon Isaacs
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: t.r.]
      #5675975 - 02/12/13 02:40 PM

Quote:

TV 85's average $1K on Amart as Johnnyha points out!




Probably about right for an OTA only, maybe a little low.

Jon


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FirstSightModerator
Duke of Deneb
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Loc: Raleigh, NC
Re: Best mount / tripod for Televue 85 or NP101 new [Re: Jon Isaacs]
      #5675997 - 02/12/13 02:51 PM

Quote:

Quote:

However, at 10 lbs the NP-101 is near the rated performance limits of the light version, whereas the regular version of the Unistar is rated for carrying at least 30 lbs, and yet itself weighs only 7 lbs




When I put my NP-101 on the scales with the diagonal and clamshell, it's about 12lbs if I remember correctly.

Does the Unistar have slow motion controls? I am looking to find a better mount for the NP-101 but it's got to have slow motion controls.

Jon




No, they ordinarily don't, and I don't see that as an optional upgrade accessory on UA's website. However, I would call Larry (UA's principal) at their listed phone # and check whether this might be available or not. You can, however optionally have your mount equipped with encoders for at least push-to DSCs.


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russell23
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: chaoscosmos]
      #5676020 - 02/12/13 02:59 PM

Quote:

Hey all...

I'm pretty settled on picking up either the TV85 or NP101 Televue scope, mostly for viewing on my patio. The scope will be used just for viewing, not imaging. Which Alt/azimuth mount is most practical and solid for either one of these scopes? Is it the Televue Gibraltor set-up?

Also, is $1600 a reasonable price for a 12 year old TV85? Not sure if it has the same focuser as current models.

Thanks...




I have a Vixen 140mm Neo-achro refractor mounted on a Vixen SuperPolaris mount set into alt-azimuth mode. There is an article that shows how you can do this. It is really easy and someone such as myself that lacks mechanical skills can do it very quickly. The Vixen superpolaris mount set up this way should be extremely stable for a scope of the size you are considering. The 140NA pushes it a bit, but with vibration pads it is not bad.

So another option would be to find a used Superpolaris mount. They are really rugged.

Dave


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

Loc: Torrance, CA.
Re: Best mount / tripod for Televue 85 or NP101 new [Re: johnnyha]
      #5676271 - 02/12/13 04:52 PM

Quote:

This is not an APO OK, it does not deserve APO prices.




Actually, the TV85 does have apochromatic performance and uses the best fluorite substitute and matching glass currently available.


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Erik Bakker
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: John Rhodes]
      #5676440 - 02/12/13 07:03 PM

Quote:

Quote:

This is not an APO OK, it does not deserve APO prices.




Actually, the TV85 does have apochromatic performance and uses the best fluorite substitute and matching glass currently available.




Hi John,

Is that a new/improved formulation for the TV85 optics?


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coopman
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Loc: South Louisiana
Re: Best mount / tripod for Televue 85 or NP101 new [Re: Erik Bakker]
      #5676507 - 02/12/13 08:01 PM

The Unistar Deluxe is a very good alt-az mount, but it does not have slo-mo controls.

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Stephen S
professor emeritus
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: coopman]
      #5676559 - 02/12/13 08:40 PM

Quote:

The Unistar Deluxe is a very good alt-az mount, but it does not have slo-mo controls.




+1. Great mount for my NP101. Had it set up with a binoviewer last night. Worked like a charm. Very smooth but no slow motion controls. I have a TV SkyTour connected to mine. Works well at the zenith. Not always the case with all mounts. Sleek, simple and reasonably priced.


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KerryR
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: Stephen S]
      #5676770 - 02/12/13 11:09 PM

I have a Megrez 90, and had a Televue Genesis. I had great success mounting either on a Bogen heavy duty camera tripod with a crank elevator, with a PortaII head. The PortaII's slow motion controls are useful, as is the crank elevator-- the ep is easy to place exactly at a comfortable height. Well executed crank elevators are the next best thing to ball-mounts (Think Astroscan).

I also have a Unistar on a heavy duty wooden surveyor tripod. The motions are smooth enough that I don't miss slow motion controls.

Additionally, I have a Tech2000 pier and a GiroII head. This is a sleek setup, but, for smoothest motions, needs a counterweight. I prefer the un-counterweighted mounts mentioned above.


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John Rhodes
Vendor (Televue Rep)
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: Erik Bakker]
      #5676977 - 02/13/13 02:53 AM

Quote:

Quote:

Quote:

This is not an APO OK, it does not deserve APO prices.




Actually, the TV85 does have apochromatic performance and uses the best fluorite substitute and matching glass currently available.




Hi John,

Is that a new/improved formulation for the TV85 optics?




As far as I know this has always been the design.


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Jon Isaacs
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: John Rhodes]
      #5677080 - 02/13/13 06:39 AM

Quote:

Quote:

This is not an APO OK, it does not deserve APO prices.




Actually, the TV85 does have apochromatic performance and uses the best fluorite substitute and matching glass currently available.




Historically, the TV-85 has always been considered an apochromat. Not all apochroamts are created equally. Roland Christen can probably find signs of chromatic aberration in any refractor...

Among the rest of us, it varies.

Jon


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Jon Isaacs
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: Stephen S]
      #5677094 - 02/13/13 06:52 AM

Quote:

Quote:

The Unistar Deluxe is a very good alt-az mount, but it does not have slo-mo controls.




+1. Great mount for my NP101. Had it set up with a binoviewer last night. Worked like a charm. Very smooth but no slow motion controls. I have a TV SkyTour connected to mine. Works well at the zenith. Not always the case with all mounts. Sleek, simple and reasonably priced.




For short scopes, I really like slow-motion controls. It's about leverage and mechanical advantage. With an NP-101, I have a lever about a foot long. Tracking at 200x-300x is doable but not so easy.

In comparison, a Dobsonian has a long lever which means for a given angular motion, you move it much more which means you have finer control. I figured this out one night when a friend of a friend came over. He had never looked through a telescope, probably never seen one, and yet with in minutes was tracking the 25 inch Obsession at 400x, I couldn't believe it.

But then I realized that the 10 foot long OTA with it's super smooth motions makes a very long lever, the lever is about 8 feet long... That's a factor of about 8 over a short refractor. Tracking at 400x with that scope is not quite like tracking a refractor at 50x but it is surprisingly close.

Jon


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Randal
journeyman
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: chaoscosmos]
      #5677110 - 02/13/13 07:11 AM

My 2 cents-

1. Consider the Quarter Hitch mount currently on A-Mart for $450.
2. Search for a 6-7 year old TV85 pkg for <$1,200.
3. Place scope and mount on good quality photo tripod.
4. Enjoy viewing from your patio.

Since I'm spending your money, don't forget the Nagler 3-6mm, Nagler 9 or 13mm, and Panoptic 35mm eyepieces.

I currently use a variation of this simple setup, and am very happy with it.

My 3rd cent-
Regarding TV scopes - I offer an automotive analogy.
I have a friend that owns a really nice Lexus.
He always boasts to his friends that it's almost a Mercedes.

There is more than specifications at play in this hobby.


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BCNGreyCat
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: chaoscosmos]
      #5677266 - 02/13/13 09:12 AM

My 2 cent. Here is my setup:

TV-85, diagonal, Nagler 16mm, 3-6 zoom
Takahashi Teegul Alt-Az mount
DM-4 wood tripod

The Teegul has slow motion controls. And the DM-4 tripod is rock solid. You can go upto 200x and the damp time is below 1sec on my deck.

My TV102 works on this mount tripod combo as well. NP101 probably is okay. (Teegul probably can handle 15lb OTA)

Only issue, the tripod is not height adjustable and not easily foldable. So transporting from my living room to my deck is a little bit clumsy. But the height of the tripod matches my height (5'9). So not height adjustable is not a big issue to me.

Sometimes, I use an Induro AT-413 photo tripod. Damping on this one is not so well under high power. But if on solid ground, it still acceptable. The AT-413 is light, foldable, height adjustable, yet sturdy enough for quick G-n-G.


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la200o
Carpal Tunnel


Reged: 09/09/08

Loc: SE Michigan, USA
Re: Best mount / tripod for Televue 85 or NP101 new [Re: John Rhodes]
      #5677354 - 02/13/13 10:16 AM

Quote:

Quote:

This is not an APO OK, it does not deserve APO prices.




Actually, the TV85 does have apochromatic performance and uses the best fluorite substitute and matching glass currently available.




+1

The TV doublets are as "apo" as any doublets out there. But $1600 is waaaay too much!

Bill

Edited by la200o (02/13/13 10:20 AM)


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Eddgie
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: chaoscosmos]
      #5677590 - 02/13/13 12:21 PM

Quote:

I'll wait.






Right call. Too much for the scope in question.

As for the mount when the time comes, I personally found the Gibrater to be the least enjoyable mount I have ever used. It will have its defenders, but I found the nose dive risk to be a huge frustration. Just about every eyeppeice change meant having to fuss with the altitude friction, and going from a heavy eyepiece to a light one and forgetting to tighten the tension on the altitude setting can cause a huge nose dive on the scope.

But if you have your target centerd (Jupiter for esample) and change from a 22mm Nagler T4 to a Nagler zoom, it is almost impossible to keep the target in the field unless you tighten the friction locks, but the you have to loosen them to make fine adjustments, then rememeber to tighten them, then remember to loosen them, then remeber to tighten them..................

I used it three times. Tried tried tired to love love love it for simplicty and beauty, but as a working mount for anything but fixed low power sweepting, found it miserable.

Just me though. I prefer a light gear driving Alt-Az. It eliinates the fussing with balance during eyepeice changes.

You only really need it in altitude, but some of the mounts now come with slow motion in both axises.

Good luck whith your search.


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Jon Isaacs
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: Eddgie]
      #5677638 - 02/13/13 12:52 PM

Quote:


Just me though. I prefer a light gear driving Alt-Az. It eliinates the fussing with balance during eyepeice changes.






An added note:

For about 2 years, I used my NP-101 with a Portamount with the HandsonOptics wooden legs. I really like everything about that mount except that it is on the small side and I had switched to another mount which is solid, has all the features but I just don't like it.

This morning I was looking at the Portamount and realized that the azimuth axis had some slop. I dismounted the mount, adjusted the center bolt tension (actually a nut), reassembled it and gave it a try. My Portamount is back to it's old self, I am enjoying the NP-101 again and I will probably find a new home for the other mount.

Jon


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FirstSightModerator
Duke of Deneb
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Loc: Raleigh, NC
Re: Best mount / tripod for Televue 85 or NP101 new [Re: Jon Isaacs]
      #5677788 - 02/13/13 02:32 PM

Quote:

Quote:

Quote:

This is not an APO OK, it does not deserve APO prices.




Actually, the TV85 does have apochromatic performance and uses the best fluorite substitute and matching glass currently available.




Historically, the TV-85 has always been considered an apochromat. Not all apochroamts are created equally. Roland Christen can probably find signs of chromatic aberration in any refractor...

Among the rest of us, it varies.

Jon




The reason for the ambiguity about the TV85 being an "apochromat" vs only a "semi-apochromat" (as in, not quite a true full-fledged APO) is because it's a doublet, rather than a triplet or Petzval (four-element) lens design. The argument for considering some of the higher-end doublets to sufficiently qualify for true APO status is because though two lenses still cannot as completely correct refractive differences in where different wavelengths of light focus as can high-quality triplets etc., nevertheless through use of the right glass and lens design it's possible to come close enough that the differences are near-vanishingly small to most people's eyes, or at least supposedly. So, to some extent it's in the eye of the beholder whether a doublet such as the TV-95 is a true apochromat or merely an almost, but not quite true apochromat. Nevertheless, it's not misleading marketing to describe a high-quality doublet like the TV-85 as an "apochromat", so long as the fact that it's a doublet is included in the description.


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Jon Isaacs
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: FirstSight]
      #5677874 - 02/13/13 03:35 PM

Quote:

The reason for the ambiguity about the TV85 being an "apochromat" vs only a "semi-apochromat" (as in, not quite a true full-fledged APO) is because it's a doublet, rather than a triplet or Petzval (four-element) lens design.




I am not sure that is the reason. There are many doublets that have long been considered apos, fir example, the TV-102, the various Takahashi's using fluorite and synthetic fluorite. Roland's article says that a doublet is capable of producing the necessary three color crossings but one is not in the visual.

I think the reason people question the TV-85 as an apo is that at 85mm F/7 with presumably an FPL-53 based objective, it's pushing the limit in terms of being color free visually.

Jon


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FirstSightModerator
Duke of Deneb
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Loc: Raleigh, NC
Re: Best mount / tripod for Televue 85 or NP101 new [Re: Jon Isaacs]
      #5678111 - 02/13/13 06:14 PM

Quote:

Quote:

The reason for the ambiguity about the TV85 being an "apochromat" vs only a "semi-apochromat" (as in, not quite a true full-fledged APO) is because it's a doublet, rather than a triplet or Petzval (four-element) lens design.




I am not sure that is the reason. There are many doublets that have long been considered apos, fir example, the TV-102, the various Takahashi's using fluorite and synthetic fluorite. Roland's article says that a doublet is capable of producing the necessary three color crossings but one is not in the visual.

I think the reason people question the TV-85 as an apo is that at 85mm F/7 with presumably an FPL-53 based objective, it's pushing the limit in terms of being color free visually.

Jon




I'm explaining the reasoning in many folks' minds when they question whether a doublet is a true APO, rather than the authoritative technical answer. I've come across the reference from Roland Christian you cited above.

I still think it's best practice to always be sure that when you refer to a given doublet scope as an "APO" that the audience understands that the scope is a doublet. That way, at worst some folks may regard the assertion as somewhat debatable, but none as misleading - and if applicable to the scope in question, you still have the Roland Christian trump card to pull out in response.


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tomchris
professor emeritus


Reged: 12/22/10

Loc: Connecticut, U.S.A.
Re: Best mount / tripod for Televue 85 or NP101 new [Re: FirstSight]
      #5678157 - 02/13/13 06:43 PM

I use my 85 on a Bogen/ Manfrotto tripod and it works very well. If I really want steadiness, I get out my DM-4 mount and tripod. I found the "apo" debate interesting. All I know is that the TV85 is very sharp and provides wonderful colorful views. However, $1600 is way too much to buy the 85 used!

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Jon Isaacs
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: FirstSight]
      #5678183 - 02/13/13 06:59 PM

Quote:


I'm explaining the reasoning in many folks' minds when they question whether a doublet is a true APO, rather than the authoritative technical answer. I've come across the reference from Roland Christian you cited above.

I still think it's best practice to always be sure that when you refer to a given doublet scope as an "APO" that the audience understands that the scope is a doublet. That way, at worst some folks may regard the assertion as somewhat debatable, but none as misleading - and if applicable to the scope in question, you still have the Roland Christian trump card to pull out in response.





This the way I look at it:

There are doublets that are not apos, there are doublets that are.

There are triplets that are not apos, there are triplets that are.

There are quadruplets that are not apos, there are quadruplets that are.

Generally one should specify whether a scope is a doublet, triplet, quadruplet and some designation of the color correction.

I think Thomas Back's discussion Defining Apochromatismhit's the nail right on the head.

" After designing, testing and selling many different apochromatic lenses I can state this: There is no "definite" line where a lens becomes "apochromatic" in the world of commercial apochromatic lenses.

But any lens, be it a doublet, triplet, quad, air-spaced or Petzval, that has a peak visual null (~5550A - the green-yellow) with a Strehl ratio of .95 or better, coma corrected and is diffraction limited from C (red) to F (blue) with 1/4 wave OPD spherical or better, has good control of the violet g wavelength with no more than 1/2 wave OPD P-V spherical and optical spot sizes that concentrate the maximum amount of photons within the diffraction limit -- a result of the low spherical aberration, which can be seen with modern optical design programs, as the "spot rays" will be seen concentrated in the center of the spot, not evenly or worse, concentrated outside the center -- will satisfy the modern definition of "Apochromatism.""

Jon


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tomchris
professor emeritus


Reged: 12/22/10

Loc: Connecticut, U.S.A.
Re: Best mount / tripod for Televue 85 or NP101 new [Re: Jon Isaacs]
      #5679020 - 02/14/13 09:35 AM

Excellent. Thanks, Jon.

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KerryR
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: tomchris]
      #5679042 - 02/14/13 09:46 AM

I suspect that one of the reasons for the continuing debate about what makes an apo an apo has a lot to do with CCD cameras and their sensitivity to the blue end of the spectrum. A scope that a visual observer finds to have excellent color correction may produce a raw ccd image with heavy blue-end fringing. A "ccd apo" might be considered as having more stringent tolerances than a "visual apo" if the user wishes to avoid some post-process reduction of the fringing.

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Panotaker
sage


Reged: 09/12/03

Loc: Austin, Texas
Re: Best mount / tripod for Televue 85 or NP101 new [Re: KerryR]
      #5679079 - 02/14/13 10:04 AM

I have both a TV-85 and an NP-101. I bought my TV-85 used 10 years ago, so it is a pretty old one. I haven't looked through a late model TV-85 to compare to mine, but my TV-85 gives perfect color free views, that is the main reason I bought it. I have a Gibraltar V mount that I mount all kinds of scopes on, from my Questar Birder, to my AP-130. It doesn't have slow motion controls, but unless you are looking at the planets, you don't really need them. I have the digital setting circles on mine and they work excellent. There are better alt/az mounts out there, but I got mine pretty cheap, so I'm not upgrading any time soon. The nice thing about the mount, is that it looks fantastic, so you can leave it setup inside the house and it looks like a piece of furniture. You can't say that about most mounts.

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la200o
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: Panotaker]
      #5679333 - 02/14/13 12:16 PM

I had my (f/6.3) TV 76 out last night and was once again impressed at how color-free it is. It is an APO.

I have it over-mounted on a Gibraltar, which I retired for awhile a few years ago after buying a Half-Hitch. When I got the TV 76, I brought the mount out of retirement and use it constantly with that scope and now and then with my 4" TV's. I have come to appreciate its virtues. Simple, steady, and, with proper adjustments, pretty smooth. You can pick them up inexpensively used (300--400 bucks and they are well worth the money IMO).

Bill

Edited by la200o (02/14/13 02:55 PM)


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KerryR
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: la200o]
      #5679356 - 02/14/13 12:26 PM

I have a TV Telepod head that I used with my Pronto and Genesis. I believe it's the same as the Gibralter.(?)

Functional enough, but I prefer the PortaII head-- far easier to maintain position while switching ep's, and, of course, the slow motion controls add additional ease when tracking.

I now only use the Telepod with my PST.


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la200o
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: KerryR]
      #5679365 - 02/14/13 12:31 PM

Kerry, I've never used a PortaII; I believe what you say. For me, changing ep's w/the Gibraltar ain't so bad--a finger on the diagonal pretty much keeps the scope in place, and if it does move, it's generally strictly in the altitude axis, so it's pretty easy to recover the target. Now changing ep's with my HH--that's another story!

Bill


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Patrik Iver
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: John Rhodes]
      #5679677 - 02/14/13 02:52 PM

Quote:

Actually, the TV85 does have apochromatic performance and uses the best fluorite substitute and matching glass currently available.




This is the first time I've seen someone "in the know" imply anything about the glass prescription of a TV doublet. So effectively you are saying that the ED-glass used is Ohara FPL53, as it can't very well be a Russian glass with similar properties?

Why the big secrecy about it? The scopes are doublets, and sold as such. Specifying the glass prescription (particularly if it is "the best fluorite substitute and matching glass currently available") should not be a bad thing? Just about anyone agrees anyway that your telescopes are very nice, both optically and mechanically.


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la200o
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: Patrik Iver]
      #5679689 - 02/14/13 02:57 PM

Patrik,

I agree. I think the TV scopes are great, and I imagine they use FPL53. So why not tell us?

Bill


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johnnyha
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: la200o]
      #5679721 - 02/14/13 03:15 PM

Quote:

This is not an APO OK, it does not deserve APO prices.



OK OK, I officially withdraw my original post implying that the TV85 was not an APO.


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Jon Isaacs
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: la200o]
      #5679915 - 02/14/13 05:20 PM

Quote:

Patrik,

I agree. I think the TV scopes are great, and I imagine they use FPL53. So why not tell us?

Bill




I think the "what glass is it" game started quite some time after TeleVue began making refractors. Many vendors play this game by telling you when they do use FPL-53 but choose more vague descriptions when they use something with a significantly lower Abbe index.

TeleVue may be somewhat unique in that they don't broadcast exactly which glasses they use but then they are unique in a number of ways.

One aspect that is interesting is that Roland C. is well known for pointing out that it's not only the ED glass used but also the mating element. I am as guilty as anyone else of referring to the ED glass only.

I would like to know what glasses the NP-101 uses, that the focal ratio of the objective is... Don't think I will be finding out.

Jon


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la200o
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: Jon Isaacs]
      #5679982 - 02/14/13 06:10 PM

Jon,

Alas, I fear you are right. We will never unravel this mystery.

Regards,
Bill


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Jon Isaacs
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: la200o]
      #5680046 - 02/14/13 06:46 PM

Quote:

Jon,

Alas, I fear you are right. We will never unravel this mystery.

Regards,
Bill




Bill:

If I knew, it wouldn't affect the views one iota nor would I actually understand anything more.

Jon


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FirstSightModerator
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: la200o]
      #5680304 - 02/14/13 10:08 PM

Quote:

Patrik,

I agree. I think the TV scopes are great, and I imagine they use FPL53. So why not tell us?

Bill




Televue is perfectly willing to patiently tell you what you know, in as much detail as you want to know, while the cement block slowly hardens around your legs, out by a boat-dock on a very deep lake.



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Keith-in-Texas
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: FirstSight]
      #5682380 - 02/15/13 09:21 PM

Here's what I did when looking for a lightweight yet sturdy and high quality mount for my Stellarvue SV90TBV.

I purchase a "like new" Vixen Super Polaris mount (non go-to) with excellent slow motion controls. This mount can be use in either GEM or Alt-Az configuration.

Best thing is they can be picked up used for $150 - $250 depending on condition and options.

Good luck in your search for the optimum mount that meets your needs.

Best regards,

Keith


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John Rhodes
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: KerryR]
      #5682623 - 02/15/13 11:57 PM

Quote:

I have a TV Telepod head that I used with my Pronto and Genesis. I believe it's the same as the Gibralter.(?)




They are the same head for all the tripods Tele Pod, Panoramic and the Gibraltar, only the Gibraltar 5 is different being wide enough to hold the 127is scope.


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chaoscosmos
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: John Rhodes]
      #5698315 - 02/24/13 01:55 PM

"I used it three times. Tried tried tired to love love love it for simplicty and beauty, but as a working mount for anything but fixed low power sweepting, found it miserable."

Well, as some may know, I was able to pick up a used NP-101 and at the same time was convinced on a used Gibraltor mount and tripod. At this point, unless I'm just not handling it correctly, I'm having the same reaction to the Gibraltar mount as Eddgie did in his quote above. I've used it on three successive nights, rebalanced the OTA a couple of times, and still find it a pain to use at even moderately high magnification. Has a serious case of the jiggles focusing at even 60X and damping time seems too long. I could add a Feather Touch focuser, which should help focusing some. The tripod seems rock solid, I just think it's the mount that's lacking. Mine says 'Gibraltar', not 'Gibraltar 5' ~ not sure if there's a difference. But in any case, I'm looking at Discmount and wondering if I'm going to be sinking into a money pit here, especially since I don't know if another mount would be worthwhile either.

I know that suspending a 10 lb tube in space and expecting it to be rock solid and yet easily moveable is a formidable task, but I expected a $4K set-up to have none of the weak characteristics of my 60mm Sears refractor alt/azimuth mount I had as a kid. Although it's 500% better, to my surprise, there are still some similarities.

Edited by chaoscosmos (02/24/13 02:01 PM)


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Mark9473
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: chaoscosmos]
      #5698513 - 02/24/13 04:10 PM

Quote:

I know that suspending a 10 lb tube in space and expecting it to be rock solid and yet easily moveable is a formidable task



Not for a DiscMount.


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chaoscosmos
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: Mark9473]
      #5699314 - 02/25/13 05:15 AM

Oh my, I'm a little embarrassed now. The Gibraltar seemed so bad I began thinking something must be broken on it, and in effect, it was. I took the OTA off to get a good look at the mount and within a few seconds realized the plastic tighten down nut underneath the center of the tripod wasn't tightened. Since this was a used mount and tripod, everything was already put together and I assumed it was all good to go. Now it is and I'll be able to get a reasonable idea of how much I like the mount. One thing is clear- the jiggling has almost completely disappeared, so the scope stops dead when you want it to stop. What a relief.

Sorry Televue, my fault, operator error was the culprit!


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Jim7728
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Re: Best mount / tripod for Televue 85 or NP101 new [Re: chaoscosmos]
      #5699390 - 02/25/13 08:01 AM

I used Genesis SDF(old NP-101) on a Telepod with an Oberwerk wooden tripod and thought the setup worked fine. I did have a Focusmate fine focus attached to the R&P, which is a must have for such a fast telescope. Also some dampening pads for the tripod legs which are effective when viewing at high magnification.

One other accessory nice to have is the Televue Equalizer Brass 1.25" to 2" adapter which eliminates the need to re-balance when going from a heavy 2" eyepiece to a light 1.25".


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