Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Dobsian pricing

  • Please log in to reply
62 replies to this topic

#1 Xxray

Xxray

    Vostok 1

  • -----
  • topic starter
  • Posts: 100
  • Joined: 23 Feb 2014

Posted 18 January 2020 - 10:59 PM

Am considering a dob come this spring, am likely going to go with a goto collapsible design. Not much to chose from with those specifics, Skywatcher series is about it.

 

As of this writing, a 8" costs $913, a 10" $1,135. 12" will set you back $2,105, a 14" $2,555 and a 16 $3,400.

 

So a 2 inch jump from 8 to 10 is an even $222. A 2 inch jump from 10" to 12", on the other hand,  is $970, hmmmm. So have we established that slightly larger dobs are insanely more expensive than the next lower model ? Not really, for a 2" jump from 12" to 14" is just $450. But eegads, a 2" jump from 14" to 16" is $845.

 

I assume there is some logical production reason why pricing is so illogical and all over the place, anyone care to take a guess ? I am likely going to go with the 10" but am curious why it would cost an extra $970 to go from a 10 to a 12 but only $222 to go from an 8 to a 10.



#2 Tdesert63

Tdesert63

    Vostok 1

  • *****
  • Posts: 103
  • Joined: 10 Nov 2016

Posted 18 January 2020 - 11:20 PM

Keep a eye on Orion's clearance center, picked up a xx12g 500.00 off, enough for shroud, field battery, and travel bags,all in one shot, loving it
  • Barlowbill likes this

#3 ShaulaB

ShaulaB

    Surveyor 1

  • *****
  • Posts: 1,731
  • Joined: 11 Oct 2012
  • Loc: Missouri

Posted 18 January 2020 - 11:22 PM

If you can do without the Go To electronics, you can cut the price about in half. (Ducking, as no doubt a brick will be tossed at my head.)

 

Perhaps the difference in weight going from 10" to 12" means more beefy and reliable slewing/tracking motors are needed, plus higher quality plywood for the base and rocker. Perhaps more expensive, more complex encoders or steppers might be needed?

 

Perhaps peer pressure? When I was fairly new at this, my 10" Dob was considered huge. Nowadays, the conventional wisdom seems to be one needs at least 12 inches of aperture to successfully view deep sky objects. Eight and ten inch Dobs seem to be considered baby stuff by some. Not me; if I were running for President, I would run on a platform of an 8" Dob in every house.


  • Jon Isaacs, Bean614, 25585 and 3 others like this

#4 Xxray

Xxray

    Vostok 1

  • -----
  • topic starter
  • Posts: 100
  • Joined: 23 Feb 2014

Posted 18 January 2020 - 11:35 PM

No I want goto, not manual. I would consider a 12" but am doubting it would be worth the large $1K premium over a 10", vs all the nice lenses/filters I could get with the same $1K. Am trying my level best to avoid size fixation here.

 

Tdesert63, where might orions clearance center be located ? FAIK, they don't make collapsible goto dob telescopes, and that is what I want.



#5 mitchellcloud

mitchellcloud

    Sputnik

  • *****
  • Posts: 26
  • Joined: 12 Jan 2016
  • Loc: Kansas City, KS

Posted 18 January 2020 - 11:48 PM

I see 10" and 12" dobsonians (truss and tube) come up on Craigslist and Fbook Marketplace pretty frequently. Those can be great ways of getting a scope for a much lower cost. Also sometimes you can talk people down depending on how much they want get rid of it. If you have time and patience you can get a pretty good deal. I got my 12" Orion Intelliscope for $600 from an older gentleman that I still talk with and visit occasionally - he couldn't move it anymore, but he still likes talking astronomy with someone. He was happy to sell it and trade for a little company I think.


  • Lenard, stubeeef and Barlowbill like this

#6 Barlowbill

Barlowbill

    Viking 1

  • *****
  • Posts: 642
  • Joined: 05 Apr 2018
  • Loc: Tulsa, Oklahoma

Posted 18 January 2020 - 11:50 PM

I know less than about anyone on CN.  I have an 8".  I wish I had a 12" that weighted as much as a 6".  I just turned 70 years old.  Happy Birthday to me!  I don't really think you can rationalize prices.  Companies have to take a lot of expenses into consideration when pricing.  I don't think pricing of most items is over the top because of competition.  It may not make sense but it is what it is and we must live with it.  I hope you get a real big Dob and enjoy it forever.  Peace! 


  • 25585 and Jdrasberry like this

#7 Xxray

Xxray

    Vostok 1

  • -----
  • topic starter
  • Posts: 100
  • Joined: 23 Feb 2014

Posted 19 January 2020 - 12:07 AM

I know less than about anyone on CN.  I have an 8".  I wish I had a 12" that weighted as much as a 6".  I just turned 70 years old.  Happy Birthday to me!  I don't really think you can rationalize prices.  Companies have to take a lot of expenses into consideration when pricing.  I don't think pricing of most items is over the top because of competition.  It may not make sense but it is what it is and we must live with it.  I hope you get a real big Dob and enjoy it forever.  Peace! 

I may give you some competition in the know less dept ! Was just curious over the random price differences between sizes, with one 2" jump being 300% more than another - Hard to avoid the conclusion that they do it just because they can. More than likely, the jack up the prices on their best selling models is all I can think of. In any case, I'll get the biggest i can afford and transport and take it from there, I'm not going to bellyache about prices.



#8 Eddgie

Eddgie

    ISS

  • *****
  • Posts: 25,605
  • Joined: 01 Feb 2006

Posted 19 January 2020 - 12:25 AM

While some of it is marketing, a lot of the price difference is in the amount of glass that has to be ground.

Remember, a 2 inch increase in aperture is not just 2" in aperture, it is a big jump in surface area and if you pay attention, as the dobs get bigger, the focal ratio gets faster so not only is there a much bigger area which requires more glass to be ground, but the faster speed means that the curves have to be deeper, and well, that means even more glass that has to be ground and polished, and the raw amount of material that has to be ground away gets pretty huge.

 

(Figures..  An 8" f/6 has about 50 square inches of surface area, where a 10" has about 78 square inches of surface area, so it really isn't just 2 inches... It is a 156% increase in surface area an that surface has to be ground deeper in the 10" than in the 8" because the curves are f/5 vs f/6.  That does not sound like much, but it is a lot of extra grinding.) 

 

So, you go from 8" with an f/6 curve to a 10" with a steeper f/5 curve, then to 12" with an f/4.9 curve, then to 14" with an f/4.5 curve and well, as you can see, you have to grind far more glass away.  Again it is area and the depth of the curves that make bigger mirrors so much more expensive.

See, the machine can make one mirror at a time.   Now if I make one big mirror and I have to grind 10 times as much material away, that means I have to have that machine tied up for far longer, and that means I cannot make as many mirrors, and I am still paying the same amount for my manufacturing facility, my workers, my marketing people, my insurance, my sales people...  Get it?   So, If it takes a lot longer to make one scope, I have to get as much profit out of it as I would get out of four smaller scopes.  

 

 

The sheet metal in one of these dobs costs few bucks, and the entire production cost of the truss tube is probably $50.   It is the mirror where the production cost is, and a big mirror takes a whole lot of grinding
 

Area to be ground and the steepness of the curves.  

 

Make sense?


Edited by Eddgie, 19 January 2020 - 08:36 AM.

  • opticsguy, ewave, kevint1 and 5 others like this

#9 JohnBear

JohnBear

    Vostok 1

  • *****
  • Posts: 110
  • Joined: 08 Jul 2017
  • Loc: Sandy, Utah

Posted 19 January 2020 - 12:39 AM

I'm turning 79 in a few weeks, so opted for the 8" collapsible Dob (rather that the 10") for overall convenience and usability. No regrets! Your Best Scope is the one you use..I didn't want the Intelli/Goto versions since I'm a BIY'r and I prefer to make and use manual setting circles for Push-to operation. I have other scopes on SLT and SE mounts when I want Goto and tracking. I just find manually observing with a Dob to be "quite satisfying".  

 

I got the 8" Dob new last summer during Amazon's Prime Days sale at a good discount price, plus I signed up for the Prime Card (for 2 months) and got $70 off, with 5% for buying on the Prime card. The actual price paid for the new Dob was ridiculously affordable. With the money I saved, I was also able to purchase several very nice used Stratus eyepieces to use with it. The wait for Prime Day was well worth it! 

 

In collapsed form my 8" Dob is quite manageable and fits nicely in my car when I want haul it to my local semi-dark spot. I found a $10 used collapsible golf bag cart that the OTA fits perfectly in for moving it around to and from the car, but most of the time it is on a pull-handle dolly in the garage for quick trips out to the driveway for quick evening planetary viewing sessions. 


  • Jon Isaacs likes this

#10 Xxray

Xxray

    Vostok 1

  • -----
  • topic starter
  • Posts: 100
  • Joined: 23 Feb 2014

Posted 19 January 2020 - 12:52 AM

While some of it is marketing, a lot of the price difference is in the amount of glass that has to be ground.

Remember, a 2 inch increase in aperture is not just 2" in aperture, it is a big jump in surface area and if you pay attention, as the dobs get bigger, the focal ratio gets faster so not only is there a much bigger area which requires more glass to be ground, but the faster speed means that the curves have to be deeper, and well, that means even more glass that has to be ground and polished, and the raw amount of material that has to be ground away gets pretty huge.

 

(Figures..  An 8" f/6 has about 50 square inches of surface area, where a 10" has about 78 square inches of surface area, so it really isn't just 2 inches... It is a 156% increase in surface area an that surface has to be ground deeper in the 10" than in the 8" because the curves are f/5 vs f/6.  That does not sound like much, but it is a lot of extra grinding. 

 

So, you go from 8" with an f/6 curve to a 10" with a steeper f/5 curve, then to 12" with an f/4.9 curve, then to 14" with an f/4.5 curve and well, as you can see, you have to grind far more glass away.  Again it is area and the depth of the curves that make bigger mirrors so much more expensive.

See, the machine can make one mirror at a time.   Now if I make one big mirror and I have to grind 10 times as much material away, that means I have to have that machine tied up for far longer, and that means I cannot make as many mirrors, and I am still paying the same amount for my manufacturing facility, my workers, my marketing people, my insurance, my sales people...  Get it?   So, If it takes a lot longer to make one scope, I have to get as much profit out of it as I would get out of four smaller scopes.  

 

 

The sheet metal in one of these dobs costs few bucks, and the entire production cost of the truss tube is probably $50.   It is the mirror where the production cost is, and a big mirror takes a whole lot of grinding
 

Area to be ground and the steepness of the curves.  

 

Make sense?

Sense, yes and no. Yes, the value and cost is in precision components - And I [of course] expect to pay more for something bigger requiring more time to fabricate. It would make perfect sense if the increase was consistent with graduating sizes but they aren't,  they are all over the place. Note, I was not comparing prices of the scopes per se in the OP but rather the price differences between sizes.



#11 macdonjh

macdonjh

    Aurora

  • *****
  • Posts: 4,943
  • Joined: 06 Mar 2006

Posted 19 January 2020 - 07:57 AM

While some of it is marketing, a lot of the price difference is in the amount of glass that has to be ground.

Remember, a 2 inch increase in aperture is not just 2" in aperture, it is a big jump in surface area and if you pay attention, as the dobs get bigger, the focal ratio gets faster so not only is there a much bigger area which requires more glass to be ground, but the faster speed means that the curves have to be deeper, and well, that means even more glass that has to be ground and polished, and the raw amount of material that has to be ground away gets pretty huge.

 

(Figures..  An 8" f/6 has about 50 square inches of surface area, where a 10" has about 78 square inches of surface area, so it really isn't just 2 inches... It is a 156% increase in surface area an that surface has to be ground deeper in the 10" than in the 8" because the curves are f/5 vs f/6.  That does not sound like much, but it is a lot of extra grinding. 

 

So, you go from 8" with an f/6 curve to a 10" with a steeper f/5 curve, then to 12" with an f/4.9 curve, then to 14" with an f/4.5 curve and well, as you can see, you have to grind far more glass away.  Again it is area and the depth of the curves that make bigger mirrors so much more expensive.

See, the machine can make one mirror at a time.   Now if I make one big mirror and I have to grind 10 times as much material away, that means I have to have that machine tied up for far longer, and that means I cannot make as many mirrors, and I am still paying the same amount for my manufacturing facility, my workers, my marketing people, my insurance, my sales people...  Get it?   So, If it takes a lot longer to make one scope, I have to get as much profit out of it as I would get out of four smaller scopes.  

 

 

The sheet metal in one of these dobs costs few bucks, and the entire production cost of the truss tube is probably $50.   It is the mirror where the production cost is, and a big mirror takes a whole lot of grinding
 

Area to be ground and the steepness of the curves.  

 

Make sense?

 

 

Sense, yes and no. Yes, the value and cost is in precision components - And I [of course] expect to pay more for something bigger requiring more time to fabricate. It would make perfect sense if the increase was consistent with graduating sizes but they aren't,  they are all over the place. Note, I was not comparing prices of the scopes per se in the OP but rather the price differences between sizes.

In addition to what Eddgie said, also consider the structure to support the larger mirror.  That also gets bigger, heavier and more time consuming to make.  Shipping costs also increase with increasing weight and bulk.  In other discussions on this topic I somebody suggested it was more reasonable to increase the price of a telescope by the the cube of the objective's diameter rather than a linear relationship.  In other words, rather than comparing the price relationship between bigger and bigger scopes based on the diameter of the objective, compare prices based on the volume of the whole telescope.

 

The same it true of the secondary mirror.  When you get into big scopes, the secondary mirror gets to be as big as the primary mirror in the scopes us normal people have.

 

Here's something to consider: I have a 14" classical Cassegrain in my observatory.  It weighs fifty-five pounds, plus or minus.  A friend just bought a 20" Ritchey- Cretien for his observatory.  Approximately 50% increase in diameter of the objective, but his scope weighs 200 pounds.  A quick estimation of the volume of the telescopes (my 14" as a wild guess is 6500 in3, his 20", 18850 in3).  So, it's not quite diameter cubed, but it sure isn't a 50% increase in weight or volume, either.  I can see how costs rise so quickly as scopes get bigger: 50% bigger diameter, but triple the volume and quadruple the weight.  More materials, more fabrication time, more shipping cost.  And bigger and more costly tools to bring it all together, too.



#12 Eddgie

Eddgie

    ISS

  • *****
  • Posts: 25,605
  • Joined: 01 Feb 2006

Posted 19 January 2020 - 08:46 AM

Sense, yes and no. Yes, the value and cost is in precision components - And I [of course] expect to pay more for something bigger requiring more time to fabricate. It would make perfect sense if the increase was consistent with graduating sizes but they aren't,  they are all over the place. Note, I was not comparing prices of the scopes per se in the OP but rather the price differences between sizes.

As I said, some of that is marketing.   I might have a more popular size and if it is a more popular size, I can charge more for it, or I might have a model that is selling too slow and taking up too much capital and warehouse space.

 

Also, is a Lexus really worth $10,000 more than the similar sized Toyota? Well, yes, yes it is because people think it is worth more. It takes almost exactly the same amount of time to make the Lexus and while the engines might be slightly different, it takes almost exactly the same number of machining operations and material to make the engines used in each car. 

 

And what about competition from BMW?  Maybe they have a model that is comparable to mine and I want to improve sales of my model. Maybe I spend more money advertising it, and that cost generally goes against the product managers budget.

 

And that was why the very first thing I said was "While some of it is marketing". 

 

There is a whole lot to marketing that most people don't really consider.

 

To us, this is a hobby, but to the people that build telescopes it is a business and the goal of any business is to make as much as possible from the consumer.   Marketing is ultimately what sets prices.



#13 Jon Isaacs

Jon Isaacs

    ISS

  • *****
  • Posts: 81,843
  • Joined: 16 Jun 2004
  • Loc: San Diego and Boulevard, CA

Posted 19 January 2020 - 08:47 AM

Sense, yes and no. Yes, the value and cost is in precision components - And I [of course] expect to pay more for something bigger requiring more time to fabricate. It would make perfect sense if the increase was consistent with graduating sizes but they aren't,  they are all over the place. Note, I was not comparing prices of the scopes per se in the OP but rather the price differences between sizes.

 

I don't buy the difference being in the optics or scope structure.  The difference between a manual 10 inch Dob and a manual 12 inch Dob is about $300. 

 

I am looking at the difference between the Orion 10 inch GOTO tube Dob and the Orion 12 inch GOTO truss Dob, the biggest difference is in the weight of the mount. The 10 inch weighs 38.5lbs, the 12 inch weighs 79lbs.  The 12 inch Skywatcher base weighs the same 79 pounds.  There has to more than just particle board.. 

 

I am not a GOTO guy, my 16 inch is about 35 pounds lighter than the 12 inch SkyWatcher GOTO.  

 

Jon



#14 Jon Isaacs

Jon Isaacs

    ISS

  • *****
  • Posts: 81,843
  • Joined: 16 Jun 2004
  • Loc: San Diego and Boulevard, CA

Posted 19 January 2020 - 08:51 AM

Also, is a Lexus really worth $10,000 more than the similar sized Toyota? Well, yes, yes it is because people think it is worth more. It takes almost exactly the same amount of time to make the Lexus and while the engines might be slightly different, it takes almost exactly the same number of machining operations and material to make the engines used in each car.

 

 

Toyota's have very high standards for their parts suppliers. The standards for Lexus's is even higher.  If you know about machining, then you know that precision costs money, finish quality costs money.  Cutting speeds are reduced, cuts are smaller, more measurements taken.  It's very much like a mirror, you want an Orion mirror or you want a Lockwood mirror.  

 

Jon


  • Jdrasberry likes this

#15 skyward_eyes

skyward_eyes

    Vendor - Sky-Watcher USA

  • *****
  • Vendors
  • Posts: 5,087
  • Joined: 12 Dec 2006

Posted 19 January 2020 - 08:52 AM

The 12” is more expensive for a couple reasons.

1) The mirror is larger and also thicker so more glass to produce a 12” then the 10”.

2) The 12” GoTo base has a different clutch system that allows you to manually adjust the clutch tension where the smaller 8 and 10 do not.

3) The gearing on the 12” is larger and more expensive to produce.

4) The base also uses more material to produce than smaller models.

Ultimately it’s up to you on which you choose to go with.
  • Jon Isaacs, Mike Spooner and Mark SW like this

#16 Tdesert63

Tdesert63

    Vostok 1

  • *****
  • Posts: 103
  • Joined: 10 Nov 2016

Posted 19 January 2020 - 09:47 AM

It's on the Orion web page ,and it a truss tube,

#17 Xxray

Xxray

    Vostok 1

  • -----
  • topic starter
  • Posts: 100
  • Joined: 23 Feb 2014

Posted 19 January 2020 - 10:56 AM

People, once again, I am not having a problem understanding why a 10" scope costs more than an 8" scope. I am trying to fathom why some 2" jumps are 3x the cost of others, and its apparently not all about size as you can see referencing the OP.- If it was, the jumps would be consistent. Gearing/clutches/base complexity may be at least a partial explanation.

 

 

I don't buy the difference being in the optics or scope structure.  The difference between a manual 10 inch Dob and a manual 12 inch Dob is about $300. 

 

I am looking at the difference between the Orion 10 inch GOTO tube Dob and the Orion 12 inch GOTO truss Dob, the biggest difference is in the weight of the mount. The 10 inch weighs 38.5lbs, the 12 inch weighs 79lbs.  The 12 inch Skywatcher base weighs the same 79 pounds.  There has to more than just particle board.. 

 

I am not a GOTO guy, my 16 inch is about 35 pounds lighter than the 12 inch SkyWatcher GOTO.  

 

Jon

 

Good point, never thought to compare price jumps manual scope vs goto.
 



#18 vdog

vdog

    Apollo

  • *****
  • Posts: 1,284
  • Joined: 30 Aug 2018
  • Loc: California Central Valley, U.S.A.

Posted 20 January 2020 - 10:58 AM

I've done research on different types of scopes and noticed there always seems to be a critical point where the jumps to the next size up start to become significantly (and sometimes prohibitively) more expensive.  With dobs, as you've noticed, it's the jump from 10 to 12 inches. With other types of scopes, it isn't just the OTA but the mounting requirements that jack up the costs.

 

Bottom line is aperture will cost you.  I would keep an eye on the classifieds.  I've seen some really good deals come up on 12 and 14 inch dobs.  One might pop up near you.


Edited by vdog, 20 January 2020 - 10:58 AM.


#19 Xxray

Xxray

    Vostok 1

  • -----
  • topic starter
  • Posts: 100
  • Joined: 23 Feb 2014

Posted 20 January 2020 - 12:15 PM

I've done research on different types of scopes and noticed there always seems to be a critical point where the jumps to the next size up start to become significantly (and sometimes prohibitively) more expensive.  With dobs, as you've noticed, it's the jump from 10 to 12 inches. With other types of scopes, it isn't just the OTA but the mounting requirements that jack up the costs.

 

Bottom line is aperture will cost you.  I would keep an eye on the classifieds.  I've seen some really good deals come up on 12 and 14 inch dobs.  One might pop up near you.

 

Only with goto dobs though, 10 to 12 jump in manual is $340 vs $970 for gotos.  Mounting indeed likely a factor, I am coming to the conclusion that the 12" is the most sought after model so they jack up the price. I'm not saying that is a condescending way, I'm sure I'd do the same if I was in charge. 12" is a bit too large for my purposes anyhow, if the jump was only $100 I doubt if I'd get one.

 

I keep an eye on craigslist, so far only ultra low end kids telescopes but you never know when a gem might pop up.



#20 JMW

JMW

    Soyuz

  • -----
  • Posts: 3,779
  • Joined: 11 Feb 2007
  • Loc: Nevada

Posted 20 January 2020 - 12:38 PM

Consider push to. Buy a Dob 10K encoder kit from Skyeng.com. Buy a Nexus DSC that you can use to help find objects.  Have Astrogoods make you a quality birch ply clam shell base. Buy a quality newtonian tube of your choice. This works well up to 12 inches. After that you are in collapsible Dob territory. You will have a quality experience with a much lighter base which makes moving and setting up more enjoyable. The Nexus DSC will make finding targets very easy. Hand tracking of objects on a quality mount is very easy.

 

Most of the commercial Dob bases are very heavy particle board with an exterior laminate. Birch ply is much stronger and lighter. Many off the commercial Dob bases have inadequate altitude bearing sizes.

 

I have a Webster D14 with a 14.5 inch f/4.3 Zambuto mirror and ServoCat that I bought used for about $5000. I use my smaller scopes more often because I don't bother with the bigger Dob unless I am camping at a star party for several nights. I am using a TEC 140 and Teleskop-Express f/6 8 inch newtonian on a Dob base for most of my non-astronomy centered trips with my travel trailer.

 

I you are patient and are willing to drive to the buyer to inspect the scope and save the hassle of shipping, much money can be saved by buying used.


  • vdog likes this

#21 vdog

vdog

    Apollo

  • *****
  • Posts: 1,284
  • Joined: 30 Aug 2018
  • Loc: California Central Valley, U.S.A.

Posted 20 January 2020 - 12:55 PM

Only with goto dobs though, 10 to 12 jump in manual is $340 vs $970 for gotos.  Mounting indeed likely a factor, I am coming to the conclusion that the 12" is the most sought after model so they jack up the price. I'm not saying that is a condescending way, I'm sure I'd do the same if I was in charge. 12" is a bit too large for my purposes anyhow, if the jump was only $100 I doubt if I'd get one.

 

I keep an eye on craigslist, so far only ultra low end kids telescopes but you never know when a gem might pop up.

Yeah, I don't see a lot of quality stuff on Craigslist either, and when there is people want too much for it.  All my used gear has come from CN.

 

Me, I kind of regret not getting the 12-inch, but that critical point I referred to earlier is also where the scopes start to get bulky and heavy.  That's my understanding with the 12 inch dob; it is significantly bigger and heavier than the 10-inch.  So, I figure if I'm going to go bigger, I might as well wait until I can jump up to a 14-16 incher.

 

As JMW points out above, there are other options besides Goto and some that can be added later.  And there are 10-inch dobs in the classifieds right now going super cheap.  I bought new before I'd thoroughly investigated the possibility of buying used, another thing I regret.


Edited by vdog, 20 January 2020 - 12:56 PM.


#22 Xxray

Xxray

    Vostok 1

  • -----
  • topic starter
  • Posts: 100
  • Joined: 23 Feb 2014

Posted 20 January 2020 - 01:11 PM

Well as of right now I am set on a collapsible 10" goto dob, and that drastically limits my choices [to 1], and odds of finding one used is very slim. Maybe I'll change my mind, I doubt it and I hope not, actually a sense of relief when you finally resolve a choice out of so many. Only thing that could really change my mind is if I start reading a slew of negative reviews, not a whole lot of info out there on this particular model but what there is seems very good. Main drawback seems to be it needs collamination every single time it is collapsed, I guess I'll have to see my way into becoming an ace collaminator !



#23 Starman1

Starman1

    Vendor (EyepiecesEtc.com)

  • *****
  • Vendors
  • Posts: 44,168
  • Joined: 23 Jun 2003
  • Loc: Los Angeles

Posted 20 January 2020 - 07:32 PM

Am considering a dob come this spring, am likely going to go with a goto collapsible design. Not much to chose from with those specifics, Skywatcher series is about it.

 

As of this writing, a 8" costs $913, a 10" $1,135. 12" will set you back $2,105, a 14" $2,555 and a 16 $3,400.

 

So a 2 inch jump from 8 to 10 is an even $222. A 2 inch jump from 10" to 12", on the other hand,  is $970, hmmmm. So have we established that slightly larger dobs are insanely more expensive than the next lower model ? Not really, for a 2" jump from 12" to 14" is just $450. But eegads, a 2" jump from 14" to 16" is $845.

 

I assume there is some logical production reason why pricing is so illogical and all over the place, anyone care to take a guess ? I am likely going to go with the 10" but am curious why it would cost an extra $970 to go from a 10 to a 12 but only $222 to go from an 8 to a 10.

When you increase the mirror from 10" to 12", the area increases by 34.6 in²

From 12 to 14", the increase is 40.8 in²

From 14" to 16", the increase is 47.2 in²

The 2" increase is resulting in more glass on an increasing scale.

 

And, accompanies a larger secondary, larger mirror cell, larger secondary holder, larger tube or tube segments, longer poles, possibly of larger diameter, larger bases, larger bearings, etc.etc.

And don't forget that smaller scopes sell in larger numbers, so the costs are lowered per unit.

The real question is not why the large scope sells for its price, but how the manufacturer can offer the smaller scopes so cheaply.

 

The following shows that larger scopes take more materials and take longer to make:

The analysis of price--8" is $114/inch.  10" is $114/inch   12" is $175/inch  14" is $183/in  16" is $213/in

That tells me the manufacturer makes more 10" scopes than the other sizes.


Edited by Starman1, 20 January 2020 - 07:33 PM.

  • kfiscus, vdog and SillySMS like this

#24 25585

25585

    Fly Me to the Moon

  • *****
  • Posts: 7,423
  • Joined: 29 Aug 2017
  • Loc: In a valley, in the UK.

Posted 21 January 2020 - 11:30 AM

I would more happily consider a longer FL, slower Dob than the faster alternatives. 8" F8, 10" F7, 12" F6, 14" F5, 16" F5 would be appealing. Mirrors for those can be bought, but not complete OTA & or mount units.

 

My 10" F6 is nearest and an 8" F8 or 6" F11 is possible. Some forum members have 12" F6 & 14" F5 I have seen in posts. But 16" & greater are normally below F4.5 and 14" between F4.5 & F5.

 

A S-W 14" F4.5 is, I suppose nearest to what I could upsize to, or Orion XX14G. Possibly a Meade Lightbridge 16" F4.5 as Meade don't make 14" models. A 16" would be better as I have a 12" F5 already, but may be too large. Going from big-small to small-big, at senior citizen age, is a reality check.


Edited by 25585, 21 January 2020 - 11:49 AM.


#25 Xxray

Xxray

    Vostok 1

  • -----
  • topic starter
  • Posts: 100
  • Joined: 23 Feb 2014

Posted 21 January 2020 - 11:51 AM

I will sell you my skywatcher GOTO 16" for $2000cool.gif I think I'm going to focus on upgrading my 10" or go for a premium 12.5"

Sounds like a heck of a deal, shouldn't have any problem getting that - Way too much scope for me though




CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics