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Why is Orion the only dob with a handle under the front opening?

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#1 stargazer193857

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Posted 28 November 2019 - 09:22 PM

Skywatcher, zhummel, explorescientific all don't put handles under the ends of their dobsonians. Why?

#2 stargazer193857

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Posted 28 November 2019 - 09:24 PM

Skywatcher, zhummel, explorescientific all don't put handles under the ends of their dobsonians. Why?

https://www.cloudyni...24454-dob-knob/

That is what I'm talking about. The poster says other companies used it, but I've only ever seen it on Orion scopes.

How long have those been around? Also called navigation knobs, for slewing the scope.

Edited by stargazer193857, 28 November 2019 - 09:44 PM.


#3 wrvond

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Posted 28 November 2019 - 09:44 PM

Cost savings would be my guess. Mostly I just grab the edge of the opening. Don’t think I’ve used the knob more than twice.



#4 stargazer193857

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Posted 28 November 2019 - 09:45 PM

Cost savings would be my guess. Mostly I just grab the edge of the opening. Don’t think I’ve used the knob more than twice.


Is there an active patent on it? It is a great idea. I think the part only costs 50 cents to make.

#5 lemonade

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Posted 28 November 2019 - 09:54 PM

Skywatcher, zhummel, explorescientific all don't put handles under the ends of their dobsonians. Why?

Hehe, you've got a good point. I find myself often reaching for the edge of the opening in order to move the tube on my newt easily. Handles should be an industry standard especially for those big dobs. Can't be hard to add them or cost much to do so.



#6 coopman

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Posted 28 November 2019 - 10:04 PM

Simple greed by the makers.  They would make 25 cents less per scope sold.  Go to Home Depot & get a knob.


Edited by coopman, 28 November 2019 - 10:05 PM.

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#7 stargazer193857

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Posted 28 November 2019 - 10:16 PM

Simple greed by the makers. They would make 25 cents less per scope sold. Go to Home Depot & get a knob.


Definitely true for not flocking the first 12" of the tube. Many people would get hooked on the hobby faster if the view was not washed out.


But why do you think everyone is greedy except for Orion? Orion includes them.

#8 Barlowbill

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Posted 28 November 2019 - 10:39 PM

I spent like $2 for a wooden cabinet handle at Lowe's, painted it and bolted on my Orion Dob.  It came with the hole but the previous owner kept it.  


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#9 wrvond

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Posted 28 November 2019 - 10:42 PM

Lay one of those tubes across the back seat of your car then try to lift/drag it out without bending that knob. I have found that knob to be more of an inconvenience than a help.

Take a moment to bend over the focuser then reach under the tube near the opening where a knob would be. It’s not nearly as easy or intuitive as simply grabbing the edge of the tube near the focuser.


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#10 stargazer193857

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Posted 28 November 2019 - 10:44 PM

I spent like $2 for a wooden cabinet handle at Lowe's, painted it and bolted on my Orion Dob. It came with the hole but the previous owner kept it.


If it costs that little, and is so useful, it makes me wonder why it is not standard on all dibs.

#11 stargazer193857

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Posted 28 November 2019 - 10:47 PM

Lay one of those tubes across the back seat of your car then try to lift/drag it out without bending that knob. I have found that knob to be more of an inconvenience than a help.
Take a moment to bend over the focuser then reach under the tube near the opening where a knob would be. It’s not nearly as easy or intuitive as simply grabbing the edge of the tube near the focuser.


So it needs to be shorter, rounded on bottom, large enough diameter at top for leverage, and green instead of black.

#12 Joe1950

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Posted 28 November 2019 - 10:49 PM

I have a SkyWatcher, 6”, f/8 and it has that knob on the front of the tube. It says so in the link. It’s on their traditional DOBs. 

 

On the DOB I built, 6”, f/6, I just got a $2 white kitchen knob and attached it.


Edited by Joe1950, 28 November 2019 - 10:52 PM.

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#13 Jon Isaacs

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Posted 29 November 2019 - 06:49 AM

My thinking/experiences:

 

- A knob in the right place can be helpful but the right place depends on the individual observer. In my mind the purpose of the knob is not comfort, it's actually more comfortable to grab the edge of the OTA.

 

Rather, it's to keep the observer from touching to metal OTA and heating it. This can cause a tube current that takes 30-60 seconds to dissipate.  Tube currents are most detrimental at high magnifications and if one is touching the OTA even 30-60 seconds to track, they maybe continuous.

 

For this reason, I wear a glove on my tracking hand when using my 10 inch metal tube Dob at high magnifications.  I did add a knob a few years ago

 

With a large Dob, the knob is not needed because there's so much to grab, the upper and lower upper cage rings, the truss poles, the uprights between the rings, even the truss poles. Generally whatever one touches on a truss scope does not cause tube currents.

 

Jon


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#14 lphilpot

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Posted 29 November 2019 - 12:00 PM

I agree with Jon that (for me) it's easier and more convenient to grab the OTA end (or UTA edge) than to try to find a knob in the dark. There's generally 360 degrees of OTA but only one knob.


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#15 wrvond

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Posted 29 November 2019 - 12:39 PM

To be clear, the question was: "Skywatcher, zhummel, explorescientific all don't put handles under the ends of their dobsonians. Why?" And since none of us can possibly know the answer, my WAG was due to manufacturing costs. Only pennies for a knob, you say? Pay pennies for a knob and then add the installation to the production line. Is it installed by a robot or a human? What tools are needed? Sure, the cost per unit isn't all that much, but multiply that cost by thousands and it becomes significant. It's certainly not required to operate the telescope. Perhaps it's things like that knob that put Orion scopes into the higher cost range. How many people buy Zhummel because of the lower cost? Based on my readings of the reflector forum, lots of people. You don't achieve that lower price by adding bells or whistles.

 

So the conversation has devolved into whether a knob is a good thing or not. My position is that it certainly can be a good thing, but don't run right out and buy one without considering things like: it can be hard to reach, it can get damaged in transit, it might not get used at all.

As was pointed out to me, someone using a dew shield can find the knob indispensable - someone with a truss dob, not so much.

 

I've known several people that went to Lowe's and bought a drawer pull knob for a couple bucks and were completely happy. In fact, I'd hazard a guess that this is not the sort of mod that is likely to go badly and ruin a perfectly good scope. ;)

 

Enjoy!


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#16 Ihtegla Sar

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Posted 29 November 2019 - 06:10 PM

My Skywatcher (12" collapsable) that I bought last year came with not one but TWO knobs on the UTA, one on each side. I always forget to use them though and just grab the end of the tube.
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#17 Jon Isaacs

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Posted 30 November 2019 - 06:51 AM

So the conversation has devolved into whether a knob is a good thing or not.

 

That is a necessary discussion to have.  One cannot just assume that the knob is a good thing.  It could be that the reason these other manufacturers do not put a knob on the scope is that they do not think it's a good thing or maybe they're like me and think the placement of the knob is critical and differs depending on the observer.

 

Jon


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#18 wrvond

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Posted 30 November 2019 - 08:26 AM

That is a necessary discussion to have.  One cannot just assume that the knob is a good thing.  It could be that the reason these other manufacturers do not put a knob on the scope is that they do not think it's a good thing or maybe they're like me and think the placement of the knob is critical and differs depending on the observer.

 

Jon

Absolutely.  waytogo.gif


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#19 dan_h

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Posted 30 November 2019 - 02:27 PM

The knob is a poor attempt at providing a means for the observer to adjust the position of the scope.  To meet the intended purpose, it needs to be bigger so it can be gripped (like the edge of the front of the tube) and as others have pointed out, it needs to be located to suit the observer.  And it would probably be more useful if it were strong enough to allow its use when lifting the scope in and out of a vehicle or closet etc.  The little knob Orion has provided just isn't up to the task of providing a solid grip point.  Cute but not functional and certainly not worth copying.

 

dan



#20 stargazer193857

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Posted 30 November 2019 - 02:35 PM

I love the knob on mine. I agree there needs to be something on the tube to grab hold of with one hand.
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#21 SteveG

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Posted 01 December 2019 - 03:02 PM

I added the knob to my 10” dob. Orion used to sell it separately.

 

As Jon noted, it is used to move the tube during high power planetary viewing. It prevents the heat from my hand entering the tube. I think it’s very worth having on a 10” dob. I’ve never had an issue loading the tube because of it.



#22 stargazer193857

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Posted 01 December 2019 - 03:31 PM

It has never given me an issue either, and grabbing it has been intuitive.

Plastic is less painful than metal in the winter.

I think an improvement would be to make it a color other than black, move it an inch closer to the focuser so more people notice it, and make the base a bit wider and height a bit shorter so some people don't bend it as easily.

#23 SandyHouTex

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Posted 01 December 2019 - 03:33 PM

I have the 6 inch, 8 inch, and 10 inch solid tube Skywatcher Dobs and they all have the black knob under the front.  It came that way from the factory.


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#24 kfiscus

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Posted 01 December 2019 - 07:03 PM

I had an Orion XT10 and grew to like that navigation knob.  I moved on to a Zhumell 12 which didn't have the knob, as mentioned by the OP.  When I was flocking the Z12's tube, I added an Astrocrumb filter slide which meant that I had to rotate the spider.  The original spider holes needed dealt with.  3 holes got black vinyl auto plugs and the one at the bottom of the OTA got an Orion navigation knob bought on CN's classifieds.

 

The included photo shows the same treatment done to my 16" Lightbridge.  The bottom of the tube is on the right side of the photo.  Note the auto plug in the hole nearest the camera.

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Edited by kfiscus, 01 December 2019 - 07:05 PM.

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#25 mjulihn

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Posted 01 December 2019 - 10:06 PM

Rather, it's to keep the observer from touching to metal OTA and heating it. This can cause a tube current that takes 30-60 seconds to dissipate.  Tube currents are most detrimental at high magnifications and if one is touching the OTA even 30-60 seconds to track, they maybe continuous.

Hmmmm... seriously?


Edited by mjulihn, 01 December 2019 - 10:07 PM.



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