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Go Big, but how Big?

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#1 Bashbelly

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Posted 29 April 2013 - 10:34 PM

Anyone have any input on whether a 32 inch mirror is too big versus a 28 inch mirror in overall terms of handling? Is this always a 2 person job to put together, or can it be done by one? Specifically thinking about F/3 or F3.3

Transportation is not an issue (enclosed trailer). Not afraid to get on a ladder :grin:

#2 JMW

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Posted 29 April 2013 - 11:36 PM

I would talk with the makers of the scope. Some scopes have truss rings that make it easier to deal with the UTA. I camped next to a homemade 40 inch dob. The guy used a winch to load the 800 pound scope up the ramp into the trailer.

#3 hbanich

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Posted 29 April 2013 - 11:59 PM

There are many variables, and they have different values for each of us, but having a 28 inch f/4 for the past 9 years I can speak to my own experience. Hopefully it willbe helpful.

First of all, I'm 6'4", 220 pounds, 57 years old and still relatively strong. I move my scope by wheel barrow handles that feel like an approximately 50 pound lift when moving the scope. After this much time happily using my scope I'm actively contemplating building a larger one, but not a heavier one - the plan is for the larger scope to be lighter. So for me it comes down to how much the scope weighs, not how big the mirror is.

I have to transport my scope to use - I live near downtown Portland, Oregon, so it has to be easy to transport, set up and break down or I won't use it. My 28 is easiest and fastest to set up by myself, and I really don't know if my scope was simply scaled up to a 32" if it would be just big enough to become a hassle or not.

I'm not tempted to move from a 28 to a 32 because the views wouldn't be enough to justify the move, so I'll never really know the answer to this question for myself.

If you're asking about handling just the mirror, the answer is probably the 32 will always be a two person job to handle, but then that's true of a 28 for most people. I can just manage it but I'm pretty sure a 32 would be just a bit too much for me. Thank goodness I only take my 28 mirror out the scope once a year to wash it - that's plenty!

#4 sn1987a

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Posted 30 April 2013 - 01:30 AM

There are many variables, and they have different values for each of us, but having a 28 inch f/4 for the past 9 years I can speak to my own experience. Hopefully it willbe helpful.

First of all, I'm 6'4", 220 pounds, 57 years old and still relatively strong. I move my scope by wheel barrow handles that feel like an approximately 50 pound lift when moving the scope. After this much time happily using my scope I'm actively contemplating building a larger one, but not a heavier one - the plan is for the larger scope to be lighter. So for me it comes down to how much the scope weighs, not how big the mirror is.

I have to transport my scope to use - I live near downtown Portland, Oregon, so it has to be easy to transport, set up and break down or I won't use it. My 28 is easiest and fastest to set up by myself, and I really don't know if my scope was simply scaled up to a 32" if it would be just big enough to become a hassle or not.

I'm not tempted to move from a 28 to a 32 because the views wouldn't be enough to justify the move, so I'll never really know the answer to this question for myself.

If you're asking about handling just the mirror, the answer is probably the 32 will always be a two person job to handle, but then that's true of a 28 for most people. I can just manage it but I'm pretty sure a 32 would be just a bit too much for me. Thank goodness I only take my 28 mirror out the scope once a year to wash it - that's plenty!


I agree with you 100%, My 28" mirror is as much as I can handle on my own (its not a pretty sight :shocked:)a 32" would be a bridge too far. I haven't used a 32" either but I think the 28" is the "Goldilocks" big dob from a handling point of view.

Barry

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#5 Erik Bakker

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Posted 30 April 2013 - 06:31 AM

That's a real nice scope Barry! And sky conditions look mighty fine on that location. Hat of for carrying a 28". And I can see and understand that it is worth it.

Personally, I am a convenience oriented backyard astronomer. Having some pretty good skies, my backyard is not quite like a rural/desert site. I enjoy putting my 16" outside from my home to my yard in just 2 sessions: 1 for the OTA and 1 for the rocker box . No assembling/disassembling required. In that way it takes less time and effort to be out observing with my 16" than my equatorial 4" apo. I wouldn't dare going bigger than even a lowly 16" because of that.

I admire everybody's courage for going the 28" + route and bringing them to rural sites :bow:

#6 sn1987a

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Posted 30 April 2013 - 08:21 AM

My 28 is still fairly new and I've only had it out a few times (I'm looking forward to the next new moon I can tell you). I am getting a lot quicker and more efficient at assembly and breakdown now and I can honestly say it takes no longer to set up my 28 than it takes for most other scopes.

The mirror stays in the mirror box and would only come out about once a year (like Howards scope above) for cleaning or maintenance. The mirror box has wheelbarrow handles and the weight is within the capability of most people.

I carry the scope in an enclosed trailer with a ramp door so in and out is very quick and easy. Once I've got the mirror box out where I want it, its simply attach the truss poles, hop up the step ladder and attach the UTA recieving ring, pull down the ring/truss assembly to @ 30 degrees and tie off on a suitable weight then clip on the UTA (surprisingly light for its size) from ground level, done!. The rest is details. It is so quick to assemble and take down that I find myself setting up in my back yard quite often to look at the moon and planets.

I hire the enclosed trailer at the moment but eventually I will have my own. Truly the biggest pain is the two to three hour drive out of the city to dark skies.

The views?, well all I can say is wow!. When you go from a push pull 16 Lightbridge to a Webster 28 with Argonavis and Servocat tracking, ha!. Man I live for those precious all nighters.

#7 GeneT

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Posted 30 April 2013 - 08:33 PM

I have to transport my scope to use - I live near downtown Portland, Oregon, so it has to be easy to transport, set up and break down or I won't use it.


In my opinion, this is the key question. Where will you be doing most of your viewing? If in your back yard, then no problem. If you have to haul, set up, and take down everytime you view, then the equation changes. I recommend you check out some telescopes this size to ensure the size you can handle. A trailer will be one solution, and for many a good one, for those with large telescopes.

#8 JMW

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Posted 30 April 2013 - 09:12 PM

I have a trailer. I bought a 5x8 cargo trailer for astronomy camping. There is also the hassle factor of hooking up the trailer and possibly having to back it into a tight space when returning home. The reduced gas milage of pulling a too large of trailer is also an issue. The tight space is the problem at my home. I am lucky that I can keep it on my property. Some HOA require the trailer to be in the garage.

I have thought about getting or making a micro trailer that would just fit the dob. It could be a box with a back door and a ramp that folds up in half. It could be long enough for the UTA to sit behind the dob between the wheelbarrow handles. It could have a shelf above for the truss tubes. I think a 3.5 wide by 6 long by 3 high would be perfect. I would still use the bigger trailer for multi-night camping trips.

#9 JMW

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Posted 30 April 2013 - 09:29 PM

I just looked at Harbor Freight. You could get a 40" x 48" trailer frame that supports up to 1090 pounds with 12 inch tires for $222. It only weighs 151 pounds. You could build a box on that frame to haul you dob and it would fit well behind your vehicle without adding a lot of drag. The frames only about 10 inches above the ground so the ramp could have gentle slope without having to be long. It's already DOT legal so you would only have to worry about building the box and ramp. You could hand push the trailer into tight spots on your property with a dolly.

http://www.harborfre...48-inch-mini...

http://www.harborfre...olly-37510.html

#10 EJN

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Posted 01 May 2013 - 10:35 AM

Keep in mind that an extensive medical study found the leading cause
of hernias in men over 40 is owning big dobs.

#11 GeneT

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Posted 01 May 2013 - 04:50 PM

There is also the hassle factor of hooking up the trailer and possibly having to back it into a tight space when returning home.


If living in suburbia, one needs to park the trailer in the garage if the telescope remains inside. An amatuer astronomer here in San Antonio had a large Dob stolen, along with his trailer a few years ago. He did get it back about six months later. One reason I never went the trailer route is because I have a two car garage and keep both cars inside. I wouldn't trust leaving a trailer outside due to vandals.

#12 JMW

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Posted 01 May 2013 - 05:07 PM

I think a trailer is pretty safe if you lock it behind a backyard fence out of site from the road. It's as safe as a shed or observatory. I have two trailers locked with cables. I have an obvious security camera on it with a 2 watt LED light barely illuminating the trailers but good enough for the low lux camera. Several years ago someone tried to move my open bed trailer by hand and gave up after he ran up to the end of the steel cable.






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