Sunday, April 29, 2007

Observatory Shootout

SkyShed POD vs. Thinking Outside SmartShed

Last spring when I decided I was finally going to go ahead with building an observatory, a Canadian company called SkyShed announced their plans to produce an inexpensive plastic observing dome, the SkyShed POD (Personal Observatory Dome) and called for beta testers. I immediately replied, but like about a thousand other people, wasn't selected.

Since I wasn't selected to test, I went with Plan B and purchased a SmartShed Deluxe by Thinking Outside at my local Sam's Club. I did a lot of research online about converting a storage building to a backyard observatory, and the SmartShed kept showing up. But I always had a nagging question: Did I make the right choice?

It turns out fellow Dam Astronomer Andy Raiford did make the cut to test the POD, and it recently arrived in his back yard. I went for a visit and made some notes comparing his POD to my SmartShed.

First Look

There's no denying it: the POD is cool-looking. You know when you see it that you're looking at an observatory. SkyShed got the proportions right and built a handsome building.

My SmartShed? Well, it's not unattractive--I think it looks a whole lot nicer than most storage buildings--but it doesn't look like an observatory. But is that a bad thing? The POD just screams, "Hey! There's a telescope in here!" while the Smart Shed doesn't say anything at all. Call is security through obscurity, but I don't mind not drawing attention in my suburban back yard. Let's call the outside looks a draw.

Seeing the Sky

SkyShed made an interesting decision building their dome. Rather than follow the traditional design of a slit along one side of the dome, they chose a clamshell design. The dome is split down the middle and pivots open at the base, opening up the whole hemisphere. It's cleverly done, and eliminates some dome drawbacks. There's no need to rotate the dome during an imaging or observing session to keep a slit aligned with the telescope. You can also stand in the building and see a big chunk of sky instead of just a sliver. The downside to a clamshell design is that unless you offset your telescope from the center of the dome, you can't point it straight up at the zenith. There's a lot of online debate going on about this: Some see it as a major drawback, as the zenith is the best place to observe in the sky as you're looking through the least amount of atmosphere. Others feel that the obscured portion of sky is too small to be of consequence, and that you can't image at the zenith with a German equatorial mount (GEM) anyway due to a situation called "meridian flip."

The SmartShed roof opens differently. It's also in two pieces, but rather than pivoting on a hinge, one half is lifted up and slides over the over. The building wasn't designed to have an open roof, but it's a happy feature with the way Thinking Outside put it together that it works without modification. The open roof does interfere with part of the sky though--I lose views to the north below about 25° elevation. East, South and West can be accommodated to the horizon by opening a door, but in my back yard the sky is obscured by houses before the walls become an issue.

After looking at both setups side-by-side, I think I prefer the SmartShed's opening. It does take a little more effort to unscrew four connectors and slide the roof off, and realigning everything at the end of the night and putting it all back together takes more time than simply swinging the dome closed, but I like the big view of the sky. I also don't have to think about offsets or turning the dome to any particular direction.

Controlling the Elements

I see having a backyard observatory as serving two purposes. It allows you to permanently mount a telescope so that it's available any time the sky's clear. You can simply open the roof and begin observing. The other reason is to control the elements--wind, cold and light. WInd and cold are related (duh), but even on warmer nights wind can present a challenge to observing or photography as it tries to push your telescope around. And while an observatory can't do anything about skyglow from urban lighting, it can shield you from the neighbor who insists on leaving his back porch light on all night.

I'll admit up front I haven't spent a night observing in a POD, but I have a pretty good imagination. I don't see the clamshell offering a whole lot of protection from the wind. The way I see it, unless the wind is coming directly from behind the open dome, the open half is going to act like a funnel and capture every breeze. As for the neighbor's porch light, the relatively low walls won't block much light from your eyes. This is where a traditional dome would have an advantage with its smaller opening.

The SmartShed has remarkably good protection from the elements despite the open roof. The high walls do a good job of deflecting most of the wind, and completely block all outside light when I'm sitting down. I find I can get as dark adapted as the skyglow will allow, and there is no white light showing in any direction. I think I can stay warmer inside too, by staying under the covered section.

Interior Features

There's no contest here. The SkyShed POD is a seven-foot diameter circle with about 38 and a half square feet of floor space. The SmartShed is a seven-by-eleven foot rectangle with 77 square feet of floor--more than double the POD's. The rectangular elevation of the SmartShed means more headroom, too. The POD can be equipped with bays to increase the covered storage, but unless you crawl, you can't actually get in them. Even with a table and an observing chair there is still plenty of room for two adults inside the SmartShed. The SmartShed also comes standard with built-in adjustable shelving.

A second major interior difference is the floor. The POD is intended as a portable building, and does not include a floor, unlike the SmartShed's full floor. No floor is an advantage for using a tripod, but I like having my pier coming up through a hole in the floor. I just don't see the need for a portable observatory, and you'll need a full-size pickup or a trailer to move the POD, so I'd rather have a floor. I don't know how weather-tight the POD is, but I can say that my SmartShed has never leaked, even during some pretty intense thunderstorms. I wouldn't want to leave anything on the ground inside the POD. I imagine there's going to be a lot of seven-by-seven decks built below PODs. The POD and the SmartShed are built from similar materials and can be assembled in roughly the same amount of time.

The Bottom Line

Regular price for a SkyShed PODis $1,495, with shipping to my door in Texas an additional $664. Shipping to other states varies from $365 to more than $900 to the Florida Keys.

A Thinking Outside SmartShed Deluxe is $795 at Sam's Club. I picked mine up at my local store, so there was no shipping costs. The Sam's web site estimates $267 shipping to my ZIP code. The only modification required for using the building as an observatory was cutting a 12-inch hole in the floor with a jigsaw for the concrete pier to protrude through.

I don't have that nagging question any more. The POD is cool, no doubt, and SkyShed should sell a lot of them. But in my opinion, the Thinking Outside SmartShed Deluxe is more useful and a better value.

Be sure to read the comments for Andy's rebuttal. He has more experience with the POD, and I appreciate his feedback, particularly concerning the floor and wind.


Andy Raiford said...

Heya Jeff,

I had no idea when you came over to see the POD that you were gathering info for an article. Since the POD is still in beta-testing phase, you may not have gotten the entire story. We (the beta-testers) have been sending in suggestions and ideas for improvements which are being implemented for the public release in a few weeks.

It actually has stormed ferociously a couple of times since the POD has been up and both times, the ground inside the POD was bone dry while everything outside the POD was totally soaked. I purposefully left things like paper and metal around the POD to be good indicators of whether the water was there and I just didn't see it. Bone dry.

The walls of the pods are double thickness which gives a good bit of insulation for protection from heat and cold. I have a remote weather station inside the POD that transmits information to me about temperature, humidity and barometric pressure inside the POD. From what I've seen so far, the POD's insulary material, it will be a fantastic place to protect equipment.

You might also think about the shape of the structures. Imagine yourself not living in central Texas. Imagine you're living in Winnepeg, Canada or even Michigan. Now imagine walking outside after two feet of snow has fallen. Guess which roof will have two feet of snow stacked on top of it? You guess right. The FLAT roof. Dome shapes have their advantages.

As to the height of the walls. Although I've only had the POD for a couple of weeks now, I find that the four foot tall walls are more than adequate to the task of blocking the neighbor's light. When I'm taking photos, I'm seated at my table. I never see the lights.

As to space. Well, the model you saw when you came over is a beta-testing model which has no POD bays. The bays will effectively clear the floor of the computer table and eyepiece cases. The POD bays will have optional shelves.

Wind blocker? I've taken photos from the POD on a couple of breezy nights. You know the ones. After the storms blew through we had a couple of clear nights with some fairly stiff breezes. I normally would not try astrophotography on nights like that, but the POD did indeed block the wind. Will it block all the wind? I doubt it. Have you ever been to McDonald observatory on a cold windy night? That was the coldest, breeziest observing I've ever done in my life. That opening 50 feet over our heads let in enough breeze to freeze our little tushies off. If the dome at McDonald Observatory won't stop all wind, I kinda doubt that the 8-foot POD will either.

I'm not exactly sure how to address the "domes attract theives" theory. It would be easy enough to contact people who own domes around the country to see how often they have to fight off scope-rustlers.

Anyway...I'll be uploading my first multimedia POD article tomorrow.

Later dude,


Jon Bosley said...

I have had the Pod on my list since it first came to light on the webb. I was intending to get one before xmas but it hit delays (which looking back should I should have expected as it is a new designed product). The main problem I now have with the pod is not any part of its design, it is the price. Orginal price was to be around $1000 and a few hundred shipping. Now with shipping to my loction it comes in near 2.4K! In a nut shell its starting to get close to other Domes. Its price is pushing it out of the market it was intended for. SkyShed have said there is not much they can do about the shipping costs. It is sky high because they increased the weight from the orginal design by around 100lbs.

I have not heared of the SmartShed before but it does look like it has a number of good points. The floor is a good plus factor & the price is spot-on. In all fairness I do not believe it is a better design then the Pod but at 1/3 the cost (for me), no waiting, floor, it is a very attractive option. The high walls on the none door side are its biggest drawback.

Jon Bosley

Ed said...

Hi Jon, I went through the same thing you described. I had very high hopes for the POD and followed its progress closely. I was initially going to build a SkyShed roll-off observatory but the news came out about the POD around the same time. Initially, it was to be priced relatively cheap and, even though it's small, I thought it would be a good deal. After waiting a year and seeing the final numbers at about $2500 delivered I couldn't, in all good conscience, buy one. The lack of viewing at zenith was a big factor too but the shipping costs killed it for me. If I lived closer and could pick it up myself, I'd have a POD in my backyard now. Seeing this, I searched a bit and discovered the Exploradome. I made my decision to buy one at a very good time as they were coming to NEAF and I live fairly close in NY. They gave me a great price, about $1200 delivered with all the accessories. I've already bought all the other material for the base including all the electric and vinyl siding, all of which cost another $1000. So for about $2200 I get a 10' x 10' observatory with electric, full zenith view and plenty of room inside for "stuff". All in all I think the POD has it's place and Wayne will sell many of these. It is VERY well made and looks to be a winner. I just don't think it fills my particular circumstance.

Herman Zwirn said...


I thunk I was the first person to use a Thinking Outside Smart Shed as an observatory. You can see that story on the MAPUG web site. I have been referenced by sveral other astronomers as they buuilt the Smart Shed. I have had it coming up on three years.

The shed has more square footage than the POD, but the telescope only fits in one half. That spac is less than the POD and not circular.

Both have double (air spaced) walls for insulation. The Smart Shed has higher walls, but the wind is pretty fierce sometimes in Iowa. It blocks the wind hittinmg me but not the scope. At my age lifting the roof off and on has become problematic. I have become used to a roll off roof and prefer it to a dome with a slit. The POD presented me with a compromise.

I will be replacing my Smart Shed with a an LX3 POD this spring. It will be holding a Meade 12 inch LX200. The Smart Shed will be next to the POD and will have a new function.

The POD is more expensive. I paid $675 at the Ames Iowa Sam's Club and carried it back to the farm. The POD is over 2K with "to door" shipping.

We are lucky because there are many choices for us. I've looked at the field and selected this one.

Enjoy the dark everyone,


Andy Raiford said...

This article from Cloudy Nights should say it all.

Andy Raiford

Anonymous said...

Interesting article about the Smart Shed, just what I need more choices,lol. It may seem simple but I like the look of the POD and since it will be in the middle of our backyard my wife has already said no storage shed, but she liked the look of the pod so guess who wins.

bob j

Anonymous said...

Well I almost built a roll off OBS,
though about converting an existing 12x14 foot shed into a Roll off..
looked at Clear Sky,Home Dome and Sirus,and Astro Heaven observatories and was active on CN during the design by committee ED...

My major concern was the cold winter weather and ONE DARN light from a neighbor..

The established manufacturers all had real nice and usable observatories BUT honestly they all wanted way more money they I was willing to invest...

Anyway I like the POD...its drawbacks (to me) were the height of the walls and the clamshell roof..both not good enough to keep my taill end warm in winter if the
wind was more then a breeze.. Interior room was a big question

I went with the ED...delivered to
my door it was less then $900 cost me another $1100 for materials & electric paint carpet and lumber etc.. to build a base building and I am thrilled how it handled last winter...I ordered it early ..pre
initial availability etc..and yu bet it is now even more expensive, and they are also raising the prices again in June.. So the increased POD prices still leave it (money wise) at the bottom of the pile (a good thing)

I was not interested in its portability (another good thing) BUT I do believe after using my ED for 8 -9 months that the base POD would absolutely need 3 bays at would be surprised what "stuff" ya gota have inside lol.

The POD should be the answer for a lot of guys and gals in their quest for an observatory.. I like it even though for my needs it just did not fit the bill...

That said I discovered that the MAJOR PLUS for any observatory is
just having the scope available to use 24/7 in minutes no set up no breakdown every session etc leads
to a heck of a lot more time spent at the eyepiece...

Just my opinion..

Bob G

imjeffp said...

I'll admit a bias toward the Explora•Dome, even though it wasn't the best choice for my use. It has a cool logo, though!

Anonymous said...

Let me get this right ......

Because you weren't selected to get a POD free (neither was I, boo hoo, I got over it in 5 seconds) you went something like 'stuff this, I know - I'll put my 'scope in a cheap shed !' ?

And then you make a point of finding a beta tester (ie someone helping finalise the design, who has an early version of the unit, not the version that's on sale) and write a spoiler to his report & article ? As well as slagging off the POD regardless of you having no actual first-hand knowledge of how water-tight, wind-tight, light-tight or portable it is ?

Well, good luck with it; I suggest you have a pop over to this article in CLoudy Nights forums :

Still want to leave your expensive 'scope in a cheap shed that will collapse & wreck it ? The PODs have passed the same winds ......

imjeffp said...

Dude (or Dude-ette), try the decaffeinated brand. I hear it's just as tasty as the regular stuff.

imjeffp said...

A follow up two years later:

We recently had a windstorm that left a section of my wooden privacy fence on the ground--I don't know the actual wind speed, but it had to be pretty significant. I'm pleased to report that the SmartShed showed absolutely no ill effects. We've also had a couple of hailstorms, one with golf-ball sized and up hailstones. My neighbor's metal shed is dimpled like a golf ball, while my shed looks as good as the day it went up.