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Blind-Cyclops
sage
Reged: 11/28/05
Posts: 488
Loc: Kitchener, ON, Canada
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Hello Folks,
OK -- we've all seen the photos, the ones where people are standing on 10-12-14 foot ladders to look into EPs at the top of big, giant, colossal Dobs. There are a number of these photos posted here in Cloudy Nights. Are these the images of truly ... really safe stargazing? Is common sense nowhere in sight? To heck with safety first -- full speed ahead for bigger Dobs.
The question is... Is this the image of safety that the hobby of astronomy wants the world to see? (I think not)
BIG, GIANT, COLOSSAL Dobs are GREAT -- "They are KINGS of the "aperture rules" for amateur scopes. And I'd love to have one too -- a 40 incher (or maybe bigger). However, there comes a point in time -- in the one-up-manship competition and the "gotta-have-one-bigger-than-the-other-guy" -- when enough is enough. I think we've reached that limit and surpassed it by a fair bit. I'm not referring to the aperture size, but rather the total lack of common sense for true and real safety -- particularly in the dark.
The Dob manufactures keep making them bigger and taller... and the ATMers do the same... and people just keep buying taller ladders to reach the EPs. Does anyone get the feeling that it may not even stop once we have Dobs as high as the Empire State Building or the CN tower (anything goes... just to reach the stars)? But why wait until it reaches that extreme?
There are other light-path configurations for telescopes, particularly for the Dob style mounts, that allow people to stand safely and comfortably on the ground while using a 20-30-40 inch Dob -- or at the very most a three step kitchen "handi-step."
Clearly, it will take someone falling off a ladder at a starparty resulting in death or a crippling disability before manufacturers and ATMers decide to select a light path which allows more common sense as well as greater safety and comfort. Hopefully, "that fall" has not already happened.
Various types of compound scopes have proven to be outstanding performers over the past few decades. Why not look for some kind of compound light path for Dobs with apertures of over 16-18-20 inches? There are a couple designs out there -- some invented in the 1860's. These alternate light path designs are in use today at some of the world's best professional observatories. If it's good enough for the pro's, why not the amateurs? Are we too good for "high tech innovations?" I think not. ATMers have proven time and again they have the brains, skills and the can-do attitude to adapt, overcome and modify, to create some wonderful leading-edge telescope innovations -- even if more-so in plywood than in carbon-fiber.
The Nasmyth style of light-path configuration (as well as a couple others) allows for at least three easy ways to reach and use EPs while standing on the ground (as well as for various cameras) -- 1) through the altitude shaft (either side); 2) through the primary mirror and mirror box (Cassegrain/SCT/Mak styles); and 3) the top or side of the mirror box just in front of the primary mirror. This allows for standing or sitting positions -- on the ground with far greater safety and comfort.
I found examples of this and other forms of light-path configurations that can place people's safety first. And I'm sure there are still other designs I'm not aware of. John Dobson started one telescope innovation. Surely, there is another innovation out there for true and real safety -- while still providing awe-inspiring views of the universe through ever larger Dobs.
Enjoy the night sky -- but lets do it through safety first.
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Clear skies...
Duncan 
"Watch the skies, everywhere! Keep looking. Keep watching the skies!"
-- Closing line in movie spoken by newspaper report Ned "Scotty" Scott (Douglas Spencer) in the Sci-Fi movie
"The Thing From Another World", RKO Radio Pictures, 1951.
Antares (refractor) 127mm f/6.45. w/2-spd Crayford
Orion (Maksutov) 150mm f/12 w/2" EP adapter
Giro 3 (twin), 18" pier, EQ5 tripod.
Garrett 20x80mm, 410 head, 055 tripod.
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Mike Lockwood
Vendor
Reged: 10/01/07
Posts: 60
Loc: Usually in my optical shop
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Actually I like to make very large mirrors, but I'm trying to shorten or eliminate ladders.
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Mike Lockwood
20" F/3 MX Starmaster, MX = Mike's eXperiment
14.5" F/2.55 self-built Newtonian
Nine other self-built telescopes, 4.25" to 30"
TeleVue Paracorr, eyepieces
http://www.Loptics.com/
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George N
professor emeritus
Reged: 05/19/06
Posts: 672
Loc: Binghamton & Indian Lake NY
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Well I’ve mentioned here before that I’ve felt uncomfortable observing thru a 36” F/5 standing on a ‘standard’ style step-ladder with the scope pointed near the zenith. However, I’ve done it (very carefully) about a half dozen times. I’ve seen a number of 30+ inch Dob owners with steel rolling ladders with side rails like they use to stock shelves in Home Depot, etc. This type of ladder has a low rectangle shape base with four wheels. They work well and are safe, but they are difficult to transport. A 36 or larger should spend most of its time in an observatory, so transporting the ladder is not an issue. Tom Clark published an article about building such a ladder out of wood for his 40-inch and it looked pretty safe to me.
Several years ago at Stellafane a guy had a home-made 16-inch Ritchey (home-made optics & scope) on a Dob style mount that used a third mirror to push the focus out the center of one alt bearing. The observer had to sit low and of course the eyepiece remained at the same level at all times. Jim’s Mobil (JMI) offers 30 and 40 inch “folded Newts” with three mirrors where the observer sits or stands on the ground. There is of course some light loss with the third mirror, and the flat secondary is very large.
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George N
Obsession 20
Optical Guidance Systems 10" F/9 R-C Cass
6" F/5 & 8" F/8 home-made Newts
MI-250 mount
SBIG STL-1301E CCD
Member, International Dark-Sky Association
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George N
professor emeritus
Reged: 05/19/06
Posts: 672
Loc: Binghamton & Indian Lake NY
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Quote:
.....I’ve seen a number of 30+ inch Dob owners with steel rolling ladders with side rails like they use to stock shelves in Home Depot, etc. This type of ladder has a low rectangle shape base with four wheels. They work well and are safe, but they are difficult to transport....
Here's a picture that I took at Stellafane this year that is of the general type I mean. The scope is an Obsession 25. I've seen even larger ladders of this type being used with big Dobs.
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George N
Obsession 20
Optical Guidance Systems 10" F/9 R-C Cass
6" F/5 & 8" F/8 home-made Newts
MI-250 mount
SBIG STL-1301E CCD
Member, International Dark-Sky Association
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sailor70623
scholastic sledgehammer
Reged: 01/12/08
Posts: 944
Loc: Ok.
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I'd rather fall off a tall ladder than waste away in a bed.
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Corornado PST
LB 16" & 12"
Z 10"
LX50 8"
8" CPC
ETX127
102&90mm MAKs
80mm Richfield APO
70mm refractor
ETX60
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pogobbler
member
Reged: 09/30/08
Posts: 31
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The worst thing to happen, I think, is for legal liability issues to stifle any manufacturer from offering scopes such as the extremely large dob mounted newts that some do, as has happened in many other industries. One hopes the owner of the scope, even if he got injured falling from a ladder while using one of these monster scopes would realize that he took on that responsibility for himself when he bought the scope-- of course, if someone were killed, it might be a tougher sell to a grieving family member. Still, it seems unlikely to become an issue and let's pray it never does.
That said, I agree that as tall as the scopes are getting, some of the alternatives that fold the light path seem a more reasonable option. Yes, you lose light and it'd cost more for more and possibly more complicated optics, but the end result would be so much more user friendly, I'd think. I suppose setup and collimation would be more complicated, too, but, really, who wouldn't rather stay on his feet (or behind) and have large scope views?
I'm a lazy observer, myself, and my own dream scope-- what I might have built once I hit that big lottery-- would be a very large (40"+), dob mounted, with Nasmyth type light path exiting through the altitude bearing, with an observing platform, complete with chair, table, power source, etc., attached to the scope such that it rotates with the scope so I can just sit and observe in comfort. It'll all be computer controlled and driven, too, in my own observatory. Not too much to hope for, is it? 
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Hrundi
Pooh-Bah
Reged: 02/06/08
Posts: 1237
Loc: Estonia
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They're safe enough. As long as the people who use them do so with care, there should be no risks that I'm aware of.
I'm not a huge fan of the over-safe craze this world is going through, though. Not everything has to be padded with soft pillows. What next, kids not being allowed to climb trees?
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skyward_eyes
Carpal Tunnel
Reged: 12/12/06
Posts: 2102
Loc: Arizona
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I understand that the ladders are crazy they come with the territory. I believe all owners of large dobs require large ladders understand the risk, this is why you hardly ever seen a 12"+ or even 16"+ at a public event.
If a ladder is an issue then save up for some rediculously expensive fast dob or get crafty with a folded design.
Like the post said, not everything is going to be safe, but while your observing with a scope like this take your time going up and down the ladder.
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sixela
Postmaster
Reged: 12/23/04
Posts: 10855
Loc: Boechout, Belgium
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Quote:
Not everything has to be padded with soft pillows.
Everyone (or at least the Spanish Inquisition) knows soft pillows are for stabbing.
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400mm f/4.46 self made Dobsonian on Tom Osypowski equatorial platform
Orion Starblast (114mm f/4 reflector, Alt/Az)
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Darenwh
Pooh-Bah
Reged: 05/11/06
Posts: 1224
Loc: Covington, GA
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A person takes his/her risk when using recreational equipment of any kind. If we let fear rule us then we will never leave the house. Biking is at least as dangerous as climbing a ladder to use a telescope. Skiing, sky diving, hang gliding, hunting, running, ice fishing, Mountain Biking, Surfing, etc... All have risks and many of them are far more risky than climbing a ladder.
A person must know their limits and must decide what risks to take on their own. It is a shame that our court system would assign blame for an accident that somebody has because of their choices to a manufacturer of any recreational item.
The use of a telescope is a very controlled item. An observer generally does not go out on very windy days to use the scope. They are not next to fast moving items that are likely to push them off a ladder. It comes down to their own physical skills and balance. If they cannot balance well enough on a ladder then they should not climb it. If they believe they will try to use the scope to balance them then they should not be on the ladder. In short, they should know what they can and cannot do and should be fully responsible for their choices.
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Daren
Covington, GA
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moonyguy
journeyman
Reged: 01/08/09
Posts: 7
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Not too long ago...professional astronomers repeatedly spent several nights in a row in a tiny cage at the prime focus tens of feet up in the air...the worst part is when you have a nature call in the middle of a 2 hour long exposure. At least we can climb off the ladder and attend to the business!
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Luigi
Post Laureate
Reged: 07/03/07
Posts: 4940
Loc: MA
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>>>... standing on 10-12-14 foot ladders to look into EPs at the top of big, giant, colossal Dobs...Are these the images of truly ... really safe stargazing?<<<
I've at times stood on ladders of that height working on my house. I'm sure that wasn't "safe" either. Safety/risk/reward should be decided by the individual involved, not dictated by anybody else.
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17.5" f/5 Dob. IM-715 MCT. 120ED. Lunt 60mm Ha.
Zeiss, Leica, Fujinon, Nikon, Pentax, Bushnell bins
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jayscheuerle
Post Laureate
Reged: 01/16/06
Posts: 4071
Loc: S. Philadelphia, PA
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The standard newt configuration of a dob allows the smallest central obstruction and the least expensive (and least complicated) way to access as much aperture as possible. When you have aperture fever and are shelling out a big wad-o-cash for your primary, you neither want to take away from its light gathering ability or pay extra to grab less light. You should be willing to pay for a better set of stairs though... - j
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Fight indignorance!
The Green Goblin - 12" of dobsonian excellence!
The PortaBowl-a $100 4.5" f/8 ball-scope YOU can build!
Eero2-a 6" f/5 ball-scope you probably can't. 
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lightfever
Pooh-Bah
Reged: 09/27/04
Posts: 1276
Loc: Macomb Michigan
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If someone is not physically adept enough to use a ladder then they shouldn’t use one, it’s simple as that, for many it is no problem.
I have often spent an entire day on ladders that tall or taller at work or at home.
Granted it’s not as comfy as sitting in a nice chair.
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Mark
Tasco 15-TE 76mm
Sky Watcher 80mm ED
AT-111 Triplet
XT8i (with Woden re-figured mirror)
Discovery 12.5" f/5 Premium DHQ (PDHQ Split-tube Dobsonian)
12.5" f/6.3 Dob (Underconstruction)
Celestron CG-5GT EQ Mount
Celestron C4 EQ Mount
"Life is not about waiting for the storm to pass, but learning to dance in the rain" unknown
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Sky Captain
Metal Whisperer
Reged: 11/07/04
Posts: 7190
Loc: Issaquah, WA.
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Quote:
Enjoy the night sky -- but lets do it through safety first.
Quote:
If someone is not physically adept enough to use a ladder then they shouldn’t use one, it’s simple as that, for many it is no problem.
For the user/owner it's probably not a problem as that person is or is getting used to climbing...they understand.
For others that might not be the case. A lot of people don't like to climb ladders much less in the dark and even much less doing it pretty late in the evening when some are not used to staying up late. It is a combination that could pose a problem, and it would definitly be up to the owner of the large dob to make sure his ladder/equipment is safe and sound.
For me, well I hate heights, and given the fact that when I was younger I worked as an electrician for over 10 years and had to climb the worlds scariest three legged 20 ft. ladders...I never got used to it.
But on the other hand, I was at our Mt. St. Helens (volcano!) star party a few years back and Steve (buckaroo) had brought his 30" dob for viewing.
I was up to the top of that baby and not even my death of heights was going to stop me!!! Even my daughter (12 at the time) and my wife who both had never been on a tall ladder went right up to the top for a view most people will never see or experiance.
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Equipment Overload!
Kerry
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star drop
Guilty as Charged
Reged: 02/02/08
Posts: 16289
Loc: Snow Plop, WNY
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Safety is paramount. When I have the public over I make sure that I hold and steady the ladder even though it does not need it. Doing so seems to add to the comfort factor. The ground board of my 25" f/5 telescope riding on the cart is approximately 20" above the ground.
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Ted
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dave b
Post Laureate
Reged: 05/10/05
Posts: 3535
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Quote:
The Dob manufactures keep making them bigger and taller... and the ATMers do the same... and people just keep buying taller ladders to reach the EPs.
actually, the trend seems to be that eyepiece heights are getting lower - as mirrors are getting faster.
if you look at some scope company's websites today, you might find that they offer nothing longer than f/4. who would have imagined that even a few years ago?
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dave bonandrini
30" f/5.2 Dobsonian
President of GCAC
Astromart Moderator
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MitchAlsup
super member
Reged: 08/31/09
Posts: 184
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Quote:
The standard newt configuration of a dob allows the smallest central obstruction and the least expensive (and least complicated) way to access as much aperture as possible.
By the time you get into the big ladder games, the aperture is so big, and the probability that the atmosphere will not be limiting the resolution is so small, that you can afford a bigger secondary with negligible loss in the image quality.
But back to the original rant: (Rated 5 on a scale of 10)
All these other systems -- that transmit the image back down to where mere humans are more adapt -- have a problem that is worse than the ladders--stray light.
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cuzimthedad
Just Be Cuz
Reged: 04/09/06
Posts: 3721
Loc: Sonoma, Northern California
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I really don't feel it's a matter of oneupsmanship or ego. Price alone dictates that a serious choice must be made to purchase a dob over 20". A gentleman considering entering the hobby attended our last star party and was blown away with the views presented through my Obsession. When he finally asked "how much and don't be shy" I told him. He has money and even so was shocked when I told him what I had invested overall not including eyepieces.
Most people I have conversed with who own large dobs spent many hours researching their choices before making a final decission. Climbing a ladder is just part of the over all equation and usually has a factor in the final outcome. Simply put, if you don't like to climb you don't buy a tall scope. As far as safety goes, that's why most of us have home owners or health insurance. I never allow an outsider to climb more than two steps to observe through my dob. Even with experiences observers, if they aren't comfortable they don't go up.
The other thing to take into consideration is the number of dobs 20" and over compared to 18" and under is a drop in the bucket which means ownership of large dobs is reserved to a small number of folks who are left to climbing ladders.
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Dan
20" f/5 Obsession
Antares 1529
TV102
Various Naglers, Ethos, UO Orthos and TV Plossls
The Off Fisher Lane Irregulars
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DavidinFL
member
Reged: 08/28/09
Posts: 52
Loc: Navarre, FL
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The people that have larger scopes know they'll need a ladder when they're buying the scope. The companies that make the larger scopes that require ladders only make them because people out there want to buy them. The companies aren't forcing them on people. Even if someone fell at a star party it would not be the scopes fault. It'd be the person who was on the ladder.
What if somone dropped a heavy expensive eyepiece from those heights and it hit someone on the head?
Life isn't safe. My daily drive to and from work worries me much more than climbing a ladder. If someone died in a car wreck going to a star party should we cancel all star parties?
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Orion XT8 - Orion StarMax 102 EQ
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