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						METER-CLASS ASTRONOMY CONFERENCE
 Telescopes, Instruments, and Observational Programs
 
						
						International Conference January 20-22, 2012Pre-conference tour: Volcanoes National Park - January 
						18, 2012
 Pre-conference insider tours: Mauna Kea - January 19, 2012
 Canada-France-Hawaii Telescope (CFHT) Headquarters
 Waimea (near Kona), the Big Island of Hawaii
 
						
						Conference OrganizersCo-chairs:
 Russell Genet, California Polytechnic State University,
						
						RussMGenet@aol.com
 Bruce Holenstein, Gravic, Inc.,
 BHolenstein@Gravic.com
 Local Host:
 Christopher Erickson, Consulting Engineer
 christopher.k.erickson@gmail.com
 Website
 www.AltAzInitiative.org
 
						Conference Introduction(By conference co-chairs 
						Russ Genet & Bruce Holenstein)
 
						Short Version  (Detailed 
						Version Below) (Conference 
						Organizational Specifics) This conference is devoted to a specialty branch of 
						astronomy—the development and use of meter-class telescopes. These telescopes trace their 
						origins to John Dobson and his innovative ideas for 
						making relatively large aperture alt-az telescopes from 
						low cost materials with ordinary tools. Amateur 
						telescope makers have continued to refine these alt-az 
						telescopes which, not surprisingly, have come to ever 
						more closely resemble their huge mountaintop cousins. 
						Heavy, enclosed Sonotubes have been replaced with 
						lightweight, open trusses. Mirrors have become thinner 
						and significantly larger in diameter—supported by 
						increasingly sophisticated whiffletrees. Computer 
						controlled slewing and tracking have been added. 
						Temperature compensated focusers and instrument rotators 
						facilitate long-exposure astro-imaging.
 The Alt-Az Initiative was founded in June 2007 with the 
						express purpose of facilitating the evolution of 
						portable, lightweight, low cost, meter-class alt-az 
						telescopes. The Initiative, from its inception, aimed at 
						achieving much larger aperture portable telescopes than 
						currently existed. Initiative members quickly realized 
						that it would pay to closely examine the technologies 
						already developed for modern mountaintop telescopes, so 
						they initiated a purposeful “tech transfer” program that 
						would, at low cost, innovatively emulate appropriate 
						technologies such as direct drives, thin active primary 
						mirrors, deformable secondary mirrors, multiple mirrors, 
						etc.
 The primary application 
						of portable meter-class telescopes has been, and will 
						likely continue to be, visual observations. Portability 
						allows telescopes to be safely stored at homes and 
						schools in light polluted cities, yet operated just 
						hours away under dark skies. Large apertures allow faint 
						objects to be observed, while low costs inable 
						widespread ownership and use. Thanks to 
						computer-controlled slewing, tracking, and instrument 
						rotation, portable meter-class telescopes are beginning 
						to be used for astro-imaging and, increasingly, in 
						various areas of instrumented scientific research.
 Mirrors, especially low 
						cost, lightweight mirrors, are the key ingredient 
						required for the continued evolution of meter-class 
						portable telescopes. Active efforts are underway to 
						further develop meniscus, sandwich, foam glass 
						composite, spin cast, and layered mirrors. Forces are 
						just beginning to be applied to adjust the figures of 
						lightweight thin meniscus primary mirrors in meter-class 
						telescopes in a manner somewhat similar to their large 
						mountaintop relatives. Similarly, work has just begun on 
						low cost active secondary mirrors which can be “warped” 
						to counteract distortions in lightweight primary 
						mirrors. Such active mirrors can also be tip/tilted to 
						reduce the effects of the wind gusts on portable 
						telescopes. Finally—also similar to the largest 
						mountaintop telescopes—we anticipate that the largest 
						meter-class telescopes will employ multiple mirrors to 
						reduce weight and facilitate their manufacture and 
						handling.
 Recreational visual astronomers are interested in 
						everything they have a chance to see, so the exciting 
						advantage of a high optical quality, one person set-up, 
						meter-class telescope is that there is so much more to 
						observe. Visual observers marvel at seeing the real 
						photons from objects. Some are excited by being able to 
						barely detect the faintest possible objects such as 
						distant galaxy clusters, quasars, and gravitational 
						arcs. Astro-imaging can also benefit from larger 
						apertures and portability.
 Scientific research 
						programs, as is the case with visual and astro-imaging 
						programs, can benefit from larger apertures and the dark 
						sky opportunities that portability creates. In addition 
						to greater program object fluxes, scintillation noise 
						decreases with telescope aperture, so meter-class 
						telescopes have superior program object signal-to-noise 
						ratios for a given integration time.
 There are instances where scientific observations 
						actually require portability. For example, the size and 
						shape (and hence albedos) of smaller diameter 
						trans-Neptunian objects (TNOs) can be determined from 
						occultations observations as a TNO passes in front of a 
						star, casting a narrow shadow that races across the 
						Earth. Since such narrow shadows rarely pass over fixed 
						location observatories, they must be observed with 
						portable telescopes. With larger, meter-class 
						telescopes, many more TNO occultations can be observed 
						than would otherwise be possible.
 Telescopes may also 
						need to be moved to a location not because of some 
						astronomical event, but because the local observing 
						conditions are advantageous in some way. For example, 
						near infrared photometry (especially Ks band) benefits 
						from high altitudes and dry skies. A number of 
						mountaintop observatories, blessed with good roads to 
						the summit, would not mind sharing their skies with 
						portable meter-class telescopes.
 The era of portable meter-class astronomy has been 
						underway now for several decades—ever since large 
						aperture alt-az Dobsonian telescopes first made their 
						first appearance. Visual observations through Dobs have 
						endeared an entire generation of the public to 
						observational astronomy. We hope and expect that the use 
						of portable meter-class telescopes will increasingly be 
						extended beyond visual observation, not only to 
						recreational astro-imaging, but also to a wide variety 
						of scientific research projects. The dark skies beckon 
						the ever increasing numbers of portable meter-class 
						telescopes of all types.
 We maintain that portability doesn’t have to be 
						restricted to “smaller” apertures.
 The 
						only limits should be our ingenuity and what can be 
						legally towed down the road. There is no reason we 
						shouldn’t see portable 2 meter telescopes in the near 
						future, starting first with on-axis light buckets and 
						then spreading to imaging telescopes. There will be many 
						problems to overcome on the way to 2-meter portability, 
						but working together we'll solve them all—one at a time.
 
 Back to Top
 
						Detailed VersionThe 
						conference is devoted to a specialty branch of the 
						astronomy family tree—the development and use of 
						portable meter-class telescopes.  These telescopes trace 
						their origins to John Dobson and his innovative ideas 
						for making relatively large aperture alt-az telescopes 
						from low cost materials with ordinary tools.  These alt-az 
						telescopes more closely resembled their large 
						mountaintop alt-az brethren than other small amateur 
						telescopes which, at the time, were almost all of very 
						modest aperture and equatorially mounted.
 Amateur telescope makers have continued to 
						refine alt-az telescopes which, not surprisingly, have 
						come to even more closely resemble their huge 
						mountaintop cousins.  Heavy, enclosed Sonotubes have 
						been replaced with lightweight, open trusses.  Mirrors 
						have become thinner and significantly larger in 
						diameter—supported by increasingly sophisticated 
						whiffletrees.  Computer controlled slewing and tracking 
						have been added.  Temperature compensated focusers and 
						instrument rotators facilitate long-exposure astro-imaging.
 The Alt-Az Initiative was founded in June 
						2007 with the express purpose of facilitating the 
						evolution of portable, lightweight, low cost, 
						meter-class alt-az telescopes.  The Initiative, from its 
						inception, aimed at achieving much larger aperture 
						portable telescope than currently existed, setting 1.5 
						meters as its initial goal.  Initiative members 
						realized, from the outset, that it would pay to closely 
						examine the technologies already developed for modern 
						mountaintop telescopes, so they initiated a purposeful 
						“tech transfer” program that would, at low cost, 
						innovatively emulate appropriate technologies such as 
						direct drives, thin active primary mirrors, deformable 
						secondary mirrors, multiple mirrors, etc.  Thanks to 
						“free” ATM labor, rapid advances in low cost 
						electronics, innovative engineering, sharing of 
						information, and rapid prototyping, Initiative members 
						are successfully transferring enabling technologies from 
						larger to smaller alt-az telescopes, thus advancing the 
						era of portable meter-class astronomy.
 The primary application of portable 
						meter-class telescopes—discussed in more detail 
						below—has always been, and will likely continue to be, 
						visual observations.  Portability allows telescopes to 
						be safely stored at homes and schools in light polluted 
						cities, yet operated just hours away under dark skies.  
						Large apertures allow faint objects to be observed, 
						while low costs facilitate widespread ownership and 
						use.  Thanks to computer-controlled slewing, tracking, 
						and instrument rotation, portable meter-class telescopes 
						are beginning to be used for Astro-imaging and, 
						increasingly, in various areas of instrumented 
						scientific research.
 To facilitate discussion, we have divided 
						portable meter-class telescopes into three basic types: 
						visual observation telescopes, general-purpose imaging 
						telescopes, and on-axis light bucket telescopes.  Each 
						type is discussed below.
 
						Visual 
						Observation TelescopesThese “eyeball at the eyepiece” telescopes require high 
						quality optics, and need to be easily transported and 
						quickly set up.  They can be either “pure” 
						non-computerized “push Dobs,” or they can be equipped 
						with modest performance go-to/tracking systems.  Image 
						rotators, generally, are an unnecessary and hence 
						unwanted complication.
 The main use of these telescopes is recreational 
						observing, but they are also used for public outreach, 
						education, and scientific observations such as searches 
						for supernovae, faint visual double star astrometry, and 
						faint visual variable star photometry.  The 
						recreational, public outreach, educational, and 
						scientific aspects of these telescopes meld together 
						nicely.  These telescopes appeal to a wide and diverse 
						set of users.  Think modern large aperture Dobs.  
						Emphasis is on 0.4 to 1.0 meter apertures, fast optical 
						systems, convenient portability, light weight, and 
						affordability.
 
						General 
						Purpose Imaging TelescopesThese telescopes also require high quality optics.  One 
						of the most important features of telescopes intended 
						for astro-imaging is their etendue—the product of 
						their aperture in square meters and their well-corrected 
						field in square degrees.  The eye inherently senses the 
						total information content of an image, and it's a basic 
						fact of the physics of astro-imaging that the total 
						information content of an image (the product of the 
						signal-to-noise ratio and the total number of resolution 
						elements in the photograph) is a linear function of the 
						etendue of the telescope and the square root of the 
						exposure time.  Thus, the best systems for astro-imaging 
						have large sensors attached to large telescopes with 
						high resolution, large angular fields-of-view, and 
						relatively short focal ratios.
 To stay on target, telescopes intended for astro-imaging 
						require either superb long-term tracking or 
						autoguiding.  Because they are alt-az telescopes, their 
						fields rotate, so accurate instrument de-rotation is 
						required.  Operating out in the open, general purpose 
						imaging telescopes need to be resistant to wind gusts.  
						This can be achieved by designing inherently stiff 
						telescopes with low aerodynamic cross sections and 
						equipping them with fast response control systems and 
						rapid tip/tilt image stabilization.
 These 
						telescopes 
						are not only useful for recreational astrophotography, 
						but also for the many science projects that utilize CCD 
						cameras and other sensors for astrometric, photometric, 
						and spectrographic observations.  Everyone, scientists 
						included, appreciate large aperture, high resolution, 
						wide field-of-view, general purpose telescopes which 
						they can transport to their favorite dark sky site and 
						set up in minutes.   Think the perfect portable 
						meter-class telescope.
 As with visual telescopes, the greatest interest is 
						between 0.4 and 1.0 meters.  Larger than this, high 
						performance, general purpose telescopes rapidly get 
						prohibitively heavy and expensive.  However, for some 
						science applications, larger effective apertures can be 
						achieved by forming an array of several general purpose 
						imaging telescopes.  Images or data can be combined 
						electronically or optical fibers brought together to 
						feed a single detector, different color bands can be 
						observed simultaneously, or telescopes can be spread out 
						in a line to “map” the shape of an asteroid.  Such 
						arrays of general purpose imaging telescopes would be 
						adaptable to a wide number of uses.
 For the same aperture, general purpose imaging 
						telescopes are necessarily more expensive than visual 
						telescopes, so they occupy a different niche.  There are 
						no free lunches.
 
						On-Axis Light 
						Bucket TelescopesLight bucket telescopes are light concentrators used in 
						those areas of astronomical research where vast 
						quantities of ultra low cost, on-axis photons are 
						required.  There is no more authoritative 
						definition of astronomical terms than the Cambridge 
						Dictionary of Astronomy (Mitton 2001).  Mitton’s 
						definition:
 
						Light 
						bucket:
						a colloquial expression for a flux collector. 
						Flux 
						collector: 
						a 
						telescope designed solely to collect radiation in order to measure 
						its intensity or to carry out spectral analysis.  No 
						attempt is made to form an image so a flux collector can 
						have a more crudely figured reflective surface than a 
						conventional telescope.              Light bucket telescopes are advantageous in 
						those situations where—compared to the noise from the 
						sky background—the noise from one or more other sources 
						is dominant.  Putting it the other way around, light 
						bucket telescopes can be advantageous when the sky 
						background is a small or nearly negligible source of 
						noise. This situation can occur when: (1) 
						the object being observed is very bright, (2) 
						the integration times are very short and hence photon 
						arrival noise becomes important, (3) 
						scintillation noise becomes a dominant noise source, 
						(4) the bandwidth is very 
						narrow or the light is spread out as in spectroscopy 
						resulting in significant photon arrival noise, or 
						(5) noise from the 
						detector is dominant (as it can be in the near infrared 
						if the on-axis diameter of the detector is significantly 
						larger than the seeing spot size).               The on-axis optical 
						performance of light bucket telescopes need not be any 
						better than average lowland seeing and, for many types 
						of observation, can be significantly worse.  Since 
						observations are on-axis, instrument rotators are not 
						usually required.  Furthermore, optical systems for 
						on-axis (or very narrow field-of-view) telescopes can be 
						easier to design and fabricate than for wide 
						field-of-view telescopes.  For example, it is very 
						difficult, over a wide field-of-view, to correct the 
						spherical aberration in a telescope with a large 
						aperture, fast, spherical primary mirror.  On axis (or 
						for a very narrow field-of-view) the correction is 
						relatively straight forward, thus not only allowing low 
						cost spherical primary mirrors to be utilized.  
						Opticians we have talked to point out that the real work 
						in mirror making is not obtaining a spherical 
						surface—the natural surface you get when you rub two 
						pieces of glass against each other, but in forcing the 
						surface to become parabolic and not revert back to being 
						a sphere.  The faster a parabolic mirror the more 
						difficult it is to make, but this is not the case for 
						spherical mirrors.  Finally, spherical mirrors have the 
						advantage that they can be combined together in a 
						multiple mirror telescope to form a much larger 
						spherical surface.  Two of the world’s largest aperture 
						telescopes utilize multiple spherical mirrors—the 
						Hobby-Eberly and South African Large Telescope 
						(SALT)—utilize multiple spherical surface, hexagon 
						shaped mirrors to form 11 meter telescopes that were 
						built at a fraction of the cost of the 10 meter Keck 
						telescopes.Of course there are no free lunches, and because light 
						buckets have, at best, narrow fields-of-view, so they 
						are not, essentially by definition, general purpose 
						telescopes.  Many astronomical telescopes are 
						specialized.  The Hobby-Eberly and SALT spherical 
						primary mirror telescopes mentioned above are 
						specialized spectroscopic telescopes.  The robotic 
						telescopes at the Fairborn Observatory, which began 
						operation in 1983, were specialized for aperture 
						(on-axis) high-precision photometry.  In these and many 
						other instances, the telescope itself has been optimized 
						for a single, dedicated function.  Rather than 
						maximizing etendue, light bucket telescopes march to the 
						beat a different drummer: maximizing, for a given cost, 
						the number of target photons that fall within a 
						reasonable spot size.  Think photon economics.
 The "sweet" aperture range for portable light bucket 
						telescopes is 1 to 2 meters, with emphasis on the high 
						end.  Arrays of 2 meter portable light bucket telescopes 
						would be very useful. Seven 2 meter telescopes would 
						have the light collecting area of a single telescope 
						larger than 5 meters in aperture.  Such an array could 
						be formed into an intensity interferometer that could 
						image details on the surfaces of large nearby stars.  It 
						is surprising that an array of on-axis high speed 
						photometric telescopes could produce an image the 
						largest aperture, high resolution telescopes cannot, but 
						several groups are pursuing the quantum effect intensity 
						interferometry initiated by Hanbury-Brown many decades 
						ago in Narrabri, Australia, when he directly measured 
						the diameters of many of the closest stars with a 
						two-telescope interferometer.
 Set up time for on-axis light bucket telescopes can be 
						longer than other types, as this is not recreation 
						per se, just grunt-work observational science.  
						Similarly, transportation requirements can be more 
						demanding (e.g. sizeable but still roadable 
						trailers).
  PortabilityWe hasten to clearly state at the outset 
						that we are all in favor of fixed-location 
						observatories.  Many folks are fortunate to live under 
						dark night skies, and for them, a fixed-location 
						observatory in their back yard or on or near their 
						campus makes lots of sense.  For those not so blessed, 
						owning or sharing a telescope at a remote, good-weather 
						dark site is becoming an increasingly attractive and 
						economically feasible possibility.
 It is also worth noting that operation of 
						portable telescopes from a fixed-location observatory is 
						very common.  Although the telescopes are perfectly 
						capable of being transported elsewhere, the owner 
						chooses to keep them at home except perhaps for the 
						occasional summer star party or a move due to job 
						relocation or retirement.  Some of us are blessed with 
						exceedingly fine observing weather for months on end, 
						and can simply leave a portable telescope out in the 
						open in our yard.  When the weather turns bad or we head 
						out for a vacation, we can simply roll our telescope 
						inside or take it with us.
 Howard Banich’s now classic definition of 
						portability requires that, on arrival at the operational 
						location, the telescope can be extracted from its 
						transport vehicle and assembled by no more two persons 
						in a half hour or less (see Howard’s “Telescope 
						Portability: Moving a Big Telescope Doesn’t Have to Be 
						Difficult,” in The Alt-Az Initiative: Telescope, 
						Mirror, and Instrument Developments).  Of course a 
						telescope can still be useful even if it doesn’t meet 
						Howard’s requirement, but its likelihood of frequent use 
						will not be as great.  A related issue is the time and 
						effort required to align a telescope once it gets dark.  
						Computerized alt-az telescopes with sophisticated 
						alignment systems can generally be aligned much faster 
						than non-computerized or equatorial telescopes. 
						Built-in GPS and electronic 
						compass telemetry can shave minutes off of the alignment 
						process.  Sidereal Technology’s control systems not only 
						incorporate totally automatic alignment, but mount 
						modeling.  Plate Solve XP, written by Dave Rowe handles 
						Sidereal Technology’s automatic field recognition and 
						centering.
 While it is obvious that if a telescope 
						requires an 18-wheeler to move, or an industrial crane 
						to emplace, it isn’t portable, there are various grades 
						of probability.  We suggest, below, four such grades.
 Ultra-lightweight telescopes 
						are designed to enable a single person to transport and 
						set up a sizeable aperture telescopes.  Two excellent 
						examples of ultra lightweight telescope are those 
						designed and built by Mel Bartels (http://www.bbastrodesigns.com/trilateral.html) 
						and Greg Babcock (http://www.synrgistic.com/astro/24inch.htm).  
						Mel defines ultra-lightweight telescopes as telescopes 
						where the weight of the entire telescope sans primary 
						mirror is approximately one-half the weight of the
						lightweight
						primary mirror itself.  The mirror in Mel’s 
						20 inch telescope weighs 50 lbs, while his entire 
						telescope, including the mirror, weighs only 75 lbs.
 Airline check-in telescopes 
						can be carried as “luggage” on normal domestic or 
						international flights.  Most airlines allow, for an 
						additional fee, overweight (70 lbs) and oversize (80 
						linear inches) bags.  Both ultra-lightweight and airline 
						check-in telescopes should easily fit within ordinary 
						cars for transport.
 SUV/pickup telescopes 
						range from fairly 
						lightweight telescopes easily loaded into a small SUV by 
						a single person in a “wheelbarrow” mode, to telescopes 
						which weigh many hundreds of pounds and require 
						mechanical assistance—such as a winch—to load.  This 
						class of telescopes is too heavy or large to transport 
						on an airplane as check-in luggage or fit in a car.
 Trailer telescopes, 
						in turn, are too 
						large to fit with into an SUV or even in the back of a 
						pickup truck, but they can be loaded on a trailer that 
						can be towed down the road without any special permits.  
						Such heavy telescopes might benefit from motorized 
						wheels or even being built right into the trailer 
						itself.  If you can’t at least 
						tow a telescope down the road by an ordinary 
						vehicle without a special permit, it isn’t a portable 
						telescope.
 Developmental ProgramsDesigning and building portable meter-class 
						telescopes can be challenging, thanks not only to 
						constraints on their size and weight, but also to the 
						demands of transportation and field assembly and 
						operation.  A number of parallel developmental efforts 
						are being pursued by the members of the Alt-Az 
						Initiative.  Their progress had been reported in the 
						recent book, The Alt-Az Initiative: Telescope, 
						Mirror, and Instrument Developments, and on their 
						web site
						
						www.AltAzInitiative.org.  Daily email discussions 
						take place at the Alt-Az Initiative’s Yahoo group.
 While the technology for 0.5 to roughly 1.0 
						meter aperture portable telescopes that weigh a few 
						hundred pounds is not well established, further 
						development would benefit ultra-lightweight and airline 
						check-in telescopes.  The development of technology for 
						portable telescopes with apertures significantly beyond 
						1.0 meters is only now beginning.  The reasonable upper 
						limit to portability is probably about 2.4 meters (96 
						inches), the largest telescope one could transport on a 
						trailer without special permits.     Mirrors, 
						especially low cost, lightweight mirrors, are the key 
						ingredient required for the continued evolution of 
						meter-class portable telescopes.  Active efforts are 
						underway to further develop meniscus, sandwich, foam 
						glass composite, spin cast, and layered mirrors.  Forces 
						are just beginning to be applied to adjust the figure of 
						lightweight thin meniscus primary mirrors in meter-class 
						telescopes in a manner somewhat similar to their large 
						mountaintop relatives.  Similarly, work has just begun 
						on low cost active secondary mirrors which can be 
						“warped” to counteract distortions in lightweight 
						primary mirrors.  Such active mirrors can also be 
						tip/tilted to reduce the effects of the wind gusts on 
						portable telescopes.  Finally—also similar to the 
						largest mountaintop telescopes—we anticipate that the 
						largest meter-class telescopes will employ multiple 
						mirrors to reduce weight and facilitate manufacture and 
						handling.
 Observational ProgramsVisual Recreational, Outreach, and 
						Educational 
						observational programs involve both recreational 
						observing for enjoyment, as well as public outreach, and 
						education.  Recreational visual astronomers are 
						interested in everything they have a chance to see, so 
						the exciting advantage of a high optical quality, one 
						person set up, one meter telescope is that there’s much 
						more to observe.  Visual observers marvel at seeing the 
						real photons from objects ranging from our solar system 
						to billions of light years away. Many are inspired by 
						the excellent astro-images being made today and want to 
						see a similar amount of detail visually. Some are 
						excited by being able to barely detect the faintest 
						possible objects such as distant galaxy clusters, 
						quasars and gravitational arcs. Other examples:
 
							
							Planetary detail in 
							saturated color.
							
							
							Hints of color in the 
							brighter emission nebulae.
							
							
							Spiral arms in 17th 
							magnitude and brighter galaxies.
							
							
							HII regions and star 
							clusters in 16th magnitude and brighter 
							galaxies.
							 
							Exotic new 
							discoveries like Hanny’s Voorwerp.
							
							
							Tidal distortions in 
							Arp peculiar galaxies.
							
							
							Seeing colors in the 
							stars that make up the brighter globular clusters.
							 
							Seeing the complex 
							internal structure of planetary nebulae, their 
							central stars, and extended halos.
							
							
							19th 
							magnitude and brighter supernovae in distant 
							galaxies.
							
							
							Digging out small 
							scale, faint details in brighter objects like 
							Herbig-Haro objects in M20.
							
							
							Soaking in the 
							glorious, exquisite details of brighter objects like 
							M51, M42, Saturn, etc… 
						
						            
						The lowest power of a high quality one meter f/3 
						Newtonian that produces a 7 mm exit pupil is 150 with a 
						field-of-view is just under 0.6 degree using a 21mm 
						Ethos eyepiece and the Paracorr 2 coma corrector. This 
						combination is large enough to see the entire Moon and 
						big chunks of larger deep sky objects such as the Veil 
						Nebula. The field of view at lowest power should be well 
						corrected to the edge and provide an aesthetically 
						pleasing image. That’s exciting enough, but the sharp 
						and detailed, high power images portable meter-class 
						telescopes are capable of producing under a dark, 
						transparent, and steady sky are their real strength and 
						appeal.  Visual observers will appreciate the 
						convenience of a comfortable Nasmyth focus viewing 
						position.Astro-Imaging
						
						can also benefit from larger apertures and portability.  As 
						suggested by Dave Rowe, a 1-meter f/3 telescope with a 
						52 mm diameter field would be marvelous instrument for 
						astrophotography. The focal length is perfectly matched 
						to the pixel size and average seeing, and the wide field 
						allows for the greatest possible (affordable) etendue, 
						for spectacular wide-field imaging. The optics for such 
						a telescope are something of a challenge.
 Scientific Research 
						programs, as is the case 
						with visual and astrophotography programs, can benefit 
						from larger apertures and the dark skies opportunities 
						that portability creates.  In 
						addition to greater program object fluxes, scintillation 
						noise decreases with telescope aperture, so meter-class 
						telescopes have superior program object signal-to-noise 
						ratios for a given integration length.
 Although the bulk of scientific observations are now 
						made with instruments, visual scientific observations 
						can still make significant contributions to the 
						advancement of our knowledge.   Some of the visual 
						observations that could benefit from portable 
						meter-class telescopes include discovery searches for 
						supernovae in not-too-faint galaxies, visual photometric 
						observations of fainter variable stars such as Miras, 
						dwarf novae (to see which stars are “up”), and 
						astrometric measurements with laser-etched astrometric 
						eyepieces of fainter double stars.
 There 
						are instances where scientific observations actually 
						require portability.  For example, the size and 
						shape (and hence albedos) of  smaller diameter 
						trans-Neptunian objects (TNOs) can be determined from 
						occultations observations as a TNO passes in front of a 
						star, casting a narrow shadow that races across the 
						Earth.  Since such narrow shadows rarely conveniently 
						pass over fixed location observatories, they must be 
						observed with portable telescopes.  With larger, 
						meter-class telescopes, many more TNO occultations can 
						be observed than would otherwise be possible.
 Telescopes can be moved to a location not 
						because of some astronomical event, but because the 
						local observing conditions are advantageous in some 
						way.  For example, near IR photometry, especially Ks 
						band, benefits from high altitudes and dry skies.  A 
						number of mountaintop observatories, blessed with good 
						roads to the summit, wouldn’t mind sharing their skies 
						with portable meter-class telescopes.
 ConclusionsWe 
						have described three basic types of portable meter-class 
						telescopes: visual observation, general purpose imaging, 
						and on-axis light bucket.  Each type has its own 
						strengths and weaknesses when it comes to the three 
						types of observational programs mentioned above (visual 
						recreational, astro-imaging, and scientific research).  
						Think different strokes for different folks.
 If one’s sole interest is visual, eyeball to 
						the eyepiece, observing, then a lightweight telescope 
						that is easy to transport, quick to assemble, simple to 
						operate and maintain, and has a fast, wide 
						field-of-view, then a visual observation telescope will 
						give you the best value.  No sense paying a premium 
						price or putting up with the complexities of high 
						precision tracking and instrument rotation needed for 
						astro-imaging.  Whether your visual observations are 
						recreational, scientific research, or both, KISS may 
						apply to you.  Although they are obviously specialized, 
						visual telescopes are currently the most numerous type 
						of portable meter-class telescopes and are likely to 
						remain so for the foreseeable future.  They are leading 
						the way into meter-class telescopeland.
 On the other hand, if one is interested in 
						both visual observing and astro-imaging, then a general 
						purpose imaging telescope may be your best choice.  
						These telescopes are also excellent scientific work 
						horses, as they can handle every sort of detector, be it 
						area (cameras) or point source (photodiodes, 
						spectrographs, etc.).  Of course for the same aperture, 
						these telescopes are more expensive than visual 
						observation telescopes.  They are just beginning to 
						appear on the market.
 If one is only interested in aperture 
						photometry, spectroscopy, or polarimetry, then an 
						on-axis light bucket telescope may give you the most 
						on-sensor photons for your dollar.  These are 
						specialized telescopes—they typically don’t even feature 
						an eyepiece!  If you main interest isn’t a specialized 
						area of scientific research, then one of the telescopes 
						is probably not for you.  These are relatively rare 
						telescopes and are likely to remain so.
 The era of portable meter-class astronomy has been 
						underway now for several decades—ever since the first 
						large aperture alt-az Dobsonian telescopes first made 
						their appearance.  Visual observations through Dobs have 
						endeared an entire generation of the public to 
						observational astronomy.  We 
						hope and expect that 
						the use of portable meter-class telescopes will 
						increasingly be extended beyond visual observation, not 
						only to recreational astro-imaging, but also to a wide 
						variety of scientific research projects.  The dark skies 
						beckon the ever increasing numbers
						of portable meter-class telescopes of all types.
 We maintain that portability doesn’t have to be 
						restricted to “smaller” apertures.  The only limits 
						should be our ingenuity and what can be legally towed 
						down the road.  There is no reason we shouldn’t see 
						portable 2 meter telescopes in the near future, starting 
						first with on-axis light buckets and then spreading to 
						visual and even general purpose imaging telescopes.  
						There will be many problems to overcome on the way to 2 
						meter portability, but we'll solve them all—one at a 
						time.
 
 Conference Organizational Specifics
 Invited 
						PowerPoint talks will be 20 minutes in length.  
						Alternatively, all attendees are welcome to display a 
						poster for the entire conference.
 Mid-morning 
						breaks will be set aside for poster discussions. Written 
						versions of selected talks from the conference will be 
						combined with other contributions to the book 
						Portable Meter-Class Astronomy, which will be published by the 
						Collins Foundation Press.
 
						Pre-conference tours are 
						being arranged for 
						Volcanoes 
						National Park (Wednesday January 18) and
						Mauna Kea Observatories 
						Thursday January 19).  Post conference tour to  will be arranged 
						if there is sufficient interest. Accompanying guests will be welcome on the tours and 
						evening functions. All attendees need to register. The modest registration 
						fee covers miscellaneous conference expenses and morning 
						refreshments.  Local 
						accommodations
						are reasonably 
						priced.  The Big Island of Hawaii is ideal for a 
						family 
						vacation. 
						Click 
						here for special information for astronomer's 
						visiting the Big Island 
						For additional Information please 
						see: 
						AltAz Initiative -
						
						http://www.AltAzInitiative.orgCanada-France-Hawaii Telescope Headquarters -
						
						www.cfht.hawaii.edu
 NASA Infrared Telescope Facility -
						
						http://irtfweb.ifa.hawaii.edu
 Gemini Telescope - 
						
						
						http://www.gemini.edu
 Mauna Kea Visitor Information Station -
						
						http://www.ifa.hawaii.edu/info/vis/
 
 
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