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  • Painful Drupal 7 Migration | astrofoto.org
    the content but the structure But no it doesn t I actually set up a test site and migrated into that rebuilt all the menus book hierarchies blocks everything Then I tried to do a Drupal 7 to Drupal 7 migration It didn t do any better Blech Roland Roberts s blog Log in to post comments Printer friendly version PDF version Navigation Calendar Gallery Constellations Messier Objects M27 The Dumbell Nebula Resources Astronomy Books Buying A Star Buying A Telescope Clubs and Organizations General Interest Imaging and Astrophotography Magazines Mailing Lists and News Groups Science Toy Suppliers Software Weather Information Tips and Tricks Roland s Corner Recent content About Copyright Search form Search User login Username Password Request new password Science Daily Mercury Mercury gets a meteoroid shower from Comet Encke Mercury gets a meteoroid shower from Comet Encke More Science Daily Venus The aliens are silent because they re dead The aliens are silent because they re dead More Science Daily Mars Antarctic fungi survive Martian conditions on the International Space Station Antarctic fungi survive Martian conditions on the International Space Station Rotation speed may be bad news for Red Planet pioneers Rotation speed may be bad news for Red Planet pioneers The aliens are silent because they re dead More Science Daily Jupiter New study challenges Jupiter s role as planetary shield protecting Earth from comet impacts New study challenges Jupiter s role as planetary shield protecting Earth from comet impacts NASA telescopes detect Jupiter like storm on small star NASA telescopes detect Jupiter like storm on small star Simulating the jet streams and anticyclones of Jupiter and Saturn More Science Daily Saturn Cassini completes final close Enceladus flyby Cassini completes final close Enceladus flyby How water escapes from Saturn Magnetic reconnection How water escapes from Saturn Magnetic reconnection Explosive energy in Saturn s magnetic bubble More Science Daily Neptune Evidence of a real ninth planet discovered Evidence of a real ninth planet discovered Mars to lose its largest moon Phobos but gain a ring Mars to lose its largest moon Phobos but gain a ring Simulation of 3 D exotic clouds on an exoplanet More Science Daily Uranus Jupiter bumped giant planet from our solar system This solar system isn t big enough for the both of us Jupiter More Science Daily Pluto Earth like planets have Earth like interiors Earth like planets have Earth like interiors Evidence of a real ninth planet discovered Evidence of a real ninth planet discovered New Horizons returns first of the best images of Pluto More Science Daily Comets and Asteroids Earth like planets have Earth like interiors Earth like planets have Earth like interiors Artistic space odyssey to broadcast people s messages to the stars Artistic space odyssey to broadcast people s messages to the stars New study challenges Jupiter s role as planetary shield protecting Earth from comet impacts More Science Daily Kuiper Belt Earth like planets have Earth like interiors Earth like planets have Earth like interiors

    Original URL path: http://www.astrofoto.org/node/1436?destination=node/1436 (2016-02-13)
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  • M27: The Dumbell Nebula, Take 2
    is from an urban light polluted sky here in Brooklyn There are some problems although the image was calibrated with darks and flats it looks like I have a few dead pixels so you have that odd black spot on the left side of the nebula If you look really close you ll see a few more in the shadows Some of this may just be that the camera is not thermally controlled so a pixel that s particularly sensitive to temperature changes results in systematic miscalibration is there is thermal drift during the imaging session There was darks were taken quite late or rather early near sunrise Still overall I m pretty happy with the above It s way better than my earlier attempt from several years ago which you can see here 2 M27 The Dumbell Nebula Log in 3 to post comments 4 M27 lies in the small constellation of Vulpecula the little fox It is a large bright nebula easily seen in binoculars from a moderately dark site even from suburbia From within the metropolitan New York City area you will need a small to moderate sized telescope depending on exactly where you live This is easily found in my 8 inch f 6 Newtonian and is detectably in smaller scopes even here The view here is very minimalistic for two reasons First it s all I have since the imaging session when I took this was really a shake down period for the equipment and things did not go very well So the amount of data I have simply won t support a high resolution image Second I wanted to produce something that approximated the visual impression in a modest sized telescope While my 8 inch Dobsonian is not large it s also not really

    Original URL path: http://www.astrofoto.org/print/book/export/html/1435 (2016-02-13)
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  • TCPDF ERROR Image Unable to get the size of the image file home3 astrofot public html g2 d 17397 2 20060807 M27 jpg g2 GALLERYSID 14565ae688b5545a0cd642ef14100ccc 20alt

    Original URL path: http://www.astrofoto.org/printpdf/book/export/html/1435 (2016-02-13)
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  • M27: The Dumbell Nebula, Take 2 | astrofoto.org
    than my earlier attempt from several years ago which you can see here M27 The Dumbell Nebula Messier Objects up M27 The Dumbell Nebula Printer friendly version Log in to post comments PDF version Navigation Calendar Gallery Constellations Messier Objects M27 The Dumbell Nebula Resources Astronomy Books Buying A Star Buying A Telescope Clubs and Organizations General Interest Imaging and Astrophotography Magazines Mailing Lists and News Groups Science Toy Suppliers Software Weather Information Tips and Tricks Roland s Corner Recent content About Copyright Search form Search User login Username Password Request new password Science Daily Mercury Mercury gets a meteoroid shower from Comet Encke Mercury gets a meteoroid shower from Comet Encke More Science Daily Venus The aliens are silent because they re dead The aliens are silent because they re dead More Science Daily Mars Antarctic fungi survive Martian conditions on the International Space Station Antarctic fungi survive Martian conditions on the International Space Station Rotation speed may be bad news for Red Planet pioneers Rotation speed may be bad news for Red Planet pioneers The aliens are silent because they re dead More Science Daily Jupiter New study challenges Jupiter s role as planetary shield protecting Earth from comet impacts New study challenges Jupiter s role as planetary shield protecting Earth from comet impacts NASA telescopes detect Jupiter like storm on small star NASA telescopes detect Jupiter like storm on small star Simulating the jet streams and anticyclones of Jupiter and Saturn More Science Daily Saturn Cassini completes final close Enceladus flyby Cassini completes final close Enceladus flyby How water escapes from Saturn Magnetic reconnection How water escapes from Saturn Magnetic reconnection Explosive energy in Saturn s magnetic bubble More Science Daily Neptune Evidence of a real ninth planet discovered Evidence of a real ninth planet discovered Mars to lose its largest moon Phobos but gain a ring Mars to lose its largest moon Phobos but gain a ring Simulation of 3 D exotic clouds on an exoplanet More Science Daily Uranus Jupiter bumped giant planet from our solar system This solar system isn t big enough for the both of us Jupiter More Science Daily Pluto Earth like planets have Earth like interiors Earth like planets have Earth like interiors Evidence of a real ninth planet discovered Evidence of a real ninth planet discovered New Horizons returns first of the best images of Pluto More Science Daily Comets and Asteroids Earth like planets have Earth like interiors Earth like planets have Earth like interiors Artistic space odyssey to broadcast people s messages to the stars Artistic space odyssey to broadcast people s messages to the stars New study challenges Jupiter s role as planetary shield protecting Earth from comet impacts More Science Daily Kuiper Belt Earth like planets have Earth like interiors Earth like planets have Earth like interiors Evidence of a real ninth planet discovered Evidence of a real ninth planet discovered New Horizons returns first of the best images of Pluto More Astronomy News NASA

    Original URL path: http://www.astrofoto.org/node/1435?destination=node/1435 (2016-02-13)
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  • Preliminary Testing of Focal Reducers and the Mighty Mini for Occulation Timing
    reducer 5mm short of the ideal spacing It s worth noting that ideal here means the working distance that produces the actual 0 5x reduction factor Putting it a little closer does three things First it insures there is no vignetting by the reducer mounting Second it gives us a little wider field of view in that off axis rays would be the first to be vignetted having the reducer closer to the focal plane means the original light cone will have had more room converge so that vignetting will also be reduced Third it changes the reduction factor Measuring the OWL Focal Reducer Focal Length I recently had a chance to measure the focal length of the Tasco 50mm binocular objective for which this system was nominally optimized Ideally I should simply have some focuser system and then I can adjust the spacing and measure or even better take and image and do a plate fit to get the image scale What I actually was able to do is put in various combination of spacers and adapters to see where I get my best focus Since I don t have a wide range of spacers I m stuck with limited combinations In a few cases I attempted unscrewing an adapter by 1mm but that comes with issues rated to tilting the focal plane The whole assembly tends to droop a little when things are not screwed down tight which means the image shifts and I m measuring off axis focus which will naturally be a little worse I have the following spacers and adapters available 0 65 C to 1 25 adapter 16 5mm 1 C to 1 25 adapter 24 5mm 5mm C to Cs adapter 0 5 long 1 25 extender 12 5mm 1 5 long 1 25 extender 38 1mm The best focus came was when using th 1 C to 1 25 adapter plus th 1 5 extender two 0 5 adapters for a total of 62 6mm spacing from the back flange of the focal reducer to the camera flange The C mount flange to focal plane distance is another 12 5mm giving a total of 74 6mm plus whatever spacing there is from the back flange of the OWL focal reducer to the optical center Some crude measurements indicate the spacing to the geometric center of the lens is probably 3mm It s a crude measurement but I think we re safe in assuming the nominal 76mm FL for the OWL reducer is correct actually we know the OWL reducer is 76mm the question is whether or not the reducer bought off eBay is the real deal the answer is probably yes Measuring the Focal Length of the Tasco 50mm Binocular Objective To do this I kept attaching extender tubes to the nosepiece of a Meade DSI Pro II until I could achieve focus when the whole thing was attached to the back of the Mighty Mini in place of the PC164 EX2

    Original URL path: http://www.astrofoto.org/print/1434 (2016-02-13)
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  • Preliminary Testing of Focal Reducers and the Mighty Mini for Occulation Timing | astrofoto.org
    adapters for a total of 62 6mm spacing from the back flange of the focal reducer to the camera flange The C mount flange to focal plane distance is another 12 5mm giving a total of 74 6mm plus whatever spacing there is from the back flange of the OWL focal reducer to the optical center Some crude measurements indicate the spacing to the geometric center of the lens is probably 3mm It s a crude measurement but I think we re safe in assuming the nominal 76mm FL for the OWL reducer is correct actually we know the OWL reducer is 76mm the question is whether or not the reducer bought off eBay is the real deal the answer is probably yes Measuring the Focal Length of the Tasco 50mm Binocular Objective To do this I kept attaching extender tubes to the nosepiece of a Meade DSI Pro II until I could achieve focus when the whole thing was attached to the back of the Mighty Mini in place of the PC164 EX2 I strapped the binocular objective onto an Alt Az mount and pointed the whole thing at Polaris then took a 20 second exposure and used MaximDL 6 to do a plate fit This gave a focal length of 184mm I ve done the same thing with the Orion 9x50 objective and got 183mm So for all practical purposes these two are identical I d say using one or the other has no significant performance benefit but the Tasco is clearly cheaper This gives an effective f number of 3 66 183mm 50mm At that focal ratio the 2nd Airy disk minimum has a diameter of 4 1μm for 500nm green light 2 23 λF D In his analysis Hristro Pavlov mentions he believes the PC164 EX2 uses the Sony ICX419ALL chip which has 8 6μm x 8 3μm pixels so we re already good in putting all of the light from a star into a single pixel maximizing our sensitivity Assuming we re diffraction limited which is questionable based on some other tests Use of the focal reducer for these finders doesn t do anything to improve the sensitivity of the camera instead it increases the field of view making it easier to point them adequately Remember the field of view is more than 2 4 x3 2 with the reducer and you re trying to point blindly no finder no telrad no anything to point accurately It s the increase field of view which is the big win Footnotes This was done using the image object distance measurements I focused a room light onto a wall using the focal reducer and measured the distance from the focal reducer lens center to the wall at 101mm The distance from the wall to the light was 1968mm give or take a few so the distance to the light from the lens was 1867 This gives begin eqnarray 1 over f 1 over l 1 over l 1

    Original URL path: http://www.astrofoto.org/node/1434?destination=node/1434 (2016-02-13)
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  • IOTA | astrofoto.org
    study challenges Jupiter s role as planetary shield protecting Earth from comet impacts New study challenges Jupiter s role as planetary shield protecting Earth from comet impacts NASA telescopes detect Jupiter like storm on small star NASA telescopes detect Jupiter like storm on small star Simulating the jet streams and anticyclones of Jupiter and Saturn More Science Daily Saturn Cassini completes final close Enceladus flyby Cassini completes final close Enceladus flyby How water escapes from Saturn Magnetic reconnection How water escapes from Saturn Magnetic reconnection Explosive energy in Saturn s magnetic bubble More Science Daily Neptune Evidence of a real ninth planet discovered Evidence of a real ninth planet discovered Mars to lose its largest moon Phobos but gain a ring Mars to lose its largest moon Phobos but gain a ring Simulation of 3 D exotic clouds on an exoplanet More Science Daily Uranus Jupiter bumped giant planet from our solar system This solar system isn t big enough for the both of us Jupiter More Science Daily Pluto Earth like planets have Earth like interiors Earth like planets have Earth like interiors Evidence of a real ninth planet discovered Evidence of a real ninth planet discovered New Horizons returns first of the best images of Pluto More Science Daily Comets and Asteroids Earth like planets have Earth like interiors Earth like planets have Earth like interiors Artistic space odyssey to broadcast people s messages to the stars Artistic space odyssey to broadcast people s messages to the stars New study challenges Jupiter s role as planetary shield protecting Earth from comet impacts More Science Daily Kuiper Belt Earth like planets have Earth like interiors Earth like planets have Earth like interiors Evidence of a real ninth planet discovered Evidence of a real ninth planet discovered New Horizons returns

    Original URL path: http://www.astrofoto.org/taxonomy/term/21?destination=taxonomy/term/21 (2016-02-13)
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  • Mighty Mini | astrofoto.org
    New study challenges Jupiter s role as planetary shield protecting Earth from comet impacts New study challenges Jupiter s role as planetary shield protecting Earth from comet impacts NASA telescopes detect Jupiter like storm on small star NASA telescopes detect Jupiter like storm on small star Simulating the jet streams and anticyclones of Jupiter and Saturn More Science Daily Saturn Cassini completes final close Enceladus flyby Cassini completes final close Enceladus flyby How water escapes from Saturn Magnetic reconnection How water escapes from Saturn Magnetic reconnection Explosive energy in Saturn s magnetic bubble More Science Daily Neptune Evidence of a real ninth planet discovered Evidence of a real ninth planet discovered Mars to lose its largest moon Phobos but gain a ring Mars to lose its largest moon Phobos but gain a ring Simulation of 3 D exotic clouds on an exoplanet More Science Daily Uranus Jupiter bumped giant planet from our solar system This solar system isn t big enough for the both of us Jupiter More Science Daily Pluto Earth like planets have Earth like interiors Earth like planets have Earth like interiors Evidence of a real ninth planet discovered Evidence of a real ninth planet discovered New Horizons returns first of the best images of Pluto More Science Daily Comets and Asteroids Earth like planets have Earth like interiors Earth like planets have Earth like interiors Artistic space odyssey to broadcast people s messages to the stars Artistic space odyssey to broadcast people s messages to the stars New study challenges Jupiter s role as planetary shield protecting Earth from comet impacts More Science Daily Kuiper Belt Earth like planets have Earth like interiors Earth like planets have Earth like interiors Evidence of a real ninth planet discovered Evidence of a real ninth planet discovered New Horizons

    Original URL path: http://www.astrofoto.org/taxonomy/term/22?destination=taxonomy/term/22 (2016-02-13)
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