Astronomy Cafe – May 16, 2022

Posted by as Astro Cafe

Video transcript of meeting

  • Special General Meeting for RASC Victoria Centre – Randy Enkin
    • Have a quorum of over 25 Victoria Centre members in attendance
    • Changes to ensure our bylaws are consistent with the national bylaws and BC Society’s Act requirements
    • Call for volunteers to work on more revisions to Victoria Centre bylaws over the next few months
  • Need volunteers for Astronomy Cafe – contact Randy Enkin
    • Zoom host – recording and posting the video transcripts online
    • Meeting host – tracks and runs the meetings
  • Star parties at Observatory Hill – Lauri Roche
    • May 21, Jun 4, 18 – hybrid party in-person and online on Zoom & Youtube
      • May 21 – Early Discoveries made by the Plaskett Telescope – Jim Nemec
    • Every Saturday night after the July 1st break for the summer
    • Volunteers needed: telescopes in the parking lot, RASC welcome table, Plaskett dome tour hosts, 16″ telescope operators, other roles – contact Lauri
    • Electronically-Assisted Astronomy – start planning to use at the Star Parties in future – contact Dave Lee
  • Nanaimo Astronomy – Janeane MacGillivray
    • Astronomy From Kitt Peak – David Lee presenting at upcoming meeting
    • RASC Victoria members are welcome – send an email
  • Total Lunar Eclipse reports from members – May 15/16, 2022
    • Cloudy photos from Saanich after being skunked at Cattle Point – David Lee
    • HDR smartphone photos through eyepiece, join observations from Cosmic Generation group – Nathan Hellmen-Mestleman
    • Lunar Crater transits & mare cookies – Randy Enkin
    • Cloudy photos from Sidney – Chris Gainor
    • Observed from Brentwood Bay while raining – Lauri Roche
    • Just a glimpse from Taylor Beach in Metchosin, but spotted ISS – Bill Weir
  • Plaskett Images – Dan Posey
    • Composite image of the images over last few years 
    • Whirlpool Galaxy, Whale Galaxy, Deer Link Group NGC 7331, Fireworks Galaxy NGC 6946, M100, M63 Blackeye, NGC 3718 Arp galaxy, Hickson 44
    • Plaskett nights are for enjoyment and a reward for RASC Victoria members and volunteers
    • Review of techniques to process Plaskett image data into nice images
  • Skynews magazine – Bruce Lane
    • Review of upcoming articles
    • Please send Total Lunar Eclipse observing reports to Bruce (Editor)
  • Black Holes – Randy Enkin
    • M87 Black Hole – April 22, 2019 – Event Horizon Telescope
    • Sagittarius A* Supermassive Black Hole – May 16, 2022 – BBC Science Focus article
    • Galactic nucleus observed by Karl Jansky in 1931 – published in Nature, 173, 985-987, 1954
    • Angular resolution problem solved by the Event Horizon Telescope
    • Motion analysis of objects and energy near the Event Horizon of a black hole
    • Lauri Roche’s “black hole” birthday gift

Total Lunar Eclipse – May 15/16, 2022

Posted by as Observing Highlights

On Sunday, May 15th, 2022, we will be able to view a total eclipse of the Moon (weather permitting) from Southern Vancouver Island, British Columbia, Canada. The Moon will be in full eclipse after rising from the southeastern horizon, remaining fully eclipsed for about an hour before transitioning into a partial phase as it climbs in altitude and moves to the south. The Lunar Eclipse will end just before midnight.

Enlarge this video to view details for the Lunar Eclipse timing and phases. Depiction of this particular Lunar Eclipse is as viewed from Victoria – generated by Starry Night Pro Plus 8 and captured using Snagit 2022.

This is a perfect opportunity to visually observe this beautiful celestial event, and possibly capture some photographs from a location with an unobstructed view to the east and south.

Total Eclipse Begins8:29PM
Moon Rises8:42PM – probably visible 10-15 mins later
Greatest Eclipse9:12PM
Total Eclipse Ends9:54PM
Partial Eclipse Ends11:51PM
Above Eclipse times are for Pacific Daylight Time (PDT) for the west coast of North America, and are calculated from UT as presented in the Observers Handbook 2022, pages 127-131.
Lunar Eclipse diagram – NASA

What’s Happening

A total lunar eclipse occurs when the Earth comes between the Sun and the Moon. During a lunar eclipse the Moon’s position traverses the Earth’s shadow. The Moon’s first contact with the Earth’s shadow is at the outer band of the shadow called the penumbra. The light falling on the Moon is progressively blocked until at the moment of total eclipse the Moon is completely in the darkest central area of the Earth’s shadow called the umbra. At the point of total eclipse the process starts to reverse itself until the Moon is totally out of the Earth’s shadow.


Glossary

  • limb – the outer edge of the Moon
  • penumbra – the outer band of the Earth’s shadow
  • umbra – the darker central area of the Earth’s shadow
  • partial eclipse – the Moon is positioned within the penumbra
  • total eclipse – the Moon is positioned totally within the umbra

Observing Tips

What do you need?

Everything from your eyes, binoculars and telescope are suitable. Bear in mind this is a long process, so dress warmly and bring a chair if you want to be comfortable.

Find yourself a location that has a clear horizon view to the east and south especially if you wish to view the early fully-eclipsed stage. Observing from a hill will help you spot the rising Moon earlier than if you observe from lower elevations or sea level.

Keep a log of what you see and note the time. Pay attention to how much of the light on the moon is obscured and if there are any colouration changes. During the total eclipse the Moon will take on a deep orange-red colour. The colour of the Moon is a function of contaminants in the atmosphere and varies from year to year.

A good observing project for this long-lasting eclipse will be to observe the craters on the Moon as the eclipse progresses. Craters will be immersed and emerge from the Earth’s shadow on the Moon at times specified in the Observers Handbook 2022, page 131.

2019 Total Lunar Eclipse from Victoria – composite photo by Joe Carr

Photographic Tips

Equipment

Any camera with the capability of setting shutter speeds and aperture settings manually will do fine. The ability to use interchangeable lenses will be an advantage for more detailed images of the Moon. For the darker parts of the eclipse, eg. totality you should use a tripod support for best results. If you have access to a telescope you can try capturing the event using prime focus techniques through the telescope optics.

Settings

Today’s digital cameras are very sensitive to light reflected by the Moon. Use ISO 400 to ISO 800 and a long telephoto lens or zoom setting. Smartphones and point-and-shoot digital cameras will not produce rewarding photos of the eclipsed Moon, but can be useful for taking panoramic shots of your surroundings which include the eclipsed Moon.

Technique for smartphone cameras

Smartphone cameras typically do not support manual settings, so using them to capture a lunar eclipse will be less rewarding than using more capable cameras. That said, smartphone cameras can be held up to a telescope eyepiece to capture an image of the Moon. Aligning the tiny lens to the eyepiece can be tricky, however there are platforms made to clamp onto an eyepiece barrel which will hold smartphones steady enough to take acceptable photos of the Moon, including the eclipsed Moon.

Technique for interchangeable lens cameras

The simplest eclipse pictures can be taken with manual settings on your camera and a normal lens, preferably supported by a tripod. For best results use a cable release to minimize vibration. Images taken in this fashion result in a small lunar image. This is why it is preferable to use a telephoto lens to photograph the Moon.

For a full frame camera try a 200mm lens or even better, a 500mm lens or higher. You may also use teleconverters to increase magnification, these typically come in 1.4x and 2x strengths. Their downside is they reduce the effective aperture of your optical system. A 1.4x teleconverter will decrease your effective exposure by 1 stop, a 2x teleconverter will decrease your effective exposure by 2 stops. Work out your effective aperture of your optical system ahead of time so you don’t have to think about it on the night of the eclipse.

Note for the smaller sub-full frame sensors of some digital cameras you gain an extra advantage as the focal length of the lens is effectively magnified by a factor. For example a Nikon DX body your 200mm lens would be effectively 300mm.

  • APS-C Nikon DX, Pentax : 1.5x
  • APS-C Canon EF-S : 1.6x
  • Four Thirds : 2x

Example:

 Focal Length ApertureEffective Focal Length
with 2x teleconvertor
Effective Aperture
with 2x teleconvertor
 180mm 2.8 360mm 5.6
 480mm 6.8 960mm 13.6

To achieve any higher magnification than what is stated above you will have to use a telescope at prime focus. For this your manual camera does need to have the capability of using interchangeable lenses. For prime focus you will use the telescope optics as your interchangeable lens. To attach your camera to your telescope you will need two things a T-adapter that fits your camera and a telescope camera adapter that fits your telescope.

The telescope camera adapter is designed to fit in the focusing tube of your telescope and is threaded to accept the T-adapter of your camera. With the magnification involved with telescopic optics it is likely that you will need to use a tracking mount. Preferably the mount should be able to track at lunar speed as opposed to sidereal but if the shutter speeds chosen are shorter than 1 or 2 minutes this is not critical.

Exposure times are the next consideration. The following exposure times are based on a medium ISO setting and an effective aperture that would be common with a long telephoto and teleconverter combination. Exposures may vary with your equipment based on ISO speed and effective aperture. The Danjon Lunar Eclipse Luminosity Scale has been included to provide better guesstimates for totality.

Exposure Times: based on ISO 400
Full Moon1/500 second at f/16
1st Contact1/250 second at f/16 see note 1.
2nd Contact1 second at f/16 see note 2.
Totality
*see table below
L = 4 : 4 seconds at f16  L = 3: 15 seconds at f16  L = 2: 1 minute at f16  L = 1: 4 minutes at f16
3rd Contact1 second at f/16 see note 2.
4th Contact1/250 second at f/16 see note 1.
* Danjon Lunar Eclipse Luminosity Scale
 L = 1dark eclipse; lunar surface details distinguishable only with difficultly
 L = 2deep red or rust coloured eclipse; central part of the umbra dark but outer rim relatively bright
 L = 3brick-red eclipse; usually with a brighter (frequently yellow) rim to the umbra
 L = 4very bright copper-red or orange eclipse, with a bluish, very bright umbral rim

Note 1. 1st and 4th contact times given for the partial phases are biased for the light part of the Moon. Remember you are dealing with vastly different exposures between the light and dark parts of the Moon during eclipse. The bias of about 1 stop minus avoids overexposure of the dominant bright area of the Moon.

Note 2. 2nd and 3rd contact times given for the partial phases are biased for the dark part of the Moon. The bias of about 1 stop plus is a good strategy for negative film not quite so good for slides and digital capture given they don’t tolerate overexposure well.

The exposure times are only recommendations. Remember the cardinal rule about photography … bracket. Always try exposures plus and minus your chosen exposure. This gives you a better chance at getting usable results. Let’s all hope for clear weather. If you have any questions please send email to David Lee at davidflee7331@gmail.com.


David Lee – original text
Joe Carr – updated for 2022
Brenda Stuart – illustrations


More information:

Astronomy Cafe – May 2, 2022

Posted by as Astro Cafe

Video transcript of meeting

  • Intro – Randy Enkin
  • Astronomy Day – David Lee
    • Final check-in this Wednesday evening for leads before Saturday events
    • International Astronomy Day – May 7, 2022
  • Vancouver Island Science Fair intro to awardees – Randy Enkin
  • VI Science Fair: Light At Night – Beata Ariana-Minniti (Cedar Hill Middle School student)
    • Creating a bus stop light using natural resources
    • Parts: Thermoelectric generator, voltage regulator, LED light
    • Heat storage: sand in an insulated box
  • Canada-wide Science Fair: Lower CubeSat orbit could Protect Space Infrastructure – Nathan Hellner-Mestelman
    • CubeSats collide, creating dangerous space debris that orbits the Earth – Kessler Syndrome
    • Quantifying the collisions
    • Lowering the hazard: choosing best orbits, adding micro-thrusters to CubeSats to change orbit or de-orbit
  • Astrophotos from southern Arizona – John McDonald & Garry Sedun
    • Caldwell 30 galaxy
    • M33 Triangulum Galaxy
    • NGC 2903 barred spiral galaxy
    • IC 433 Jellyfish Nebula
  • Eclipse Crater Timing – Randy Enkin
  • James Webb Space Telescope Update – Chris Gainor
    • All onboard instruments are now in focus
    • Commissioning of instruments next, then science projects begin

Astronomy Cafe – Jan 31, 2022

Posted by as Astro Cafe

Video transcript of meeting

  • Delivery of Calendars & Handbooks – Lauri Roche & Chris Gainor
    • Delivery of RASC 2022 Calendars for Victoria Centre should happen tomorrow
    • 4 members present still don’t have their Observers Handbooks – Duane Weaver, Brock Johnston, Bill Weir
    • The last Board meeting was dedicated to getting the delivery issues resolved
  • Pastel Paintings of the planets – Nathan Hellner-Mestelman
    • Jupiter – from Juno mission image
    • Earth and the Moon from space
    • Saturn in monochrome
    • Mars – Olympus Mons and Valles Marineris juxtaposed
    • Discussion about artistic technique
  • Cordillera Mountains & Mare Oriental lunar features – Randy Enkin
  • A Lunar Alpine Quest – Reg Dunkley
    • Original presentation to Victoria Centre on Nov 6, 2017 
    • Dorothy Paul – sketch of lunar mountains from the 2017 Solar Eclipse
    • Reg took a photo of the same area at  the 2017 Solar Eclipse and measured the height of one of the mountains on the Moon and the height of the solar chromosphere
    • Identified the particular mountain using Solar Eclipse Maestro software and some trigonometry from Lunar Reconnaisance Orbiter (LRO)
    • Schluter Crater is likely the candidate for the gap in the corona imaged by Reg
    • Brock Johnston showed a photo of the partial eclipse featuring similar “bumps” in the partial eclipse line
  • Edmonton astrophotos – Dave Robinson
    • JWST telescope in a star field time lapse imaged by Anwar Abdur
    • Jan 28, 2022 text observing report from Luca Vanzella – Orion & Auriga and NGCs in Cancer, Gemini, Monoceros
  • SIG meetings – David Lee
  • James Webb Space Telescope (JWST) – Chris Gainor
  • Victoria Centre AGM – Randy Enkin
    • Monday, Feb 21st – starting at 7PM online
    • Keynote Speaker: Life and Times of the Sky Quality Meter – Doug Welch

Astronomy Cafe – Jan 17, 2022

Posted by as Astro Cafe

Transcript video of the meeting

Meeting notes

  • A Woman of Astronomy – Marji Welchframe
    • Urania, Muse of Astronomy
    • Seal of the RASC – “Quo Ducit Urania” (i.e. where Urania leads, we follow)
    • Urania is 1 of 9 Muses of the Arts in Greek Mythology
    • Uranometria star atlas by Johann Bayer (1603) – published and sold by Sky & Telescope (Willman Bell section)
  • Early computer memories
    • LGP-30 tube-based computer used at the University of Alberta in Edmonton by John McDonald in 1958
    • Reminisces from various members about early computers, calculators, slide rules, and other computing devices and programming languages they used decades ago.
  • Lunar Puzzles – Randy Enkin
    • 100-piece from NASA
    • 1000+ piece from Cobble Hill
    • 1000 piece from Four Point
    • 3-D printed Moon puzzle – Randy and his daughter assembled it
  • Reports  from Lauri Roche
    • 2022 RASC Calendars have still not arrived
    • Sky Cultures of the World: RASC World Asterisms Program – Charles Ennis, 1st VP with RASC National – FDAO Star Party – this Sat, Jan 22nd 7-9PM – available on Zoom and Youtube
    • Eclipses for 2023 and 2024 – Education & Public Outreach Committee task force headed by Randy Attwood. Thousands of eclipse glasses will be available and sent to RASC Centres. Members can participate on the committee – contact Lauri.
  • JWST Update – Chris Gainor
    • Mirror Segment Deployment Tracker – activating the actuators behind the mirror segments
    • JWST enters a halo orbit around L2 position this Sunday, Jan 23rd
  • Astro Cafe next week – Jan 24, 2022
    • Dr. Tanya Harrison, “a professional Martian” – our Astro Cafe speaker next week
    • David Lee will be hosting
  • Scarlett Caterpillar Club – a parasitic fungus Bill Weir found near the observatory at Pearson College

Extras

  • NASA 3D Resources – 3D models of equipment, models of celestial and solar system objects, space missions (like JWST). Various media for download: fly-throughs, interactive visualizations, 3D printer files, stereo images.

Astronomy Cafe – Dec 6, 2021

Posted by as Astro Cafe

Transcript video of the meeting

  • Review next week’s presentation by Dr. Robert Thirsk – Chris Purse
    • Connection to meeting will be through a waiting room
    • Jeff Pivnick will host
    • Link for this meeting will be unique, and emailed to all RASC Victoria members
    • Maximum of 100 attendees
  • Total Solar Eclipse from Antarctica – Joe Carr
  • Astro Compass – Randy Enkin & Peter Kabel
    • Frank Younger’s estate donated the Compass Astro to Victoria Centre
    • Used in aircraft when they are flying a long way north, where the magnetic field isn’t reliable
    • “It’s a sundial in reverse”
    • Need to know your position and time, sighting on a celestial object with known Right Ascension & Declination. North will be indicated accurate to within about 1º.
  • Edmonton Astrophotos – Dave Robinson
    • Photo of Comet C/2001 A1 Leonard near M3 cluster – Arnold Rivera
    • Sketch of Comet C/2001 A1 Leonard with observing narrative – Berta Beltran
    • Rosette Nebula photo – Arnold Rivera
  • Chris Gainor
    • James Web Space Telescope update
      • Completed fuelling operations for the JWST itself
      • To be mounted onto the Ariane 5 rocket next
      • Dec 22nd launch date
      • Launch website
    • Not Yet Imagined – Chris’ new book about Hubble Space Telescope’s history. Book should be available for sale in awhile through RASC’s e-store and FDAO’s e-store locally. Electronic versions from NASA
  • Comet C/2001 A1 Leonard – observing report by David Lee
    • Observed and photographed through some clear spots over the last few days
    • Poor conditions for photography, but managed to get a good wide field image of the comet using a dSLR and tracking mount
    • Virtual Telescope broadcast – tomorrow 8PM PST
  • Lauri Roche
    • 2022 RASC Calendars
      • Send any more requests for calendars to Lauri
      • Should be $16 each
    • FDAO e-store – astronomy and space themed fun items available for sale. Free local delivery or shipped by mail (extra cost).

Astronomy Cafe – May 31, 2021

Posted by as Astro Cafe

Video transcript of the meeting

  • CRD lighting of Galloping Goose Trail from Selkirk Water to Lochside/Borden and Spectrum School – Chris Purse & Dave Robinson
    • Dave has given CRD feedback – dark adaption is adequate, so opposed
    • Members should give CRD feedback through the online survey
  • Moving and installing Bill Almond’s observatory – Cameron Burton & Lisa Meister
    • Disassembly
    • Moving from Bill & Janet’s home
    • Installation at Cameron and Lisa’s home
    • Victoria Centre’s history with Bill Almond and reminisces from members
  • Total Lunar Eclipse – Randy Enkin 
    • Review of online photos (since we were clouded out)
    • Diameter of the Earth’s shadow is larger than expected – more to come
  • Edmonton photos – Dave Robinson
    • NGC 6946 Fireworks Galaxy – Tom Owen
    • Moon over Edmonton – Alister Ling
    • Sunspots – Arnold Rivera
  • Edmonton Centre’s new observatory – Dave Robinson
  • SIGs – David Lee

Total Lunar Eclipse – Jan 20, 2019

Posted by as Observing Highlights

RASC Victoria members’ photos of the 2019 Total Lunar Eclipse

On Sunday, January 20th, 2019, we will be able to view a total eclipse of the Moon (weather permitting). The Moon will be in partial phase after rising from the eastern horizon, and move into full eclipse in evening hours as it climbs in altitude and moves to the southeast. The Total Lunar Eclipse will develop over the course of about 3 hours, will be in Totality for about an hour, and will end just before midnight.

This is a perfect opportunity to visually observe this beautiful celestial event, and possibly capture some photographs from a location with an unobstructed view to the east and south.

ECLIPSE TIMELINE
Eclipse beginsMoon’s eastern limb enters the penumbra6:36 pm PST
Partial eclipse begins – 1st ContactMoon’s eastern limb enters the umbra7:33 pm PST
Total eclipse starts – 2nd ContactMoon entirely in the umbra;
deep orange red
8:41 pm PST
Totality9:12 pm PST
Total eclipse ends – 3rd Contact9:43 pm PST
Partial eclipse ends – 4th ContactMoon’s western limb leaves the umbra10:51pm PST
Eclipse endsMoon leaves the penumbra11:48 pm PST
Above Eclipse times are for Pacific Standard Time (PST) for the west coast of North America, and are calculated from UT as presented in the Observers Handbook 2019, pages 127-29.

What’s Happening

A total lunar eclipse occurs when the Earth comes between the Sun and the Moon. During a lunar eclipse the Moon’s position traverses the Earth’s shadow. The Moon’s first contact with the Earth’s shadow is at the outer band of the shadow called the penumbra. The light falling on the Moon is progressively blocked until at the moment of total eclipse the Moon is completely in the darkest central area of the Earth’s shadow called the umbra. At the point of total eclipse the process starts to reverse itself until the Moon is totally out of the Earth’s shadow.


h

Glossary

  • limb – the outer edge of the Moon
  • penumbra – the outer band of the Earth’s shadow
  • umbra – the darker central area of the Earth’s shadow
  • partial eclipse – the Moon is positioned within the penumbra
  • total eclipse – the Moon is positioned totally within the umbra

Observing Tips

What do you need?

Everything from your eyes, binoculars and telescope are suitable. Bear in mind this is a long process and at this time of year dress warmly and bring a chair if you want to be comfortable.

Find yourself a location that has a clear horizon view to the east and south especially if you wish to view during the late stages.

Keep a log of what you see and note the time. Pay attention to how much of the light on the moon is obscured and if there are any colouration changes. During the total eclipse the Moon will take on a deep orange-red colour. The colour of the Moon is a function of contaminants in the atmosphere and varies from year to year.

A good observing project for this long-lasting eclipse will be to observe the craters on the Moon as the eclipse progresses. Craters will be immersed and emerge from the Earth’s shadow on the Moon at times specified in the Observers Handbook 2019, page 129.

Totally eclipsed Moon over the Salish Sea from Cattle Point – Sep 27, 2015

Photographic Tips

Equipment

Any camera with the capability of setting shutter speeds and aperture settings manually will do fine. The ability to use interchangeable lenses will be an advantage for more detailed images of the Moon. For the darker parts of the eclipse, eg. totality you should use a tripod support for best results. If you have access to a telescope you can try capturing the event using prime focus techniques through the telescope optics.

Settings

Today’s digital cameras are very sensitive to light reflected by the Moon. Use ISO 400 to ISO 800 and a long telephoto lens or zoom setting. Smartphones and point-and-shoot digital cameras will not produce rewarding photos of the eclipsed Moon, but can be useful for taking panoramic shots of your surroundings which include the eclipsed Moon.

Technique for smartphone cameras

Smartphone cameras typically do not support manual settings, so using them to capture a lunar eclipse will be less rewarding than using more capable cameras. That said, smartphone cameras can be held up to a telescope eyepiece to capture an image of the Moon. Aligning the tiny lens to the eyepiece can be tricky, however there are platforms made to clamp onto an eyepiece barrel which will hold smartphones steady enough to take acceptable photos of the Moon, including the eclipsed Moon.

Technique for interchangeable lens cameras

The simplest eclipse pictures can be taken with manual settings on your camera and a normal lens, preferably supported by a tripod. For best results use a cable release to minimize vibration. Images taken in this fashion result in a small lunar image. This is why it is preferable to use a telephoto lens to photograph the Moon.

For a full frame camera try a 200mm lens or something close to this, even better a 500mm lens or higher. You may also use teleconverters to increase magnification, these typically come in 1.4x and 2x strengths. Their downside is they reduce the effective aperture of your optical system. A 1.4x teleconverter will decrease your effective exposure by 1 stop, a 2x teleconverter will decrease your effective exposure by 2 stops. Work out your effective aperture of your optical system ahead of time so you don’t have to think about it on the night of the eclipse.

Note for the smaller sub-full frame sensors of some digital cameras you gain an extra advantage as the focal length of the lens is effectively magnified by a factor. For example a Nikon DX body your 200mm lens would be effectively 300mm.

  • APS-C Nikon DX, Pentax : 1.5x
  • APS-C Canon EF-S : 1.6x
  • Four Thirds : 2x

Example:

 Focal Length ApertureEffective Focal Length
with 2x teleconvertor
Effective Aperture
with 2x teleconvertor
 180mm 2.8 360mm 5.6
 480mm 6.8 960mm 13.6

To achieve any higher magnification than what is stated above you will have to use a telescope at prime focus. For this your manual camera does need to have the capability of using interchangeable lenses. For prime focus you will use the telescope optics as your interchangeable lens. To attach your camera to your telescope you will need two things a T-adapter that fits your camera and a telescope camera adapter that fits your telescope.

The telescope camera adapter is designed to fit in the focusing tube of your telescope and is threaded to accept the T-adapter of your camera. With the magnification involved with telescopic optics it is likely that you will need to use a tracking mount. Preferably the mount should be able to track at lunar speed as opposed to sidereal but if the shutter speeds chosen are shorter than 1 or 2 minutes this is not critical.

Exposure times are the next consideration. The following exposure times are based on a medium ISO setting and an effective aperture that would be common with a long telephoto and teleconverter combination. Exposures may vary with your equipment based on ISO speed and effective aperture. The Danjon Lunar Eclipse Luminosity Scale has been included to provide better guesstimates for totality.

Exposure Times: based on ISO 400
Full Moon1/500 second at f/16
1st Contact1/250 second at f/16 see note 1.
2nd Contact1 second at f/16 see note 2.
Totality
*see table below
L = 4 : 4 seconds at f16  L = 3: 15 seconds at f16  L = 2: 1 minute at f16  L = 1: 4 minutes at f16
3rd Contact1 second at f/16 see note 2.
4th Contact1/250 second at f/16 see note 1.
* Danjon Lunar Eclipse Luminosity Scale
 L = 1dark eclipse; lunar surface details distinguishable only with difficultly
 L = 2deep red or rust coloured eclipse; central part of the umbra dark but outer rim relatively bright
 L = 3brick-red eclipse; usually with a brighter (frequently yellow) rim to the umbra
 L = 4very bright copper-red or orange eclipse, with a bluish, very bright umbral rim

Note 1. 1st and 4th contact times given for the partial phases are biased for the light part of the Moon. Remember you are dealing with vastly different exposures between the light and dark parts of the Moon during eclipse. The bias of about 1 stop minus avoids overexposure of the dominant bright area of the Moon.

Note 2. 2nd and 3rd contact times given for the partial phases are biased for the dark part of the Moon. The bias of about 1 stop plus is a good strategy for negative film not quite so good for slides and digital capture given they don’t tolerate overexposure well.

The exposure times are only recommendations. Remember the cardinal rule about photography … bracket. Always try exposures plus and minus your chosen exposure. This gives you a better chance at getting usable results. Let’s all hope for clear weather. If you have any questions please send email to David Lee at davidflee7331@gmail.com.


David Lee – original text
Joe Carr – updated for 2019
Brenda Stuart – illustrations


More information:

Total Lunar Eclipse – Jan 31, 2018

Posted by as Observing Highlights

Total Lunar Eclipse on Sep 27, 2015 from Victoria
Total Lunar Eclipse on Sep 27, 2015 from Victoria – photo by Joe Carr

On Wednesday, January 31st, weather willing, we will be able to view a total eclipse of the Moon. The Moon will move into full eclipse in the early hours of the morning and will be in partial phase in the western sky as the Sun rises. The Total Lunar Eclipse will develop over the course of about 3 hours. It’s a perfect opportunity to capture some snapshots of the event. Read further to find out what happens during the eclipse and how to capture it photographically.

 

 E C L I P S E   T I M E L I N E
Moon below the horizon Moon’s eastern limb enters the penumbra 2:51 am PST
Partial eclipse begins – 1st Contact Moon’s eastern limb enters the umbra 3:48 am PST
Total eclipse starts – 2nd Contact Moon entirely in the umbra;
deep orange red
4:52 am PST
Totality 5:30 am PST
Total eclipse ends – 3rd Contact 6:08 am PST
Partial eclipse ends – 4th Contact Moon’s western limb leaves the umbra 7:11 am PST
Sunrise 7:48 am PST – approximate
Eclipse ends Moon leaves the penumbra 8:09 am PST

 

What’s Happening

A total lunar eclipse occurs when the Earth comes between the Sun and the Moon. During a lunar eclipse the Moon’s position traverses the Earth’s shadow. The Moon’s first contact with the Earth’s shadow is at the outer band of the shadow called the penumbra. The light falling on the Moon is progressively blocked until at the moment of total eclipse the Moon is completely in the darkest central area of the Earth’s shadow called the umbra. At the point of total eclipse the process starts to reverse itself until the Moon is totally out of the Earth’s shadow.


Glossary

  • limb – the outer edge of the Moon
  • penumbra – the outer band of the Earth’s shadow
  • umbra – the darker central area of the Earth’s shadow
  • partial eclipse – the Moon is positioned within the penumbra
  • total eclipse – the Moon is positioned totally within the umbra
Above Eclipse times are for Pacific Standard Time (PST) for the west coast of North America, and are calculated from UT as presented in the Observers Handbook 2018, pages 126-27.

Observing Tips

What do you need?

Everything from your eyes, binoculars and telescope are suitable. Bear in mind this is a long process and at this time of year dress warmly and bring a chair if you want to be comfortable.

Find yourself a location that has a clear horizon view of the west especially if you wish to view during the late stages.

Keep a log of what you see and note the time. Pay attention to how much of the light on the moon is obscured and if there are any colouration changes. During the total eclipse the Moon will take on a deep orange-red colour. The colour of the Moon is a function of contaminants in the atmosphere and varies from year to year.


Photographic Tips

Equipment
Any camera with the capability of setting shutter speeds and aperture settings manually will do fine. The ability to use interchangeable lenses will be an advantage for more detailed images of the Moon. For the darker parts of the eclipse, eg. totality you should use a tripod support for best results. If you have access to a telescope you can try capturing the event using prime focus techniques through the telescope optics.

Settings
Today’s digital cameras are very sensitive to light reflected by the Moon. Use ISO 400 to ISO 800 and a long telephoto lens or zoom setting. Smartphones and point-and-shoot digital cameras will not produce rewarding photos of the eclipsed Moon, but can be useful for taking panoramic shots of your surroundings which include the eclipsed Moon.

Technique
The simplest eclipse pictures can be taken with manual settings on your camera and a normal lens, preferably supported by a tripod. For best results use a cable release to minimize vibration. Images taken in this fashion result in a small lunar image. This is why it is preferable to use a telephoto lens to photograph the Moon. For a 35mm camera try a 200mm lens or something close to this, even better a 500mm lens or higher. You may also use teleconvertors to increase magnification, these typically come in 1.4x and 2x strengths. Their downside is they reduce the effective aperture of your optical system. A 1.4x teleconvertor will decrease your effective exposure by 1 stop, a 2x teleconvertor will decrease your effective exposure by 2 stops. Work out your effective aperture of your optical system ahead of time so you don’t have to think about it on the night of the eclipse.

Example:

 

 Focal Length  Aperture Effective Focal Length
with 2x teleconvertor
Effective Aperture
with 2x teleconvertor
 180mm  2.8  360mm  5.6
 480mm  6.8  960mm  13.6

 

To achieve any higher magnification than what is stated above you will have to use a telescope at prime focus. For this your manual camera does need to have the capability of using interchangeable lenses. For prime focus you will use the telescope optics as your interchangeable lens. To attach your camera to your telescope you will need two things a T-adapter that fits your camera and a telescope camera adapter that fits your telescope. The telescope camera adapter is designed to fit in the focusing tube of your telescope and is threaded to accept the T-adapter of your camera. With the magnification involved with telescopic optics it is likely that you will need to use a tracking mount. Preferably the mount should be able to track at lunar speed as opposed to sidereal but if the shutter speeds chosen are shorter than 1 or 2 minutes this is not critical.

Exposure times are the next consideration. The following exposure times are based on a medium speed film and an effective aperture that would be common with a long telephoto and teleconverter combination. Exposures may vary with your equipment based on ISO speed of film used and effective aperture. The Danjon Lunar Eclipse Luminosity Scale has been included to provide better guesstimates for totality.

 

Exposure Times: based on ISO 400
Full Moon  1/250 second at f/16
1st Contact 1/125 second at f/16 see note 1.
2nd Contact 2 seconds at f/16 see note 2.
Totality
*see table below
L = 4 : 8 seconds at f16
L = 3: 30 seconds at f16
L = 2: 2 minutes at f16
L = 1: 8 minutes at f16
3rd Contact 2 seconds at f/16 see note 2.
4th Contact 1/125 second at f/16 see note 1.
* Danjon Lunar Eclipse Luminosity Scale
 L = 1 dark eclipse; lunar surface details distinguishable only with difficultly
 L = 2 deep red or rust coloured eclipse; central part of the umbra dark but outer rim relatively bright
 L = 3 brick-red eclipse; usually with a brighter (frequently yellow) rim to the umbra
 L = 4 very bright copper-red or orange eclipse, with a bluish, very bright umbral rim

 

Note 1. 1st and 4th contact times given for the partial phases are biased for the light part of the Moon. Remember you are dealing with vastly different exposures between the light and dark parts of the Moon during eclipse. The bias of about 1 stop minus avoids overexposure of the dominant bright area of the Moon.

Note 2. 2nd and 3rd contact times given for the partial phases are biased for the dark part of the Moon. The bias of about 1 stop plus is a good strategy for negative film not quite so good for slides and digital capture given they don’t tolerate overexposure well.

The exposure times are only recommendations. Remember the cardinal rule about photography … bracket. Always try exposures plus and minus your chosen exposure. This gives you a better chance at getting usable results. Let’s all hope for clear weather. If you have any questions please send email to David Lee at davidflee7331@gmail.com.


David Lee – original image and text
Joe Carr – updated for 2018
Brenda Stuart – illustrations

Total Solar Eclipse – August 21, 2017

Posted by as Observing Highlights

2012 Total Solar Eclipse aboard the Paul Gauguin cruise ship, on the totality track south of New Caledonia Nov 14, 2012 200km south of New Caledonia in the Coral Sea
2012 Total Solar Eclipse

A Total Solar Eclipse is a rare astronomical event, and it is even rarer for one to occur close to where you live. Those of us who live in the Pacific Northwest of North America will be favoured with such an event happening near us on August 21, 2017. In fact, everyone in North America is within striking distance of being able to observe this amazing event, where the Moon slides in front of the Sun for a few brief minutes, suddenly and totally obscuring the Sun.

If you haven’t observed a Total Solar Eclipse, this is your chance!

Location

The eclipse tracks across Oregon and Idaho, making it easy to get to the eclipse totality track from Victoria, British Columbia with one day’s drive. The major cities of Portland and Eugene in Oregon are obvious targets for those of us who are eclipse chasers. I-5, an Interstate highway, crosses the eclipse centreline at the city of Salem, Oregon as the eclipse tracks eastward across the U.S.A. So you might decide to stay in Portland or Eugene, but you will have to drive to the centreline, otherwise you will miss the eclipse!

NASA’s Eclipse website gives all the facts and figures required to find and enjoy the eclipse, including an interactive zoomable map showing the eclipse track.

Total Solar Eclipse 2017 track across Oregon and Idaho
Total Solar Eclipse 2017 track across Oregon and Idaho

At the intersection of I-5 and the eclipse path near Salem, Oregon, these are the characteristics of the eclipse:

Lat.: 44.803° N
Long.: 123.0318° W

Duration of Totality: 2 minutes 0 seconds

  • Start of partial eclipse (C1) : 09:05:18AM  Altitude=27.8° Azimuth=101.2°
  • Start of total eclipse (C2) : 10:17:13.0AM  Altitude=39.8°  Azimuth=116.8°
  • Maximum eclipse : 10:18:13AM  Altitude=40.0° Azimuth=117.0°
  • End of total eclipse (C3) : 10:19:13AM  Altitude=40.1° Azimuth=117.3°
  • End of partial eclipse (C4) : 11:37:50AM  Altitude=51.0° Azimuth=140.1°

Why this location? Well, if you look at the weather predictions and the track maps, you will see this location is easiest to get to from Victoria, and offers a decent chance of clear skies. Simply take a ferry to the mainland, and drive down I-5 to Oregon. This location is away from the coastal clouds, even though there is better weather available if you drive eastward through Oregon and possibly into southern Idaho. You can also seek out more scenic locales such as Wyoming, however now you will be traveling much further.

What if you can’t travel to the track of totality?

You can still see a partial solar eclipse from anywhere in North America. Use NASA’s Interactive Eclipse Map to get the calculated timing for the eclipse in the area you plan to observe from. Click and zoom to your area, then click on your observing spot to see a popup telling you how long the eclipse will last and what you will see.

Eclipse observing events in Victoria, BC, Canada – 90% coverage in Victoria

Weather map for the Total Solar Eclipse 2017 in Oregon
Weather map for the Total Solar Eclipse 2017 in Oregon

Weather

Weather always plays a big part in any solar eclipse, so being mobile is key to improving the odds of actually seeing the event should clouds threaten to obscure the Sun at the critical moment. Our very own Jay Anderson (former RASC Journal editor) is a weather expert, and specializes in forecasting weather for solar eclipses. His Eclipse website offers sage advice backed up with maps and charts depicting weather prospects for each eclipse happening in the world for the next several years. Read Jay’s analysis of the area you propose to observe from, so you understand how the weather might behave on eclipse day. Topography, elevation changes and local factors play into how the weather evolves throughout the day for a particular locale. Become a local weather expert, and you increase your chances for success!

Observing

Observing a Total Solar Eclipse is pretty easy, however that said, if you haven’t done it before, it’s nice to have experienced eclipse observers around to guide you through the process. Obviously the time of total eclipse is the main event, however other things happen beforehand, afterwards, and during an eclipse that are worthwhile.

You should try out any gear you propose to take with you before you leave. Make sure you have proper solar eclipse filters for any binoculars, camera lenses and telescopes you are bringing along. Take test photos of the Sun weeks before you leave, so you know your photo gear will work as expected. Always have a backup plan for when (not if) gear breaks, or you simply can’t get it to work properly. Remember, you only have a couple of minutes to see this event!

Finally, relax and enjoy the day. Arrive early. Try to manage your stress level. Just sit back in a reclining chair, have your solar glasses handy, and enjoy!

Safely observing a solar eclipse – read about how to safely observe a solar eclipse

DIY Box Pinhole Projector – to safely observe the eclipse with only a box and some aluminum foil!

Help!

If this will be your first time observing a total solar eclipse, no doubt you have many questions and concerns, and don’t know where to start. The resources presented here may be overwhelming. Please ask any questions you might have about eclipses at Astronomy Cafe, held each Monday evening. Your fellow RASC members have observed solar eclipses before…they can help!

Perhaps you prefer to leave it to someone else to organize for you, and take a tour. Tour organizers will ensure you are on the centreline for the event, will do their very best to seek clear skies (no guarantees though!), and will supply you with eclipse glasses and ensure you are as comfortable as possible throughout the event. Some suggestions:

  • RASC Eclipse 2017 – a scenic holiday to the midwest USA, a solar eclipse, and sponsored by RASC!
  • Sky & Telescope – overland to Nashville, seeing rockets and observatories along the way…and the eclipse
  • Travelquest – a tour company specializing in eclipses who are offering five different experiences for the 2017 eclipse

Resources

  • NASA’s Eclipse – a great starting point for information gathering and predictions
  • Eclipsophile – Jay Anderson’s weather predictions are a must to select a location that will likely have clear weather
  • Great American Eclipse – comprehensive information about this specific eclipse – where to go and what you will see
  • Eclipse 2017 – lots of home-grown advice about where to be and what to do
  • America’s 2017 Solar Eclipse – Sky & Telescope’s online resources for planning your eclipse adventure
  • MrEclipse – Fred Espenak’s guide to successfully experiencing and photographing an eclipse
  • Mr. Eclipse says west may be best… – Fred’s eclipse predictions to the Seattle Astronomical Society
  • Kendrick Astro – a Canadian astronomy dealer who sells solar filters for visual and photographic use