Totality from Casper, Wyoming

The eclipse was a perfect success! Clear skies prevailed throughout totality, with forest fire smoke and clouds coming in after it was all done. The temperature dropped from 88 to 68F, stunning! The corona was larger than those I had seen before. We had prominences and more. MANY images to deal with and not fast internet, so please be patient while I get these things edited and out there. It might take a while… a week or more. In the meantime, here are a couple of unedited shots. 

Casper was most generous: we had an excellent space from which to observe: green grassy fields on to the hill to the east of town. The parking lot lights and grass watering sprinkler systems had been disabled for the day. The medical center even provided a lunch at the end!  

Mid Corona 2017

Totality: This is the mid-corona using a longer exposure to show the fainter regions.

 

Inner corona 2017

Totality: The inner corona. Note the fain, pink solar prominences on the right limb.

 

Partial stage 2017

Partial stage as the eclipse begins. There are a few sunspot groups to see there.

 

Diamond ring 2017

The diamond ring as the eclipse reaches totality.

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A Casper Saturday: People Arrive!

The town of Casper, WY is now hopping along. A lot more people are here today. We started out with a visit to the Geology Museum on the southwest side of things. They have an excellent display on geologic time along with representative minerals and fossils from each period/era. They also have their very own T.rex skeleton, a nice surprise. It is being slowly picked out of the encasing rock….

So, there was a lot of good paleontology to enjoy there for sure!

Back into town, the place is swinging. Lots of people wandering about with geeky T-shirts… yes, these are eclipse watchers for sure. The town has closed off the central area for shops to show off their goods, for people to mill about, to have a quick bight to eat/drink, and relax in the summer sun, a hot summer sun, pushing to 90F. The skies today: crystal clear. Absolutely lovely.

 

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Safe Arrival in Casper, Wyoming

All, I am safely here at Casper, Wyoming, right on the line for the eclipse. We DID have rooms in the local motel (YAY!) and have been rambling through town a little to get oriented. The town is divided in a couple of neat ways: the Platt River runs through as does a major train route frequented by the BNSF RR and others. The town has a basic grid layout with a couple of highways to help with faster circumnavigation. It is clear, sunny and hot, and the weather is supposed to stay that way through the eclipse. Restaurants and businesses are all out in full force with eclipse gear: shirts, hats, pins, logos, stickers, drinks (ranging from soda to beer to, yes, eclipse vodka made locally). One can not make way through town without seeing some reference or another. Yesterday as we drove into town, there was little in the way of traffic, so I surmise that there will be a LOT of traffic today and tomorrow. In short: ALL is GO for eclipse 2017 here.

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Eclipse Photography Part 2: Image Scale

** Important ** For the unscaled images of the solar disk, click on the images to display them in full size. 

** IMPORTANT!! ** All images in this post were taken through a professional solar filter. DO NOT image the sun without proper filtration!!! You could suffer permanent vision damage. Your camera will also suffer burns. 

Image scale is an interesting topic. When photographing a solar eclipse, we want to capture the details most interesting to the observer. Some will want to get wide field images of the corona. Others will want to get the inner corona and perhaps prominences. Others will want to capture images that provide a view of the eclipsed Sun with the surrounding star field. Yes, stars are visible during eclipses, and the 21st August 2017 eclipse gives us a remarkable show with the star, Regulus, within the field of view! 

This article gives three examples of image scale to consider. All images were taken with the same camera body, a Nikon D810a in full frame, FX, mode using 36.3 megapixels in raw mode. The full frame images were reduced to better fit the page here, so have been reduced to 20% of the original.  These shots allow you to see the scale of the solar disk with regards to the full scale frame out to the edges. Following each of those images is a cropped section of the original image, unscaled, so left at 100% scale, of the Sun’s disk. Be sure to click on them to see their full size.  Three lenses were used: 200mm, 300mm, and 500mm telephotos, all FX.  All images were shot through a Baader Solar Film filter covering the lens’ objective. 

200mm:

The 200mm lens is a good choice for wide field shots of the Sun and surrounding field of view (thinking of seeing the star field), and the outer edges of the faint corona. The full image is 7360 x 4912 pixels. The Sun is just over 390 pixels in diameter at this scale. This means the image is about 19 solar diameters across and 12.6 solar diameters in height.

Sun 200mm FX

The Sun taken with 200mm telephoto, full frame (FX), Nikon D810a. Resized to 20% of original.

The Sun 200mm FX cropped

The Sun taken with 200mm telephoto, cropped frame (FX), Nikon D810a. Not resized: this is full scale.

300mm

The 300mm lens is a good choice for the outer and inner corona as well as shots of any prominences, Baily’s Beads, and the diamond ring effect. This is a good all around lens for a lot of other photography as well (birding and the like). This is also a light weight lens, so travels well, attaches to tripods well without shaking, and yet takes good images for eclipses. The full image is 7360 x 4912 pixels. The Sun is about 545 pixels in diameter at this scale. This means the image is about 13.5 solar diameters across and 9 solar diameters in height.

The Sun 300mm FX

The Sun taken with 300mm telephoto, full frame (FX), Nikon D810a. Resized to 20% of original.

The Sun 300mm FX cropped

The Sun taken with 300mm telephoto, cropped frame (FX), Nikon D810a. Not resized: this is full scale.

500mm

The 500mm gives us a little more magnification, offering the great views of the inner corona, prominences and such. It is heavy, and pushes tripods to their limit unless you get a beefy one. The larger lens profile also catches wind more easily, so might present issues with shaking on a windy day. Wind tends to die down during the totality, though… a good thing. The full image is 7360 x 4912 pixels. The Sun is just about 920 pixels in diameter at this scale. This means the image is about 8 solar diameters across and 5.3 solar diameters in height.

The Sun 500mm FX

The Sun taken with 500mm telephoto, full frame (FX), Nikon D810a. Resized to 20% of original.

The Sun 500mm FX cropped

The Sun taken with 500mm telephoto, cropped frame (FX), Nikon D810a. Not resized: this is full scale.

500mm FX full scale sunspots

Sunspots visible on the Sun’s limb. Taken with 500mm telephoto full frame FX D810a. Unscaled.

 

 

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Eclipse Photography – Some Notes for the August Event!

Eclipses are exciting whether they be partial, total or annular. On August 21st of this year, the USA will have an awesome opportunity to see a total solar eclipse pass right across the entire country from Oregon to South Carolina.  People have already got their hotel rooms reserved, rental cars spoken for, and plane tickets purchased. Wherever you choose to go, you are likely to wonder about capturing this event by camera. Here are some thoughts, in no particular order (but I will try to keep it logical).

Never seen an eclipse before?  You might want to consider NOT trying to photograph the eclipse at all!  Sit back and enjoy the event. Total solar eclipses are short in duration, totality, that is. At the location of greatest totality duration (Southeast of St. Louis, MO), the totality lasts only 2m 40.2s… that is just almost about 3 minutes in length. You really want to be looking up at the corona at that point and making all sorts of exclamations!

Determined? You really want to capture this with a camera? Ok! Read on!

Initial Words of Wisdom:

Start planning NOW. Obtain your gear as soon as possible. This accomplishes two things: You will have the better choice of gear with sufficient lead time. Closer to the event, gear will be more difficult to buy. Also, you will have time to do this next important thing: Practice with your gear now!  Learn your camera, inside and out. You want to know ALL there is to know about the equipment you plan to use. Be able to use it without manuals! You WILL NOT have time during totality to learn new things about your gear. Play. Try solar photography on every clear day. Learn what works for you and your equipment now.

Wide Field Photography:

Some of the coolest looking eclipse shots are wide field images taken with fisheye lenses or wide field lenses to capture scenery and the eclipse at the same time. You can even set it up to take images every couple of minutes throughout the whole event and get a lovely series.

A video camera set to wide-field and left attached to a tripod will capture the whole event automatically, and will include sounds of the celebrations around you. Aim, turn on, record. Done. A steady tripod is handy. You might also tape a sign onto the tripod stating “do not disturb”. Check out this video from observers in Queensland for their last total solar eclipse. 

Total Solar Eclipse from Queensland Australia

Individual shots: a DSLR or point and shoot camera should be on a tripod. You can take images at short exposure lengths 1/500s or faster depending on your ISO. This will capture the day-lit scenery and the sun. If the camera is well mounted, be sure to aim the middle of your eclipse series towards the center of the frame. Below is a typical wide field setup: a DSLR with 16mm fisheye on a stable tripod. Note that many new DSLRs also have the capability to shoot video <hint hint>.

Wide field imaging setup.

A Nikon D7000 with 16mm fisheye lens for wide field photography. This will capture good images of the surrounding scenery and the eclipse at the same time. No need for a solar filter here. The tripod keeps it all stable.

Below is an image taken with a Nikon D810 at 100 ISO f/8 for 1/640 second exposure. It was resting on a tripod and released manually (i.e. finger on the shutter release button). Shorter exposure times will show less of the scenery, but might show the sun and the corona a little more clearly.

Fisheye image of sun at noon.

This image taken with the setup seen in the photo above, a D7000 ISO100 1/640s f/8 on tripod with 16mm fisheye.

If you have manual focus: set it to manual and focus it onto a distant object and then leave it there. Also, set the ISO, shutter speed and f-stops (aperture) and leave it on manual mode. You will then see the surroundings get darker at totality instead of having the camera keep trying to take properly exposed shots in the darkness of totality.

Many cameras have built in interval timers. Set it up, start the sequence and go enjoy looking at the eclipse!

Telephoto/Telescope:

This gets a little trickier. First and foremost a WARNING: YOU NEED A SOLAR FILTER for your camera and your eyes! DO NOT MESS AROUND HERE. The sun will cause irreversible harm to your eyes if you look at it. It will do more harm more rapidly if you use a telephoto lens without proper filtration!  Got it?!  Good!  This is really important!!!  

Appropriate filters are those made for solar observing and DO NOT include welder’s glass, exposed film negatives, sunglasses, and similar. Good filter material:  Baader Solar Film. You can buy a lot and make a ton of filters for your cameras and friends’ as well.  Buy it NOW or you will find it much more difficult to get closer to eclipse date.

You can buy Baader Solar Film on Amazon.com.

A filter should be placed in front of your lens until just the second before totality. This protects you and the camera and the lens. You can then watch the eclipse as it progresses. I recommend taping the filter onto the lens hood to protect it from being blown off by wind and to prevent interested people from trying to remove it. That is a no no.  Throughout totality and into the moment when Bailey’s Beads are visible, you can take the filter off and shoot without it.

Experiment with your setup and filters well in advance of the eclipse date. Practice using your camera to take solar images. Do this often. Get to know your camera inside and out. Be able to operate it manually without any guide book.

Eclipse imaging setup.

The telephoto setup: a D200 with 300mm telephoto. There is a Baader solar film filter on the front. A right angle viewfinder is attached. This was a windy day! The sturdy tripod helped a lot.

Tripod: You need one with telephoto lenses.  You need a sturdy one.  The sturdier, the better. For a 300mm lens on a full frame (FX) camera, I use a Manfrotto MT055XPRO3 055 Aluminium 3-Section Tripod with Horizontal Column.  There is also the issue of the tripod head. I use one with slow motion controls, also a Manfrotto item: Manfrotto 405 Pro Digital Geared Head. These are not inexpensive items! Whatever you use, the ability to slowly move the pointing as the earth rotates is very helpful. It just has to be stable as a rock.

A word about tracking: Some of you will be tempted to go find an astronomical tracking mount for this event… thinking that you can mount the camera onto the mount and just let the thing track through the event automatically. If you have not done this before, avoid the temptation. A good tracking mount is much more expensive, as it has to be massive to hold your lens and camera combination. Alignment with the earth’s rotational north pole is not easy in daytime. You will need batteries or another power source to drive it. Just no. It is EASY to manually track the sun in a camera’s viewfinder. Keep it simple. Travel lighter. Save money. If you’re a pro and plan on doing this, then you already know what you are up against. No need to discuss this any more.

Lens:  A DSLR and a telephoto from 300mm up will be great. 300-400mm lenses are more than adequate for some excellent photography…. There is no need for a massive telescope with 8” open aperture and 1200mm of focal length. The sun is bright. The sun is also large at some 0.5 angular degree in diameter. If you use a zoom lens, be sure that you can lock the zoom feature. Use duct tape if it does not have a locking feature. Some of them will zoom in or out on their own due to gravity! Not fun if you are trying to keep things equal throughout the event.

Here is an image taken through a 300mm telephoto using a Baader solar film filter. It has been cropped but kept at 100% scale from the camera:

Partial eclipse image

Partial phase of the 1 August 2008 eclipse seen from Novosibirsk, Russian Federation. Nikon D200 and 300mm telephoto, iso1000 1/5000s f/7.1

Camera: The camera will be better if it has manual controls and manual focus. Having a remote shutter release is good in that it will reduce vibrations. Setting focus: With the solar filter on, focus on the edge (limb) of the sun until it is crystal/razor sharp. You might even have a couple sunspots to focus on. Most camera’s autofocus systems will do this nicely. Once focused, switch the camera and lens to manual focus and DO NOT touch it throughout the event. If your camera has mirror lockup mode, you can use that if you wish to reduce more vibration, but you will have to look through the viewfinder occasionally to center the sun, and that requires a mirror.  I never bothered with the mirror lockup feature for eclipses, and my images were fine.  Why setting to manual? You should expect to change the shutter speed and maybe even the aperture throughout the eclipse in order to get best exposures. The moon covering the sun will dim the event, little by little. As totality is reached, you will want to try to capture the inner corona and flares/prominences with short exposures… and then use longer exposures to capture the outer corona, requiring longer exposures. You will be VERY busy at totality.

Large zoom lens setup.

A Nikon D810a with 200-500mm zoom, right angle finder and home made Baader film solar filter. This is the limit for the tripod before things get too shaky. Add a GPS receiver and remote shutter control, and this is a perfect setup.

Working end of D810a and zoom.

The working end of the D810a and massive zoom lens. The right angle finder allows one to be looking away from the sun while taking photos. Add the shade of a rimmed hat and the extended cardboard from the filter assembly, and taking solar photos is a snap!

File Types: Most modern DSLRs, and digital cameras in general, allow one to select various modes of shooting: High, Medium, Low resolution, Raw, NEF, etc. My recommendation is to have your camera shoot both high resolution Raw images and JPGs as well.  Depending on your camera make/model, this will result in raw images of type NEF, RAW, or CRW and also store JPGs. These raw images can be edited much more cleanly than JPGs. Images will be large! Have memory to handle this. My last eclipse trip saw 350 images in all from eclipse start to finish. Also turn off any compression modes and image processing (sharpening, etc) that cameras are likely to do. Set your camera’s time and date as accurately as you can using Universal Time. If you have a GPS attached, then this will be taken care of for you. 

Totality: Much has already been written about what you can expect to see during totality. You have to decide what you are going to do, and in what priority. Some will want to just look up and enjoy. Others will want to take as many photos as possible. Assuming you are going to take as many photos as possible, read on.

  • Right before totality, you have the option to remove the filter and try to capture Bailey’s Beads. With the camera on high-speed multiple exposures, take as many images as you can, as fast as you can. You can also get the Diamond Ring Effect if your timing is good. Another option here: try to get both the beads and the ring effect at the END of totality. It happens on both sides!  
  • Remove the filter!
  • Take many photos at many different exposure times. Long exposures will show the outer and fainter corona. Shorter exposures will show the brighter inner corona and prominences. If you take a series of images with a wide range of exposure values, then you can combine them using high dynamic range software to get some amazing imagery. 
Inner corona image

A short exposure of the 1-Aug-2008 eclipse. Note the small red prominences and just a hint of the corona. The human eye will see more corona than this photo shows. Nikon D200 300mm iso1000 1/6400s f/7.1 

Outer corona image.

Long exposure photo of the same eclipse showing the fainter outer corona. Nikon D200 300mm iso1000 1/160s f/7.1

Gadgets: Below listed are some helpful things to have around. Not all are necessary. Take what you think would be helpful.  

  • A good watch.
  • GPS receiver/geotagger attached to the camera: these can log your position and the time onto each image you take. Great if you are doing science or working with the Mega-Movie-Photo-Team.
  • A right angle viewfinder for the camera: this is really helpful, as it allows to look down into the camera viewfinder instead of at the same line as the sun. Combined with a brimmed hat, this is a really nice gadget to have. Some also have 2x magnifiers which help with focusing.
  • Batteries: for all your goodies like the camera, GPS, cell phone, etc. A Charger is also handy. You are not too likely to need to change freshly charged batteries in the middle of the eclipse unless your camera loves to eat them up :-/ 
  • Extra Memory Cards for the camera.
  • Compass: not all that helpful, but just in case you need to find south…
  • Pencils and pens and notebook.
  • Maps: in case you need to avoid weather, having a paper map of the area is helpful.
  • Bug spray: sometimes bugs can really bug you!  Mosquitoes will come out in at totality.
  • Sunscreen: yep – sun burns are no fun.
  • A brimmed hat: this helps to block sun from your seeing the camera’s field of view properly.
  • A vest with a ton of pockets: to hold tools, parts, lenses.
  • A pocket knife (Swiss Army style with tools): handy to attach tripod screws to camera and many other things.
  • Duct tape: there is always a need for duct tape.
  • Plastic bags: to cover camera and gear against rain and dust.
  • Water and food: keep yourself energized and hydrated.
  • Microfiber cloth and lens dust-off-bulb: helps to clean the optics and the viewfinder window.
  • Your glasses and or contact lenses. Have an extra set.
  • Solar eclipse glasses. These are fun and allow you to see the eclipse with the unaided eye while it is in the partial phase.
  • An odd one: Permission to be where you are located!  Be mindful that it will be easy for you to be tempted to trespass onto lands for which you do not have permission! In case you do venture onto unknown property, bring photo ID with you. 

Links to other helpful sites:

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