Q: Has Anyone Used the Simple Clip-On Lenses with Cell Phones to Try to Image Totality?
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Q: Has anyone used the simple clip-on lenses with cell phones to try to image totality?
A: Sorry, but I don’t know. Try it on the Moon some night and see how it works.
Q: I plan to photograph the eclipse through an 80-mm refracting telescope with a focal length of 600 mm. Do you recommend photographing using prime focus or eyepiece projection?
A: I recommend using prime focus. But be aware that you'll need at least two adapter rings to do this: (1) T-ring for your particular camera brand (Canon, Nikon, etc.), and (2) telescope adapter from T-ring to your telescope focusing tube.
Q: Is there any particular reason why you don't recommend a Newtonian reflector?
A: A Newtonian reflector certainly could be used, but it’s probably overkill: too big and too long a focal length. That is, unless you have a short focal length (under 1,000 mm) telescope.
Q: Would you please comment on the pros and cons of video vs. DSLR? Or maybe video with a DSLR?
A: Stills will give you higher resolution than video. But what is more important to you? Do you want the best quality still for enlargements or do you want to capture action and sound with video?
Q: What percentage of light does a solar filter pass (if I were comparing it to standard neutral density filters for photography/film)?
A: Solar filters typically have a density of 5. The means they only transmit 1 part in 10 to the power of 5 (1 part in 100,000), which equals 0.00001. For comparison, an 8x neutral density filter transmits 1 part in 8 or 0.125.
Q: Can you use a deep red filter with a white light filter such as the Baader to enhance surface texture and prominences on the sun?
A: No, you wouldn't use both of these at the same time. The red filter won't enhance any solar features.
Q: Photographing from Tennessee through an 89-mm Questar with a Questar full-aperture solar filter. During the diamond ring effect and totality, should I remove the solar filter in order to capture the corona?
A: Absolutely remove the solar filter for the diamond ring, totality, and the corona!
Q: Would a 500-mm mirror lens be better than a 400-mm lens with a 2x multiplier?
A: It all depends on the quality of these lenses and the 2x. Remember that the longer focal length of the 400-mm + 2x must also be mounted on something VERY stable or else shutter vibrations will blur the photos.
Q: I have a Thousand Oaks Optical solar filter for my Nikon 80–400-mm lens. However, the filter and the lens shade cannot simultaneously be placed on the lens. Do I need the lens shade? A: No, you don't need the lens shade during the eclipse (I don't use one either).
Q: Do you keep the solar filter on during the diamond ring effect?
A: No, I take the solar filter off at least 15 seconds before totality and then shoot a burst to capture the diamond ring. Just remember that you must not look though the camera while doing this because it's not safe for your eyes.
Q: What is the camera setting of this photo?
A: Sorry, but I’m not sure what photo was up when you entered the question. Take a look at my 2006 eclipse photo gallery for photos with exposure information: http://www.mreclipse.com/SEphoto/TSE2006/TSE2006galleryA.html
Q: How to focus prior to totality?
A: I use a Canon right-angle finder attached to my viewfinder. It has a lever to double the magnification to aid in focusing.
Q: How do you focus for infinity easily? Wide and not-so-wide angle?
A: For wide-angle lenses you activate autofocus BEFORE totality. Then turn off autofocus and tape focus ring to keep it from changing.
Q: Did you have two telescopes mounted to one German equatorial mount with a bracket? If so, how did you do that?
A: Yes, two scopes on one GEM. There are telescope accessories companies that make brackets to hold two telescopes; do a little Google searching for them. In my case I made my own custom plate out of aluminum.
Q: If the camera is properly focused in the partial phases with a foil-type solar filter, can we assume that the focus will still be the same for the total phase after the solar filter is removed?
A: The focus should not change after you remove the foil-type solar filter.
Q: Will we have access to the handouts after this webinar is over?
A: They will also be included in the thank-you email you’ll receive in about a week, along with the link to the recorded webinar.
Q: Do you prefer threaded filters or slip-on?
A: The slip-on ones are easier to get on and off (but only if they're not too tight).
Q: My childhood scope was a Tasco 70TE. Is that an achromat? A: Yes, it probably is. You can still get decent eclipse photos with it, but I would test it first by shooting photos of the crescent Moon to see how sharp the images turn out.
Q: Can you use a Dobsonian to view the eclipse?
A: Yes, but you need to use a solar filter for the partial phases and then remove filter for totality. And make sure you get the filter back on the instant totality ends (or a few seconds sooner).
Q: Is there any downside to using an SCT telescope?
A: I think they have more vignetting around the edges of the field. They also tend to have more reflections and are not as sharp as a good refractor or lens.
Q: On your checklist: don't forget a source for running chargers (AC adapter from car battery?)
A: Good point!
Q: Where do you get a small filter for one of the small video cameras?
A: Thousand Oaks Optical: http://www.thousandoaksoptical.com/
Q: I could not get the link to work until a few minutes ago. When will the recording be available, and how do I get to it?
A: A thank-you email will be sent to all registrants in about a week with a link to the recorded webinar.
Q: If you manually focus with a filter in practice runs days before totality, can you assume that focus will hold when the filter is off?
A: There are a lot of variables involved that make this question difficult to answer. What kind of lens or telescope? If you focus days before, does that mean you’ll already be at the eclipse site? Or will you have to pack up your lens and travel (which could change the focus). Why don’t you try an experiment? Focus the lens on any sunny day. Then wait a few days and see if the lens is still in focus.
Q: When do you reinstall the filter after totality?
A: About 15 seconds after the end of totality so I can shoot Baily's beads and the diamond ring just after totality ends.
Q: How big a telephoto lens?
A: 500–700 mm for a crop sensor DSLR and 700–1,000 mm for full-frame DSLR.
Q: Do you have the mirror locked up?
A: It’s a good idea, but I don't do it because I use very stable telescope mounts. Q: The exposure table you displayed for prominences (no filter) was different from the one in the handout, about 2 or 4 stops more exposure. Which table should we use?
A: Sorry! The exposure tables in the PowerPoint are wrong! Use the tables in the handout.
Q: I'm going to attempt to film the shadow bands that usually accompany eclipses. Have you done so yourself, how successful were you, and what techniques did you use?
A: I haven't done it myself, but several friends captured them with iPhones shooting video at the 2012 and 2015 eclipses.
Q: Do astro modified (IR filter removal or full-spectrum) DSLR cameras offer any benefit with eclipse photography?
A: No advantage that I can think of.
Q: When is the diamond ring phase of the eclipse?
A: The diamond ring is primarily visible in the 10 to 15 seconds before totality begins and the 10 to 15 seconds after totality ends.
Q: What's your opinion of lens doublers?
A: I used one in 1995 and it caused a lot of reflections during the diamond ring, but it was okay during totality. Because of this I don't use them.
Q: How critical is it to be at the exact center of the totality path?
A: Not critical. I'm happy if I'm within five miles of the central line.
Q: Where will you be for this eclipse, Nebraska or Hopkins, Kentucky?
A: I'll be in Casper, Wyoming, at the Astronomical League convention in the days before the eclipse.
Q: Suggestion when shooting video: use a shortwave radio to get UTC time tags in the video (WWV or CHU Canada)
A: Great suggestion!
Q: Would I be able to use a Dobsonian to photograph the eclipse?
A: Yes, but most Dobs have focal lengths that are too long, which means you would lose a lot of the corona.
Q: Do the filters stay on the scope even during totality?
A: No! Filters must be removed to see and photograph totality.
Q: Will focus change when I remove filter at totality (telephoto lens)? A: There will be no focus change as long as you don't accidently twist/change the focus when you remove the filter.
Q: Can the camera do autofocus during totality? Do we need a solar filter during totality? I will be using a Canon 7D Mark ii with 300-mm IS USM L lens.
A: I don’t trust autofocus to work correctly during totality so I focus manually before totality begins. No solar filter during totality.
Q: Can we purchase reprinted Sky & Telescope articles as mentioned here?
A: Currently S&T doesn’t offer reprints of individual articles at its online store (www.shopatsky.com), although it does offer monthly issues in digital or print (if available) format. Your local library or astronomy club may have back issues you could copy.
Q: Is it better to forgo JPEG for just RAW when shooting bursts?
A: Yes. You can shoot longer before filling the camera buffer if you shoot RAW only (no JPEGs).
Q: Is that a glass filter?
A: Yes, I use glass filters. But I hear good things about both the black polymer and the Baader filters.
Q: Any tips on determining if it will be clear where you are or if you have to find another spot?
A: The website http://www.skippysky.com.au/ is useful because it gives cloud cover predictions in the days preceding the eclipse.
Q: Are there any filters one might consider during totality to bring the corona out a little better?
A: None that I know of.
Q: Is it worth it to use AV mode on the camera if taking a time-lapse image?
A: If you're shooting wide-angle landscape then AV is okay. But for telephoto images of the Sun and totality I prefer manual exposure.
Q: How can we practice when the weather is not ideal?
A: If you shoot the eclipse through clouds, the only thing you can do is bracket and hope some of them are well exposed.
Q: Have you seen the article in American Scientist by Richard Woo [Jul-Aug 2016] saying the coronal display such as you display on your website is an illusion, even inviting people to take a picture with their cameras to prove it? Do you have any thoughts on this? I think he may be equating the limited dynamic range of even modern cameras with reality. Kind of like when we used to think visible light was all there was until a couple of centuries ago. A: I've read Woo's article but disagree. I've actually seen this structure during totality and I'm just trying to tease it out of my image sequences.
Q: Do I need the solar filter during the diamond ring phase on DSLR?
A: No filter for diamond ring and totality.
Q: If I decide to purchase a refractor but want it for deep-sky photography for years after the totality (thus a faster f-ratio), what aperture would you recommend for f/5 and for f/6, say 130 mm?
A: In terms of focal length we have: (1) aperture = 130 mm at f/5, focal length = 650 mm; (2) aperture = 130 mm at f/6, focal length = 780 mm. Both of these would be good for both the eclipse and for deep sky. However, the first is a little faster (better) for deep sky, while the second has a longer (better) focal length (780 mm) for the eclipse. So you have to choose which is more important to you.