Giving a Talk on Lunar Imaging - Any Tips Please?

[Knight of Clear Skies]

I've been asked to give a basic talk on lunar imaging at the Caradon Observatory open days later this month. i'm not brilliantly qualified to do this, but I have at least managed to pointing cameras and telescopes at the Moon to get some reasonable images. The talk will be pitched towards the general public.

I was planning to wing it a bit (if that isn't a contradiction in terms), but I've sketched out an outline of what I have in mind:

• The Moon - the easiest thing to image in the sky. (Relatively large, bright, doesn't require specialised equipment to show details unlike the Sun.)
• My entry to imaging - coming from a low base, some pointers from an astronomer & SGL but plenty of trial and error.
• Apparent size of the Moon? Props, orange, walnut and hazelnut at arms length. Surprisingly small, can hold out arm and obscure it by holding out your little finger.
• DSLR imaging with telephoto lens simplest approach. Moon (& planets) quite bright as they are directly illuminated by the Sun. Similar exposure settings (explain exposure concept here? leaving the shutter open long enough to collect enough light) to looking at objects on Earth. Moon is about as reflective as worn asphalt, so similar brightness to a car-park.
• Show example DSLR images and camera/lens I used to take them. Handheld shots and autofocus fine.
• Point out a couple lunar features, landscape dominated by impact craters and volcanic maria. No weather or plate tectonics on Moon, so craters persist for much longer than here on Earth. Craters stand out more when the Sun is at an angle, casting shadows.
• What if we want to look closer? Use a telescope, but this introduces challenges. The more magnification required, the more precise the optics need to be, the finer the focus, the more stable the mount needs to be and the greater the effect of atmospheric turbulence.
• Demonstrate atmospheric turbulence by lighting a candle and holding an image of the Moon above and behind it? Same principle, not such a temperature difference but we are looking up through several miles of atmosphere. Try not to burn down Moon when doing this.
• "Lucky imaging" - sometimes the atmosphere presents an undistorted image. Best solution is to take a video to catch the best frames.
• Webcams. Show X-box camera and DMK camera.
• Show raw video of lunar capture, shimmering image.
• Post processing (Registax) to extract clean image from video. Choose good frame, software finds good matches and combines them. Sharpen with wavelets.
• Show lunar mosaic taken with DMK.
• Same technique for planets but they appear smaller. Put lunar image and Saturn side-by-side (taken with same scope and camera so in scale). Time to move to a bigger telescope....

 

Here's a couple DSLR images i can show them, taken with my 250mm lens:

 

 

 

And here's a basic mosaic I put together using a small refractor on a fixed tripod:

 

 

Does this sound reasonable to people please? I haven't done this before, so any thoughts or tips would be appreciated.

[oldpink]

on a couple of occasions I've had to speak in public
best advice be yourself and talk from experience but you seem to have that covered

good luck

[houston]

Sounds spot on for the general public. You may frighten them off if it starts getting complicated. Maybe explain why we see the different phases of the moon? Size difference of our moon and other moons? Good luck

[JamesF]

Do mention that it's considered terribly bad form to do a lunar mosaic and not "miss a bit".  Getting the entire target is the mark of a rank amateur.

James

[Umbraldot]

Public speaking is not so much about what you say but the way you say it. Know your audience. You can be more technical with the informed audience but basically people like to be entertained and not bored. Lots of nice pics like the ones you've demonstrated and a good lively performance to keep people awake is essential, 30 - 40 mins max plus Q & A's.

[Luke]

Sounds good to me. The only thing I can think of is whether it might be worth mentioning images taken with a phone. I've seen some pretty good moon shots taken with a phone held to the eyepiece.

[Zakalwe]

Do mention that it's considered terribly bad form to do a lunar mosaic and not "miss a bit".  Getting the entire target is the mark of a rank amateur.

James

I must be an expert then.... :mad:

@Knight of Clear Skies: Unless you are very knowledgeable on the subject and are very comfortable with public speaking I wouldn't try to "wing it". It will come across as winging it and its much easier to become "lost" in the speech and end up wandering off track, or worse, grinding to a halt and losing you thread and confidence. It also make it much, much harder to time your presentation which might lead to you rushing through some bits and finishing early, or timing out and not finishing your points.

Personally, when giving speeches, I mull it over in my head for a good few days before putting pen to paper. When I have a rough idea going on I then write out the key bullet points, as you have done. I then work out a storyline and flow-chart (nothing complicated...just scribbles really).  I then identify key points in the presentation and commit key words to memory. These key words become the points that i use to bring me back on track if I get lost or wander off topic. They also provide me with time-checks.

Once I've got that down, then and only then, do I start to work on Powerpoint or slides. I find that if you start with PowerPoint the program stops your thoughts. I personally am not very good with PP and I find that my brain becomes occupied with driving the program, rather than using the program to illustrate my message.

My key words are always on the slides. Don't make the slides too "busy". Forget about gee-whizzy slide transformations, animations and slide-builds. Use the slide as a "skeleton" on which your talk will hang. The slide is there to provide the audience with the salient points of what you are about to talk about. Too much detail or distractions and the audience spends too long trying to digest the contents of the slide and then they might miss your first few sentences. Remember that we are visual creatures......information via the eyes will take precedence over information via the ears.

Once you've got it into shape, practice it. if it helps, write your key words on some numbered cards, or on a piece of paper. That way, if you get distracted or lost you can easily come back on plan. Write the time point that you expect to be at beside the key word so you can keep your pace.

[C7tsj]

@Knight of Clear Skies - I think your bullet points are fine. Put yourself in their shoes, they probably want to know what the moon is, why it looks like it does, size, phases and then how we can image it with simple kit.

Good luck, you seem to have also bases covered and nice shots, especially the one with the BA plane.

Mark

[Alkaid]

I like your bullet points. For presentations, always remember the 7 'P's. Proper preparation and planning prevents p*ss poor performance. For the general public, keep it light hearted and try to grab their attention. Sounds good!

[Knight of Clear Skies]

Thanks for the ideas and tips everyone. I'm going to keep things short and fairly simple, but hopefully bring in a few bits of trivia the audience won't have come across.

Sounds spot on for the general public. You may frighten them off if it starts getting complicated. Maybe explain why we see the different phases of the moon? Size difference of our moon and other moons? Good luck

Yes, I should mention that, and the length of the Lunar day. I can also explain tidal locking as the reason we always see the same face of the Moon from Earth, and why literally speaking there is no "dark side" (with apologies to Pink Floyd).

Sounds good to me. The only thing I can think of is whether it might be worth mentioning images taken with a phone. I've seen some pretty good moon shots taken with a phone held to the eyepiece.

Good idea, I should definitely mention eyepiece projection. Some phone pics I've seen are better than anything I've taken myself.

Do mention that it's considered terribly bad form to do a lunar mosaic and not "miss a bit".  Getting the entire target is the mark of a rank amateur.

James

I must be improving then - I've had another go at making a lunar mosaic since that one and managed to miss about two thirds. I started shooting a multi-panel monster with a 12" newt, but I'd chosen my exposure settings poorly. They were fine for the darker region, but the brighter ones were badly over-exposed. I was about to start again, then the clouds rolled in. Not a complete waste of time though, I have some crater close-ups I can show when I get around to processing them.

Some others things I could talk about:

- Cratering is an ongoing process. Before and after pictures of a new crater discovered by the LRO, and mention that amateur astronomers (very) occasionally see flashes from impacts.

- To give a sense of scale, Tycho crater is about large enough to fit Cornwall into it. Quite a bang. A relatively young crater (~100 million years old). Dating from rocks collected during Apollo missions, and crater rays overlay older terrain and craters.

- No stars in pictures of the Moon. They are present but too faint to show up (exposure settings), which is the same reason they aren't visible in pictures taken from the Moon's surface.

[barkis]

Make yourself interesting. Be like a salesman going out to sell his Company's products to a new customer.

The buyer will want to know what you are like long before he makes his mind up to buy what you are selling.

Tell a joke (A clean one by the way), and try to get a laugh out of them, it's great for relaxing you and them.

Believe it or not, they will have as much trepidation as you, if not more.

Keep it simple, the moon is a simple subject to talk about, and the main point of interest to most, is the fact that man has walked on it's surface.

Happened a long time ago for sure, but still fascinates folks, especially young uns, who perhaps would like to be astronauts.

Once you take off, and have their attention, and your nerves have calmed, you will sail on easily, perhaps forgetting the time even, and running over.

and causing them all to miss the bus home . 

You'll be fine, believe me.

Ron.

[pete_l]

Your list looks like an awful lot of material to cover - how long are you intending to speak for?

I can speak from experience and say that I always prepare too much for the time alloted. Broadly, I find that a page of a dozen or so bullet points can easily take 1 hour to present and that once you're "on your feet" time seems to shoot by, so keep a clock visible and stick to the time you assign to each of your points.

All the advice given above is completely correct. Be yourself: you're not under cross-examination and neither are you giving a lecture at a technical conference. If you are unused to public speaking make sure your voice is LOUD ENOUGH to be heard at the back of the room - this takes practice. And speak slowly: people usually speed up when they are nervous or excited, but audiences find that more difficult to follow, so make a conscious effort to ... speak ... slower ... than ... normal (but don't put them to sleep)

So far as the content goes, please don't over-sell the ease of lunar imaging "it's very simple, anyone could do it - all you need is .... " As we all know from experience, it's not easy at all and takes lots of practice and many, many shots to get the right combination of camera speed, focus, exposure, lack of "shake" etc. And introducing a telescope multiplies the number of variables and therefore the difficulty of getting them all spot-on many-fold. If the presentation sets the expectation that all you have to do is point your camera at the Moon and go "click", they'll all try it and get lousy results - and won't explore the possibilities any further.

It looks like you are planning some demos and example photos/video. Be prepared for none of them to work   and make sure that "those at the back" can see what's going on. Also be absolutely certain that all your equipment is set up and works exactly right on the day, in the room (question: will the room be dark enough for people to see stuff on a computer screen?). This is NOT something that you should ever trust to anyone else to set up and cannot be "winged". You will need to get to the location an hour or two early and set up all your stuff yourself. Then rehearse it all and reset it again ready for the presentation.

Also, bear in mind that nobody will be taking notes, so if you are going to talk about software and techniques, everything you say will be forgotten 5 minutes after they walk out after the presentation. If you want people to follow through, maybe have a fact-sheet as a giveaway with pointers, web links, key=words on it - but don't make it more than an A4 sheet. And don't put your name, phone or email on it unless you want to spend time talking people through the process in real time. Once you give out contact information, your audience "pwns" you.

Finally, (phew!) the general principle of presenting is "show, don't tell". So if you want to get some information across, don't just tell people the facts - show them what it means. If you are planning to say that the Moon is the size of a thump at arms length, get a thumb and show it to be so. How you arrange to do these things is your choice, just keep it simple so people don't get lost in the technology.

And Relax.

[Knight of Clear Skies]

Some handy tips on the practicalities there thanks. I wouldn't take my 'winging it' comment too seriously. I'll be fairly well prepared but I won't go as far as writing a script. I'm familiar with the lecture room (it doubles as a pool room!), and I'll be on site a couple days beforehand to play with the setup. I'll have my laptop, but to ensure people down the other end of the table can see OK I'll plonk a few printed images down there.

Time could be an issue, many of the bullets will just be a few sentences but it all adds up. I'm aiming for a very high level view, there will be a Q&A session afterwards or people can talk to me individually if they want to get into more detail. For example, I won't show them Registax but I will show them the source video and its output. I'm going to have to think about which points to cut.

Mulling it over, I need to go into what the Moon is and the reasons why you might want to image it as an introduction rather than take that as a given. Our nearest neighbour is an alien hostile world, with no atmosphere, extremes of temperature and low gravity (you could jump about 10 feet straight up, and in theory Tiger Woods could hit a golf ball a mile). It's not as interesting as the Earth (we have TV, whales and chocolate), but it illustrates how different a planetary body can be and how special the Earth is. It affects us here on Earth (tides and keeps the Earth steady on its axis). The phases present a changing view, I like to image it when partly full as the shadows make the craters stand out more. We've barely explored it - a dozen astronauts have landed there but its a little like sending one pair to China and the next to India.

Hopefully that will provide a bit of a hook.

In terms of follow up, I'll probably write things up in more detail and add an article to the observatory website. Here's my take on the M82 supernova for example.

[Knight of Clear Skies]

Thanks for the thoughts and tips everyone, really helped me to get myself organised. In the end I didn't give one long presentation as we managed to get a fair bit of solar and planetary observing in over the two days, and we had plenty of other activities going on. I spent a lot of my time showing people the Sun through the Solarmax and Jupiter through the 12" dob. However, I did use a lot of materiel and images that I'd prepared in short snippets, talking to people in twos and threes. It was all very relaxed and good fun.