The Starry Night, 193

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Moving Pictures

2017/06/10. Has it been that long? I aired out the telescope mount yesterday and the day before. Wasps had built a nest under the cover. It's been months (December?) since I've made an astrophoto with the Mach1. Same old complaints: I can only see ~30% of the sky from here, it glows; it's cloudy way more often than not. What's the damn point? I used to get excited about refining techniques so I could someday use them out in the dark by either carting the gear up to the Parkway or from some eventual western abode. But right now, I just don't have the enthusiasm to do the former (it's a lot of work readily spoiled by clouds or other misery), and after decades of "practice" the latter feels no closer; in fact, it feels farther and farther away. Yes, I know this is "just" depression and it will lift by and by, but right now, I need to deal with it. There's an eclipse coming, and I'm still excited about that, not least because I'll be spending about ten days on the road chasing it, and some of that time will be spent in my favorite places on Earth. All I have to do is drive ten or twelve hours a day, which would normally sound like hell, but when the aim is the northern Rockies and western plains, that's different. Add totality to the equation and August is looking pretty good.

I have all these nice EF-S lenses sitting around from my crop-sensor days when the Canon 20D and 50D were my workhorses. Since going full-frame with the 5D, the EF-S lenses have mostly been gathering dust. Since adopting the 6D (a continually astonishing camera even though it is getting a mite long in the tooth), they've become practically fossilized. Every time I see them, I feel guilty about the sunk costs they represent. But you know what they're great for? Video.

Let's learn something new!

The tiny and dirt cheap Canon EOS-M, Canon's first attempt at a mirrorless camera, makes killer video using Magic Lantern firmware. I found a used EOS-M on eBay for the price of a motel room. Cancelled the 11-24mm rental I had reserved for the eclipse to balance the summer books which left room for some other adjunct bits (EF-S to EOS-M lens adapter, mounting plates, a grip, SD cards...).

I shot Moonrise a day after the full Moon to establish exposures and to prove the kit and make sure all was ready for a spectacular photo I've been planning for months. (More about that in good time.) The Moon was way to the south, so moved much more in azimuth than I imagined it would (why imagine? I have the tools...):




I used ML's 3x crop mode and H.264 format rather than RAW (the camera just doesn't have the bandwidth to write 14-bit data at 30 or 24 fps but keep in mind that 4 or 5fps works fine). I deleted the audio, which was mostly just my obnoxious breathing.

Here's a quick clip at actual speed showing an airliner sailing across the face of the Moon. I'm guessing he's 50-120 miles away:



For post-production, file-prep, etc, I first tried a command-line tool called FFMPEG. Wonderful bit of freeware with lots of capabilities. For example, it provides access to RAW video, but I'm not sure how much it can do with it. FFMPEG merely whetted my appetite for real editing tools. So I downloaded a trial copy of Premiere Elements 15. I loved it at first sight. Licensed it within the hour. I sped up Moonrise some. Now the video needs sound: crickets, nightjars, distant traffic, and so on. Got ambitious. I said to myself, you know, if you made a film about chasing the eclipse, it would keep you busy collecting A- and B-roll footage and ambient sounds from the moment you leave until well after you get back... It's well worth extending the 2m40s of excitement around totality to weeks.

So I went back to eBay and hunted a Tascam audio recorder for cheap. I considered the DR-05, DR-07, DR-07Mk2. (That's 95% for ambient sound; it might need an add-on mic for voice-over, but in any case that will be taken care of back home.) I could have had any of those recorders for about the same price, but I went with a pawned DR-05, partly because it's a currently supported model and has a wide following online for advice and accessories. I ordered a wind-muff for the recorder's built-in mics. I found a Fujian 35mm F1.7 C-mount lens in China including a C-mount adapter and a hood for not much more than snack money. That glass has many fans on YouTube. People love it or hate it. It's soft on the edges of the APS-C format which focuses attention toward the center which means it behaves almost like a perpetual selective focus, and at F1.7 it does offer a reasonably selective focus. I think the effect is neat; the lens is cheap and tiny. The 10-22 Canon EF-S will likely be my go-to lens for video on the EOS-M, but it's basically irreplaceable by me at the moment. A less pricey lens I wouldn't mind putting at risk is worth having.

I imagined what the prospective eclipse film should look like. Lots of walking around shots, surely. I can't afford a motorized gimble to make them smooth, but there are tons of SteadyCam-like brackets out there. Practice (keeping busy is good!) but no batteries required. I researched the well-reviewed models, studied YouTube samples, made sure the SteadyCam wannabes could handle my 6D when it inevitably gets used for video, too, identified the camera bracket I thought best for the job, then went to eBay to find it cheap. Did, too! Slightly beat up, I gather, but perfectly functional. I'll need to manufacture some extra counterweights for it and supply the top camera bracket (no problem: there's a lathe and scrap metal downstairs, and I'd probably work with the stock stabilizer to make use of Arca clamps and plates anyway; in the meantime, any old 1/4x20 screw will do).

So now I'm putting Adobe Premiere Elements through its paces. I time-lapsed an incoming storm yesterday and learned some lessons (10s is too long between shots for weather vids, so try 5s; you can speed up video more easily than you can slow it down because frame blending only goes so far, else there is a lot to learn about that, which is entirely possible and even likely; etc). There are indeed two ways to do timelapse: shoot individual frames and assemble in post, or set a slow frame rate. The latter is slightly tricky because of the way Magic Lantern sets exposure times, but that can be gotten around within reason without neutral density filters by using the right ML options. All in all, frame by frame offers vastly more flexibility. And I'm learning how to edit video in Photoshop, too. Yes you can! And very nicely, too.

Yes. Yes, I am a pig in mud. Kinda the point. It's cheaper than meds or therapy and in the end I get new skills to show off. Speaking of showing off... must find the best place to host videos. Vimeo, perhaps? (Yes. I asked a pro; that's the host he uses to share preliminary footage.)


6/16. The guy selling the stabilizer had the wrong email account associated with his eBay account so today, 5 days on, he wrote asking if I still wanted it and if he could he count on my paying for it soon. We had a pleasant back and forth while sorting out what had gone wrong. Half an hour or so later, all is well, and now it's on the way. 'Salright. I want to practice with it before August, but that's still a ways off.

I spent way too much time last night trying out different mounting schemes --Arca plates, screw mounts, clamps, ball-and-socket mounts, 1/4x20 screws, bushings for 3/8-inch screws... and finally I put a decently convenient kit together that, at least for now, requires few if any additional parts.

(6/17: the handgrip for the EOS-M arrived, and I saw that its built in Arca dovetail wouldn't allow it be attached with the EF to M adapter in place. So I sawed off part of the dovetail. It still has a mounting hole for a tripod screw or an aftermarket plate. And then I discovered that the mounting foot comes off the adapter. Mine may still be the best avaialble solution, but dang, there were other options to consider. I shall try not to dwell on them. Any of them can be adopted for the price of lunch, but dang. A three-suction-cup camera mount arrived, too. Solid, but a bit large. I put a better ballhead on it. Will order some single suction-cup mounts for almost nuthin' just to have options.)

I realized that I needed some video of afternoon thundershowers moving in for the "why go west" or "at the sky's mercy" bit (and just for funsies), so I found a 9-inch acrylic dome on Amazon to put over the timelapse camera. Let it rain, let it rain, let it rain. Apparently, all vendors get these from China and it's going to take a while whether you order one from Amazon or on eBay. (I also ordered two more batteries for the EOS-M and another charger since that will be my go-to camera for some aspects of my summer travels. That's five batteries, btw, which does not seem excessive since it can burn through them with that always-on LCD. Also silver Sharpies to number batteries to help keep straight which are full and which are not.)

The Tascam DR-05 is here a couple of days early. It's the newer Mk2 model. Great! I drove around with it hanging from an improvised lanyard in the Honda and marched around the yard some with it around my neck. I had the wind muffler in place. Very impressive sound! I've asked Patrick for tips (if people ask me for digital imaging tips, I can offer them so I figured PC would have his short list of good advice, too [he did!]). We're getting there.


6/18. I shot another Moonrise. I went to the access lot for the show at about 2:40AM, and grabbed a few stills of a blood-red Moon low on the horizon, but it immediately disappeared behind strata for another 30 minutes. I started to come home early, but thought, hell, you're here, set up, ready to film, so just wait. I think it worked out well. Before midnight, off the porch, I'd recorded one of the Chuck Will's Widows that punctuate our woods. Then I recorded frogs in the wetland. So those tracks are appropriate for Moonrise from just a few hundred feet north of the house. Here:



There's a scad of tech-talk to go with that. By and by, I'll figure out what needs to be recorded and reported. In the meantime, g'wan: Make it full screen and zen out.

That's shot with the EOS-M in H.264 format (i.e., not raw) in Magic Lantern's 3x crop mode. 1/30 sec at ISO 800 at 1920x1080, 30 fps, through the AT65EDQ on a fixed tripod. Audio from the Tascam DR-05v2 using its stock omnidirectional mics in mono mode at 48k under a wind muff. I suspended the Tascam from a light-weight cord to avoid handling noises. Post for the audio was Audacity 2.1.0 (noise reduction, high-pass, looping for length) and for the video Adobe Premiere Elements 15. I rendered the clip at the original resolution in realtime. I tried speeding it up, but it lacked majesty.

Here's a shorter take over Dreamworks-ish clouds:



That one's been sharpened in Photoshop (load, convert to smart object, apply mods, render; also, adjustment layers are your friends though I didn't use any this time).

I think the framing of the Moon is fine for Moonrise and such, but it is a little too tight for the eclipse. There's every chance I'd misframe in the heat of the moment, finder-scope be damned. So I've removed the AT65EDQ from the collimating rings and mounted an ancient 300mm Nikkor in its place. I had to rob an EOS adapter from another lens for the 300mm, so restock those sooner or later. Framing is much more relaxed but the image scale still seems fine. It needs testing for stability, focus, and sharpness. The 300mm F4.5 Nikkor has the same clear aperture as the AT65EDQ (really, do the division!) in a much more compact, cheaper package (you can buy these all day, including even better EDIF versions, for $75 and up).

The video bug has bit, so I noticed on one of the tech-bargain websites a coupon for $20 off a GoPro knockoff at from Amazon. With Prime delivery, the total came to just $25, so it was just a question of verifying a few options before I said, sure, send me one of those. It has a 170-degree (corner to corner) field of view (135-degrees side to side); shoots 1920x1080 @ 30fps, includes a waterproof housing, and can do time-lapses (great for storms, I hope, and to be positioned where I wouldn't risk other cameras). It's actually surprisingly well-reviewed (in some places anyway) and examples on YouTube look very good. So there's your wide-angle eclipse camera right there, also a wx time-lapse camera (maybe).

Here's the current line-up for the eclipse.


Camera Optics Still or Video (mount)
6D TMB92SS Still (on G11)
EOS-M 300mm F4.5 Nikkor Video (on G11)
5D 14mm Rokinon Still (on tripod)
50D 10-22mm EF-S Undecided (on tripod)
SJ4000 fixed Video (suction mount?)
iPhone fixed Video (suction mount?)

You're going to need a couple of bigger MicroSD cards for the SJ4000 and the Tascam recorder. Make sure you can charge the SJ4000's batteries on the fly (the rest are covered). I've ordered fresh batteries and a car charger for the 5D and 50D since we're using them for a wedding next week (I have batteries and chargers for the 6D --find them and test them all!).


6/21/2017. Happy equinox. Happy two months to totality. I tried the 300mm Nikkor on the EOS-M after kludging up some shims (strips from old padded mailing envelopes taped around the hood) for the solar filter I put together for the AT65EDQ. Inifnity focus is NOT at the infinity stop. On inspection, I see that I have scribed the focus scale to indicate where it is. The barrel will need to be clamped / taped / somehow secured for astroworks. I would think tape would do the trick. It also might be worth stopping down to F8 or so. Try some moonshots to judge sharpness and focal tolerances. And do better about attaching the solar filter.


sun 300mm 3x crop

300mm Nikkor and EOS-M
video frame grab from 3x crop mode. Baader filter material.


Compare the size of the Sun in that frame to the size of the Moon in the videos up above. And yes, of course it is easy to crop / enlarge the image in Premiere Elements if you do want a big, imposing disk. We're winning.


6/27/2017. You know the way the Moon shines through pine needles, lighting them up as it approaches alignment with them? Well, you might think it would do that when within 2-3 degrees, but it has to be lined up to more like 0.5 - 0.25 degrees. This matters if you're trying to shoot video of the Moon rising or setting behind pines. Now you know. You're welcome.

I moved the pipe-clamp micrometer screw tangent widget from the 200mm F2.0 Nikkor to the 300mm. (Yes, I'll include a picture by and by!) I cut a piece of aluminum as a fixed point for the micrometer screw to push against and used an old leather belt for shimming the too-large clamp. A couple of rubber bands applies pressure to keep the tangent assembly pushing against the fixed plate. Looks funky, but it works great! The Nikkor has some serious achromatic deficiencies when even slightly defocussed. With the Moon, these can be controlled by muting red and magenta. You wouldn't want to do that with the eclipsed Sun. I've put a magnifier in the kit to make it possible to focus like mad. I think I have a minus-violet filter around here somewhere that will fit this lens.

Oh: and when you decide to speed up a clip, use the "tools / time remapping" option in Premiere and enable "frame blending" rather than "tools / time stretch" which appears to just skip frames. It didn't occur to me until I was doing something else entirely this morning that frame blending must involve something related to a running mean for each pixel and that should mean substantially reduced noise. It does!

I've got the Roxant stabilizer working with a handful of pennies for an adjustable counterweight and a long sliding Arca clamp up top for balancing duties. We're ready to practice and take names with that thing. After Iowa, before Wyoming.

And while thinking about how to do family portraits at F1.8 in the Iowa sun, I remembered my stashes of ND filters and step-up / step-down rings. Alas, no rings in hand adapted 72 or 77mm filters to the 58mm front of the 85mm F1.8, BUT, one apt ND filter is a press fit into the hood of that lens. It will do for the rare occasion. Hello, bokeh!




My deep-sky photos are made with a variety of sensors and optics. Deepest images usually come from a SBIG ST2000XM CCD behind a 10-inch Astro-Tech Ritchey-Chretien carried on an Astro-Physics Mach1GTO. The CCD is equipped with a CFW-10 loaded with Baader wide- and narrow-band filters. Camera control and guiding are handled by Maxim DL 5.12. A Canon 6D and a modded 50D find themselves mounted behind an Orion 10" F4 Newtonian or a 92mm Thomas Back refractor or a tiny but mighty AT65EDQ refractor, sometimes with Backyard EOS in control and PHD Guide keeping things on target. Really widefield photos are often made using the 6D and various camera lenses and an iOptron Skytracker mount. PixInsight does most of the heavy lifting in post-processing — alignment, stacking, gradient removal, noise-reduction, transfer function modification, color calibration, and deconvolution. Photoshop along with Focus Magic and a handful of other plugins get their licks in, too, especially when polishing for the web.


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                   © 2017, David Cortner