Sunday, November 27, 2011

"More people drop out of distance races due to stomach issues than do from injury"

These words would turn out to be prophetic, but the trip actually went very well otherwise. We had about three and a half days out on the mountain, lots of climbing, a good stopover on the way home, and much much more. No major injuries (cuts, scrapes, bruises: the sort of thing you expect from a climbing adventure). Most of the gear worked out wonderfully. There is a lot of story to be told, but first I'll introduce our crew:

Mike: Brother. Filmmaker. 32lbs of gear, including a portable articulated camera crane system he made in the weeks before. Probably the most ambitious project of the trip.

Marcus: Friend, filmmaker, professional adventurer, maker of goofy faces. 31lbs of gear, not including some of his camera gear and dolly rail. I suspect closer to 40lbs.

Me: ex wildlife photographer. 30.6lbs of gear, including all camera gear and astrophotography equipment. Wearing the wrong kind of backpack, last minute change-up.

Tuesday, November 22, 2011

It starts now...

No chance to post the gear pics, but at this moment we are embarking on the long drive.  Full tank of gas, half a subway sandwich, it's dark and we are wearing sunglasses. Hit it.

Monday, November 21, 2011 here we are...

This might be my last post before we dash off for this trip. Hoping to have one more showing off everyone's gear and inventions, but we shall see...

This morning was one of those silent drives in to work despite having the radio on. Something about having the air conditioning come at you full blast on an already cool morning, a bit less sleep than normal, and then climbing out of your car to put on a backpack that has both work stuff and dead weight in it while trying to avoid aggravating the cut up hand so it has time to heal that makes you think a bit. I think some get the impression that these things start at the trail-head.

I was up late last night chatting, having the best distraction I could think of, but my head is in the game this morning. Prior to that we made our last trip to Aiguille. Both Mike and I did a little hand damage which I hope will be completely healed before we hit the natural rocks.

I realize I did not get everything accomplished that I had set out to. In fact I have not even finished putting an enclosure and battery pack around my astro rig just yet, which I absolutely need to do. It would be pretty lousy to get out there and have some wire pull loose because it snagged on something during setup.

I never got to dive in to the cable dolly project. I'm hoping I still have cause and drive for this when I get back so that it can be ready long before the next trip.

Also... I'm recognizing that I'm carrying a heavy load on this trip both physically and metaphorically. I still need to do a final weight, but I think it's right around the goal 25lbs. Maybe a little over. This actually feels pretty heavy to me for whatever reason. I'm glad I set the goal there and not higher. On the metaphorical front: I have always been the caretaker of others. I may be the team medic on hand, which is ironic considering my propensity to injury. Additionally I have decided that I will be the one who doubles back alone to pick up the crash pad while the rest get settled. I'm a distance runner and the pad is only 9lbs, so I am far and away best fit for this job. Should be clocking some altitude training on this.

Every once in a while the body decides to remind me of the life I live: last week I started getting an unfortunately familiar itch on my chin. A couple days later a small piece of gravel worked its way out. I cannot specifically say which injury embedded that piece in my face.

Sharks and squids swimming around in my head...

Sunday, November 20, 2011

Get Sirius...

Tonight's test was all about not having to calibrate. Due to location I couldn't actually see Polaris, I just pointed north and guessed. Tracking? Leave that to the math. First shot was just to pick out the brightest thing in the sky and see how close I was. Note that these are untouched single frames, no processing at all:

(30 second exposure @ 300mm)

(Another 30 second exposure)

This image is a reminder to me about why it's important to go where there are dark skies. This is 180 seconds (to take some longer exposures and see what I could get). Perfect tracking, can even start to see some of the milky way in there. However the local light pollution is what's really limiting me from having some fun. I tried a couple of 5 and 10 minute shots just to see if I was staying accurate, but they were completely blown out with the orange glow. They still were useful though, I could tell the only error was in alignment (which was surprisingly low considering the careless approach)

Friday, November 18, 2011


From the moment I received the celestron motor drive I was slightly disappointed. I immediately had to file out the case so that the switches could swing full from side to side, and as soon as it powered up and I realized it was a simple DC motor with a dimmer...well, I knew it would mean more field calibration. And calibration there is no way I could make perfect without spending a lot of time watching the camera drift, wasting precious battery and dark time.

I'm a motion control guy. This doesn't seem like a difficult thing. The earth turns at a very predictable rate. A sidereal year is 365 days, 6 hours, 9 minutes, and 9.54 seconds (if we're being overly accurate.) That means there are 31,558,149.54 seconds a year, therefore it takes 86,164.09 seconds for the sky to come full circle once. It would be easy and cheap to use something that is positionally accurate, gear it a bit, and make a controller... -a real controller- that tracks properly and without need of calibration for my purposes.

So I broke out a classic: the arduino clone known as the boarduino, of which I don't bother with a lot of the components but make use of their lovely printed boards (Thanks Adafruit!). In total it cost me about $7 in components to build the controller. Ebay was also full of miniature geared stepper motors (85:1 gearing, 5v native, etc, etc). If you have the patience to get one from Hong Kong it will cost just a couple of dollars. If not (I'm running out of time) it will cost you $6-12.

After some creative programming I calculated the potential accuracy of my setup. The oscillator isn't perfect, and neither is my code, but in total the maximum error seems to be around the equivalent of 5.6 seconds of missing sky per hour. This would just barely show up at my longest lens if I were taking hour long exposures. I don't honestly see myself taking single frames anywhere near that kind of time. Perhaps a couple minutes per exposure at best. Chances of me hand calibrating a DC motor to this level of accuracy? Nill. If I thought it needed to be more accurate I could adjust for the oscillator and coding errors- but who cares?

Now to make a mount for it...

Sunday, November 13, 2011

Update; Celestron tracking mount

Bronze bearings, chromoly axle shaft, and is that a stepper motor? Now we're getting somewhere...

Thursday, November 10, 2011


Very busy, but here's the answer to a previous question: Henry Shires Tarptent Sublite. 19.5oz, plus another 5oz in poles (I don't do trekking poles). Packs down to 14x4" roll and apparently is pretty good even in heavy weather.

I also had a chance to throw most of the other stuff in the bag and get an idea of the weight involved. I'm not sure if I weighed things incorrectly at some point, forgot stuff, or what but everything I thought was on my list plus an extra lens came out to 16.2lbs. Which would be very, very nice.

Monday, November 7, 2011

Improving the Celestron CG2 tracking mount

When you take something apart and put it back together a few times you start to question just why the designer did some of the things they did. There are probably good reasons (some of which would be out of the designer’s control, like price, production formats, assembly costs, etc). However when you’re not so limited by these things…some of the results really stand out. No hate on the designer, they did make a tracking mount that wasn't all bad for wonderfully cheap.

So allow me to present the problem:

If you have a looksie at this diagram you’ll see that because the main barrel of the tracking mount is cast the tolerances on certain sections are not very good. Even if they were it would still be difficult to get exactly what is needed using soft aluminum.

Rotation in direction A there is the enemy of tracking (well there are other things too, of course, but this is the one I’m poking at). The way the original mount is designed this play is controlled either by tension in direction B, or the tolerances between the axle shaft and the walls of the cast tube it resides in. Since there are no bearings B cannot be very good, and because this is cast A cannot be very good.

What really strikes me about this is that they cast this long tube, which if they had made use of could have helped this issue a great deal. My solution will add a little more weight back in to the fixture but I think it’s worth the sacrifice:

Longer shaft means play has less effect, and tighter tolerances are made by using pre-made bronze sleeve bearings on either end. As much as I’d love to put in precision tapered needle bearings? This is not the place for that. In total it will cost me $7 to change these parts out, and I will need to do a small amount of machine work. Parts are on order…

Double rainbow

All the way across the sky. For rizzle. It was an intense morning.

Sunday, November 6, 2011

More weight savings- the old fashioned way...

Replacing gear with lighter gear is both expensive and doesn't work for everything. Especially when there is no equivalent that was ever intended to be light and packable. This is where it's nice to have a CNC machine and a lathe on hand:

I attacked my poor star tracker again; this time with the above tools. I cut sections out, lathed down the worm gear center, shaved whole sections off, and even hollowed out the heavy elevation studs. Total I managed to cut another 155 grams out of the assembly, or 0.34lbs. There will be more coming out when I change out the tracking assembly for one of my own design, but for now this is no longer the heaviest thing in my pack. That might be more of a mental win than anything. Actually it now weighs less than my sleeping bag. Oh, and it looks much cooler too:

(tracking motor not attached in this particular photo, but accounted for in weight)

Friday, November 4, 2011

Off Topic: Sleep Data

Random, off topic post for a Friday; I got some results back from a sleep study and I thought I would share. Or at least share the data; I'm not sure what the data means yet.

  • A normal sleep cycle (REM -> slow wave -> REM) averages about 90 minutes. My sleep cycles are more than double that.
  • The majority of my REM time happens after the alarm. While it's not unusual to have some REM time in those early moments...long term waking dreams is kind of a strange thing.
  • REM did not transition to waking state before the gear was turned off. Which sort of makes me wonder how long after "wake-up" I'm still in a waking dream state.
  • Actual sleep time is way below average. Much of this has to do with very long time to fall asleep.
  • Proportions are pretty far off too: very little deep sleep proportional to the statistical mean.

Thursday, November 3, 2011

And there you go....

Total we clipped a bit less than half a pound out of the rail. Not amazing, but definitely noticeable. looks really cool.

Wednesday, November 2, 2011

Do unto others..

Last night was about working on one of the other people's camera hardware. He purchased an aluminum linear rail system that he wants to modify to be a portable rig. Unfortunately it was made to be extremely heavy; presumably to give it some dampening power. Wonderful on a set, but a huge pain for what we have in mind.

We've started shaving some weight out of it using the CNC:

The rail is 5/16" thick for the center support. Really, really overkill, but he wants to be careful to reduce the stiffness as little as possible. My solution is to cut grid out of the areas between bolt holes. How far he wants to take it from there I'm not sure, but it's a good start:

We finished two of the sections last night, plan is to do the other two tonight. Always pleased to have the CNC fire up and do everything it's supposed to. That's one of those projects that keeps coming back to me and letting us do things we would not have considered before.

Tuesday, November 1, 2011

first shot at saving some weight...

It seems strange to me that my tools section is more than my survival section. I'm starting there.

Tools, 1856 grams:
  • Gerber Multitool, 170 grams
  • Modified Gerber FAST pocket knife, 87 grams
  • Fenix E21 flashlight, 139 grams
  • 100 Feet of ParaCord, 180 grams
  • Mission Workshop Rambler backpack, 1280 grams
I've had that same multitool for about 15 years; it's not heavy, but it's not light either. Plus most of what I need out of it is the pliers, and a little flexability in case something doesn't go well in the field. It actually has another knife that I don't use because, well, it isn't very good and the FAST is very good.

So Item 1: Leatherman Style PS-8. Clocking in at just 45 grams.

Second item, the FAST knife. I'm keeping this, but I might shave a little more weight out of it. Will come back to that.

Third item: flashlight. Fenix for Fenix, this is the LD01 at 28 grams including battery:

Fourth Item, paracord: I can't see myself needing more than 50 feet. Cut that weight in half.

And last, and most painfully, I love my Mission Workshop backpack. It's a fantastic bag. I can't say enough about it, except that for the volume it weighs too much. That makes it the perfect bag for everything except this. Sadly I think it will have to stay home.
GoLite Peak, 625 grams without the hip straps (which drive me crazy on every bag I've ever had with them).

Total savings? 981 grams, or 2.1lbs. I wish I could have that kind percent savings across the board, but something tells me this is the easy one...