Monday, July 30, 2012

Observatory--Part 5: FAIL!

I ran into the first major problems today.  I thought the rest of the build process would be straightforward.  I was wrong.

Today's effort was focused on building the top frame of the observatory on top of the walls.  I pulled out the two 12 foot long, treated lumber 2x4s, cut them to length and cut the corner miters. I placed them on the walls and the corner posts and two problems became apparent:

1.  The boards were slightly warped--the twist was relatively slight (I checked the boards carefully when I bought them and did not notice it).  However, anchoring one end of the board really exaggerated the warp at the other end.  I thought screwing it down aggressively might straighten the warp, but it didn't.  I tried building in 2x4 braces at 3 foot intervals to see if attaching at a number of points might straighten the warp, but that did not work.  I even tried using two 6 foot long 2x4s with a center brace, but the solution was not practical because of issue 2, below.

2.  The second problem arose from the fact this is a scale-up from smaller sheds.  The center wall brace on this shed is 2 inches wide, which "kicks out" the 4x4 corner supports.  The top 2x4 frame piece can rest on the edge of these and also on the top of the wall.  However, the wall is "corrugated," and it is very difficult indeed to cover the gap caused by the "outward projecting" corrugations and rest enough of the 2x4 on the corner braces.  I thought about cutting notches in the corner supports to have them rest more snugly against the wall, but decided that it would be too difficult and might have other consequences when the 4x4 beams and the roof are added to the weight to be supported.

All in all, it was a frustrating afternoon.  I achieved precisely nothing and had nothing to show for all the work done today.  I think the only practical step is to make the top frame from 2x6s.  These will be wide enough to rest on the walls and cover all leak points, and they will also have appropriate overlap with the corner support pillars.  Today is the end of build activity for most of the week.  I'll buy more timber on Friday (and be very careful to check for warps) and try again.  I'm definitely sadder and wiser this evening.

Sunday, July 29, 2012

Observatory Part 4

Today was floor day--my son Scott and son-in-law Nathan helped me immensely.  I'd pre-cut the floor panels, knowing that I would have to trim them to fit.  I would have preferred to have put them in when the roof was on the observatory, but I needed the floor in place to anchor the 4x4s that will hold the top frame.

In my last post, I mentioned that putting in the 4x4s presented a challenge.  Here's why:



The corner earth anchors sit about a quarter inch above the level of the floor. I'm not sure why Arrow designed them this way, but it's the only solution that will work with a roll-off shed (the other anchor system has a cable to runs through the roof rafters.  As you can see, we had to cut the floor in the corners and I thought I would have to cut the 4x4s to allow for the anchors.  However, a few blows with a hammer was enough to flatten them down (!) and we were able to mount the 4x4 corner braces successfully.

Below is a pic of the 4x4s in place:


The metal braces work well, but they are a little springy(which I knew going in).  They will be further reinforced by 45-degree 2x4s attached to the 4x4 and the floor.

The final pic shows what part of the completed frame will look like:


I had planned to mount a horizontal 4x4 by screwing it to the vertical timber (it's just laid on in the pic above) and also by screwing it to the screw holes in the top frame of the wall (where the roof would normally attach).  However, on further thought, I think I will make the top frame from 2x4s (which I will probably brace in a couple of places--a kind of stud wall).  This frame will attach on three sides (back and 2 sides); the door frame prevents mounting on the front wall. I will mount 2 12 foot 4x4s on the sides as the tracks for the roof castors. This solution will be more solid and will give me greater wall height for the scope.  I'll fit a weather board from the roof frame with cutouts for the rails on the rear of the roof.  I'll also put weather boards on each of the other sides, which should give the observatory a nice, finished look.

NOTE:  I can't take all the credit for the ideas in this build.  I relied on many sources, but most prominently the posts of 'tulit' on the Cloudy Nights forums, and also the Linnhe Observatory pages.  Thanks to everyone who (knowingly or unknowingly) contributed to this project!

Saturday, July 28, 2012

Observatory, Part 3

Great progress today!  The walls of The Walnut Ridge Observatory are now up.  This is a long post, so please click on it to see it all.  Click on individual pix to see more detail. 

While Arrow sheds are great conversion "kits" for rolloff roof observatories, they are very flimsy in the initial stages of building.  Arrow tells you to start and finish on a calm day.  Here in my part of Indiana, it's rare to have no breeze at all and on the hilltop chosen for the observatory, there's a stiff breeze all the time.  My son-in-law Nathan and I started the walls the morning.  It was very breezy, but we found a good solution, as the pic below shows:

We used chairs to brace the panels inside and outside (they were tightly sandwiched).  Without the chairs, the walls, which are about a tenth of an inch thick, would have whipped around and been destroyed. Some people have had significant problems building these sheds (mostly misaligned holes and problematic panels).  We paid particular attention to the instructions that came with the shed that said the base had to be level and square and we had very few issues. Arrow tells you not to anchor the building or put the floor frame in until the building is complete.  We did both because the corner gussets of the anchor set and the floor frame helped to keep everything square.  In addition, if the building had not been anchored, it would have blown away!  It is a lot easier to work on an anchored structure!

Arrow also tells you to raise the four corner panels before you put in the bracing.  We broke this rule, too, and braced each wall as we completed it (the rear wall is braced above). The bracing really helped to steady the walls as we continued building.  Within an hour, the observatory looked like this:

The upper and lower braces are in place and the structure felt remarkably sturdy.  We removed the chairs and continued to build.


 With the door frame up, and all the walls screwed on, the building seems very solid.  Here's a view of the inside:


This shot shows the interior walls and bracing, plus the floor kit and vapor barrier.  There's no hole for a pier, as the scope will stay on its tripod.

In the next phase of building, we'll build a timber frame of 4x4s that will sit on top of the walls.  I need 4x4s as the 14 is a big scope, and the roof will not clear the scope as it rolls off unless the walls are at least 65" high (the walls without the 4x4s are 62"). This frame will be supported by 4x4s in each corner--BUT, that presents a problem--which I'll talk about in the next update.


Wednesday, July 18, 2012

The Claw!


This prominence looks like a lobster claw emerging from the sun (maybe I spent too long in Cape Cod!).  This is a cropped image originally captured by a Lifecam at 640x480, 30fps.  I stacked 400 of 1000 frames.

A Bridge to Nowhere

A spectacular "bridge" on the edge of the sun. This is a single image processed in Corel Paint Shop Pro Photo.

The Blob!





Glowing brilliantly, a blob of plasma hovers over the photosphere, suspended in a magnetic field.  This is a cropped stack of 200 images.

Lots to see!


With AR 1520 now passing out of view, it might seem there's nothing spectacular to see on the sun.  But in H-Alpha, there's always something interesting.  Here's a spectacular prominence putting on a show this afternoonn

Sunday, July 15, 2012

Observatory Part 2

This is a longish post, so click on it to see the whole post, and click on each pic if you want to see full size.  We went back up today to do some more work at the observatory site.  Unfortunately, the ground was way too stony for us to screw in the earth anchor kits for the frame.  I sent my son (Scott) and my son-in-law (Nathan) to buy concrete while I dug 2 foot deep holes in stony soil in direct sun and 90 degree heat.  The result is in the pic below:

And here are some of the rocks I had to dig out--definitely hard work with a drainage shovel--which was all I had:




When they got back, we filled the holes with concrete and poured in the water.  As was the case yesterday, a dry thunderstorm rolled over, but we kept working.  We got the frame anchored, square, and level and then began work on finishing the floor kit.  In the pic below are two proud members of the construction team, Scott on the left, Nathan on the right!  Fine men!




Saturday, July 14, 2012

Observatory--continued...



I began work out at the observatory site today.  This is the frame for the building with the moisture barrier.  The wind was pretty strong and the moisture barrier was blowing around. I'll wait until the floor is secured before I finalize its installation.  It was a real example of Murphy's Law that work had to abandoned due to thunder and lightning after weeks of dry weather.  The storm, however, brought no rain but I had to leave the site--being without shelter on the nighest point in the county was not the safest place to be during a thunderstorm!  The ground is rather stony and it proved impossible to get the earth anchors in place.  I'll try again tomorrow, weather and schedule permitting.

Silk purses, etc.


It's true that you can't make a silk purse out of a sow's ear, and this pic of Saturn proves it.  I decided to try to reprocess the image I last posted from the 14 inch.  Maybe there's a slight improvement here, but overall, there simply isn't enough detail in the original image to make a good pic here.  This is a stack of around 100 frames from a 500 frame AVI. I'm always amazed at how much detail can be pulled out of a bad image by software like Registax.  When you look at images captured just a couple of decades ago on film (which is what most amateurs used), it's astounding how far we have come.  I've even seen images takes with relatively modest scopes that show surface features on Jupiter's Galilean moons!  Who needs space probes <G>?

Friday, July 13, 2012

Construction Begins!


I cut the pieces of wood for the floor of The Walnut Ridge Observatory today and laid them out in my driveway.  I decided to get an idea of scale by rolling out the 14 inch.  I am so glad I got a 10x12 building kit as opposed to a 10x8 or 10x10.  As you can see, the 14 takes up quite a chunk of real estate.  I'll have room for my desk and equipment, but that will be about it. A pier would certainly take less room, but as I have a tripod, I'm using it.  In the finished observatory, the tripod will pass through the floor and rest on dirt (well, actually, the vapor barrier).

Thursday, July 12, 2012

AR 1520--Again


I tried to be more exacting on the focus in this capture and it's a little more heavily processed.  There's a definite increase in detail, but also in some sharpening artifacts. The big problem here in Indiana is seeing conditions.  With high humidity and temperatures in the mid-90s F, the sun looks as if it is under turbulent water in the eyepiece. Focusing is more inspired guess work than anything else.

AR 1520 Up Close and Personal


This is my best pic of AR 1520 yet; it looks almost like a shield volcano.  This was a stack of about 400 images. Captured in Sharpcap, stacked in Registax 6, and processed in Corel.  Tracking of the PST was manual, using the slow motions on my modified equatorial mount (see an earlier post for details). Cam was Microsoft Lifecam.  Notice how much this area has changed even over a few days of imaging.

Wednesday, July 11, 2012

AR 1520 --Swirling Chaos


AR 1520 captured today under somewhat better seeing conditions than yesterday. Pretty much the entire, 200,000 mile long "archipelago" is captured in this image.  This region is now capable of producing X-Class flares.

Tuesday, July 10, 2012

AR 1520 and edge prominences


AR 1529 and some edge prominences. This  image gives an idea of the size of this large spot group.

AR1520


AR1520 is a huge spot group capable of producing M-Class flares.  This pic was made from a 400 image stack (PST + Lifecam) with some fairly heavy processing (you can see some of the artifacts in this image). It gives a good sense of the energy swirling around in this large group.

Saturday, July 7, 2012

The Usual Suspect


I realize my deep sky "gallery" is a little on the skimpy side and this image does nothing to add to the variety. This is another pic of M13 taken last night with the 14 and a Nikon D40.  I only managed to get 2 decent, 30 second exposures.  The other images displayed what I call "bounce."  That is, the stars look like small dumbells.  The effect is caused, I believe, by the bounce of the DSLR as the mirror flips up during exposure. The night was perfectly still yesterday, so I was hoping for better results.  I've tried other DSLRs, too--notably the Canon Rebel XTi, but they all had more bouncing than the Nikon, which appears to be the best in this regard. The image is a long way from perfect, but it is a big improvement on the image I captured last October.

Dramatic effects of seeing


This image was taken with the 14 inch last night.  The seeing forecast for Indiana  predicted good to excellent conditions.  I noticed significant scintillation even on stars like Arcturus, which is currently close to the zenith.  Compare this image of Saturn taken with the 14, with the image taken with a 5 inch scope in Cape Cod and you'll get a good sense of just how important it is to have good seeing conditions for planetary imaging (something we rarely have here in Indiana, unfortunately).

Friday, July 6, 2012

Big Filaments


Filaments are prominences seen from above.  The image above shows some of the biggest filaments I've seen since I got my PST a little over a year ago.Filaments are held above the sun by magnetic loops.  They consist of relatively cool, dense gas and hence look darker against the hot photosphere underneath. When filaments collapse, usually due to instability in the magnetic field that supports them, they may produce significant flares (called, "Hyder flares").

Prominence Flames


Activity on the sun seems to be increasing daily.  I took this single-exposure image this afternoon; the sun's disk is deliberately overexposed to enhance the detail in the prominences. The air temperature was 101.4 F and the heat index over 104.  The laptop kept shutting down due to overheating.  Seeing was much better than of late, so there are some compensations to the heat!

Wednesday, July 4, 2012

"New" PST mount


I've been using the PST on a Manfrotto camera tripod.  It works well, except it's hard to "drive" to particular parts of the solar disk for imaging.  I was digging in the garage today and I found my old (over 30 years) manually-driven equatorial mount for a 60 mm refractor.  I cleaned off the cobwebs and set it up.  The tube ring is too wide for the PST (but the locking is on an adjustable screw, so there is some latitude on tube size).  I tried wrapping the PST tube in cloth, but it was too slippery and the scope slipped down in the ring.  Then I found an unused packet of insoles for running shoes. One side is of a soft material, the other a nonslip rubber.  I wrapped the PST with it (rubber side to the scope), put it in the mounting ring and adjusted the locking screw until it was tight.  The result is in the pic above.  The mount is a little more wobbly than the Manfrotto, but it is easier to move the scope to desired areas on the sun's disk; tracking in one plane using the slow motion control is also easier than fiddling with 2 planes on the Manfrotto. You may also have to adjust the orientation of the PST, as parts of the mount block the solar ranger in some orientations.  It's not a bad solution, overall.  I'm sure you can find these old scopes and mounts in garage sales for less than $25, so this might be a solution for anyone on a budget who wants to track equatorially.  You can also see the modified Lifecam in a shorty barlow in this pic.

July 4 Fireworks!


This image shows a "bridge" running between two prominences on the edge of the sun.  There was lots to see on the sun today:  huge filaments, crackling active areas, and the gushing fireworks of prominences.  Here in Indiana, we're not allowed to set off personal fireworks due to the extreme heat and dryness (the heat index was over 100 degrees F when this pic was taken!), but with displays like this on our star, it's hard to be disappointed!

Tuesday, July 3, 2012

Swirling Chaos


Here is one last pic from today's imaging session.  It shows the swirling chaos of gas around AR1515.  The wonderful thing about H-Alpha imaging is that you get to see the sun as a "living" star. The individual spots in this image are several times the size of earth.  The fact that earth would be a tiny dot in this maelstrom gives a vivid idea of the real power of the sun.

Huge Filament



A huge filament near to the edge of the sun, with a couple of prominences.  This image was captured during this afternoon's imaging session under very poor seeing conditions.

AR1515 with Prominence


Captured this afternoon, this image shows AR1515 looking very active, with an edge prominence.  Seeing was horrible.  Weather conditions were 90s with a very unstable, shimmering atmosphere.

Monday, July 2, 2012

Cookin' With Gas!


Solar activity is picking up, with close-to-X-Class flares erupting from AR1515.  The image about shows extreme brightening on the sunspot group on the right; this is possibly a flare in progress.  Unfortunately, I'm back to the summer haze and cloudiness of Indiana again, and this image was taken in very hazy conditions.  The weather clouded over soon after this capture (PST + Lifecam).