Sunday, May 6, 2012


Sometimes you can't argue against the hype - sometimes you just gotta join in!  So even though explaining that all the hoopla about the "supermoon" doesn't amount to much more than a hill of beans, I decided to go out last night join the throngs to check out the rising moon right at sunset.  Even stopping at Circle K for a Thirstbuster I overheard folks talking about it - jeez!  Melinda had to work, so I was on my own for this adventure...

I went to just about the only place in metro Tucson with a great horizon - "A" Mountain.  It sits about a mile SW of downtown, and about 500 feet above the local terrain, providing great views from about due north, through the east to due south.  I arrived about 45 minutes before sunset, lots of space yet, parking near the stone wall that lines the road at the peak, leaving just enough room to set up a tripod and run the telescope from the side door of the van.  I'm still "interviewing" telescopes to use for the solar eclipse in a couple weeks, and tonight I was trying out a William Optics 110 triplet APO I'd gotten years ago.  I used it a few times, but was depressed by how bad the corners were - need to invest in it's special field corrector.  Tonight I used a generic .8 reducer/flattener that works ok.

While waiting, I took the opportunity to see what I could see with over 700mm of focal length from such a fine vantage point.  Naturally downtown and the UA area were right at my feet, figuratively speaking.  Since I work at the Stadium (under the east stands, invisible from the west), I took a series of shots that resulted in this mosaic.  Blogger only allows images 1600 pixels wide, not the 9,000+ of the mosaic.  The full resolution pictures were quite impressive at the field center.  The stadium, almost 3 miles away showed impressive detail.  The signs posted in the stadium were readily resolved.  Did the UA really play in a football bowl game called the "Salad Bowl" in 1949?  The sign sez so - full resolution just below!

It is challenging to orient yourself to identify other structures in low-angle shots like these.  For instance, the buildings just to the upper left of the stadium are not on campus - that is Catalina High school, more than another 2 miles distant (fortunately I could read the sign on the full-res image).  The buildings on the upper right of the frame is Tucson Medical Center more than 5 miles behind the Stadium.  Distance certainly gets compressed with long focal lengths.

Fortunately, I practiced with the telescope earlier in the afternoon at home.  While a sturdy mount and tripod were used, images are still degraded by the "mirror slap" in the DSLR.  I've developed a workaround - enable the mirror lockup as a custom function, and use the 2 second timer delay.  When using a cable release or intervalometer, as soon as you push the button the mirror swings up, then 2 seconds later, the shutter fires making the exposure, but meanwhile vibrations from the mirror motion has died out and sharp photos are the result.  I did the same thing for the moonrise time lapse with the timer set for 5 second intervals.  I would have gone for 4 if I could have, but I'm not sure the camera finished writing before starting the next exposure.  I didn't want to clog anything up, so kept it at 5 second intervals...

Other views caught my eye - the Tucson police helicopter buzzed us once and was visible around town, so snapped their photo from a couple miles distance. 

The I-10 underpass at Granada has an interesting color pattern - ROYGBIV!  The colors red, orange, yellow, green, blue, indigo, violet is the proper order of colors in a spectrum.  It was interesting to see it demonstrated on an underpass - perhaps a connection to the optics industry here in Tucson?

I think one of our prettiest buildings here in Tucson (I am loathe to call it a skyscraper at 330 feet tall and 23 floors) is the UniSource Energy Tower.  Though not well received when it was built in 1986, it is a blue-topped buff colored building, meant to match the colors of the clear-sky topped mountains that ring Tucson.  It has been through a couple owners over the years, but believe it or not is the tallest building between San Antonio and Phoenix! 

While beautiful in daylight, the subtle ripples in the glass turn it into an orgy of reflected color at night when observing from a distance.  Other than a lone employee working a Saturday night, the picture shown here at full resolution is to illustrate the reflected lights off the glass face - cool!

Of course, "A" Mountain is right  next to Interstate 10, which connects to 1-19 headed towards Green Valley, Nogales, and Mexico 60 miles to the south.  A look to the south shows heavy weekend traffic down I-19 with Desert Diamond Casino to the distant left of the frame.

The sun eventually set, and the moon rose.  I wasn't sure where it would appear - the hills shown in the sequence are actually the southern foothills of the Rincon Mountains to the east of Tucson.  So it took a couple additional minutes after moonrise above the horizon to clear the hills shown.  The picture at the top of the post was taken well after it cleared the horizon, when it was not so reddened by the atmosphere.  The time lapse, uploaded to Youtube is below, and you might notice that on one of the frames, there is a helicopter visible!  Just by chance I caught a MH-60 Blackhawk helicopter, no doubt flying out of  Davis-Monthan AFB. 

Looking at the full-resolution image, an amazing amount of detail can be seen, given the exposure of 1/160th second in the rapidly dimming light.  You can see the refractive effects of the exhaust at the edge of the moon as well.  The base was a good 7 miles distant, so optics and camera did well!

So once the moonrise position was spotted, I centered it just left center of the frame bottom so it would rise through the center, and pushed the "start" button on the timer.  I think the exposures started out at 1/250 second, and I made one or two corrections to exposure on the fly.  Once home, I twiddled a lot with the imaged in Photoshop, to increase the contrast a brightness where they needed to be, yet treat all the frames the same so the sequence would be watchable without too much flickering or brightness change.  The results appear here - I'm happy with the result - perhaps real-time video with Melinda's camera would have been preferable, but I hate running 2 cameras and then not seeing the event!

It wasn't till the moon tracked out of my frame that I noticed that the mountaintop lookout had been transformed into a parking lot!  There were no spaces left to park, so people were circling - once someone double parked, the road was effectively closed!  I managed to get out and head home - to cat chores and figure out massaging moonrise pics!

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