Wednesday, January 29, 2014

More Mercury!

Coming back home from work, I was disheartened by the buildup of high thin clouds to the west.  Mercury is putting on a great show in the evening, and as an amateur astronomer, I'd always rather it be perfectly clear.  But as I've said before, clear sunsets are a little boring, and sure enough, we had a beauty as the sun hit the horizon.  Of course, at that "first" sunset, the sky was too bright to see diminutive Mercury, but 40 minute or so later, we had a "second" sunset - the thin clouds that were still around were showing all the beautiful subtle colors from earlier, now needing a longer exposure.  Of course, that is what was needed for the innermost planet too.  At left is a 2.5 second exposure with the 17-85mm kit lens set to 73mm focal length at F/6.3.  Tough to see in the small image, clicking on it will load a full-screen size and Mercury as well as a few stars pop out. 

Those stars hold my interest as on Friday night (31 January), Mercury is at greatest elongation from the sun.  In addition, the very thin crescent Moon will be a few degrees away, and for a bonus, the most distant planet Neptune will also be a bit above Mercury in the same narrow frame!  Now it was almost 11 months ago I caught Comet PanSTARRS and the Moon next to Uranus.  In the picture above, if you look at the full-size image, the 5.5 magnitude 38 Aquarii (about as bright as Uranus) is a little above Mercury's 11 o'clock position.  Neptune is fainter still and might be a tough catch, though I'm going to give it the college try.  Check here to see if I succeed!

EDIT: A pretty sunset tonight (Friday, 31 January), but way too socked in with clouds to try for the triple conjunction.  Though the moon won't be nearby the next few days, I may still try for the Mercury/Neptune conjunction...

Tuesday, January 28, 2014

Dawn's Early Light...

It takes a lot for us to get up before sunrise...  We're natural night owls, usually heading to bed around Midnight, sometimes later.  As a result, we usually rise about 8, long after the sun clears the horizon.  But with Melinda's regimen of radiation twice a day, we need to be at the hospital by 8am, requiring getting up at the (for us) ungodly hour of 6:30 to allow time to feed the livestock (cats), litter box chores and showers.  Fortunately we're only a few minutes from the hospital, but still...

This morning, after a warning of a Moon-Venus alignment from  Andrew Cooper's blog last night, when we cleared the bed, I grabbed the camera and stepped outside to document the morning crescents.  They weren't as close as I was hoping, but the moon next to Venus was quite pretty.  I took the wide shot at left encompassing both, then moved the zoom lens to the maximum of 200mm and cropped tightly for the shot at right.  The star just below the moon is 21 Sagittarii, a moderately bright star above the Teapot asterism, standing out here only because it is so near the moon.  Just to prove it could be done, I also shot Venus at 200mm - the tiny crescent of it still detected, indicating the planet's phase could still be seen in binoculars...

Tomorrow morning the moon will be on the other side of Venus - we'll be up again, so maybe you'll see it yet again here!

Monday, January 27, 2014

More on Focus Stacking!

First of all, let me apologize in advance because the weather in Tucson is spectacular.  I know that large portions of the country are in the deep freeze - no doubt if we were at our place in Chicago we would be bitching about how cold it was.  The local weather here in Tucson pointed out that today Tucson was 100F warmer than the current wind chill temperature  in Chicago!  And while the rest of the country is getting affected by the Arctic Vortex, or Alberta Clipper, or whatever the phrase of the week is, that same weather phenomenon is causing our temps to be about 10F to 15F warmer than average.  We've hit 80F recently while normal are in the mid 60s...

That being said, about the only thing blooming in our yard is the Rhus lancea tree, African Sumac.  Triggered by the warm weather, it has a subtle fragrance, and though it has an unremarkable flower, is thick with them this Winter.  The view at left shows a small branch full of the blossoms.  I say unremarkable because visually they look pretty blah, but in search of a blog post, I dug out the macro yesterday and wow - they are pretty cool close-up! 

In order to get a reasonable image of the microscopic flowers, I practiced the technique of "focus stacking" some more, something I've posted about twice now.   In brief, what you do is take multiple images from a tripod, and perform slight focus changes between the frames.  In macro imaging, depth of field is quite limited.  While stopping the lens down to small apertures you can increase the depth of field, it also increases diffraction noise in the image from small apertures, so while more of the image can appear to be in focus, sharp focus is more elusive.  With Focus Stacking, you stick to moderate apertures little affected by diffraction, and blend together only the sharp sections of each image with Photoshop.  At left is one of 8 frames I took of a sprig of the Rhus lancea flowers.  The central, yellow part of the flower is quite small, only about 1mm diameter, with the entire flower about 2mm diameter.   I took 7 others in quick succession with minimal focus shifts between with the focus knob.  Serious macro photographers have a geared stage for microscopic motions, but this is what I did.  There are several (free!) tutorials on the Internet, assuming you have a version of Photoshop less than 5 years old or so.  The tutorial I used is by Tony Northrup, who does a good job of explaining things and leading this neophyte through the simple Photoshop steps.  The image at right shows the result of focus stacking the 8 frames, all the little blossoms are now in focus, not just a few located in the shallow field of view of the left picture.

It isn't till you look at it at the highest camera resolution that you get a true appreciation of the power of this technique.  Since I'm limited to images 1600 pixels across, lets look at something like the full camera resolution.  At left again is a small part of one of the 8 images, showing one or two flowers in focus.  At right is the same section of the focus stacked frame.  Not only are nearly all the flowers and buds in sharp focus now, but a multitude of sap-sucking aphids, that I was actually looking for visually but not seeing, come into plain view!  I can certainly see using this technique pretty often in my future macro imaging!  The sharp-eyed among you might notice in these and the above pictures that some flowers seem to have 4 stamens per flower and some 5.  I went back with a magnifying glass to find out which it was supposed to be, but can confirm that the number is indeed, 4 OR 5...  Anyway, fun stuff - try the technique and I'll bet you like it!  More of this as Spring develops!

Thursday, January 23, 2014

The "Sun-ny" Side of the House!

Living in the desert, you get used to drab colors.  Except for short periods in the spring when wildflowers or cacti are in bloom or some greens during our rainy season, it is boring earth tones seemingly all the time.  Perhaps that is why we've both become fans of Talavera tile and pottery.  Their bright colors and designs just bring smiles to our faces!  When it was time to redo our guest bathroom, we did it around Talavera colors and tiles, and searched out a sink with the pattern as well.  We love it, and most all of our visitors do too.

True Talavera is supposed to be from the state of
Puebla, Mexico, and made only by certified workshops.  It is very popular along the Arizona/Mexico border where tourist trade flourishes, and while you can get everything from knickknacks to Talavera pigs, lizards and pots with the distinctive patterns, we've taken to collecting sun faces shapes.  Pretty much every time we cross the border and visit our friend Margie in Puerto Peñasco , we head down to one of the stores that specialize in such things and pick out a new one as souvenir.  I don't know or can't tell if they really all come from Puebla, but we love the shapes, designs, colors and patterns.  While the painted glazes are one of a kind, hand applied, even the mass-produced identical pottery faces all come out differently.  Fortunately, new designs come out more often than we go to Mexico for a visit, so there are always new shapes to choose from, and we've never had to get a similarly-shaped one with a different pattern.  We've taken them to hanging them from the south-facing wall of our house and can enjoy their combined glory as we hang out in the back yard.  The one shown at upper left is our largest at over 2 feet (60cm) in diameter, the others a more normal 12 inches or so.

And while we usually go shopping ourselves to chose a design and verify we don't have the pattern, the ones at lower right of the wide view above are special.  We got the pair of them from Margie herself as Christmas presents.  Shown at close-up here, you can see some of the fine details of each, and even though their casting shape is identical, their individuality comes from the hand-painted glazes, as they are quite different.  We love them and you will note we are leaving room for future additions to the family!

Wednesday, January 22, 2014

Mercury in Evening Sky

The evening twilight is a little less lonely!  While Venus departed for the morning skies a couple weeks ago, finally the innermost planet Mercury has popped above the western horizon to keep early evening observers company.  It reaches greatest eastern elongation (18 degrees from the sun) on 31 January, so should be easily observable for the next 2 weeks during late twilight in the WSW.  The photo shown here was taken with the 70-200 zoom at 70mm for just under a 1 second exposure at 6:30 local time, about 40 minutes after sunset, and is a very good approximation to the naked-eye view.  Mercury is likely the least-observed of the naked-eye planets, so now is your chance to get out and look for a moderately bright star above and left of where the sun set.  You should have a good view of the western horizon for best results.  Good hunting!

Tuesday, January 21, 2014

Change in Plans!

Just 24 hours ago I updated Melinda's upcoming treatments.  Of course, as soon as we've got things penciled into the calendar, everything gets upended!  The start of her radiation treatments has been moved up a week to day-after-tomorrow, and her "rumored" chemo treatment cycle has been scheduled for next week the 27th, 28th and 29th, sandwiched between morning and afternoon radiation treatments.  Monday will be a challenge - typically her two drug infusions take upwards of 5 or 6 hours, so sandwiched between two radiation treatments, it will be a long day!  I think the patient is ready, eager for this next round to get started - the sooner we get started, the sooner we'll get done!

Monday, January 20, 2014

The Path From Here...

We have Melinda news!  When her chemo ended over a month ago now, all we knew were generalities...  There was talk of radiation, but nothing beyond her PET scans scheduled for the New Year (3 January).  We saw her oncologist Dr. Garland a week later and got good news - radiologist report says: "near-complete metabolic response of the primary tumor and para-tracheal nodes and complete metabolic response of the pancreatic lesion"!  With that, Dr. Garland handed us off to the radiation oncologist Dr. Yi, and in the last 10 days she's had a brain MRI (completely normal), and she also had a chest CT to layout a coordinate grid, complete with tattoos to position her upcoming radiation.  The CT, while not as sensitive to cancerous tumors as a PET scan, showed no signs of cancer, said Dr. Yi...  The photo at left shows the patient today with some flowers she recently received.

She has enjoyed the last 5 weeks off from treatments, just diagnostic scans, but that is about to end as the radiation treatments start in 8 days on the 29th.  It sounds pretty aggressive - 2 treatments a day (early morning and late afternoon) at UMC (about a half hour each) for 5 days a week for 3+ weeks, then full-brain radiation for a couple weeks after that to zap any microscopic cancer cells that may reside there, since the chemo she's received doesn't pass the blood/brain barrier.  There is also talk of one more cycle of chemo after all the time off she has enjoyed.  That will likely happen just before or concurrent to the start of her radiation.  Hopefully, around the time of her birthday (15 March), ALL treatments will be finished and she'll have something to really celebrate!

Saturday, January 18, 2014

More Moon...

In the last post, besides illustrating the size difference in the moon between its closest and furthest point, I also talked about the subtle colors of the moon.  I mentioned that color-enhancing the mosaic from the Celestron 14" didn't work - evidently the mosaic software made minor color changes to blend together the frames of the composite.  Well, I went through and reprocessed the frames, enhancing each of the composite frames before assembly, and it seemed to work better...

While it worked better, it still isn't perfect!  As shown at left, the 6-frame mosaic (each composed of 5 stacked frames) appears to have color gradients in them, but other than use a smaller telescope to take a full-frame image rather than a mosaic, not sure where else to go with this...

At least the above is slightly better than the version I mentioned before, where the color saturation is turned up on the assembled mosaic.  While I cranked it a little extra to show the "paisley" background pattern, you can see it is obviously wrong too, picking up subtle color changes from the mosaic software.  There are some agreements with the above frame, but there are some issues with the lower center section of the mosaic.  As noted in the previous post, color differences represent differing chemical abundances.  The blue color especially indicates a higher concentration of titanium...

While easily showing up by cranking the saturation in Photoshop, any of the color variations are tough to pick up visually.  But I'll keep trying and try to get some more uniform and repeatable results...

Thursday, January 16, 2014

Part-Time Lunatic!

So what is an amateur astronomer hungry to do some observing to do when it is at or near full Moon?  Well, I guess that it is time to look at the Moon!  Normally it is absolutely the worst time to observe it - not only is it extremely bright, but also with the sun directly behind us (on Earth), nothing on the Moon casts a shadow.  As a result, there are not many fine details to be seen - only differences in albedo (reflectivity) can be discerned.  But there are a few things that are of interest to see, even when full!

Shown at left here is a picture of the Moon with my Celestron 14" telescope 2 nights ago - the night before the full moon.  Now realize that the C14 has a 4,000mm focal length and the entire orb won't fit in the field of view.  Those following the blog lately know that isn't a problem - I have the Microsoft ICE software that will easily assemble a set of pictures into a mosaic.  That is what this is - a 6 frame mosaic, with overlap on each to make assembly easier.

What I had planned to post about is color on the moon.  While the above picture looks like it is B&W, it is, in fact, a color picture.  Visual observers will tell you that color is really subtle on the Moon, and it doesn't show in photos either.  However, you can see some differences - especially in the Sea of Serenity, the dark area just right of center above in the mosaic.  Shown here at left is that part of the frame, but in Photoshop, the saturation is cranked up a bunch.  In this one you can easily see color differences.  What causes it?  Well, it is generally known now that the "seas" on the Moon were caused by asteroid impacts, and the color indicates composition differences, likely from different chemical abundances of the asteroids that caused them.  Most striking in this frame is the blue color of the Sea of Tranquility, which indicates a higher abundance of titanium, compared to the orange tint of the Sea of Serenity at upper left with less titanium.  I had planned to process the upper mosaic the same way to show the color differences, but the mosaic program evidently makes subtle color shifts - I got the prettiest paisley color charts when cranking up the saturation on it!

The other thing I read about the full Moon yesterday (the 15th) was that it was a "tiny" full moon.  Though you rarely think about it, nothing in the solar system orbits in a circular orbit - all planets and their moons move in elliptical orbits, and it happened that yesterday's full moon happened with the moon near its apogee - the furthest point of its orbit from Earth.  Interestingly, I recalled about 20 months ago that I photographed a "Supermoon" taken near perigee (closest point of its orbit).  The image at left is a full Moon at each time with the same telescope (a 5" Celestron) and same camera, cropped in half and assembled next to each other at the same scale.  The date and distance from the Earth's center is noted on each, and you can easily detect the approximately 14% change in diameter caused by the Moon's elliptical orbit.  While 14% sounds like a lot (about 1/7th), in practice, it is difficult to discern very accurately without instrumentation.  Similarly, the Earth's orbit around the sun is elliptical too, though only by a few percent.  Interestingly, we are closest to the sun in January, the middle of northern hemisphere Winter!  Obviously, the Earth's season's aren't driven by distance, but rather the tilt of the earth's axis!  Perhaps a lesson for another day...

Wednesday, January 15, 2014

John Dobson Dies at 98.

The sad news came late today - the passing of John Dobson at 98 years of age.  We go back a long ways, though not sharing a particularly close relationship...  I'm glad to know he recognized me when our paths occasionally crossed, not just one of the adoring throngs to rub elbows with him at appearances.  We first met 33+ years ago on my first trip to the Grand Canyon in June of 1980.  As a fresh-faced new hire at Kitt Peak, I ran into the little dynamo of a man leading that early version of the Grand Canyon Star Party.  I even stood in line for the better part of 45 minutes to look through a 24" telescope whose design now carries his name - a Dobsonian.  I'm not sure I'd ever gazed though one before, but not only was the telescope design unique, but also the idea of sharing the view of the universe to inspire the public.  He and his small band of companions spent their entire summers travelling to the western national parks because that is where the people and pristine skies crossed paths and he wanted to grab them by their lapels and make them look.  At left is that 24" I peered through, and at right, 20 years later, John makes Canyon visitors look at the sun.

About 10 years after our first meeting on another trip to the Canyon, I learned that no, he wasn't doing the star party any more, at least at the Canyon.  He had angered religious fundamentalists by saying in his twilight talk that "we are all evolved from pond scum", and he was "invited not to return".  Well, upon asking, with the Park's permission, I was allowed to restart the Grand Canyon Star Party, now in what, its 24th year.  After a few years, he returned to the event and reveled in his celebrity there.  Of course, giving the same slide show he gave 20 years before, I cringed when he firmly stated that "we're all evolved from pond scum"!  This time we weren't shut down...  That trip, in 2001, he was escorted by Jane Houston Jones, and documented in an article "Four Dobs and a Dobson" she wrote for the San Francisco Sidewalk Astronomers.  The pictures are taken from that trip and are courtesy of Jane.  In those versions of the star party, buddy Margie Williams (yes, the one with the house in Mexico!) was making buttons for us to wear and John was so proud to have one marked "founder"!

John has lead a most interesting life.  Do read his Wiki entry at left.  Arguably, the development and popularization of the large-diameter Dobsonian telescopes have had the biggest effect in amateur astronomy of the last 60 years!  While less-well-known, his advocacy of astronomy outreach has also had a large effect on the public, especially for us in Arizona who continue the annual Grand Canyon Star Party for a week every June.  While living a full and interesting life, it is still sad knowing that he is no longer with us advocating for everyone to LOOK UP!

Sunday, January 12, 2014

Whitewater Draw 2014!

Yesterday saw us finally getting to Whitewater Draw for the first time this Winter.  We've been there and posted many times, and is always a fun day trip for us, about a 2 hour drive to the southeast of Tucson.  It is amazing that the high desert of the Sulfur Springs Valley can host such an amazing variety and number of birds, especially the sandhill cranes, which winter here after migrating down from northern Canada.  We announced our intentions to the astronomy club last weekend and had 7 people in 3 cars meet us there.  I understand that last year they had some issues with irrigation pumps, with some of the ponds bone dry, so it is always a bit of a surprise what you will find there.  But it looks like all is well, there was a goodly amount of water in all the ponds, though a distinct lack of plants, so not a great food source for smaller waterfowl.  We were gratified that there was a good supply of cranes though...

A couple of our group were there for the first
time, and it is always fun to see it through their eyes - I think they were impressed!  We got there about 2:30 and stayed until well after sunset, perhaps 4 hours.  There was a good initial supply of cranes, but not particularly close to the viewing stands, perhaps 75-80 meters away.  I was ready for that by packing in my William Optics 11cm F/7 refractor (770mm focal length) telescope, which zooms in on them pretty well.  The disadvantage, of course, is that it is manual focus, and with birds there just isn't time to use live view for critical focus for every frame.  But by carefully using live view and making sure the adjustable diopter lens on the viewer was set properly, I got a good percentage in decent focus - perhaps 40% or more on non-moving targets.

Because at the "near" distances involved, the telescope provides a pretty shallow depth-of-field.  One bird might be in perfect focus, but one right behind or in front might be blurry with the 700+mm focal length.  I like learning new techniques and methods, and as I posted a week ago, I learned about focus stacking to improve depth of field.  Multiple images are taken at different focus settings and the images blended in Photoshop.  As shown here at left, a single image shows some birds in sharp focus, but those behind are quite blurry.  In this case, I took 4 frames in quick succession while racking the fine focus slightly.  Blending them together in Photoshop provides the image at right with a better focus range.

Similarly in this shot of a single bird, while it is in sharp focus, I wanted the reflection in the water, the bird and the stalks behind all in focus.  Taking 3 images at various focus accomplished it.  There are some artifacts in some of the blends, especially in high-contrast areas near the crane necks in the image in the preceding paragraph.  I'll need to get more experience to see if it can be minimized, but it isn't too objectionable...

I shot a couple things besides cranes - here is buddy Bernie who came down with us on his first visit to Whitewater.  He got a new Canon 6D the other week, so was having fun with his new camera system.  When he got far enough away I could focus on him with the WO telescope, I snapped him.  At right is a long-billed dowitcher, which we saw in Mexico a couple weeks ago, and I think we've seen it at Whitewater before too.

Always up for a good challenge, catching the cranes in flight with the telescope, especially when focusing manually, seems to be a nearly impossible challenge.  But that didn't stop me from trying.  As it neared sunset, the cranes that were in the shallow water mostly departed for nearby fields for some late-afternoon feeding, providing lots of chances.  In the fading light, mostly guessing at focus, panning along their path, if you can catch the iris in their eye, you must be living right!  The only unfortunate thing is that the wing position is identical in both of these...

Sunset came and went, and the birds stayed away
- visible in hay fields a couple miles to the west - thousands and thousands of them.  Only a few hundred remained anywhere near us, at left visible silhouetted against twilight colors in a multiple-frame panorama.  We waited, knowing that they would eventually return.  Whether their delayed return was due to the warm temperatures ( at near 70F, I think it was the warmest I'd ever seen there in January!) or perhaps because of the nearly full moon, I don't know, but finally nearly a full 45 minutes after sunset, with nearly all hints of the sunset gone, their increasing rattling calls finally signaled their return.  The western sky filled with their hordes, though it was too dark to do much with the cameras.  For this last exposure I switched to the kit lens, shot at full zoom of 85mm for a tenth of a second. 

Our intrepid band of observers caravanned to Tombstone where we rejoined for dinner at the Crystal Palace, finishing our meal just as a LOUD band was starting to play.  It was a nice way to draw a great day to a close...  We'll try to get down again before they leave in another month or 6 weeks.  It is always a fun trip on a slow weekend!

Saturday, January 11, 2014

Finally - Conjunction Day!

I feel like a slacker, missing a blog post yesterday - first day not posting since last year!  Melinda and I travelled to Phoenix last night attending the Saguaro Astronomy Club's monthly meeting.  They had a great speaker, Stephen Levine from Lowell Observatory talking about commissioning the 4.3 meter Discovery Channel Telescope in Northern Arizona.  Polished at the Optical Sciences Center at the University of Arizona, I happened to mention it this week to Norm Schenck who did a lot of the work on the mirror there, and fortunately he was interested enough in "his" scope to come along and hear about how the project is going.  We didn't get home till 2am, but was a great time!

Today (Saturday), friends Donna and Bernie came down from Phoenix to join us in our first trip of the year to Whitewater Draw to check out the cranes.  More about that trip on another post, but on the way out of town, since both are amateur astronomers, I twisted their arm into stopping by the Mirror Lab to look for the planet Venus, passing through inferior conjunction between Earth and the Sun today, only about 5 degrees north of our star.  To make the observation easier, we observed from the shadow of a "tall" building, in this case, where I normally park at work in the shadow of the building.  That way, while searching near the sun there was no chance of sweeping across the brilliant disk and risking eye damage.  Since Venus was due north of the sun, it was a relatively straightforward matter to step upwards and locate it, though we found that binoculars absolutely had to be focused on infinity to spot it.  But we all finally saw it, Bernie at left is locating it in his 200mm telephoto, and I centered it in the William Optics 11cm F/7 triplet APO (770mm focal length).  After taking a few exposures, Bernie mounted his camera on the scope and did the same, shown at right.

Of course, it is a tripod-mounted shot, non tracking, but the exposure shown here is only 1/3200 second at F/7 and ISO 200 so tracking wasn't needed.  I used a time delay with mirror lockup to minimize vibration.  The image shown here is at full camera resolution.  At only 5 degrees from the sun, it was something less than half of 1% illuminated, so it couldn't be much of a skinnier crescent.  Some folks wonder what is blocking the disk of Venus, why does it look this way?  Well, like the moon, it goes through phases, and when it moves between the Sun and Earth, we are mostly seeing the unilluminated side of the planet.  It would have been nice to get it at a larger scale, but would have required a bigger scope and tracking mount - perhaps at the next conjunction in a year and a half!

Thursday, January 9, 2014

Countdown to Conjunction!

Two days to Venus' inferior conjunction when it is closest to the Sun!  Fortunately, it passes about 5 degrees north of the Sun this time as opposed to actually transiting the Sun's disk last time...  The extra few degrees makes it easier to spot in twilight too - I was able to spot it tonight when thick clouds cleared late in the day!  I again observed from our cul-de-sac's mailbox where I'd spotted it recently, this time I set up the William Optics 11cm F/7 triplet refractor, so effectively a 770mm lens.  Melinda took a snapshot of me as I was taking a couple images - mounted to a tripod where I used a timer to take pictures vibration free - using mirror lockup and a 2 second delay to minimize shaking from the mirror.  I like to have the tripod set to my height to minimize discomfort when doing observations like this. 

I first spotted it in binoculars - it wasn't until the sun dropped below the Tucson Mountains before the sky dimmed enough to spot it, but once seen, it was pretty easy to see in binocs and telescope, though I forgot to look for a naked-eye view!  Tonight's image is shown at right, and is shown at full camera resolution.  With the crescent as low as it was, it is not a great image, but it is what it is!  Turns out it was taken right at the moment of actual sunset at 5:37 local time.  I've got plans for tomorrow night, but may well try to shoot Venus again at high noon on Saturday, the day of inferior conjunction.  I've observed Venus during inferior conjunction before, but with a go-to scope.  With the 5 degree separation it should be easy to set up in the shade of a building to do the observation on conjunction day.  Watch this space!

With the waxing gibbous moon in the sky, it was easy to take a snapshot for a comparison of size.  The image of the moon is at the exact same scale as the Venus shot above.  Venus appears to be about the size of some of the above-average craters...

Wednesday, January 8, 2014

More Venus!

Since last spotting Venus 2 nights ago, I figured I was done with the evening apparition, as it is rapidly heading towards inferior conjunction on Saturday (11 January). Last night (Tuesday) I got home late, but it was cloudy anyway. Tonight I got home moments before sunset, about 1730, and immediately grabbed the binoculars and went where I had spotted it Monday - our cul-de-sac's mailbox. Even though the sun had just dropped below the Tucson Mountains, and a band of clouds lined the western sky, Venus was easily picked up in virtually the same position as Monday, though about 15 minutes earlier. I had time to fetch Melinda and she saw the huge near-ghostly crescent in the strong twilight-lit sky. I didn't run for the camera as it looked virtually identical to the earlier shot. While Melinda observed with the binoculars, I convinced myself I could see it visually - telling her where it appeared, with her confirming. Moments later the layer of clouds swallowed it up, but it was so cool to see it so close to inferior conjunction - only 3 days away! I may even try again tomorrow, and for that matter, since Venus is pretty far north of the sun this conjunction (don't forget it was 5 June, 2012 when it transited the sun - the last inferior conjunction!) I might find a safe spot to try to observe it on conjunction day where the sun will be blocked... The key to finding it in strong twilight like tonight is having a reference point and knowing where to look - thank goodness I spotted it while getting the mail Monday night!

And for the first time ever, I've observed something that was simultaneously in the SOHO LASCO C3 coronographic imager! I've looked in the past without luck, but Venus entered the field of view the last day or so, shown here at left.  For those of you who have never seen these images before, the Solar and Heliospheric Observatory (SOHO) has been keeping an eye on the sun since 1996!  The C3 image shown here has a 15 degree field of view with north up.  The dark disk blocks the bright sun, the little white circle marks the position of the sun.  The bright object upper left is Venus, which is moving towards the west (right) past the sun.  The fainter one at lower left is Mercury, which is moving away from the sun and will be visible in a week or so in our evening sky.  The radial streaky bits are some of the outer reaches of the Sun's atmosphere, the "snow" is the detector reacting to charged particles ejected from an ejection from the sun a day or two ago. 

Normally there are stars and constellations visible, but they are a little overwhelmed by the particles in the above image...  Here is an image taken a couple weeks ago from 26 December - just about the time we got back to Tucson from our recent Mexico trip.  With less solar activity you can now see what I meant about seeing stars.  This time of year the Sun was transiting Sagittarius, most commonly recognized by the Teapot asterism at the bottom of the frame (only top part visible).  Even though the camera is pointed towards the sun, you can see the bright parts of the Milky Way, as well as some of the brighter Messier deep-sky objects like the Lagoon and Omega Nebulae, as well as star cluster M22.  Mercury was beyond the sun, still chugging eastward below the sun.  It really seems strange to be deep-sky observing from this remote platform with the Sun in the field of view!  It has served as an invaluable observing aid for watching planets nearing the sun, and more recently, of Comet ISON disintegrating as it rounded the sun on Thanksgiving...

Tuesday, January 7, 2014

The Power of Pixels!

Unfortunately, the parade of posts from our 3-day stay in Mexico comes to an end.  Amazingly, counting the prompt to observe Venus featuring the pic from Puerto Peñasco on 27 December, I squeezed 9 what I think are all pretty good posts from the 1200+ images taken on that trip!  So currently I'm on empty - who knows what will come along for the next post...

I've been having fun the last few months since being turned on to the Microsoft ICE program.  The software (free download!) does an amazing job stitching together random image assemblages to make a mosaic or panorama.  Gigapixel panoramas are quite popular, with several software companies vying for customers.  I paid 99 euros for AutoPano Pro a few years back, but couldn't get a new copy with my old key when my hard disk crashed recently, so I moved to the ICE program, which does what I want for the most part. Of course, the advantage of taking multi-image panoramas is that you retain the native resolution of the lens used for the individual images, but build up a wide-field of view by combining them.  More pixels are good!

While down at Margie's beach below her house, I took a 16-frame panorama with the 70-200 Canon zoom, set to 200mm.  I didn't use a tripod like I should have, but did use a monopod to help steady the telephoto and help in aiming.  All frames were oriented vertically to maximize the vertical extent, and I provided a reasonable 25% overlap between frames for the software to stitch them together.  Very quickly the ICE software slapped them together into the panorama shown at left.  Well, I should clarify - the program made a panorama that was 25,000 pixels wide (108 million pixels!)...  Unfortunately, Blogger limits pictures to 1600 pixels wide, so the image displayed when you click the thumbnail is only about a 20th of the original...

Slightly better is if I limit the downsizing a little and put them side by side as shown here.  You get a better feel at a little larger size.  It is so fun to scroll around the image at full camera resolution.  It is the whole reason to shoot these panoramas with a telephoto lens - keep the resolution of long focal lengths, but build them up for a full wide-field image.  The right image shown just about the only defect in Microsoft ICE's assembly - through no fault of their own, since the waves moved between exposures, there is no way to have a perfect panorama.  There are 2 seams in the image if you load the full-size image.

About the best way to get a feel of what it is like to stroll through the image is to look at a couple full-resolution images.  These pictures are full-size crops from the above panorama, and you can get an idea of what is capable looking at the full image.  Again, realize all these images are from the same 16-frame panorama...  Fun stuff!  I just wish there was a way to better enable you to see the full-size images.  I guess I would need a real web site for that, plus the image would be about 12MB in size too...  Any suggestions, let me know!

Monday, January 6, 2014

Last Evening View of Venus?

Five days from inferior conjunction of Venus, when it passes between us and the sun, and I almost forgot to go out to look for it tonight.  Fortunately, 20 minutes after sunset, it was visible just over the tree line from our cul-de-sac, and I got a brief glimpse of it.  Even with the 70-200 zoom with 1.4X converter, the crescent was easily visible in this cropped view.  You might have to click to load the full-size view to see it better.  For this shot the XSi was used for 1/250 second at F/6.3. I'm thinking it might be visible, but not for much longer!  In another 10 days or so it should be visible in the morning sky where it will stay through most of the year, not to return to the evening until about Thanksgiving!