Saturday, September 1, 2012

Intermediate View

The Lassen trip resulted in one CCD image - the area around Sadr, the "center" star of the northern cross.  I knew before I started that this wouldn't be the finished product (are astro images ever truly "finished"?).  You see I forgot the wheel with my narrowband filters at home. So I wasn't able to shoot any Ha (Hydrogen alpha) which would have really made these dust clouds pop.  So I imaged with Luminance and Red, Blue, Green filters only.  At least I have a head start on the color channels for the next dark moon cycle.

In a couple weeks I'll be on another multiday dark sky outing when I can really do this field some justice.  Stay tuned!

Intermediate Image

Taken at Lassen National Park, CA  August 17-19, 2012
QSI583, Canon EF 200mm f/2.8L
Luminance: 12x5min bin 1x1 @f/2.8 & 12x5min bin 1x1 @f/4  2hrs total

Red:  12x5min Green: 1 2x5min  Blue: 12x5min  all bin 2x2
Total exposure time 5hrs
AP900 Mount
calibration, registration and post-processed in PixInsight

Tuesday, August 28, 2012

Observers at the Edge

Here's an image of my posse at the recent trip to Lassen Natl. Park.  Beset by smoke and clouds for days we were treated to an exceptional sky on our last night.  From this vantage point in the parking lot it looked like we were perched at the edge of the earth - looking out into the vastness of space.  The Milky Way had that sugary texture one sees in very dark skies.  Inky dark lanes run throughout.  So remarkable to us and yet only a few generations past were skies like this commonplace for most peoples on earth.
The "teapot" pouring star clouds right down the barrel of that Schmidt-Cassegrain
Two observers using the large Schmidt-Cass (one at scope, the other hidden at right using charts).  One imager huddled over laptop with his refractor illuminated by the glow of red LEDs.  My gear is hidden in the background but you can see my laptop silhouetted against the horizon.

We often have to remind each other to take our eyes off our equipment and just - look.  All too rare and never enough time to let the experience soak in.  That's why we have to go out and do it again.  And again.

Observers at the Edge

Taken at Bumpass Hell parking lot, Lassen Natl. Park,   August 18, 2012
Canon T2i (stock), Canon EF-L 24 mm @f2.0
Manfroto Tripod (stationary), set inches off the ground
Composite of two frames, one focused on stars, one on 
Each exposure 10s @ ISO 3200
vignetting and lens correction in Lightroom 4
Composited in Photoshop
final adjustments and noise reduction in Pixinsight

Thursday, August 23, 2012

Star Fire

A dark sky outing with friends to Lassen National Park in Northern California was hampered by two large forest fires in the area.  For multiple nights we dodged smoke and clouds for a glimpse through to some of the darkest skies California has to offer.  Finally on Saturday night, August 18, the smoke and clouds had abated and we drove up to the Bumpass Hell parking lot full of anticipation for a night of imaging and observing.

As we entered the Park an ominous white cloud billowed high in the West.  A new fire had started from a lightning strike only a few hours earlier.  As darkness fell the eerie glow would presage the dangerous fire that it would become over the next 48hrs.

The conjunction of Mars, Saturn and Spica (lower left) in the fiery glow of the Ponderosa Fire.  
Click on either image for a larger version where you can toggle the annotation.
The Ponderosa fire is still burning - nearing 25,000 acres with up to 50 homes and structures burned.  Evacuation warnings have gone out to the little town of Mineral where we stayed.

The fire glow over the ridge died down with the coming of night and we enjoyed a nearly perfect night of observing.  It was a very narrow window as I am sure the smoke from this fire has darkened the skies over Lassen again.

Star Fire

Taken at Bumpass Hell parking lot, Lassen Natl. Park,   August 18, 2012
Canon T2i (stock), Canon EF24 mm f1.8
Manfroto Tripod (stationary)
Mosaic of 4 frames, each 8 sec exposures @ ISO1600
no dark or flat subtraction
vignetting and lens correction in Lightroom 4
frame stitching in PTGui Pro
final adjustments and noise reduction in Pixinsight

Thursday, August 2, 2012

Pleiades Rising

Trying to make the best of a trip to New Mexico during the full moon and monsoon season.  Don't get me wrong - the skies are spectacular.  I'm just haven't learned how to best capture what I'm seeing and feeling.  I have plenty more day shots that I like but haven't decided if I want to "cross the streams" on what would otherwise be a astronomy centric blog.  If I did it would increase the rate of images I post given the glacial pace of astro-imaging this year.

Here come the Pleiades again.  click to enlarge
The moon is two days shy of full and is swinging low on the horizon about 30 degrees outside of the right side frame.  The full width is about 170 degrees but the above image is a little less than that since I cropped out my shadow which was on the left side of the frame.  Only the brightest stars are visible because of the short exposure and moonlight.  You can see the Pleiades rising just above Kitchen Mesa, the large rock face in the left hand frame.

I experimented with a number of ways to capture/process this.  It is a two frame mosaic with each frame processed with 4 different exposures using Photoshop's HDR function.  I certainly do wish for more tools in the PS HDR module but at this point I don't do enough HDR to justify a specialty package.  I stitched the two frames using PTGui Pro since PS couldn't figure out how to stitch this correctly.  After that I did some final tone/exposure/noise reduction in Lightroom.

Pleiades Rising

Taken at Ghost Ranch, NM   July 31, 2012
Canon T2i (stock), Canon EF-S 10-22mm @ 10mm  f3.5
Manfroto Tripod (stationary)
two frames, each frame with 1, 2, 4, 15 sec exposures @ ISO1600
no dark or flat subtraction
vignetting and lens correction in Lightroom 4
HDR combine in Photoshop
frame stitching in PTGui Pro
final adjustments and noise reduction in Lightroom 4

Sunday, June 17, 2012

Venus. Done. Now give me some deep sky!

With eclipses, transits, and other astronomical events of note behind us I'm returning to my first love.  Wide field deep sky imaging.  But I really should post at least one picture of the transit before continuing.  I'm still going to work on assembling the time-lapse but haven't had time for the frame by frame alignment required.

Venus in mid-transit.  One of 298 frames.  Movie adaptation to be released...later.

It has been too long since I've really adorned the hair-shirt.  I've missed the unique pain of sleepless nights with endless hours fighting optics, weather, and electronics problems, followed by more hours of processing.  I'm not the most efficient (far from it), accomplished (light years away), or clever imager but I hope some other poor soul starting off can gain some measure of assistance by reading of my accounts.  Or at least a chuckle at my multitude of travails.

I always seem to bite off more than I can chew and this upcoming project will be no different.  The benefit of wide field is the variety of objects that can be captured.  It allows for greater creativity with framing.  But sometimes even a single wide frame isn't enough and that's where a multipanel mosaic comes in.  I've only attempted one two panel mosaic previously so why not make it harder by going for six?

A close friend encouraged me to post progress along way.  Too much focus on the finished product he says.  He's right ... accomplished imagers already know what is involved.  If things work out well you end up with a nice image with no one is the wiser of the struggles to get there.  As the title of of the blog implies - imaging is hard work.  Don't let anyone tell you otherwise.  The pros only make it look easy.  A tribute to their skill honed from thousands of hours of focus.  The rest of us need to bumble along ... but oh what fun!

So.  Posts to follow will chart the journey of this mosaic.  Warts and all.

Taken in my backyard in San Jose, CA  Jun 5, 2012 7:00pm PST
Canon T2i (stock), Canon EF 200mm f/2.8L + Extender EF 2X III @ f8, Baader solar filter

AP900 mount
1/800 sec exposure @ ISO100
post-processed in Lightroom 4, Pixinsight (colorized to my taste)

Sunday, June 3, 2012

Goodbye Venus ... till Tuesday

After yesterday's successful capture of the crescent Venus I decided to try one last time.  Planetarium software shows Venus about 3.75 degrees away from the Sun this morning - and should be safe to image.    After making absolutely sure the sun was outside of the frame I removed the Baader filter and snapped off a sequence of exposures.  The keeper was at 1/3200sec ... a little faster than yesterday.

Goodbye Venus ... see you in silhouette on Tuesday

You can readily see the large gradient from being so near the Sun.  If there were a second frame adjacent on the right side the Sun would be in about the middle.  I think we can safely say that Venus is lost in the glare now ... we'll have to wait until Tuesday when she does her once a century glide across the solar disk.

Taken in my backyard in San Jose, CA Jun 3, 2012, 10:51am PST
Canon T2i (stock), Canon EF 200mm f/2.8L + Extender EF 2X III @ f8
AP900 mount
1/3200 sec exposure @ ISO100
post-processed in Lightroom 4 and PS5

Saturday, June 2, 2012

Venus revealed: T-3days

This morning I took a couple more images of the sun to verify exposure conditions and then thought about Venus, unseen in the glare of the Sun, racing towards her date.  But is she really unseen?  

I checked planetarium software and it shows Venus is currently about 5 degrees away from the Sun.  The field of view of my camera with 200mm and 2x telextender is about half that in the long direction so in theory the Sun should be outside the field.  Could a picture be had?

Keeping the solar filter on ... I slewed to the position of Venus and verified that no part of the Sun was visible in the frame.  Then off with the filter and took an exposure series all the way to 1/4000 which is the limit of the T2i.  Focus was kept the same as when I was imaging the Sun so if Venus was in the frame I should see it.  In the glare of daytime I couldn't see anything on the camera back but once inside I could see Venus quite clearly in the fast exposure frames. 

Three days before "new" Venus

Since we are only 3 days before transit when Venus will be directly between Earth and Sun only a slight sliver of a crescent is visible.  Pretty neat!  

Tomorrow, exactly 24hrs after this image Venus will be 3.75 degrees from the Sun.  The apparent motion is now about 1.75 deg/day (about 3.5 moon diameters).  With care it might be possible to get another picture tomorrow morning.  After that it will be too close and lost in the glare of the Sun ... at least for my gear.  Still it is pretty neat to see her one last time before she reappears against the disk of the Sun on Tuesday afternoon.

Taken in my backyard in San Jose, CA  Jun 2, 2012 10:30am PST
Canon T2i (stock), Canon EF 200mm f/2.8L + Extender EF 2X III @ f8

AP900 mount
1/2500 sec exposure @ ISO100
post-processed in Lightroom 4

Friday, June 1, 2012

Transit Practice

With excitement for the coming Venus transit this coming Tuesday (June 5) I ordered me up a Canon Extender EF 2X III to double the focal length of the 200mm lens.  As I learned from the annular eclipse the image scale (for the sun) with the 200mm is pretty meager.

I took the following picture yesterday and while the sun still doesn't fill much of the frame it is more than  adequate for my transit purposes.  All I really want is a record of having lived through it and if all goes well assemble an image sequence into a movie.

Here is the full frame with the T2i.

Ol' Sol

I took that image, brought it into Pixinsight for enhancement and colorization.  Here is the result after a heavy crop.

Detail visible after processing in Pixinsight.  Please click for larger size - it's much nicer.

Focusing is a challenge ... in full daylight it is difficult to see the camera screen.  Autofocus does work but I'm not absolutely certain if I could improve on that with manual focus or not.  The above was focused manually using the buttons on the control box for the robofocus.  While it was the best of the lot it a moment of good seeing could easily account for the improvement.

Taken in my backyard in San Jose, CA  May 31, 2012
Canon T2i (stock), Canon EF 200mm f/2.8L + Extender EF 2X III @ f8

Baader solar film over lens cap
AP900 mount
1/640 sec exposure @ ISO100
post-processed in PixInsight

Tuesday, May 29, 2012

Eclipse Movie!

I had the Canon T2i / 200mm EF-L (with Baader Filter on the lens cap) ticking off an image every minute during the annular eclipse this last May 20.  The camera had 140 images on it by the time the sun set behind the eaves of the house.  I focused as well as I could by hand on sunspots but they were pretty tiny at this image scale.

When I had a chance to look at the images I realized I was in for the same spot of trouble I was in for the lunar eclipse movie.   Each time the scope was re-centered the image would obviously shift in the image frame.  This means they all required alignment.  I still don't know of any better way to do this than by hand ... there are no stars in the field to take advantage of normal image registration software.  

So each frame was lovingly nudged into alignment by hand (in PS4).  All 140 of them.  Then cropped in Lightroom, exported as jpgs, and finally sequenced into a movie with Quicktime 7.

It looks a bit nicer if you view it at youtube so you might want to click the link.  At the very end you can see the sun setting behind a tree and finally the edge of the roof cutting it off for a premature end.

I chose to run the movie at 10 frames per second so the motion seems smooth.  The whole clip is only about 14 seconds!  Almost 2.5hrs worth!  And of course much more than that to align all those frames! Ah well ...  I've done worse for less.

The Baader filter gives a neutral white light image.  I noticed many of the images and movies out there are colorized - on purpose or due to the type of filter used.  They are rather more dramatic but I chose to keep any artificial flavorings out of the mix.

It was a good dry run for the Venus Transit on June 5.  I learned I really don't have enough image scale at 200mm and if I don't use the refractor I'll have to get a tele-extender.  Experiments underway!

Sunday, May 20, 2012

The Hairshirt Goes Social

The Eclipse of 2012 was probably the deepest I'll see in my lifetime - without travel that is.  Part of me was wishing I'd made the 3-4 hour drive to see the full eclipse but it was still pretty impressive from my backyard in the San Jose area.  We had some some friends and neighbors over for a BBQ and in the end it was a wonderful way to enjoy the eclipse.

I set up with my 80mm AT-LE refractor and 12mm Nagler with a Baader filter on the front. An hour before the event I realized that with so many guests it would be best to rig up a projection.  I quickly taped a piece of white paper to the bottom of a cardboard box and then fastened the box to the ball head on my tripod.   Off came the Baader filter, and after some focusing and moving the box to and fro a very nice image presented itself.  The full solar disk about 8" in diameter.  Multiple sunspot complexes were easily visible with the lighter grey penumbra easily visible on the largest of them.  So many sunspots made the eclipse just that much more interesting.

Eclipse equipment with "spokes model"
I had the Canon T2i clicking away a picture every minute through the 200mm lens.  This was a very good dry run for the Venus transit since I learned that I'll definitely need to borrow a friends (you know who you are pal) 100-400mm.  The disk image is just too small at 200mm.

Even so, I'll attempt to assemble a time lapse of the eclipse event - if for no other reason than to practice up for the Transit on June 5.

As written in a post below, the practice of imaging is largely a solitary pursuit.  With other imagers nearby it can be a shared experience but in the end it is just you, the camera, the mount, the computer, and a horrible tangle of wires and cables.

Sharing the eclipse, live, with nearly 20 onlookers was great fun.  The youngest was 18 months, the most senior over 90.  It was satisfying to share something so unique with a group of friends.  Yes, the hairshirt monk does go social every once in a while.

But there was another aspect.  A more intiment moment of sharing.  One that I wouldn't trade for pinpont stars across the field.  Or for the lastest gear.  Or a set of perfect Flats, darkest skies, deepest image.  It is the moment of connection with another over this instance of wonder.

Today's connection: mid-eclipse

 It's when another looks at an image, or through a telescope, or even with naked eyes at a dark sky and gets it.  It's when another sees what I see and there is the ah-ha moment.  Doesn't happen frequently but when it does it makes all the hard work of imaging worthwhile.  I was thrilled that it happened today.