Dark sky backyard of Michigan

In 2016 I got my AZ-EQ6. Without a proper imaging set, I did mostly visual observation with my 150 Rumak. In 2017 when the 70SA Gen II was released, I immediately acquired one. This is a compact quadruplet astrograph offering a very wide field of view at F5. Usually scopes this small only corrects for cropped sensor but this one does 135 full frame image circle.

Two SkyRover 70SA with different front AR coating

So in 2017 I restarted my astrophotography journey in June. Because Ann Arbor is so close to Detroit Metropolitan area, light pollution is a problem. Even if I drive 20 minutes to the west to the university’s radio telescope facility, light dome from the Jackson on southwest is still an issue. The best place without going to the north is a small state park called Lake Hudson close to the Ohio State borderline.

Lake Hudson is 50 miles away in one hour drive

My first stop in the sky was the Trifid and Lagoon nebula. This trial exposes some unforeseen issues I hadn’t thought of. For one, the focuser sag gradually drift my camera out of focus as the telescope tracked across the sky. I had initially focused the camera during mount alignment. After target repointing I left the focus unchecked. Composition was another lesson. In pitch darkness, it was very difficult to tell the sky outline from the optical viewfinder. Getting familiar with the position of reference star beforehand would save vast amount of time for actual imaging.

Lagoon and Trifid

Lagoon and Trifid Nebula

During the solar eclipse road trip, I’m getting more familiar with the setup. And yes of course, that deserved a whole new article. But I’ve been too busy and still not satisfied with the data processing. Our team had gotten a treasure trove of data. On the return journey, I took the NGC7000 North America Nebula in the Badlands National Park. It was a perfect spot, absolutely no light surrounding us. It’s probably one of the best dark sites in contiguous United States.

4 hours of exposure at the darkest side yields perfect details

NGC7000 / North America Nebula

One great thing about AZ-EQ6 is you can do two scope side by side

Before the winter storm crawls in, Michigan actually gets a few clear night every new moon phase. The problem to have these over the weekend. Thus I would still pursuit the clear night when I didn’t have a meeting next day. In September I returned for the Cygnus heart and then the Heart nebula after midnight.

The exposure was too short when the clouds rolled in. This is definitely worth a retry and I should also include the soul nebula. For the Cygnus heart region, I did a three pane mosaic and the data still requires processing.


Moving to October, IC1396 Elephant’s Trunk was overhead. At first I confused this target with the Rosette Nebula. It is a much larger region with star nursery in the center. My APS-C sensor could barely cover the entire region. Due to the light dome on the east and the emission nature of this nebula, I kept the CLS filter in. A three-hour exposure of this region revealed lots of detail, let the image speak for itself.


IC1396 Elephant’s Trunk in 3 hours

In December I took the Triangulum Galaxy. The frigid weather made the battery life extremely short. But at the same time there was almost no dark current on the sensor. An hour long exposure left a clean background.

Triangulum Galaxy

In 2018 I also attempted the awesome eye of NGC7293. Now this object is highest in August but still due to the latitude of Michigan it’s close to the horizon and can be affected by light dome.


Another similar planetary nebula is the M57. But this one is so small I have to use the 150/1200 Rumak for help.


At F12 the Ring nebula is still bright. However the hydrogen outer shell requires magnitudes of more exposure.

Before I left, the last target was the M16 Eagle Nebula. For this wide region, Milky Way mixes with the HII emission nebula. Use of CLS filter made color tuning a lot difficult. The entire galactic plane is broadband spectrum.


M16 Eagle Nebula

Now I need to find another spot amongst the light pollution in bay area. The sky is clearer but the city light grows significantly. A year has passed and I haven’t entirely settled down. So I took out my AstroTrac TT320X again. Far away from city light, the Mojave Desert is truly dark!


Check out my 4+ hours long Barnard’s Loop on my AstroBin

The Whitney Challenge

I don’t prefer physical challenges. Yet the Mt. Whitney stood there a very special place. It’s the highest point in contiguous United States. Beyond that, it’s also one of few accessible through a trail. This makes it a huge difference comparing to, say the highest point in China – Everest, where professional mountaineering skill is essential plus huge bucks.

I’ve been tempting to summit this mountain for a while. So back in 2014 when planning a road trip in California, I decided to stop near the lone pine for a distant look on the mountain and get more detailed information. So here it is, a map from National Geography and a picture.



The center is actually the line pine peak, Whitney is right under the flag pole

It wasn’t until I got home that I found out the image was the wrong target. And the Whitney of course is so far way. This gives you a glimpse on the length of trail, a whopping 22 miles round trip! I gradually realized this wasn’t an easy task. Each year, some people got injured along the way or worse, lost their lives here. The complication is partly due to the altitude sickness after exertion. Other times, lack of buddy to overlook each other when accident happens.

In 2016, I met Weichen, a post-doc and an avid amateur mountaineer here in Michigan. This was the perfect chance to accept this challenge. Another big push to me was so much was going on with my life that I just want to forget. In May this year we didn’t get the lottery for an overnight permit. A slot in late July was the only option for two people.

So began our training, I picked a staircase with elevator next to it. And every other day, we set off a 99 floors of simulated hike with weight. Then the next day ran for cardio. The gradual push made me comfortable with even more weights. Three days before we left for Whitney, we peaked at 11 kilometer.

We packed in all gears needed for the hike. For your reference, head light and sufficient battery is critical as you don’t want to get lost in the middle of night or fall off cliff! Trekking poles can be helpful crossing the creek and on the way down. Lastly, don’t forget to bring food, candy and water. On the website it suggests 3 liters per person per day and that really is the minimal. There is water supply along the way if you bring your filtration device. But if not, bring plenty water!

The Great Sand Dunes

Monument Valley

Navajo Mountain and Colorado-San Juan River Junction

Lake Powell, Page, Glen Canyon Dam, Horseshoe Bend and Antelope Canyon

Grand Canyon

At that time, flight to Las Vegas was the most affordable. We arrived the previous day at noon. After getting the car and filling ourselves full with buffet, we headed toward California through the Death Valley National Park.

Badwater Basin


Stovepipe Wells and Sunset

By the time we got to lone pine, it was already dark. We retrieved the permit from a small locker next to the visitor center. Then we immediately checked into motel just to get enough sleep for the hike next day.

Day use permit at Whitney

Sky was clear in high Sierra early next day. We left the motel at 3:30AM before dawn. There was 20 minutes’ drive from lone pine to the Whiney Portal. From there we started the actual hike at 4:15. Just after the third switchback, we encountered the first trouble at the north fork of lone pine creek. Water level was unusually high that made us to trek it through with bare foot. The standing rocks were mostly submerged.

Moon and Venus, looking back down the valley

The trail stayed on one side of mountain for the next half hour of hike until you hit the Lone Pine Lake. The first crossing has tree log bridges. After a while, we hit another submerged section without any bridge. For once more, we took off our boots to cross it.


Me crossing the log bridge near Lone Pine lake

In the next hour, we saw the first sign of snow. The unusual heavy precipitation last winter at California has left so much snow to melt. And of course, the flooding alone the Whitney trail.

Daybreak above the Lone Pine Lake

Alone the route the trees recedes rapidly. After passing the outpost campground below the mirror lake, landscape transforms into barren rock faces. Occasionally, there’s patches of flower scatter between the melting snow.

The traverse is at the top of this huge snow patch

Then we encountered the first challenge. A part of trail completely covered in snow and we don’t have any ice climbing equipment as we didn’t expect this so late in the season. For each step forward, we made sure the trekking pole is deep solid in the snow and the other foot wasn’t slipping at all. I was scared since this was my first time attempting something so steep on ice.

The red arrow indicates the traverse covered in ice

At 10AM we finally arrived at the trail camp upstream of Consultation Lake. As we watched the huge massif and icy slope, chances of making to top at noon faded away in a flash. Altitude had already taken effect on my body when I saw my fingernails starts turning purple. We spent 15 minutes recovering ourselves with water and candy. Then we put on the sunscreen before march ahead to the endless 99-switchbacks that will quickly rise from 12,000 feet to trail crest at 13,600.

Looking back down at the Consultation Lake (right) and the Trail Camp Pond (left)

The last switchback, traversing a 40 degree ice slope

Had I succumbed to the previous scary icy traverse, then I probably wouldn’t have to suffer this near heart stopping endeavor at 13500 feet. After the last switchback, we had to traverse two more continuous patches of melting snow just before the trail crest. OMG! A 500 meter 40 degree slope is waiting for your slip at any single step. I tried not looking down. But at every step, I have to just to make sure I secured my foot at the right place.

Exhausted at the trail crest

This little guy wants my food!

At 4100 meters, I started to feel the pain in my stomach. I know I was exhausted, so was my buddy. But there was no appetite to eat. The weird feeling of thin air here is taking a toll! I essentially forced the lunch into my mouth. With the projected timing, we will at most arrive after 2PM. We dropped some of our backup supplies at the John Muir Trail Junction and we pushed on.

The Hitchcock Lakes in the Sequoia National Park

The final 2 miles to the summit was a completely different experience. Here traversing across the west flank of peaks leading to Whitney, it was dry and hot unlike the icy north slope of the valley we trekked up. For this portion, we were left with a single bottle of water for both of us. So we had to preserve as much as we can.

A final few steps toward the victory!

Oh I forgot, we brought two cans of beer! Cheers!

Finally, we made it at 2:20PM. And cheers! We brought two cans of beer, but only for photography. I sip once cause I knew alcohol would make you dehydrate even quickly. So we just left the other can inside the hut. We log our name into history and then for some serious view!

The highest 360 panorama in contiguous United State

(click for 360 link)

I took a 360 panorama on the top of Whitney, with love. There was absolutely no time to shoot a time lapse. We headed down immediately.

The needles next to the last 2 miles up

Started our way down at 3PM

At the trail crest, I felt we probably would not make it to the top. Now I had a sensation of dying due to dehydration before reaching the trail crest. Half way down, we consumed the last drop of water. It was a race against time until we dehydrate or make it back to the trail junction. There we have 1 more liter for both of us.

Some of the trail section is dangerously close the cliff edge

But to get more water, we would have to make it back down to 12000 feet at the trail camp, where most campers were. So I still have to think about that icy traverse again. We saw some daring climbers slid down the icy slope. That was really a dangerous move given melting snow with low friction and exposed rocks.

As the trail camp got closer, the hope of surviving finally overtook the fear of death. We met someone alone the route who kindly gave us filtered water. The fresh melting ice water was cold, yet so refreshing! The sun already falls behind the massif. We would have to made it faster to get back to the Whitney Portal before it’s dark again.

We skid down the frozen ice of lone pine creek

To conserve time, we follow the fresh trace of others alone the ice on the lone pine creek. We stayed away from the rocks where cracks most often formed. But in the end, there’s a moment we had to get back on the trail when getting close to the snow line. Sunset happened by the time we got close to the Mirror Lake. We got back onto the trail, turned on our head lamps and continued down the mountain.

We followed the river on the way down. GPS record

The flooding was even worse after a day of melting snow washing down in torrent. But this time, we trekked right across the creek. The cold ice actually made a beneficial effect like pain killer to our heating and swelling ankle.

The milky way came out, for the first time I’ve ever seen in high Sierra. It was so clear. With the calm air at high altitude, those stars barely twinkled! I decided to sit down for a five minute rest, just enjoy the sound of nature from waterfalls, insects, birds and the starry nights through the gaps between those tall pine trees.

We finally got back to the portal. Both cellphones battery went dry. Buddy’s GPS watch also stopped recording between the Mirror Lake and the Lone Pine Lake. It was fulfilling feeling after such an achievement. 22miles/36km round trip in snow icy condition without proper gear. It was close to midnight when we checked into hotel. I took a shower and fell asleep immediately when I touched bed. My leg still hurt the second day. That morning, I finished three plates of breakfast while watching sun light shine on the Mt. Whitney.

Sun set behind the Sierra mountain range at Owen Lake

We left the lone pine before sunset. I really need to treat myself with star gazing. Next stop was the Dante’s View over watching the Badwater Basin of Death Valley.

Along the high way, shimmering lights filled the distant void of desert. I wondered, would I one day stand on the top of that peak again or I might never wish to challenge myself with some like this. But one thing was certain, I had just left my lingering love on the top. Good night, Mt. Whitney!

The Milky Way Arch over Badwater Basin

(Click for 360)

Written on Oct 15, 2017

National Park Time Lapse – Tranquility

Since my last astrophotography road trip in California two and half years ago, I really haven’t spent anytime writing on travel and photography. Amidst the camera project and my PhD, I somehow have accumulated a pile of decent photography yet to be processed or released. But anyway, all those hard work serves to produce better images wouldn’t they. So I took a break in the previous weeks to finish off some of those leftover photo work.

Please enjoy my second time lapse compilation – Tranquility

Included are some of the time lapses I took in Big Bend NP, Mojave National Preserve, Death Valley, Picture Rock Lakeshore and Shenandoah NP. Then there’s also the Jiuzhai Valley in Sichuan, China!

In terms of astrophotography, I only got a few left in hard drive for release. The road trips I cover recently were on the east coast. With light pollution and bad weather along the way, there really weren’t many stars to be seen. Let alone for deep space imaging.


Wide Field Milky Way Center shot in Death Valley

As for 360 panorama, it becomes a routine for me now as the pipeline for 3×6 stitching is well established. In the meantime I start to incorparate the floor image in the stitching process.

Carlsbad CavernsThe WindowWhite SandBig BendPorcupine MountainTybee Island LighthouseShenandoahDeath Valley

Mouse over for location, Click for 360 View

The link to my first time laspe compilation is here:

Astrophotography in pure darkness

In Michigan, I could only see one nebula – “Michigan Nebula”. Nah, that’s just a joke in the amateur astronomy society here to complain about the frequency of cloudy nights in the state. For me, the complaint is real. I do not have an observatory for regular imaging. Packing such a heavy weight EQ mount and going to some dark rural site only to find cloud building up is almost frustrating and unacceptable. Now it seems a road trip every half year could offer me better opportunity with the best dark sites in the States.

So here are some examples. During the Christmas of 2013, I went to the Big Bend National Park in Texas. There’s absolutely no light pollution from almost any direction except some desert town outside the park. Terrain should perfectly shade these local glares.

At the dusk we entered the park, but from where we were staying took about 1 hour drive. The surrounding lost its colorful appearance when the last patch of sky became completely black. The headlight of our vehicle and the passing by prevent us from dark adaptation. But when we step out of the car, the brilliant zodiac light immediately catches my attention. It was so bright, even under the streetlight in a parking lot, I could see it reaching 30 degrees high in the sky. The clouds kept me blinded for 1 day and half. It was until the third night that I could view it in its full majesty. Until midnight that day, the zodiac light was still bright on the horizon.

Zodiac Light

Zodiac Light

This time, all the clouds move away to the west and it offered a clear night for astrophotography. I picked a spot near the park entrance to setup my tracking rig, and another camera for time lapse. The Orion’s belt was my imaging priority. In a 2 hour and 40 minutes total exposure, I was able to reveal all the dark nebula and dust bands adjacent to the bright M42 and horsehead.


Meanwhile, the sunset at Rio Grande Village was considered by us to be the most scenic combination after 3 days of lonely drive in desert.


360 panorama – Sunset of Rio Grande

Now 6 months have passed, another opportunity took me to the Mojave Desert in California. This time, I’ve substitute the glass inside the optical glass inside with one having antireflection coating. Thus all the glare surrounding bright stars and nebula center are gone. About 10 minutes’ drive away from the small desert town Baker, I set up my AstroTrac on the sandy road of Mojave National Preserve. It was dry hot at such a low altitude. Besides the intermittent wind blowing against you, is the occasional sound from some unknown animal sheltering in the wasteland. The glare from Baker and head light of passing cars on I-15 are on my north, the Rho Ophiuchi Nebula is a perfect target. Yet under this dry heat, it was exhaustive trying to sleep inside a car. I manage to get 100 minutes of exposure in total.

Rho Oph

The Rho Ophiuchi Cloud Complex

This time I’m using the hacked firmware preserving the raw output from the sensor. Now with custom made calibration pipeline developed, I could achieve perfect preprocessing before the actual alignment and stacking.

Meteor and Milky Way

An occasional meteor captured during the time lapse at the same night. The Rho Ophiuchi gradually sets into light dome from southern California as my TT-320X tracking it. The background light would still impact the SNR in the dark nebula.

Some 360 panoramas along the way, click to pan and zoom.


Devil's Postpile


At monolake, I took a panorama of the sky. But it seems more challenging to process. The sky was divided into 7 areas each 4 subframes. Airglow greatly increases the sky background near horizon that night.


Nature Time Lapse of the World

Since the 2013 road trip I managed to compile and fill in most of gaps in this project – the project I’ve been working on intermittently for 3 years. It’s a time lapse I had started in 2010 when I was caught and shocked by the realism presented by time lapse photography. Those pioneers on Youtube and Vimeo made nature time lapse videos with moving clouds and starry night.

I made a rough calculation and I immediately realized how fast the shutter life will be consumed should I use a DSLR. A 1000 exposures for one time lapse at a interval of 6 seconds. So I started with bridge camera, but this time the image quality and lagging speed greatly reduced the success rate. Finally to only have one camera to work with during travel I started serious time lapse photography. The first series was shot in UK during my internship and I was first amazed by how transient but colorful the nature could be.

Gradually problems began to appear, the flickering issue posed a challenge to correct. Then comes the annoying vibration. Sometimes caused by winds, others by necessary manual control interruption. When more videos were taken between sunrise and set, the exposure control became a serious hurdle to smooth the transit. And worst of all, my physical perseverance to withstand the winds and bitter coldness for one hour.

Rio Grande Sunset

In 2011 the music was chosen and I start to fill in each melody with the appropriate clip. The flicker was vastly reduced with VirtualDub filter. When better clips were available, the entire edition would be moved around and discarded. In 2012 I got my new D7000, the new feature avtive D-lighting was both the curse and bless of photography. On one side it could greatly expand dynamic range for single shot JPEG, on the bad side it introduces extreme flicker between images due to its algorithm treats images individually. People moving around was suppressed with statistics filter with my coding effort. Every times when new semester started it became another down time for me to doubt if I could eventually finish this project.

At the end of 2013 I traveled to the Big Bend National Park in Texas for the final shot. Against all odds, I managed to reduce the light from cars moving by and finished this project. Please enjoy the video. For best effect, use full screen, dim lights and sounds up! If you like it, help me share it so others would view as well.

Technical Detail

Time lapses were mostly taken at 6 seconds interval. To reduce data burden, most were taken at medium resolution. The preprocessing were done at 4K resolution if applicable.

Panning done with AstroTrac pointing zenith. Camera includes D200 and D7000 with Samyang 14mm lens. One shot with Canon 6D.


Grand Road Trip of 2013 – Part 3

Pick up from the previous post, where we left the grand canyon for the wild Utah. Yeah personally I thought Utah itself is a huge national park. From Bryce Canyon to Capital Reef and Canyonlands, it’s almost contiguous wilderness all the way to Colorado.

Yovimpa Point

Panorama From Yovimpa Point

The midday view could not be compared to a sunrise, which shines the canyon from the east. The view all the way down to Yovimpa Point were similar but gradually offers a higher vantage point. It was decided not to drive to far away from where we stayed the night for time lapse photography.

Bryce Canyon Natural Bridge

The Natural Bridge in Bryce Canyon

That night the unusual high level of airglow cast a greyish haze on the starry night. Human could only preceive color in broad daylight when cone cells are functional. With long exposure, the full color is recorded on camera where airglow shines brightly in green.

Airglow and Milkyway

The moonlit canyon was awesome in time lapse I took that night with airglow on lower horizon mimicking aurora. The location however, offers a poor view for the Rho Ophiuchi regions.

The next day we drove across the Capitol Reef National Park and headed directly for the Canyonlands and Arches in Moab.

Green River Overlook

The Green River Overlook

Time was still limited for 2 days in Moab. We only had the chance to view the delicate arch. The delicate arch trail were one of the most difficult in the park. Half way through you would need some rock climbing over the slick rock before reaching the frame arch and the delicate arch.

The Frame Arch

The Frame Arch

Delicate Arch

Delicate Arch at Sunset

I’ve seen nice astrophotography in Arches National Park but it turned out the delicate arch trail are too strenuous for carrying equipment. With the lack of knowledge on where to go on the previous night, we drove to the panorama point to set up the gear.

Road to the Stars

The road to the stars

It turned out the Milky Way itself was bright enough. Should the Moab has less light pollution, the Sh 2-27 H-alpha region would be brighter in the view.

Color Palette of the Stars

The color palette of the sky were more difficult to image, with low altitute on horizon and LP, the SNR was low enough even with LPS-P2 filter.

Grand Road Trip of 2013 – Part 2

Yeah, a busy semester left me with little time to write this trip. But I’ll try to finish it.

The four-corners is indeed the most suitable place for astrophotography. After I got back home, it becomes clear when I looked up the dark sky finder and the monument valley is one of few Bortle Scale 1 dark sites in the US. It’s a shame they had so many spot light at hotel.


Light grey for scale 2 and dark grey for bortle scale 1 excellent sky

That afternoon we actually drove into the park on the sandy and gravel road. An all-wheel-drive SUV is highly recommend even in dry weather like this. And something should never be missed, a colorful sunset at the valley.

Colorful Sunset

The next morning we open up the curtain and witness in awe as sun rises above the distant valley and buttes, right at the doorstep.

Dawn at MV

Leaving the valley behind, the road ahead still challenges as we go into the grand canyon. We planed to make a stopover at Page, AZ for lunch and meanwhile viewing the horseshoe bend and the man made marvel – Glen Canyon Dam.

Horseshoe Bend

The horseshoe bend

I just could not risk another step before falling off the rim. Standing there, it’s utterly silence except the sound of your heartbeat, breath and the circling vulture.

Glen Canyon Dam

The Glen Canyon Dam view from the bridge

Quite unexpectedly, the AZ-89 had a landfall at echo cliffs and we were forced to take the additional 90 minutes detour to reach AZ-64 before climbing onto the south rim of grand canyan.

Grand Canyon Watchtower

The Grand Canyon Watchtower

The previous night’s observation overdrafted my energy, where I ended up photography the milky way in the village. It was until I got the photo that I found a overhead power line ruined my shot… Yet the rising milky way behind the clouds are absolutely gorgoues. The next morning, the sunshines the towering cliff in this way.

Sunrise on Cliffs

Morning light on the cliffs

I still remembered the first time I got here and viewed a sunset at Hopi point.

HDR at Hopi Sunset

HDR Composite taken last year

Foggy Valley

And foggy river valley at twilight

Well that’s just the best memory I had. We left the grand canyon and headed back down where we came and took the AZ-89A northeast to cross the Marble Canyon.


Half way down the 89A I took a 360° panorama of the echo cliffs.Panorama

Click on image above for 360 city interactive panorama

Echo Cliffs and Navajo Bridge

Navajo Bridge and the Echo Cliffs

Marble Canyon

The Marble Canyon

Then it’s climbing up to the north rim again, crossing the national forest and finally arrived at our next stop in Kanab.