Phone astrophotography

 Phone cameras have come a long way and are inching closer to the capabilities of DSLR and mirrorless cameras when it comes to astrophotography. Improvements in sensor technology and built in post processing features such as HDR, stacking and star alignment being have made them into a useful backup or even a viable replacement for traditional cameras, especially when used with a tripod. These days, I find myself using my phone more than my DSLR for milky way photography.

The photos that follow are some of my favorite shots of the milky way and landscapes taken using an iPhone 14 pro, on tripod with the maximum 30s exposure in the built-in camera app, and later edited in Lightroom mobile. 

The above was taken at Lerderberg State Park Victoria aiming directly at the zenith around the end of winter. 

These two photos were taken in Point Lonsdale lighthouse. The red light from the lighthouse lit up the surrounding rock formations in red as seen in the top image. What is also interesting is that the second image would not have been possible on a single exposure on a DSLR, as the light from the lighthouse would have washed out the image. It appears that the phone has automatically stacked images of various exposures to create a composite image.

These images were taken at the Gravity Observatory in Perth. While a lot of stars are visible the image contains a lot of noise highlighted during the edits, possibly showing the limits of phone night photography.

The first two phots above were taken at Lake Tyrell, and third at the town of Sea Lake. In the second image, the moon illuminated the surroundings and overpowered the stars, but I was able to capture the reflections of a few stars on lake's calm surface. 

 

These two images are the latest ones taken at Aireys Inlet beach. The last one is my favorite so far since it highlights the details of the milky way as well as the rock formation. I used the flashlight from another phone to briefly light up the rocks while the image was being exposed for 30s, and in my opinion it resulted in perfect exposure of both landscape and the stars. 

While phone cameras have made impressive improvements and deliver impressive results, DSLR and mirrorless systems continue to advance in their own right. Still, smartphones offer unmatched accessibility and portability - and as the saying goes, "the best camera is the one you have with you".

Southern lights in Victoria

It's usually not easy to catch a glimpse of Aurora Australis, the southern lights, from Victoria. Tasmania and New Zealand are better places to be. The occasions when it is visible from in Victoria, it's best seen from the southern coasts of the state and usually appears as a faint glow to the naked eye. My last post on astrophotography had a picture of the southern lights taken from Flinders. But with the intense geomagnetic storm yesterday auroras were expected to be visible from many parts of the world. 

As soon as I got to know this I looked for the closest southernmost point, and being in the west of Melbourne, this was Kirk Point in Point Wilson. While driving there I was amazed to see the green and pink shifting columns of light to the naked eye while still on the highway, and stopped to snap a few pictures as soon as I took the exit. Afterwards we went to my intended location and was treated to the spectacular southern lights show. It waned off around 11pm but was still visible even from my backyard after reaching home around midnight. 

Some pictures are below:

More blue water - why is the Nil Diya Pokuna blue?

On my last visit to Sri Lanka, I was keen on exploring some lesser-known attractions and decided to visit Nil Diya Pokuna (නිල් දිය පොකුණ) located close to Ella in the Uva Province. I was impressed and fascinated by the massive underground cave complex and the blue water pond at the end of the 850m hike through the cave. This was the second time I saw clear blue water in Sri Lanka, the first being in a limestone quarry.  

The usual reason for ponded water to appear bright blue or turquoise in colour is the fine particulates that selectively scatter light through water (the same reason why the sky is blue). In the case of the limestone quarry the fine particulates are minute calcite crystals and in the case of glacial lakes they are finely ground rock particles known as glacial flour. 

Nil Diya Pokuna has a very interesting geology, with several different rock types present around and within the caves, and I wanted to understand what gives the water its blue colour. Caves of this scale are usually formed by the action of weathering and erosion of sedimentary rocks such as limestone. However, this region of Sri Lanka consists of primary of metamorphic rocks. This blog post by Dr Jayasingha describes the geological origins of the cave complex containing Nil Diya Pokuna. According to it, the caves have been formed by the initial dissolution of Marble, which leads to weakening of rock joints and bedding planes and subsequent collapses of the other rock masses creating the large underground caverns. 

Marble is formed by the metamorphosis of limestone, and its dissolution would lead to the release of calcite crystals. There are stalactites formed at several places within the cave, as seen in the photos below, that confirm the occurrence of marble or limestone dissolution. Therefore, it is reasonable to conclude that the reason for the blue coloured water in Nil Diya Pokuna is the calcite crystals that are accumulated in the water as it flows through the joints and fissures in rock containing marble or limestone before making its way into the pond. Below are some photos from my visit:

Stalactites in the cave indicating marble or limestone dissolution
 

Evidence of weathering and staining in the rock

Visible bedding planes and smooth joint surface of a possible collapse leading to cave formation

Blue water and more stalactites

High water levels were blocking off some more expansive areas of the cave

The water was a little murky due to recent rains

More pictures looking to the heavens

Back in 2017, I wrote a post on beginner astrophotography as I was just getting into the hobby. It was mostly a collection of my very first Milky Way pictures that I took at the time. Since then I have been taking more pictures of the Milky Way, and some occasional pictures of the moon, planets and the aurora. So here's an update of my latest selected pictures in the same format as last time, with details in the caption.

This picture was taken at Cape Schanck, one of my favorite places to capture the stars. It's a single exposure with light painting, so the staircase is out of focus. 

One of may favorite pictures taken under perfect conditions. Moon was out on the opposite side of the Milky Way to illuminate the landscape perfectly. Location: Flinders

This is the first picture in which I was able to capture the reflection of the stars in water. Location: Lake Eildon. 

The daytime moon captured through my telescope. I attached the camera into the eyepiece of the telescope with a lens adapter. 

Two photos of Jupiter and Saturn also taken from my telescope. I recorded a short video and processed it using PIPP and AutoStakkert to create these images. Haven't done planetary imaging since, but I do hope to try it out again sometime soon. 

A photo captured from my balcony one evening showing earthshine on the moon. 

The rising moon captured using a telephoto lens without a tripod. 

My first attempt at capturing star trails. This is a single exposure taken over approximately 12 minutes. Photo taken at Lake Eildon. 

This is my first attempt to capture the Aurora. The pink glow is the Aurora Australis seen from the Southern Coast of Flinders. 

This picture shows the recent lunar eclipse- the blood moon, as seen from Flinders shortly after sunset on 8 November 2022. 

More turquoise water

Back in 2014 I was fascinated by the bright turquoise water that emerged from a base excavation at the Aruwakkalu limestone mine in Sri Lanka. I was doing my undergraduate internship at the time and was so intrigued that I researched into the phenomenon and wrote a blog post explaining how the turquoise colour emerges due to selective scattering of light caused by calcium carbonate crystals. A picture that I took was also featured in the Mining magazine. Four years later I came across the striking turquoise water again.

I am currently a visiting research student at the University of British Columbia, Canada and recently visited some glacial lakes in British Columbia. I got to see once again, the bright turquoise colour that intrigued me 4 years ago. The reason behind the turquoise colour is the same selective scattering of light. This is caused however, not by calcium carbonate crystals but by glacial flour/rock flour, which is the name given to very fine rock particles generated by glacial erosion, and remain suspended in the water. The lakes I visited were the three Jofrre lakes and Garibaldi lake, where I even went for a relaxing swim. Some pictures that I took at the lakes are below.

Upper Joffre Lake

Middle Joffre Lake

Garibaldi Lake

Garibaldi Lake

Turtles at Chaaya Tranz

The coral reef in front of Chaaya Tranz Hikkaduwa, formerly known as Hotel Coral Gardens is one of the best preserved coral reefs in Sri Lanka and is a perfect spot for snorkeling. Lots of colourful fish and turtles can be seen close to the shore. Despite fears in the early 2000s that the reef was shrinking, it is in good condition today. Especially when comparing it with the reef in Beruwala which has deteriorated considerably, Hikkaduwa still has a variety of healthy corals and reef fish in abundance.

On my recent visit to Chaaya Tranz, I got to see some of the familiar reef fish and turtles that I saw when snorkeling there a couple of years ago. The types and numbers of fish have not decreased. There were hundreds of colourful fish including a lion fish. Unfortunately I did not have an underwater camera to take pictures of the fish. But the turtles came wandering towards the shore in search of food, and I was able to take plenty of pictures of them.

Hopefully this place will remain as it is in the future. It is important that relevant authorities take required measures to prevent actions such as illegal sand mining which could harm this reef, in order to preserve it for future generations.

Ballooning in Sri Lanka

Recently I got an opportunity to fly in a hot air balloon over Dambulla. Having traveled only in mechanized aircraft such as aeroplanes and helicopters before, this was a different and an interesting experience for me. Hot air balloons are one of the simplest modes of flight and it is because of this simplicity that it is such  a unique and wonderful experience.
The method it works cannot be simpler, The air in the balloon is heated using a gas burner, Hot air is less denser than the surrounding air, so it creates lift. You can only control the force of lift in a hot air balloon, that is by varying the heat given to the air. Where you go is out of your control. It depends on the direction the wind blows. This is why hot air ballooning is considered a sport rather than a mode of transport.
Balloon flights are usually scheduled early in the morning because the air is still and calm at that time. During later hours of the day the increasing temperatures give rise to thermals-columns of rising air that can interfere with the balloon and make maneuvering difficult. (Interestingly, thermals that hinder a balloon flight are the essential ingredient in gliding(which I'm awaiting to try out) where the force required to stay airborne is provided by thermals.) Therefore the morning is the best time for ballooning, besides  the sunrise seen from a balloon is a sight to behold..
Once airborne the balloon drifts away until you decide to land. Landing is done by allowing the heated air to escape by opening a vent at the top of the balloon by means of ropes and cables. Just like any other air sport, a smooth landing demands skill and practice.

heating the air to inflate

straightening the balloon

just before takeoff

sunrise

the gas burner

shadow of the balloon

opening the vent to land

Saruketha - A Sri Lankan Experience

Located in Kurunegala is a uniquely Sri Lankan restaurant named "Saruketha". Staying true to its name it has a refreshing, Sri Lankan village type atmosphere. A lot of attention has been given in creating that place, from the thatched roofs to the ambient music being played through perforated clay pots..They have a menu with a wide selection that is not restricted to Sri Lankan cuisine. The food is not exceptional although its unique surroundings and atmosphere makes it a worthy visit. However, the thing that grabbed my attention most is this funny weather forecast sign displayed at the entrance..

Weather Forecast

Seafood Bliss - Sea Fish Restaurant

Sea Fish is a restaurant dedicated to serving good seafood dishes. Its location behind the Regal cinema in a secluded corner in the Colombo city it helps to maintain the calm and quiet ambience of a good restaurant. They serve a wide selection of seafood main courses out of which my favourite is "Cheese Batter Prawns". They also have some decent Crab dishes as well. The quality of the food and service is considerably better than some other restaurants claiming to serve seafood. It is definitely worth the sea food lovers attention.