Saturday, April 9, 2016

The Near Sky - Daytime Astrophotography




Our bright star, the Sun and a phenomena known as Rayleigh Scatter prevents us from seeing the "night" sky.  The stars are there, something many may not realize, despite our inability to see.  So in a broader sense, astrophotography is not just a nighttime opportunity.   


Our nearby star, the Sun is a brilliant fireball in the daytime sky


 Our ancestors looked at the sky more or less as two-dimensional.  Indeed, many today view it as such until they have their conscience raised by the astounding facts of astronomy and celestial mechanics.  In an artistic sense there is nothing wrong with a two-dimensional sky.  Paintings and photographs render all objects as such.

All the sky is in the eye of the beholder.  The layers of distances (clouds, atmospheric phenomena, planets, stars, galaxies) are stacked upon the view.  Our perspective is simply the results of this stacking.  The depths of distances are integrated to the thickness of a piece of paper.



The atmospheric phenomena, clouds, filter our view of the universe, day and night



These varying phenomena come together on their own.  Our view of the sky, day or night, is an ephemeral happening in constant flux with space and time.  I often spend a day aware of these ethereal happenings.  My tools are my eyes and my cameras.  The obvious tool to participate in this adventure (and it truly is one!) is time.  




Our Sun can be seen visually with the unaided eye (with caution!) through filtering clouds



Whether we are conscience of them or not, all sorts of phenomena are happening.  The sky is the most accessible place to witness this change over time.  There is no need to wait until night to participate.

Perhaps I an overstating the obvious.  Things are always changing.  So what?  Well, maybe it is the influence of Zen on my thoughts and the awareness brought about by meditation.  The obvious seems to be impenetrable to many in our busy world.  

The next time you look up at the sky, remember that the Sun is a star.  It does not "rise" or "set", but the earth turns to make it appear such.  The sky is not two-dimensional, although we routinely see it that way as confirmed by our own eyes.  The Sun is 93 Million Miles away and could hold a million earths!  It has been burning for almost 5 billion years and will be around for about another 5 billion. 

You exist because the Sun shines.

Enjoy your moment under the Sun.








Saturday, February 20, 2016

Common Questions About Analog Astronomical Photography

As a photographer who works with film, I often get inquiries on various social media as to how the images are done. This is especially true of my long exposure images. The most common questions have to do with exposure, equipment used, and how do I get those stars to be pinpoints if the exposures are an hour or more.  This blog post is my answer and I will link those that ask to it.

Astrophotography used to be the domain of amateur astronomers; astronomers did astrophotography. With the advent of the digital workflow, photographers have entered the domain, at least with what can now be done with a fixed tripod and camera arrangement. Professionals especially are well suited to produce excellent results with digital cameras. They have the resources at hand and workflow experience in post processing to best the work of what the astrophotographers of old used to struggle to accomplish with film.

Enter film based astrophotography. This is how it was done just fifteen to twenty years ago. There was really only one way to capture Milky Way vistas - with film.


The Sagittarius Milky Way Pentax 67 with 400mm SMC Takumar - Superia 100


One dispute over many professionals is experience. They are not astronomers, but many are bright enough to pick up on the basics of how the sky works. Some are truly gifted sky enthusiasts and as such produce superior work.

Personally, I do not recommend those just starting out with their interest in capturing the night sky photographically to use film. Digital is faster, easier, and encourages beginners to continue their efforts. Film based work can be unforgiving. I've tutored a few individuals who attempted it and were discouraged right from the beginning. There is so much that can go wrong.

So why film? I use film simply because it is what I have always used since I learned the craft in the early 1980's. In 2007, instead of switching to digital, I stepped up to medium format film. In 2016 I am still using film, although I have done some digital work. My other reasons for using film are aesthetics, continuity with traditions started by early astrophotographers such as E.E. Barnard, Max Wolf, and more recently, David Malin, to name but a few.

The nigh sky view from the observatory
Successive images overlapped to show fields captured with 400mm Takumar


For me this is an avocation and I can please myself with what I do, such as there still people who paint or sketch. When I perform my best work, I get great remarks but they are often mystified by my use of film despite my doing well with it. This seems to be the default nature of modern photographers. It prompts the question as to why? This also presupposes that there is no advantage to film, only disadvantages. But this simply is not true.

The Milky Way of Taurus and Perseus

Bright and dark nebulae populate this wintertime target

Pentax 67 105mm f/2.4 @ F/4 Kodak E200 - 1 Hour Exposure


Film images exist. I can show them to you. They are not virtual images or a representation of a kind. Original images exist in tangible form. They are imperfect, and they are vulnerable to the years following development.  Done properly, noise is never an issue in long exposure work with film.  Color films such as Kodak E200 deliver high fidelity red sensitive portraiture of the night skies.  Most digital cameras, DSLR's namely, need to be modified for extended red sensitivity.  Finally, rendition.  The look of film is unique.

Workflow  

The crux of this essay is to convey just how it's done. Analog astrophotography requires patience, years of practice, and perseverance before anything else. Good cameras, the proper films, and a way to share them in online communities are also required. The act of the image taking process itself is a sort of art.


The basics:


Access to dark skies away from city lights, good weather, and no Moon dictates where and when to do the exposures.

A properly aligned equatorial mount with provisions to compensate for the Earth's rotation is also a requirement. This may be the hardest part for many. I use a permanently mounted fork mounted telescope permanently aligned with the celestial pole. The celestial pole is the point in the sky where the Earth's axis point towards. Aligning the polar axis to this point allows the equatorial mount to work in parallel with the Earth's own polar axis. Alignment to within a few arc-seconds will allow extended tracking without trailing of star images during the exposure.


Heavy lifter!
Pentax 67 and 400mm SMC Takumar Riding Piggyback an 8" SC Telescope


A second part of this tracking mount is the clock drive. It's job is to rotate the polar axis counter to the Earth's rotation. It also needs to be accurate. Being a mechanical worm gear with a period of rotation of its own brings forth periodic error. No gear is perfect compared to the precision of the Earth's rotation, so we also need to correct this as time goes by. To do this we incorporate a drive corrector. The drive corrector allows the photographer to monitor a guide star as a reference to the Earth's rotation and manually correct via a small hand controller to speed up or slow down the clock drive when appropriate. This is called guiding.

The Small Sagittarius Star Cloud -Messier 24 Region
Pentax 67 400mm SMC Takumar @ f/5.6 Fuji Acros 100 1 hour Exposure


One can employ a small CCD camera in place of the guiding eyepiece to monitor the guide star and do the corrections automatically. This is called an auto-guider. It does the labor of constantly correcting the drive as needed. I do not use one, as I monitor the guide star (through the telescope the cameras are attached to) and correct manually. This is tedious work. Discouraged already?

A session goes like this:

At dusk, the camera is loaded with film (if not already) and mounting shoe to attach to the telescope is mounted to the 1/4-20 threaded tripod socket on the camera body, or telephoto lens mounting plate.

The telescope is exposed to the sky as the roof is rolled back at the observatory. Optics are checked, guiding eyepiece is installed and prepared to receive the camera.


The Piggyback mounted Pentax 67 with 165 f/2.8

The mount is made by Losmandy


The camera is mounted atop the telescope (this is called piggyback mounting) and locked into position at the proper balance point of the arrangement.

An area of the sky is selected for exposure. This involves lens selection for framing of a particular field. Lenses routinely used for this range from 105mm to 400mm focal length for the Pentax 6x7.

Once the field to photograph is established and the telescope is locked in place, a suitable guide star is centered into the double cross-hair eyepiece. This eyepiece is of the proper magnification to offer guiding corrections less than 10 arc-seconds. The star is centered at the same time the camera shutter is ready to be opened. Focus on all my Pentax 67 lenses are set at infinity stop as this seems to be true infinity. Lenses are stopped down to usually f/4.8 or f/5.6 for fully illuminated fields.

The exposure begins...................... The guide star is monitored and hand corrected for accurate guiding during the exposure. This can range from a short exposure of twenty minutes, to long exposures of an hour or more. Ninety minutes is the longest I've used in practice. One hour is typical.

In the Observatory with setup for a nights session of film based astrophotography!


Once the exposure is done, the shutter is closed and next frame advanced if another exposure is to be taken that night.

During exposure the sky needs to be scanned visually to make sure aircraft do not enter the photographic field. Gently capping the lens while the aircraft (or satellite) passes by, then removed to resume exposure. I've often capped the lens for five to seven minutes on a one hour exposure during busy aircraft times.

Wind. A windy night prevents most work from being done with longer lenses. Wider angle lenses can usually be employed with such conditions.

Dew. Nighttime moisture tends to build up on optics and this needs to be prevented or the lenses will fog up, causing stars to have halos. A small hair dryer works well. Gently “spray” the lens with the warm stream of air every 10 minutes on moist nights. Heating tapes can be purchased for such use as well. I use a hair dryer.

Developing films. Color and B&W films can be processed normally or push processed to bring out faint details. Only two currently produced films work well for astrophotography, Fuji Acros and Fuji Provia 100F. Legacy films such as Ektachrome 200, Superia 100, and Fuji 400F work great!


The Milky Way of Southern Ophiuchus
Fuji Acros 100 Produces fine astrophotographic images.
Pentax 67 400mm @ f/5.6 Fifty-Minutes Exposure


A scanning workflow is best done at home. With experience, more details and tonality can be elicited from your films. Post processing in Photoshop and astrophotographic softwares is of great benefit to film images.  Transparencies and negatives contain much more information than you might expect. Film has the added benefit of having less noise than digital captured sub-frames, so detail is high given proper exposure and proper guiding under ideal conditions.

Film based astrophotography has been a rewarding pastime. I've enjoyed the long hours under the starry dome, slowly building up photons on photographic films.  If anything, it has been a meditative process. Slowing down and doing it the old fashioned way, it is still a great way to capturing the heavens.


Flanders Pond Observatory

A shelter and a permanent setup  makes it all possible.  


More images at my Flickr site.  You can monitor my efforts, both film and digital on my Facebook page.  Twitter fans can find me on my Twitter feed.








Saturday, October 24, 2015

Obtaining Films In A "Post-Film" World

Analog photographers are passionate for their film stocks.  Emulsions are the fabric of their images, the palette conveying their work.  The technical requirements are rather important in astrophotography. Film manufacturers, although having never made an ideal film for the craft, have come close on occasion. Today there are only perhaps two films viable for astrophotography, Fuji's Acros 100 and Provia 100F.  The ideal films of yesteryear, such as Kodak's E100S and E200, or Fujifilm's Provia 400F and Superia 100 are all gone, save for the frozen stocks sitting quietly in the freezers of analog photographers.

Older stocks from the late 1990's, despite being frozen, are nevertheless decayed passed there usefulness. The latest incarnation of capable films from the 2000's will keep awhile yet.  Film degrades with time, with slower films doing well even after 10 years in the freezer.  For best storage life film must be purchased and frozen before it expires, and it must be consistently held in "suspended animation".  Therein lies the rub, finding this properly kept stock in late 2015.

Recently I have had a stroke of good luck in obtaining good film. A favorite color film of the last ten years has been Fujicolor Superia 100. I happened to come across a brick of it from an online source.  It had been frozen since new in 2008 and the price was more than fair.  Ten rolls of Superia will keep these wheels greased for some time to come.

A treasure trove!  To my good fortune, a fresh frozen brick of Fujicolor Superia 100 

The last great color film for astrophotography is Superia 100.  Not to be confused with Superia Reala 100, a great film for daylight use, Superia CN 100 defies it's specifications.  It is red sensitive, but spectral response drops off near 650nm, just shy of Hydrogen-Alpha emission line.  The manufacturers recommendation for exposures past 60 seconds is a full stop increase in exposure, not what you would expect in a good astro-film.


The beautiful region of Cygnus and Cepheus captured on  Fujicolor Superia 

Despite its apparent disagreement with its published specifications, the film performs rather well.  A 30 minute exposure at f/2.8 creates a dense negative capable of tremendous depth and fidelity.  For the best red sensitivity, Kodak's E200 has yet to be beat, however Superia's low halation allows pinpoint stars offering a more refined image.



The area of Scutum revealed by Fujicolor  Superia 100




It's time to get busy with the new stock.  I have yet to use Superia 100 on the winter sky.  I'm anticipating great results on a variety of regions of the Milky Way.  



The Messier 8 Region in Sagittarius on Fujicolor Superia 100


I believe my pursuit for film stocks is over.  Within 5 to 10 years I will complete my portfolio of astronomical images and start working on other projects.  Having photographic film originals versus digital files is a workflow choice. It is not for everyone.  May you find your methods just as rewarding.  









Saturday, February 28, 2015

Holding Pattern -Thoughts on the Coming Season



The winter of 2014-15 here in Maine has been the snowiest in a few years, akin to the 2010-11 season.  If that isn't enough to cancel imaging plans, February is going into the record books as the coldest recorded !  


Flanders Pond Observatory on The Last Day of February 
I've traded hobbies for the last month or so, swapping out the camera for a snow shovel.  Not much fun of course, but a break in the action gives one time to reflect on the upcoming season and the body of work to work on.  

The old observatory has seen better days and this spring will be a time for repairs.  The moist location has taken its toll since it's construction in 2003.  The floor and walls are needing attention, the roof however is good as the day it was built and can hold a good snow load and still slide with relative ease.

Imaging plans will include a fresh look at Sharpless 2-27 in Ophiuchus with an experimental technique for enhancing the capture of this very faint nebula. It is rarely imaged by any means and the combination of red sensitive color emulsion, proper filtering and clear dark skies will bring success.

Sharpless 2-27 in Ophiuchus

The emission nebula Sh2-27 is centered on the young zeta Ophiuchi, a runaway star.  This O type star excites the interstellar medium revealing the "bright" nebula.  The nebula itself is huge and if one could see it with the unaided eye would span 20 full Moon diameters!  Wide-field optics are necessary, even a small telescope cannot capture it in its entirety.  The image above was taken with a portrait lens looking just above the center halo of our Milky Way galaxy.

It is a challenging object to image.  It has a low declination and even natural sky brightness cloaks it from unfiltered cameras.  It usually shows up as a rather large and faint indistinctive patch of light on red sensitive film or astro modded DSLR's.  It came to my attention 10 years ago when imaging with a simple 35mm camera and 50mm lens.

Watch this blog for more information on Sharpless 2-27.  I'm hoping to best my results from 2008 and a full write up on this interesting object.










Sunday, January 11, 2015

Comet Lovejoy and a Close Planetary Conjunction

As the weekend kicked into gear Friday night, two thought were on my mind.  The first was the close conjunction of Venus and Mercury, the second was of C/2014 Q2 Lovejoy.   I dedicated Friday night to some trial images of comet Lovejoy.  The comet was speeding north into Taurus and brightening nicely.  The Moon was well past full allowing dark skies for the next two weeks.  Now was the time to strongly consider imaging our recent visitor and take in the sights as well.

Images taken Friday night with the SMC 67 200mm f/4 lens and Pentax K-5IIs were decent, but the comet remained small unless cropped heavily.  It is winter in Maine and the cold had gotten the best of me, so I planned to shoot again Saturday night with the 400 F/4 SMC Takumar.

Prior to imaging comet Lovejoy Saturday night I anticipated the close conjunction of Venus and Mercury. This night they would be at their closest, within 0.7 degrees of each other.  Because my western horizon is blocked by trees I decided to drive down to Sorrento Harbor for a clear and more scenic setting.


Looking west at Sorrento Harbor


Like a pair of jewels, Venus and Mercury adorn the western sky

Watching the tandem planets as dusk deepened was incredible.  A cosmic perspective in an otherwise ordinary earthly scene.  I would have loved to watch the planetary pair sink to the horizon, but the cold air hastened my departure.  I took in one last view before packing it in.



I took a break for dinner once arriving home.  Skies were brilliantly clear and comet Lovejoy, obvious to the unaided eye was also noticeably higher than the previous night.  I managed to get the camera and lens arrangement mounted in short order.  After a few test exposures for framing and focus, I shut off the camera and went inside to warm up and the camera to cool down.  Once I had warmed up, it was time to take some images.


C/2014 Q2 Lovejoy


I spent about an hour performing about a dozen images.  While guiding one image I saw a satellite pass my field of view in the guiding eyepiece.  After reviewing the image I was delighted to find it had  passed right straight into the comets tail and through the center of the coma!  It felt like one of those Heaven's Gate Hale-Bopp moments.  Thoughts of posting the image on crank websites filled my mind for a moment, but I know there are people that amazingly take that stuff seriously. The thought of people taking their own lives influenced by such an image sobered me.  

Ultimately, the next to last image was the keeper from the night's session.  The stars are trailed as I had guided on the coma for the six minute exposure with the 400 at f/6.7 and ISO 1600.

Lovejoy is not an extravagant comet, indeed it reminded me of periodic comet Halley in it's 1986 appearance, but it is nice to see a decent comet show up in an easy see location in the sky.  








Friday, January 2, 2015

Happy New Year



Oh to get out of bed in the morning.  It's cold outside.  It's twilight time - dawn upon the new year. Get the Keurig going and try to find some clothes in the dark without waking the spouse.   It's actually not too bad, 20's this morning and no wind.  Nice!  I can see some clouds out the living room window to the southwest drifting east, might be worth a quick trip to the pond after all.  One cup of coffee down, grab the camera bag and out the door.

A week ago the pond was completely open and not one trace of ice, the recent cold snap should have created a nice layer by now.  Flanders Pond is just north of my home and in about five minutes trekking along a camp road we arrive.   There is ice!  It's smooth too!  About an inch or so thick.  I check it with a light step.  No problem.  The sky is brightening and high clouds to the east are illuminating with golden light.  

I reach inside the bag and get the K-5 and compose about a dozen different shots as the sky changes. I'm awestruck!   Within ten minutes, the magic moment arrives.  

Yea this was definitely better than wasting the dawn on my second cup and the news on the tube.



Sunrise Upon The New Year

Happy new year.  May you all get to lose some sleep and be glad you did.

JC

Saturday, July 26, 2014

Selected Regions of The Milky Way

In my previous post I wrote of my project to photograph selected areas of the Milky Way based on the original idea that Edward Emerson Barnard proposed and implemented on the summit of Mount Wilson in 1905.

I am glad to say that the first round was successful.  I spent several hours shooting the Milky Way from my home in Maine during the dark hours of  June 21st through July 1st.  I lost much sleep and had a few difficult days at work due to the late hour required on these summer evenings / mornings. In the end it was worth it.

I performed several test frames to get perfect infinity focus then dove into the lonely hours of exposing and guiding.  Dodging mosquitoes to my person and fireflies from the exposing film, it was a feat of labor and determination.  The frames below are the fruit of those labors.

Of technical note, all exposures ran about 40-50 minutes at apertures of f/4.8 and f/5.6.  A Tiffen Haze filter was installed in the tail end filter holder on the 400mm f/4 SMC Takumar to reduce the secondary spectrum common on these conventional glass lenses.  Exposures with and without the filter was dramatic.  Star images were much tighter even though overall the filter may reduce contrast and overall sharpness.  Some reflections were noted but were rather minor.  Fuji Neopan Acros was used for image acquisition.  Chosen due to its exemplary reciprocity characteristics and fine grain.  The films were custom processed in Xtol developer by Color Services in Needham Massachusetts.

Post processing was done by converting the original negatives to digital files via an Epson V600 scanner.  Adjustments to levels and curves were completed with Adobe Photoshop.



This image portrays the individual frames below against the wider field



Messier 22 Region in Sagittarius


The Scutum Star Cloud



The Small Sagittarius Star Cloud



The Dark Nebulae in Ophiuchus


The Great Sagittarius Star Cloud

The Dark Lanes in Ophiuchus


The Southern Scutum Star Cloud

There were a few more images but I have yet to work them up for posting.  So happy to be able to share the results with you and produce at least one more time a portfolio of images captured by traditional means.  The time spent under the stars, manually correcting the guiding along the way and taking in the quiet nights allowed me to capture, albeit imperfectly, the spirit of the great E.E. Barnard.