Vintage Glass

One of the advantages of a mirrorless camera, like the EOS-M, is the very shallow backfocus requirement. The distance from the lens mount to the sensor is quite small, allowing use of just about any series of lenses on the market. All that is needed is the correct adapter, a need that several specialty manufacturers have addressed with products. The result is that the camera is useful in a wide range of photographic experiments and projects.

EOS-M with Canon 24mm f/2.8 FD
The EOS-M with a Canon 24mm f/2.8 FD lens mounted
This includes older lenses from years past such as the Canon manual focus FD system from decades ago. Forgotten by most, these lenses have none of the modern features photographers have come to expect. No autofocus, no image stabilization, just solid optics from an age now past. These old lenses are not obsolete, there are creative uses still available for these classic lenses.

Any sort of zoom lens need not apply, the quality of the older zoom lenses often suffered. Designed without the aid of modern optical design software and without aspheric elements these designs fall short of modern standards.

You can find these classic lenses languishing on shelves in the back of camera stores, in garage sales and on eBay. There is a lot of junk out there, it takes some research to differentiate the good from the bad. A couple quick rules of thumb will sort out most of the junk… Stick to a first rank name in old camera gear; Canon, Nikon, Ziess, Hasselblad, and Leica. The next hint of a hidden gem is the focal ratio. The classic primes were fast, f/2.8 or faster. Still, it is wise to look up the history of the lens before plunking down any cash. The good lenses will be well written about, even in modern times. You will find good references with a quick web search.

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Venus at Maximum Elongation

Today Venus is at maximum elongation, as high in the dawn sky as it will get for this morning apparition, about 46°. After today the planet will begin its long slide back into the glare of dawn. It will disappear from view around the beginning of May, 2016 and reach superior conjunction on June 6th, 2016.

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Kamaʻāina Observatory Experience

One of the things the recent controversy has starkly revealed is the lack of understanding of what we do on the mountain. Myths and misunderstandings pepper the comment sections of local newspapers and echo on Facebook.

Keck Domes
Looking at the Keck domes from the Subaru catwalk
In an effort to change this the obsevatories are introducing a new tour opportunity. The Kamaʻāina Observatory Experience is a free tour of an observatory, with free transportation to the summit for local residents. All that is necessary is a local ID to get a chance to see inside one of the summit facilities.

Rumor has it that Hawaii Forest and Trail will be providing the transport, a comfortable service with knowledgable guides.

Surprisingly this was announced by President Obama at the White House Star Party this week. A rather high profile announcement for a local effort.

I will probably volunteer to help out and be a tour guide when it comes Keck’s turn to host the tour.

Information can be found on the website http://www.kamaainaobservatoryexperience.org

White Mountian

A great deal of mythology swirls about our mountain. Some of it may be true, much is probably not as wishful thinking and reality collide on the summit. The current debates have moved every little detail into the light.

Mauna Kea White
Mauna Kea with a fresh covering of snow and ice
One of the claims I have heard repeated a few times recently is that in the past Mauna Kea always had snow, even in summer, making the name “White Mountain” very applicable.

I had my doubts about this. Whenever these questions arise it is important to check the records. Fortunately this has already been completed for us… Norbert Schorghofer, Elianna Kantar, and M. Puakea Nogelmeier at the University of Hawaii combed through the historical records looking for observations of the presence of snow atop Mauna Kea. What they found is that there were any number of records indicating the lack of snow on the mountain.

Follow the link and read the paper, it is a fascinating view into the past of Mauna Kea. Included are excerpts from ships logs and diaries of early visitors to the islands. At the end is a convenient timeline of the accounts covering the first century of written records and a set of three conclusions drawn from this information. The author’s conclusion is clear, Mauna Kea has not featured permanent snow cover any time in the last few centuries.

There was a time when the mountain featured permanent snow and ice fields. During the last ice age, around 12,000-11,000 years ago, there was permanent ice and active glaciers in the summit region. Along the access road there are textbook glacial features to be seen, glacial polish and moraines. This was gone before humans arrived in the islands. What we see today was probably much as it was over the past few centuries, as borne out in the records of the first European voyagers to make it to the islands. Snow may have been more common, but there were certainly periods when no snow was to be seen atop the summit of Mauna Kea.

These historical accounts date from long before human activities had begun dumping vast quantities of carbon dioxide into the atmosphere. We do face an uncertain climate future, warming temperatures may reduce snowfall. The opposite may also be possible, warmer sea surface temperatures may create more precipitation at the summit with heavier snowfall events possible.