San Pedro Valley Park Waterfall Loop

San Pedro Valley Park Waterfall Loop

Waterfall at San Pedro Valley Park

San Pedro Valley Park Waterfall Loop

A short but steep 2.2 mile loop in San Pedro Valley Park. From the parking lot go behind the toilet block and turn right to find the start of Montara Mountain Trail. After 1.2 miles winding slowly up you reach the junction with Brooks Creek Trail at a bench with views to the Pacific. Take Brooks Creek Trail down 1 mile to the parking lot, passing another bench with a view of the waterfall on the way down.

Hike starts at: 37.578046, -122.475395. View in Google Earth.

3D Printing a 72-58mm step down Camera Filter Adapter

Updated on Saturday, May 9, 2020

Thingiverse render of 72-58mm adapter

3D printed 72-58mm adapter in action on Sony RX10 IV

I have a 58mm ND5 filter that I bought to photograph the 2017 solar eclipse. It worked pretty well for that with my Sony RX100 V, but now I want to use it with an RX10 IV (which has the advantage of a 600mm equivalent zoom). The RX10 accepts 72mm filters and I want to try and photograph an ISS transit which is happening sooner than I can get hold of an adapter.

I figured someone must have done this before, but I can't find a file anywhere. It's a reasonably straightforward part - as the filter is smaller than the thread on the camera I just need a small cylinder which has a 72mm thread on the outside and 58mm on the inside. A step up adapter would be slightly more complicated to accommodate the larger filter size.

To build this I used OpenSCAD and this thread module. Open the thread module file in OpenSCAD and then you just need to subtract the inner thread from the outer thread like this:

This makes a simple 10mm tall adapter and you would just need to change the thread sizes to make it work for pretty much any combination of camera and filter (most filter sizes use a 0.75mm pitch as shown above). The vignetting is pretty extreme with the smaller filter and the size of the adapter. For this application I don't care, I'm only using the center of the image. If it's a problem for your application then it might be worth reducing the height of the adapter, at the expense of making it harder to detach from the camera.

Here is the adapter STL file on thingiverse.

After all that, I missed the transit by a couple of seconds. I thought the clock on my phone would be accurate enough but turns out it's 5 seconds off. So memo to self for next time - shoot over a longer window, or just take a video.

Philippine Tarsier

Updated on Sunday, May 3, 2020

Tarsier on Bohol

Comparing the Atmosphere to the Population of the United States

Updated on Sunday, December 15, 2019

Composition of Earth's Atmosphere

If the atmosphere was the United States here's how it would break down:

Thor, Iowa is Hydrogen. Thor is the birthplace of John K. Hanson, founder of Winnebago. 179 people.

Florence, South Dakota is Krypton. 371 people.

Butterfield, Minnesota (home of the Butterfield Steam and Gas Engine Show) is Methane, 586 people.

Lewisport, Kentucky is Helium. Abraham Lincoln was unsuccessfully tried for operating a ferry without a license here in 1827. 1,706 people.

Maquoketa, Iowa is Neon. As of the time of writing Maquoketa Caves State Park is closed for bat hibernation. 5,921 people.

Gainesville, Florida is Carbon Dioxide. It's ranked by the National Coalition for the Homeless as the 5th meanest city. 132,567 people.

ChicagoCorpus Christi and Kimball, West Virginia make up Argon. 3,042,217 people total.

All that adds up to around 1% of the atmosphere, mostly Argon.

Oxygen is about 20%, that's California, New York, Oregon, Louisiana, Lake Station, Indiana and Cedar, Kansas. 68,225,139 people.

If you're not listed then you are Nitrogen. Close to 80% at 254,334,562 people.

(Population figures from the US Census 2017 estimates. Atmosphere composition from Wikipedia. Water vapor not included.)

Book reviews for January 2019

Insurrecto by Gina Apostol

Insurrecto by Gina Apostol

3/5

 

ITHCWY Newsletter for January 2019

A Project Fi display ad on an article about Google's insane targeting prowess

The Echo Clock has one job, and it's not great at it.

I made an animation of maximum temperature anomalies by decade from the 1850s to the 2010s.

Is 2019 the year that Trump gets impeached? I wrote to my representative. Why not do the same?

Some surfing dolphins.

Farhad Manjoo calls for open borders in the New York Times for many of the same reasons I had back in 2015, before this was less unpopular ;)

Previously:

China Camp State Park

View from China Camp State Park

China Camp State Park

New Year's resolution: hike more again.

This is a combined hike of Back Ranch Meadows and Turtleback Point loop at China Camp State Park (around 2.7 miles total). Have never been to China Camp before, it's a beautiful park forty minutes north of San Francisco with plenty of interesting looking trails so will be back again soon.

(Hikes was my first blog, now folded into ITHCWY. Here's an old post about the blog. Since the last update I've ditched My Tracks because it got terrible and switched to Gaia GPS. I also moved from BlogEngine.net to my own custom blogging platform which is mostly better but hasn't worked well for my hike posts. I had to manually upload any KML files and also manually scrape out the coordinates for the start of the hike. Today I've automated this for my post by email system - I just need to attach a KML file to the email and it gets automatically uploaded to the blog and the start point is used to link to Google Maps, geocode the post and include an embedded map. Pretty cool. Hopefully this will inspire me to hike more and post more hikes as well.)

Hike starts at: 38.00733, -122.490322. View in Google Earth.

Newsletter Improvements

It turns out I'm not great at getting a monthly newsletter out. Starting with the January 2019 newsletter I've put in place a new system - I'm storing summaries of new articles when I write them and also collecting a few links that might be of interest to ITHCWY readers. These should be sent out automatically on the first of the month so I should only skip the newsletter if nothing happened. Apologies in advance if there are any teething issues with the new format.

Surfing Dolphins

Dolphins off Ocean Beach

A pair of dolphins enjoying high surf off Ocean Beach, San Francisco

Open letter to Nancy Pelosi

Sent to Speaker Pelosi today:

As an American, constituent and supporter I am writing to ask you to investigate President Trump for high crimes and misdemeanors and to pass articles of impeachment in the House.

You have said that impeachment must to be bipartisan. That would certainly need to be the end result in order for the effort to succeed. It does not make sense as a precondition for starting the process, especially if as you also said impeachment should not be started or avoided for a political reason.

You have also said that impeachment must wait for the completion of the Special Counsel investigation. Any crimes revealed by the investigation would be icing on the cake. By imposing this condition you are making the case that obstruction of justice by the President is normal, that violations of campaign finance law are minor and that using the office for personal enrichment is only to be expected. The President deserves to be tried in the Senate for these charges. The future of our democracy depends on us not accepting this behavior.

Disagreements on policy and personality should be resolved by the electorate. High crimes and misdemeanors are your job. Please do it.