Monday, March 2, 2015

Nimrud Lens

After keeping skyasanisi for several years, I am switching to a new format to document and share all my work in art, engineering, photography, and films.


Thursday, June 19, 2014


I went to my first conference this May in Miami (OSA BioMed), and got to give a talk there.  For the trip, I brought my old Nikon FM.  It was probably a year since I shot with it last, because I have had a lot of trouble getting focused images.  Perhaps its the big clunk from the mechanical shutter that makes it difficult to keep the camera steady.  Who knows... I was actually really happy with this roll though, and I think I may bring it back.

A couple views from our amazing apartment that Karla found.  The mural is from Wynwood, which is a neat neighborhood filled with impressive graffiti.

miami1 miami4

I just can't resist the double exposure feature on the Nikon FM.  I know I overuse it, but you're almost guaranteed an interesting shot...

Sunday, May 18, 2014

Tokyo Balloon Project Update

After drilling many holes, I opted to paint the pegboard.  I wish I could have just stained it.  However, due to learning curve of drilling many holes into plywood, there were quite a few bad spots that I filled with putty.

Originally, I painted the board as shown.  Immediately upon painting the last colored rectangle, I decided that I hated what I had done.  I don't think I have a good sense of color.  I re-primed the board, and painted contour lines of the original image.  Matlab helped me figure out which holes corresponded to which pixels in the image.  Much better I think!

tokyoPaint1 tokyoPaint4 tokyoPaint2 tokyoPaint3

Saturday, March 29, 2014

Macroscope Vs. iPhone 4s Microscope

In my lab, I'm working on constructing a two photon microscope.  Two photon microscopes are popular in neuroscience research and enable functional imaging of individual neurons in living organisms, as well as structural imaging of blood vessels, neurons, and glial cells.  Google "two photon microscope neuroscience" to see some amazing images!

Before joining my lab and starting this project, I thought of light microscopes (the ones you use in high school) as the primary devices used for magnifying objects.  However, you can get some pretty sweet images of magnified objects using a DSLR or iPhone.  By flipping a prime lens in front of a telephoto lens, you can magnify objects on your DSLR (it's sorta a poor man's macro lens).  They are generally called "macroscopes."

I flipped my 50mm Nikkor lens and mounted it with an adapter to my 210 mm telephoto lens.  I could magnify objects to around 4.2 times!  Check out this quarter.
macroScope1 coin

Another neat trick is to place a lens in front of your iPhone camera (focal length around 35mm).  I took the lens out of a disposable camera (focal length around 30mm) and taped it to my iPhone, then zoomed as much as I could on the iPhone.  Check out this circuit from the disposable camera.  I think the idea is very much the same as the macroscope.
iphoneScope circuitI

It was neat to compare the images from these two "microscopes." Here's an onion and a leaf.  DSLR macroscope on the left, and iPhone microscope on the right.
leafM leafI onionM onion!
The depth of field on both of these is terribly small so it's difficult to get an entire image in focus. The images are definitely comparable. The iPhone is much easier to use, and weights a ton less then the bulky macroscope set-up.

Links: People have already done all this stuff, but it was neat to do myself!
iPhone Scope

Technical details (if you want to know):
The magnification is the height of the image divided by the height of the object. To calculate this, I placed a ruler in front of the lens to measure the field of view (the object).  Then I divided the size of the CCD or CMOS sensor by the field of view (the image).  For example, the field of view in the x direction for the macroscope was around 5.5mm and the CMOS sensor has a width of 23.6mm.  Therefore, the magnification was 23.6/5.5 = 4.29.  This actually agrees well with theory: the ratio of the focal lengths of a macroscope is equal to its magnification -> 210mm/50mm = 4.2!
Technically, I guess the magnification was less on the iPhone: 3.42mm/3.5mm = 0.97.  This was because the CCD on the iPhone is so much smaller than the DSLR.
DSC_0077 rulerI

Pen from the macroscope:

Wednesday, February 26, 2014

4240 Holes

I have finally completed drilling 4240 holes for my Tokyo balloon project!  It was physically exhausting, sometimes even maddening.  Glad that this part of the project is finally completed!  So many holes...

wood1 wood2

More holes...

Drilling so many holes straight and at the same depth was made possible by this little device:

Wednesday, February 19, 2014

Grandfather's Model Airplane Log

My Grandfather has inspired me a lot throughout my life. He started working as an aeronautical engineer for Piasecki Helicopter Corporation and later Boeing (once Piasecki was acquired by Boeing).  A lot of his work involved troubleshooting new aircraft with pilots.  He got to work between other engineers and the pilots who were actually operating the aircraft, even traveled to other parts of the world.  It sounded like an awesome job.

The last time I visited my grandfather, he showed me a model airplane log that he kept between 1937 and 1943 (from age 12 to 16).  It is an incredibly well organized document: detailed accounts of lessons learnt from failed models, technical specifications for each model, time of flight, what happen to the craft after flight.  Knowing the type of person my grandfather is, it isn't surprising that he was the precocious youngster who wrote it.  From the log, you could pick up on qualities and quirks that my grandfather still has today.  It's amazing he did this without Word... he used a type writer and left spaces to glue in pictures of his models.

Yet, he was still a kid.  He sometimes set his models on fire to watch them "burst into a flame and fall out of the sky", and got yelled at by grumpy neighbors for planes crashing in their yards.

The log was in bad physical condition, so I scanned in all the pages describing the 26 airplane models that he constructed.  Here are a few pages:





Thursday, January 30, 2014

Longwood Gardens

Also on my trip back east, my ma and I went to Longwood Gardens.  The garden was covered in lights, and really a sight to see if you're around PA in the winter time.  I paid much greater attention to the history on this trip, and read about the amazing Pierre du Pont who bought the property before it was sold for lumber.

longwood tree ma