Science-Related Photos: Post & Share Yours!

[turbo]

Nice shots, Andy. I missed the refractive effects from November, and those are quite interesting.

 

[Borek]

Critical angle in a cheap plastic prism.

Walls are not perfectly flat (you know, cheap plastic) so I had to Photoshop it a little bit

 

[Andy Resnick]

Borek- very nice!
You just (re)invented the Abbe refractometer... :)

 

[Andy Resnick]

It's funny how things work- months go by with nothing good to photograph, and then a week of 'hits'.

I found, for lack of a better word, a 'thing'. It's a piece of a diffractive optic- the kind that makes different images as you tilt it. Not a hologram!

Here's the front taken at two different angles with respect to the lens:

[PLAIN]http://img809.imageshack.us/img809/949/dsc4563.jpg

[PLAIN]http://img844.imageshack.us/img844/5606/dsc4562e.jpg

You may have seen these things- in this case, there are balloons that move across the field as the tilt angle is changed.

I wanted to see how they work, so I put it under the microscope and tried a few different illumination methods- crossed polars worked perfectly. Here's some magnified shots of the base of the balloons:

[PLAIN]http://img846.imageshack.us/img846/6433/dsc4566.jpg

[PLAIN]http://img852.imageshack.us/img852/756/dsc4567.jpg

[PLAIN]http://img856.imageshack.us/img856/6614/dsc4569.jpg

Pretty!

 

[Andy Resnick]

I'll have a few interesting photos shortly- here's a random one in the meantime:

[PLAIN]http://img546.imageshack.us/img546/9513/newout99999dostack101.jpg

Andre clued me in about 'focus stacking'- I am used to taking image stacks and then deconvolving them as part of my research, and focus stacking is a simplified version. For focus stacking, I use Combine ZP (a free program):

http://en.wikipedia.org/wiki/CombineZP

It works well, but it takes some time to understand the appropriate 'parameter space'.

The image above was taken using the 16mm luminar at a magnification of about 30X. I took about 20 images, each time advancing the sample slightly forward- each individual image has only a thin sliver of in-focus components- and then told CombineZP to put them all together.

The image is of a gold nugget (although at 30X, it's not much of a nugget). Sometime last century we took a family trip to South Africa (this was during apartheid) and we took a tour of a working gold mine. At the end of the tour, we each got to pick a rock of ore and take it home. At that time, the mine processed 2 tons of ore for each ounce of gold, and used an amazingly toxic sludge to extract the gold (I remember cyanide was involved).

That's it for now- I have another image stack cooking in the computer, and should post the results shortly. If you want to see someone who *really* does amazing things with focus stacking (among other things...), check this guy out:

http://www.flickr.com/photos/johnhallmen/

 

[Andy Resnick]

Just to close out Post #54- here's an edge-on shot of the optic:

[PLAIN]http://img862.imageshack.us/img862/8673/dsc4661.jpg

Starting at the bottom is the magnetic base, the bright layer is (I think) simply a highly (diffuse) reflective layer on which the ink is printed (the colored dots). Finally, on top, are the molded plastic cylindrical lenses. Maybe I'll try cutting off the plastic to see what the printed pattern looks like.

 

[kland1]

Come on, I know I'm not the only person with scientific photos lying around. I know there are other scientists around here.*looks under some rocks (but only finds some earthworms)*

Post post post!

Hello I have spent the last few years working on a Tesla Turbine and even though I'm not in a science lab I am wearing a lab coat so that should count right?

So here is a photo pallet of science pictures on the turbine work, http://www.seabirdadventure.com/photos/the-tesla-turbine

I will attempt to attach a couple of lower res pics in this post.

Kris

 

[Andy Resnick]

I like the image of a flame (is that right?)- how did you take it?

 

[kland1]

I like the image of a flame (is that right?)- how did you take it?

Hello Andy, thank you.

Actually I'm not sure where I dug that picture up, It was sometime last year when I was working on the Tesla Turbine, I'll include a pic of it running here in this post. Also If you would like to read about the testing , http://www.seabirdadventure.com/tesla-turbine/tesla-turbines-are-very-different , that went into it for the last four years or so.

However the picture is the Turbine running on 90% H2O2 instead of flame so the picture is not from this test for sure.

Let me know if you'd like to see any more pics.

Cheers, Kris

 

[Andy Resnick]

I put a small piece of those cheap transmission gratings (we have
them lying around for K-12 outreach):

https://www.amazon.com/dp/B001DSGYEO/?tag=pfamazon01-20

in the filter holder of the 15mm and got this:

http://img560.imageshack.us/img560/9092/dsc6569c.jpg

I like the effect; I'll have to play around with this some more...

 

[Andy Resnick]

Moving the diffraction grating to the backside of the lens adapter, I was able to make the spectra appear closer to the source. It seems possible to use the camera as an imaging spectrometer for various sources- here's the sun:

[PLAIN]http://img828.imageshack.us/img828/6797/dsc6607.jpg

and streetlights:

[PLAIN]http://img202.imageshack.us/img202/5695/dsc6629r.jpg

Both of these were taken with the 15mm, and the solar image also contains the secondary spectrum. As expected, the sun provides a continuum while the Hg streetlamps have discrete spectra.

Using the 400mm, I was able to capture the spectrum of Polaris:

[PLAIN]http://img811.imageshack.us/img811/2498/dsc6632d.jpg

IIRC, this was a 1s exposure. On the original, faint spectra from other stars can be seen, but I need to work a little bit to improve things.

It's not clear if I can extract quantitative spectral information from these, but it would be interesting if I could see differences in stars, or measure atmospheric attenuation.

 

[viko]

spherical wave diffraction
:D

 

[Andy Resnick]

I wrote a bit about this in <shameless self promotion> my blog </shameless self-promotion>- by putting a diffraction grating in the light path, you can convert your camera into an imaging spectrometer. Here's a collection I finished up last night:

[PLAIN]http://img842.imageshack.us/img842/2492/spectra6.jpg

The image was downsized to comply with PF guidelines; a larger version with the measured spectra is posted on my blog. Going from top to bottom:

Sun (primary and secondary rainbow)
Incandescent lightbulb
Compact fluorescent lightbulb
Saturn
Porrima

Porrima is the star closest to Saturn right now. My 'spectrometer' has a resolution of about 0.3 nm/pixel, not enough to see a lot of detail, but enough to tell the difference between Saturn and Porrima, and (possibly) the difference between sunlight and the reflected light off of Saturn.

I'm excited about this- and looking forward to capturing Mars when it is in a more favorable position.

 

[Andy Resnick]

Here's some pics of a couple interesting items unearthed from the machine shop. The first one is a 'variac' (a variable AC transformer) that was still in the original 1963 package with a copy of the purchase order. The first image is the whole device with the top cover removed, and the second is a close-up of the windings.

[PLAIN]http://img820.imageshack.us/img820/7466/dsc7664g.jpg

[PLAIN]http://img143.imageshack.us/img143/1796/dsc7671b.jpg

I don't know what this next object is, so I'm calling it "the metatron". It's also never been used, but it didn't have any paperwork nearby. It's very intricate, and I could spend another day setting up other shots.

[PLAIN]http://img121.imageshack.us/img121/2548/dsc7540m.jpg

[PLAIN]http://img31.imageshack.us/img31/8102/dsc7546h.jpg

[PLAIN]http://img823.imageshack.us/img823/2586/dsc7544z.jpg

[PLAIN]http://img846.imageshack.us/img846/722/dsc7545.jpg