Wikipedia:Picture peer review/Vibrating Glass Beam

 
The vibration of a beam, such as this cantilever made of borosilicate glass, can be described with the Euler-Bernoulli beam equation alongside a loading function which includes inertia, gravity, and possibly drag, and functions describing the variable section modulus and linear density. The traces of the exposure show decaying oscillations and motion that is not simple harmonic.

Flash photo freezes in time the extent of vibrations of a cantilever beam, exposure beyond flash reveals the whole path of the beam and creates an interesting effect with the lighting.

Comments:

  • Wow! This is a great example of using a photograph to illustrate a mathematic and engineering idea. I have a question about the current caption on Euler-Bernoulli beam equation; don't you have to model that vibration using a point mass on the end, as your glass beam has an enormous glob of glass on the end? Didn't you take a picture of the glass with a glob because it vibrates so much prettier? On the technical specifications of the image, though; the background kills it for me. The white (and yellow) background on the left is very distracting, and the gray bits on the bottom aren't wonderful, either. If you did another version of this image with a more uniform or at least more aesthetically pleasing background, I'd vote for it. You are taking an image of glass with a flash, so I'm okay with the blown highlights, but I don't know how other voters would feel about it. Enuja (talk) 00:17, 13 September 2007 (UTC)[reply]
    • Thank you! Could be modeled with a point mass, but you need a variable linear density function anyway so it would just be another thing to worry about. For some reason this reminded me to mention section modulus. -Ben pcc 01:18, 13 September 2007 (UTC)[reply]
    • Suggested fixes in place.
While the background is certainly less distracting, I don't see as much of the non-flash vibration in this particular image (except for two very bright spots). Maybe the distracting background is necessary to have enough diffuse light to show the whole of the vibrating glass beam, I really don't know. I feel terrible about not personally liking this version, either, because they ARE both very good and very illustrative, and you did follow my suggestions! But I think you need both a less distracting background (doesn't have to be solid black) and to be able to see the range of beam positions along the length of the beam for this to be a featured picture. Enuja (talk) 01:28, 14 September 2007 (UTC)[reply]
I honestly don't think I can do both. The reason why the previous image showed more traces is that the room was well lit, in addition to a flashlight. This version is in a dark basement with only the flashlight. I personally like this one better for the article so I won't revert, but I'd be lying if I didn't mention that the problem you mention didn't worry me as well.-Ben pcc 01:40, 14 September 2007 (UTC)[reply]
I remember a particularly striking background on an FP, so I looked it up; this FP was done with a black piece of paper as a vertical background and the insect on white piece of paper. I think you might be able to get the reflections and a clean background by doing this in front of a black piece of paper, with plenty of background illumination. Enuja (talk) 01:58, 14 September 2007 (UTC)[reply]
I experimented with many black backgrounds for the first one, including paper which didn't work at all. The best I could find was my black sweater (this ofcourse doesn't justify the bright crap on the left. Can't remember why that's there), its fuzziness lends to the "gray bits" you observed. -Ben pcc 02:19, 14 September 2007 (UTC)[reply]
I just finished 3 hours and 62 exposures of experimenting and I conclude that what's uploaded now is the best. I was able after more experimenting to get a black background in a well lit room and almost replicated the original image's appeal with a (near) black background. However I like this one better- I think it has more stuff in terms of science. I'm gonna give it a try in FPC though there's no seconder (a look at the archive shows that there almost never is?). I know you (Enuja) are not quite satisfied, but thanks for the suggestions, I would've stuck to the original image otherwise. Fir's background looks unreal, by the way, that was so clever. — Ben pcc 22:25, 15 September 2007 (UTC)[reply]

Seconder:

Image nominated on Wikipedia:Featured picture candidates as Vibrating Glass Beam by Ben pcc on 15 September 2007. --jjron 03:52, 20 September 2007 (UTC)[reply]