Wikipedia:Featured picture candidates/Ferrofluid in magnetic field
Alternative images (By GMaxwell, currently unused):
- Ferrofluid would rather not form the big spikes, so if it's given enough surface area, it will spread out and make a huge mess.
- However, by carefully controlling the shape of the magnetic field (using iron rods in my case) and using a thin barrier it is possible to get the spikes and the magnet in the same picture.
- But you get much larger spikes with the magnet further away, so that the field gradient is steeper, pusing the spikes into a smaller space.
- As you move further away, it forms fewer and fewer spikes.
- Ultimately, it may just be more informative to show the fluid aligned with the north and south poles of the magnet], even though you won't get impressive spikes that way.
A superparamagnetic fluid, otherwise known as a ferrofluid, in a dish over a neodymium magnet. The image acts as a very good illustration of the peculiar way that such liquids react to magnetic fields. Original uncropped image is located at Image:Ferrofluid in magnetic field original.jpg if anyone wants to get more creative. Image created by Steve Jurvetson, uploaded by myself.
- Nominate and support. - GeeJo (t)⁄(c) • 18:04, 6 July 2006 (UTC)
Weak OpposeOppose. This is a very interesting concept, but the quality of the photo is lacking. A large portion of the fluid is featureless black (basically, the opposite of being blown out -- and conveys equally little information). The lighting for this image should have been very different, to better show the shapes that the fluid takes on. The metadata indicates the image was taken with a point&shoot. Any chance somebody with a camera that has full manual control over lighting and exposure could re-take the picture? -- moondigger 18:18, 6 July 2006 (UTC)- I have ferrofluid, rare earth magnets, and considerable camera gear. I've previously taken pictures which I think are somewhat better than this, but none that I really this do the subject justice. The stuff is *black* and if you do bathe it in too much light it will get ugly specular dots even with a large light source. Oh, and it has infinite mess making potential, it's hard to get off of anything it touches. .. Shooting it again has been on my todo list, but I want to build a jig to hold and move my magnets in fixed steps so that I can make a nice animation. --Gmaxwell 01:27, 7 July 2006 (UTC)
- You need diffuse lighting to avoid the blown highlights, preferably positioned a couple feet above the 'peaks' of the ferrofluid. Maybe a second diffuse light source behind and to the right or left, to backlight the peaks a bit, give them some dimension. I'd want to play with the lights to find what works best, which means hotlights would be preferred over flashes. Then meter from a gray card, and overexpose by 1/2 to 1 stop. Take one frame with the gray card in the shot to use for manual white balancing in post processing. Check the histogram for each exposure to make sure you're not totally blowing the highlights. It's okay if it just touches the right side, as long as it's not too much and as long as you shoot RAW. With that kind of RAW file the post-processing could bring everything in line. Another advantage of hotlights is that you could use the same setup for video. -- moondigger 05:22, 7 July 2006 (UTC)
- I'd be very interested to see the effect with top-down diffuse lighting, South-East position diffuse lighting, and a spotlight from below. —Vanderdecken∴ ∫ξφ 09:44, 9 July 2006 (UTC)
- You need diffuse lighting to avoid the blown highlights, preferably positioned a couple feet above the 'peaks' of the ferrofluid. Maybe a second diffuse light source behind and to the right or left, to backlight the peaks a bit, give them some dimension. I'd want to play with the lights to find what works best, which means hotlights would be preferred over flashes. Then meter from a gray card, and overexpose by 1/2 to 1 stop. Take one frame with the gray card in the shot to use for manual white balancing in post processing. Check the histogram for each exposure to make sure you're not totally blowing the highlights. It's okay if it just touches the right side, as long as it's not too much and as long as you shoot RAW. With that kind of RAW file the post-processing could bring everything in line. Another advantage of hotlights is that you could use the same setup for video. -- moondigger 05:22, 7 July 2006 (UTC)
- I have ferrofluid, rare earth magnets, and considerable camera gear. I've previously taken pictures which I think are somewhat better than this, but none that I really this do the subject justice. The stuff is *black* and if you do bathe it in too much light it will get ugly specular dots even with a large light source. Oh, and it has infinite mess making potential, it's hard to get off of anything it touches. .. Shooting it again has been on my todo list, but I want to build a jig to hold and move my magnets in fixed steps so that I can make a nice animation. --Gmaxwell 01:27, 7 July 2006 (UTC)
- Support - Snazzy. Iolakana|T 18:34, 6 July 2006 (UTC)
- Support. Excellent. — BRIAN0918 • 2006-07-07 04:28
- Support I've seen similar images before, and this is just as cool and HQ. Staxringold talkcontribs 05:38, 7 July 2006 (UTC)
- Support as ridiculously awesome. Alphachimp talk 07:08, 7 July 2006 (UTC)
- Support. Cool picture. Also, that may be a silly question, but can we add color to the fluid? Maybe a liquid that is lighter than the fluid and will "float" on top of it? But anyway, Support. -- Chris 73 | Talk 07:40, 7 July 2006 (UTC)
- Support, although the cropping could have been done a little better...--James 10:00, 7 July 2006 (UTC)
- That's why I provided a link to the original photograph. I cropped the image as large as I could while keeping it fairly symmetrical and without catching whitespace on the corners from the dish itself. If you can find a way to crop it better, it'd be very much appreciated. :) GeeJo (t)⁄(c) • 11:21, 7 July 2006 (UTC)
- Supportooooh wow--Childzy talk contribs 11:18, 7 July 2006 (UTC)
- Support. Interesting! Cab02 15:41, 7 July 2006 (UTC)
- Oppose, while the concept of a ferrofluid seems interesting, this picture doesn't convey it to the full extent. The caption states there is a magnet hidden somewhere. A setup where the magnet is above a pool of FF with some FF on the magnet would be much more illustrative. You'd have the skikey pattern on the FF on the magnet, and at the same time the attraction of the FF below would be visible. Furthermore the dirty plate background is just plain unappealing. Reshoot! --Dschwen 16:19, 9 July 2006 (UTC)
- So I've got better pictures, there are actually about 200 in my collection. But I'm not sure if I'm going to release them under a free license and upload them, because I'm getting pretty tired of MediaWiki thumbnailing
making my images look like crap... especially on the image pages. I've thrown up some small sized examples on the right, Cheers. --Gmaxwell 06:47, 10 July 2006 (UTC)
- Oppose I have seen better photos of ferrofluids. This is rather ugly... --Janke | Talk 17:16, 9 July 2006 (UTC)
- Support I actually think having a magnet visible would distract from the cool part. --Mr. Lefty Talk to me! 00:47, 10 July 2006 (UTC)
- Support -- Samir धर्म 01:47, 10 July 2006 (UTC)
- Weak Oppose Even though the picture is ugly, it shows the intresting property of ferro fluids. The image would appear better if the container is a clean one and if the peaks stand out clearly.
- Note that it's pretty difficult to get a clean container with these fluids, as the effect demonstrated tends to push some of the liquid across the surface, resulting in the brown streaks you can see on this photograph. GeeJo (t)⁄(c) • 14:28, 10 July 2006 (UTC)
- Not difficult, just takes time... I used a cotton swab with solvent on it to clean up the glass after moving it around in my pictures linked above. Although if you drip it straight on there is no initial mess and it's fun to watch the fluid jump out of the pipet. :) --Gmaxwell 15:04, 10 July 2006 (UTC)
- Note that it's pretty difficult to get a clean container with these fluids, as the effect demonstrated tends to push some of the liquid across the surface, resulting in the brown streaks you can see on this photograph. GeeJo (t)⁄(c) • 14:28, 10 July 2006 (UTC)
- Support Most interesting phenomenon. If you don't get it in this time, try renominating under the heading 'blueberry pie'. --Philopedia 16:11, 10 July 2006 (UTC)
- Oppose. The background is distracting. Gmaxwell's photos show the spikes better. --Pharaoh Hound 11:33, 11 July 2006 (UTC)
- Support needs to be a bigger pic on Ferrofluid Joe I 19:45, 11 July 2006 (UTC)
- Oppose per the dirty plate. Would support the last alternative image, though, as the background isn't blank but isn't dirty either, and the ferrofluid aligning at the poles is perfectly illustrative.
- Me. Damn. Suntiger 20:28, 12 July 2006 (UTC)
- Oppose Poor quality image, and I doubt it will be used in the article after someone gets around to putting the replacements I made in... --Gmaxwell 01:14, 13 July 2006 (UTC)
- Oppose So close, but it has some quality problems. -Ravedave 03:35, 13 July 2006 (UTC)
- Weak Support I really like the image and think that for images of this kind the technical quality is less important that it may otherwise be. However, the reason I am only showing weak support is because the darkness of the image and the perspective used does not portray the ferrofluid as clearly as it could be. --Newton2 22:13, 13 July 2006 (UTC)
- We now have a number of new images, see Talk:Ferrofluid. I hope you find those more informative. --Gmaxwell 23:28, 13 July 2006 (UTC)
Not promoted Although this was very close. Even counting the nominator there were 14 supporters and 8 opposers, which just isn't enough of a majority to call it consensus. The existance of Gmaxwell's images is another factor. Once they've been added to the article I'll nominate them myself if noone gets there first. Raven4x4x 06:32, 14 July 2006 (UTC)