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Wikipedia:Featured picture candidates/Cassiterite

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Original - Chemical formula SnO2, cassiterite is a tin oxide mineral. An important source of tin, cassiterite is commonly mined, with major deposits in Bolivia, and its presence in the Democratic Republic of Congo contributes to the conflict there. High quality crystals are considered collectible and used as gemstones. Twinning is common, usually occurring at near-60° angles. Its lustre may be adamantine to splendent, and perhaps greasy on fractures. These bipyramid samples are from Sichuan province in China and the edge length is approximately 30 mm.
Reason
it's technically good and the resolution is high.
Articles in which this image appears
cassiterite
Creator
Alchemist-hp
  • Support as nominatorMaedin\talk 07:15, 6 April 2010 (UTC)[reply]
  • Weak support -- nice picture, but there is quite a lot of noise in the darker areas. I think this problem was made worse in the uploader's second version of the picture, in which he/she attempted to brighten the picture. Might be worth using a noise reduction program or something. Also, I'd have preferred a tighter crop. NotFromUtrecht (talk) 08:07, 6 April 2010 (UTC)[reply]
  • Thanks, I'll prepare an edit tonight. Maedin\talk 08:17, 6 April 2010 (UTC)[reply]
  • Now that I'm not at work I've had a better look at the image and I'm not sure I agree regarding noise. To me, it looks like the texture of the mineral alone. I compared it to the darker original and couldn't see much difference. If it is noise, in any case, I think it's slight, and I'm reluctant to use a filter on this that might lose some of the detail. But I'll ask Alchemist-hp about a crop. Maedin\talk 17:18, 6 April 2010 (UTC)[reply]
  • @NotFromUtrecht: "there is quite a lot of noise in the darker areas" --> no, please look at the camera exif data! Show me a much better camera and I buy me it! The "surface" from the crystals are noisy. "I'd have preferred a tighter crop" --> artistically not valued and ineffective view. Please test a tighter crop for you self and you see it. Best regards, --Alchemist-hp (talk) 18:15, 6 April 2010 (UTC)[reply]
  • I'll concede that I can't be 100% sure that there actually is noise, since I know nothing about the physical properties of cassiterite. I certainly agree with Maedin that it's not worth trying to remove genuine noise if the result is that detail is lost. I tried cropping the picture in different ways, and my conclusion was that the amount of white space at the top and bottom of the picture was excessive. I'd prefer a version where the white space at the top and bottom was roughly equal to that at the side. I am happy to support this uncropped image, if there is no consensus that a closer crop would be better. NotFromUtrecht (talk) 19:46, 6 April 2010 (UTC)[reply]

Promoted File:Cassiterite.jpg Papa Lima Whiskey (talk) 15:15, 13 April 2010 (UTC)[reply]