Donate now to keep mindat.org alive!Help mindat.org|Log In|Register|
Home PageMindat NewsThe Mindat ManualHistory of MindatCopyright StatusManagement TeamContact UsAdvertise on Mindat
Donate to MindatSponsor a PageSponsored PagesTop Available PagesMindat AdvertisersAdvertise on Mindat
The most common minerals on earthMineral PhotographyThe Elements and their Minerals
Minerals by PropertiesMinerals by ChemistryAdvanced Locality SearchRandom MineralSearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
Keyword(s):
 
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
StatisticsThe ElementsMember ListBooks & MagazinesMineral MuseumsMineral Shows & EventsThe Mindat DirectoryDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day Gallery

Using a Ring Light for Dark Field Illumination in Mineral Photography

Last Updated: 14th May 2015

By Volker Betz

By Volker Betz

Ring lights are common devices for close up photography. They a typical mounted around the lens and light direct in direction of the object. This is fine in many cases, but fails mostly with mineral specimens.

Dark field illumination is a lightning method common in microscopy. The light is directed in a almost 90 ° angel to the view of the camera. It is a superb method to photograph coins, as it enhances contrast on flat lustrous objects and is also useful for macro photography of minerals.

Experiments showed that gives good results in many cases. The method can also be transferred to the close up range and larger objects if a ring light of sufficient diameter is used. As a rule of thumb, the diameter must be about twice the largest dimension of the specimen.

A ring light is easy to make by just glueing self adhesive LED stripes ( cold white ~ 6000 K) into a cylindrical plastic container. The cover of the container is not used and the bottom cut off. It can be hight adjusted by means of a small stand from aluminum profile (see picture) and some screws.

Home made LED ring light for darkfield illumination. Diameter 16 cm with 100 LED


Photography is done typical in a vertical setup, with the the specimen mounted a few cm above a glass plate with black background, or a sheet of acryl glass for light background.

The method gives good results also with samples which have very litte contrast, like the shown natrolite specimen.
Natrolite specimen from Ölberg near Hundsangen, Westerwald, Germany. Size 8 cm.






Article has been viewed at least 5743 times.

Comments

Very impressive. Thanks Volker!

Jolyon & Katya Ralph
16th May 2015 4:34pm
Very nice! Thanks

Luís Costa
25th Jun 2015 11:23am

In order to leave comments to this article, you must be registered
Mineral and/or Locality  
Mindat.org is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2017, except where stated. Mindat.org relies on the contributions of thousands of members and supporters.
Privacy Policy - Terms & Conditions - Contact Us Current server date and time: November 23, 2017 18:36:51
Go to top of page