SUPPORT US. If mindat.org is important to you, click here to donate to our Fall 2019 fundraiser!
Log InRegister
Home PageAbout MindatThe Mindat ManualHistory of MindatCopyright StatusWho We AreContact UsAdvertise on Mindat
Donate to MindatCorporate SponsorshipSponsor a PageSponsored PagesMindat AdvertisersAdvertise on Mindat
Learning CenterWhat is a mineral?The most common minerals on earthInformation for EducatorsMindat ArticlesThe ElementsBooks & Magazines
Minerals by PropertiesMinerals by ChemistryAdvanced Locality SearchRandom MineralRandom LocalitySearch 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
Mining CompaniesStatisticsUsersMineral MuseumsMineral Shows & EventsThe Mindat DirectoryDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day GalleryMineral Photography

Mineral PhotographyExposure problems caused my fluorescence?

30th Jul 2017 15:59 BSTLarry Eicher

04237170015651845423528.jpg
Sirs:


Occasionally I come across samples which present exposure nightmares. I am currently working on gypsum which is posing this problem

There are, perhaps two crystals in the upper right which are causing the problem. I exposed this one at ec -3. I used one Neewer led light on low setting. The light had a diffuser mounted. The light also had to go through a white plastic tubular diffuser/reflector. I held almost all detail in the "two" crystals. I pushed up "fill" light and "brightness" to help compensate for the under exposure. Could this "hot" spot be caused by UV light? I don't see how since I can't see UV light, but I am at a loss.


Regards,

Larry

30th Jul 2017 21:21 BSTDoug Daniels

I doubt it has any UV problems. It is likely the orientation of those two crystals with respect to your light source. Notice how the crystals along the lower part are much brighter than the main part of the specimen?

7th Nov 2017 18:09 GMTLarry Eicher

Doug,


Thanks for your reply and apologies for my tardy reply. I have since come to the same conclusion. I was just beginning to consider UV light at the time I asked. I have learned enough to know that I needn't worry about UV light until my camera is modified so as to capture light in that range.


I have since modified my setup adding the option to rotate the subject until the faces are aligned such that we get no blown out highlights. I don't yet have an image of the "new" setup but if you are interested, I will create one and post it.


Regards,

Larry
 
Mineral and/or Locality  
Mindat.org is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization. Public Relations by Blytheweigh.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2019, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters.
Privacy Policy - Terms & Conditions - Contact Us Current server date and time: August 25, 2019 05:41:15
Go to top of page