For Zeolite

[LD]

I know you''re interested in CC Garnets and I wanted to show you this one. It''s over 4.67ct and is a tawny brown in daylight (I can''t capture the colour accurately but it''s more tawny than the photo suggests) and changes to red wine in incandescent light! I adore the incandescent colour as it''s rich and vibrant.

Apologies for the photos because they''re not good but I have a terrible time photographing colour change gemstones!

 

[LD]

Incandescent:

 

[zeolite]

That is a good change, and the incandescent color is rich. I have a number of c/c garnets whose change is not that good.

A general comment about c/c garnets: They tend to have an intense incandescent color, and a more washed out, pastel daylight color (my garnets included).

I am most attracted to c/c gems that have about an equal intensity (but different color) in both lights. My sapphire, spinel, and diaspore, as well as alexandrite (which I don''t have) seem to be more balanced in this respect. I can''t seem to think of a single c/c gem that is more intense in its daylight color.

 

[LD]

My passion is also cc gemstones. I find them fascinating! If you want to add an Alexandrite (a good one) to your collection, you should contact David Weinberg at multicolour.com. He is an authority and can help you find what you''re looking for. The Indian Alexandrites tend to have the most beautiful daytime colour and can have the same intensity colour change.

I''m interested that you mentioned Diaspore. Although I like them I tend to find that the daytime and incandescent colours are paler than I''m drawn to - although it''s a lovely sparkly gemstone

I was lucky to buy a cc sapphire bracelet sometime ago with about 15 separate .5ct gemstones and while I love to guess the colour each stone will go, I agree that it looks far more impressive in incandescent lighting than natural light!

If you discover the secret of accurately photographing cc gemstones I''d love to hear it because I have to take about 1000 photos until I get one that''s near to what I''m seeing!!!

 

[zeolite]

If you discover the secret of accurately photographing cc gemstones I''d love to hear it because I have to take about 1000 photos until I get one that''s near to what I''m seeing!!!

What does this mean? Are you having trouble getting the color correct, or the tone, or the saturation, or some other problem, such as exposure or sharpness, or depth of field? Perhaps I can help, if I know what you are having trouble with.

 

[LD]

As an example, I can''t photograph the green of my Alexandrites in natural daylight. I "see" the green through the lens but the minute I take a photo (with flash, without flash, changing the white balance etc) I get the incandescent colour. Even on absolutely terrible Alexandrites with very poor colour change this happens and in fact, enhances the incandescent colour! However, the incandescent colour photographs beautifully under electric light and is pretty accurate for the good colour changers. What am I doing wrong?????!!!!! Your advice would be appreciated.

 

[zeolite]

Some questions: I assume that you use a digital point and shoot camera? (one where you can''t change lenses?). You don''t have a tripod? What software do you use to process your digital pictures?

This looks good. How did you do this?

 

[LD]

That was a complete fluke! I''ve tried to use the same settings at other times but no luck!!!

Yes to a digital camera without lens change capability. Yes to tripod. Only download images onto my computer but don''t adjust colours or anything once downloaded. Try to capture the colour by changing camera settings (i.e. speed, white balance, lighting etc etc). Does that help?

 

[zeolite]

Yes, that helps in understanding your situation. It appears that the only color control you have with your present system is changing white balance and/or changing lighting. Neither approach gives very good control of color.

Let me mention two solutions: the expensive one and the PS policies impossible one.

You could go to Adobe.com and buy Photoshop elements for $180. Or you could buy a Canon used digital SLR (DSLR) camera (one with interchangeable lenses), and get the Photosop Elements that is included with this camera. The used camera could cost $300-$400; the same camera sold new 4 years ago for $1500.

By buying a Canon DSLR camera and shooting in raw (not jpeg), I have almost infinite control of white balance, after the picture is shot, with extremely fine control and adjustment of color.

Now, the PS policies impossible one: I''m trying to be very careful in not violating any policies, but there should be some system of private messages here, and that does not seem to exist. You could shoot your picture, and send or email it to me. I could color correct it in my full version of Photoshop and return it. No cost at all to you. It would demonstrate what Photoshop Elements can do.

 

[Richard M.]

Date: 9/9/2008 6:39:23 PM
Author: zeolite
there should be some system of private messages here, and that does not seem to exist.

That certainly can present difficulties at times, can''t it? For instance I''d like to ask off-Forum questions about your F15T8 Excella fluorescent bulbs/tubes, i.e., where do you get them and what kind of fixtures do they require? I went to your Atlanta lighting link but they seem to sell them only in cases of 30 plus shipping -- that''s a bit of overkill for me.

Richard M.

 

[zeolite]

Since you have a website, I could contact you privately there. But I and other people here on PS don''t have a website.

F15T8/Excella: I bought mine at a Tucson gem show for $20 each. This company is cheaper, and appears to sell in small quantities:

http://www.sunlanlighting.com/sunlanlighting/Page4.html

This link above describes an F15T8 lamp as a nominal 18" bulb (mine actually measures 17.25"). With that information, I serached for a cheap fixture that will take F15T8 lamps:

http://www.amazon.com/dp/B000ZN0LZG?smid=A1IZCISXTFZ9OX&tag=nextag-tools-tier4-20&linkCode=asn

Note that they include a F15T8 lamp, but I''m sure it isn''t Excella phosphors. Just this minute my fixtures arrived. I haven''t even opened the box.

 

[Richard M.]

Thanks zeolite. I''ll wait for your experiments before ordering but this looks like a reasonable solution for the time being.

Richard M.

 

[Fly Girl]

This is a very interesting thread. I have an artist daughter, and lighting in our home is important to her painting, as well as to us for making our photos and gemstones look nice.

Our family recently stayed in a hotel with compact fluorescent bulbs in the room, and not only did our clothes and magazine photos look terrible, my ruby looked totally dead and grey. My husband and I decided right then that we would never have that awful lighting in our home.

My sister and her husband recently purchased a sofa. They thought it was brown, which was how it looked in the store. But, in their home, it was green.

I was working on a jigsaw puzzle last winter, and I couldn''t tell the colors apart except when it was sunny out. I can''t sort some of my husband''s dark socks except in full daylight.

I appreciate the lighting spectra, Zeolite. Now some of my past observations make more sense to me.

With the push to go green, and attempts to legislate the use of compact fluorescent bulbs, lighting issues are going hit the radar screens of even the general public.

 

[Richard M.]

Hi,
This morning while our California fog cover was perfect for diffused daylight illumination, I tried a little experiment with a color change garnet. I first white-balanced my camera (Nikon Coolpix 4500) with a piece of white printer paper -- it was handy. Without changing white balance I shot the series of images below, with the stone resting on off-white Lucite.

From top to bottom the lighting was: natural diffused daylight, diffused "daylight" fluorescent rated at 6000K, and diffused incandescent from 4 clear 40-watt appliance-type bulbs in an overhead lighting fixture. I''m sure the colors would have been different with other artificial lighting of various CRI ratings.

Nothing was done in Photoshop except cropping, minor sharpening to overcome lens blurring, and airbrushing out a couple of pieces of lint.

The object here is to show consumers that lighting color change gems for photography can be very difficult and sometimes unintentionally misleading. The best way to judge c/c stones is in person. Mixed-light situations (i.e., natural light from a window combined with either incandescent or fluorescent lighting overhead) will change the colors moment to moment.

Richard M.

 

[LD]

Absolutely fascinating! Thank you so much for your replies. Also thank you to Zeolite for the offer - I agree, a private messaging system would be a great addition to this site - as would being able to upload photos from various photo websites with the facility to add videos. Interestingly I took a video of the Alex in the pendant above (in natural light by a window) then moved into the room under electric light and the video really shows the colour change. I do wish I could add it to this thread as I think it''s great for people to see colour change!

Once again, very many thanks for the informative suggestions.

 

[zeolite]

Hi Richard,
I''m about 100 miles south in the same coastal fog.

I took your method, setting white balance from a white sheet outside, and locked in that white balance, Then I shot 6 gems (in 3 successive posts), first photgraphed in overcast daylight, then using Excella full spectrum fluorescent bulbs (color rendering index [CRI] of 91). Then only some exposure correction, cropping and sharpening, no color correction in Photoshop.

I think this series shows that Excella is an excellent substitute for daylight. The overcast daylight is muted in color, low saturation, while the Excella is brighter, more lively. I think a better daylight condition would be full sun with white diffuser overhead. That would more closely match Excella. Can''t do that now, it is still overcast.

I still would say that these colors are not completely accurate, they only show what the camera thinks is the correct color, not what a critical eye says is the right color. No digital camera, which uses a set of red green and blue filters, can exactly match the colors we see with our eye.

 

[zeolite]

Overcast daylight left, Excella right

 

[zeolite]

Overcast daylight left, Excella right

 

[Lady_Disdain]

Date: 9/9/2008 6:39:23 PM
Author: zeolite

You could go to Adobe.com and buy Photoshop elements for $180. Or you could buy a Canon used digital SLR (DSLR) camera (one with interchangeable lenses), and get the Photosop Elements that is included with this camera. The used camera could cost $300-$400; the same camera sold new 4 years ago for $1500.

May I offer an alternative? GIMP is GNU license software (which means you can download it for free) edditing software. It has pretty much all the utilities in Photoshop (although some are downloaded seperately). It can be a bit fiddly at first, but it is not hard to use, specially with all the tutorials on the web.

 

[Richard M.]

zeolite,

Those images are really helpful. Thanks for taking the trouble. I have Excella tubes on order and will post my own results later. This has been a very interesting and informative discussion.

Richard M.

 

[PrecisionGem]

Color change stones are hard to photograph. One thing you want to do, as you change your lighting, reset your white balance on the camera so that the white back ground is white. Often you see picture of the stone when it looks blue with the background blue, and red, with the back ground red. This does tend to exaggerate the color change. The truest photo would have the same background colors. As always, it''s just best to see the stone in person.

 

[Fly Girl]

I apologize in advance for the threadjack ---

Welcome back to PS, PrecisionGem!!!

Threadjack over.

 

[Richard M.]

Date: 9/13/2008 10:07:57 PM
Author: PrecisionGem
Color change stones are hard to photograph. One thing you want to do, as you change your lighting, reset your white balance on the camera so that the white back ground is white. Often you see picture of the stone when it looks blue with the background blue, and red, with the back ground red. This does tend to exaggerate the color change. The truest photo would have the same background colors. As always, it''s just best to see the stone in person.

Gene, I surely won''t argue with your first and last sentences! As for images I''ve tried every possible white balance combination (I think!) I''ve heard the advice you give many times but nothing seems to produce consistently white backgrounds or the gem colors my eyes see. What kind of camera are you using for your cc gems?

Richard M.

 

[PrecisionGem]

I use a Nikon D70 for all my gem pictures. While the camera has several built in white balances, I use the program mode. With this, you just aim the camera a white piece of paper, so that the entire view finder is filled with the white paper, and make an exposure. The camera adjusts the color so that the white paper looks pure white. It will do this from everything from candle light to mercury vapor.

I also use Aperture on the Mac. This program will essentially do the same thing after the photo is taken. If I get a few minutes I''ll do it on some of the images in this thread.

 

[PrecisionGem]

Here''s one of the pictures from above, with the backgrounds color corrected

 

[zeolite]

Gene,

Below is a comparison of your white balance method with my "hold the gem next to my monitor and match the colors by eye in Photoshop".

The first (leftmost) picture is Excella fluorescent, setting the white balance with white paper. The next picture is Reveal incandescent, setting the white balance with white paper. I didn't get the white balances to match perfectly; that is quite difficult, even with multiple tries.

The third picture is taking the first picture and tweaking it in Photoshop, trying to match the picture on my monitor while holding the Excella light over the actual gem. The fourth picture is taking the second picture and tweaking it in Photoshop, trying to match the picture on my monitor while holding the Reveal light over the actual gem. Notice that the background color shifts away from white, as I apply the gem color correction to the entire picture.

If the goal is to match white backgrounds, your white balance white paper works well. If the goal is to make the picture match the actual gem, I think my method is more accurate.

While it is quite possible to take both white balance pictures, mask off the back ground, and apply color correction to only the gem, I consider that manipulation and not being honest to the viewer.