Camera help: Gold coin turning out Copperish

All,

I can't get this tiny little bugger to smile gold for the camera... any settings that could possible help me?

 

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Yes! Put the slab in a vise and keep turning the handle until it gives.

Chris

 

Gold is tricky to light properly. I've gotten the best results from using indirect light. You can also get some better color by reducing the brightness and increasing the contrast a little in post processing. The goal is to get the picture to look like the coin does in hand.

Here's an example. I reduced the brightness and increased the contrast slightly. If you combine post processing adjustments with lighting adjustments you can get it to look quite nice. Also if your camera has a white balance calibration make sure to take advantage of it.

 

Jaelus,

Sorry the close up is the one I am having trouble with.

 

What type of lighting are you using and what are your camera settings?

 

Using Soft white CFL and White Balance is on Tungsten.

 

A soft white bulb is going to be yellow light around 2700K. Tungsten white balance is going to be around 3500K. Do you have a better stock option or an actual white balance calibration option where you can use a reference card?

Also you'd be surprised how much light you actually need to get the best color. I used to shoot with a pair of CFLs outputting 800 lumens each and it wasn't anywhere close to enough light. I'd end up with shots that were too dark and the color would be off and not fixable with post processing. The bulbs I use now are outputting in the ballpark of 5500 lumens each.

 

Wow. You are a genius when it comes to photography (and im a bit buzzed). What bulbs do I need to buy then to make it easy?

I have a Canon Powershot G16 if it helps

 

You might set your white balance to fluorescent light rather than tungsten, just to see how it looks. It should be closer than setting it on tungsten...

 

Before you buy anything else, the absolute best advice I can give you is to buy this book and read it cover to cover: Numismatic Photography 2nd Edition by Mark Goodman. The money you spend on this book will improve your coin photography way more than anything else you could possibly spend it on. Trust me on this.

As for bulbs if you search for CRI 90 5500K bulbs you'll find ones that will produce good color. 5500K is the color temperature (daylight range) and the CRI is the Color Rendering Index which is basically how accurate the light is at illuminating an object at the same color your eyes see it as. Anything 90 and above for CRI is excellent. Keep in mind different types of bulbs are going to have pros and cons though. You don't want a bulb that's going to light your coin perfectly but run so hot it melts your camera! Also keep in mind the wattage of the lamp you are using. Again, all of this stuff is in the book. If you haven't bought it already, go buy it right now! I'll wait.

 

First of all, the coin's too dark because the lights are too low. Move the lights closer to the camera (a higher lighting angle). You have a ways to go before the glare impinges on the coin. I would also consider the advice to crack it out of the third world slab. White balance looks pretty close to accurate. You might want to bump the saturation a touch, but see how raising the lights works. Keep the coin in hand as to you do this so you don't overdo it.

 

I'll look for the book.

I found these bulbs.

http://www.lightbulbsdirect.com/SpiralFS5500K/48923FS.html

It looks like its 5500k but only pumps out 1200 Lumens.

Will they work? Keep in my they need to fit in a lamp

 

My experience with photographing Gold is the coins made for circulation or coins that are not 999 pure (24k) tend to have a copper hue due to other alloys in the metal. In this shot of a 20 Franc Rooster I am using a Sony Rx100 mIII point and shoot and simply cheap clamp on light fixtures found at Walmart with some GE Reveal bulbs....

 

It's going to be a step up from what you are using, but you will need a lot of illumination. You can always use additional lamps if you need to.

 

Went out this weekend and found these:

http://www.homedepot.com/p/EcoSmart...l-CFL-Light-Bulb-4-Pack-ESBM814450K/205487810

but 100W... think lumens are 1400.

Light is way "whiter" than the GE Soft whites I had. I assume I should use "Florescent" on my White Balance?

 

You should start with daylight for the white balance with these bulbs, but you may need adjustments from there. Best thing to do is to calibrate your white balance using a grey card. You can also use a piece of white paper, but it has to be white and not yellowed at all. I use daylight-balanced compact fluorescents for all of my work.

 

I'd like to add as a lighting specialist. The color of an object as illuminated by a light source is directly related to the CRI ( color rendering index). Incandescent light sources all have a 100 CRI. The reflected color you see is the color it is. CFL bulbs have a less than desirable CRI, typically around mid 70 - upper 80's. All fluorescent bulbs have a 3 number listed i.e 741, 750, 835 etc. The first number is the CRI, the second is the color temperature from lowest 2700 (incandescent warm) to 7000 very white with some blue ( color of sky at high noon on a cloudless day). LED can also be a good source, but very few with a CRI over 90 so far.
With all that useless info, the higher the CRI to 100 and adjusting the camera settings will give you the best chance at the true color.
Good luck

 

Blast....these bulbs only have 82 CRI.... oh well, I will have to play around and see the results.

Thansk for the tip.

 

Seriously, go buy that book and read it. It's a lot cheaper than buying a ton of bulbs you don't like...

 

When doing a custom white balance, how good is the camera at compensating CRI? For instance, if you had a source with a CRI of 20, which would probably indicate extreme spikes or troughs in some part of the spectrum, how well can a digital camera compensate with custom WB?