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Actually, I'm not a big fan of north window light; it's too often a bit weak. I suggested: "you might take one of the problem gems outside and shoot it in bright open shade, as a test to see if that produces the correct color.  If it does, your problem might well be your lights." 

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It does sound like your bulbs should be good but generaly there are large gaps in the spectrum from cfl lights. One of the really bad parts of the cfl spectrum output is the blue/purple areas there is a very narrow spike in the blue areas with lots missing on either side of it. As an cheap experiment I would go down to your local hardware store and get a few full spectrum incandescent bulbs and shoot a few comparisons shots between that and the cfls you are using.

-Philip  

Good suggestion on the incandescent bulbs, Philip.  I take your word for it about the gaps, I wouldn't know.   I would think, though, that they'd be too hot for my softboxes.  I sure don't want a fire or to ruin the fabric of it.  I need diffuse light, to keep the reflections at a decent level and not blown out.  I'm not having any problems with the blues, though.  And out of probably 100 or more purples, only 3.

 

Ed, Martin, I did try a north window in the beginning. But the jewelry needs evenly lit, so if I put my back to the window, I blocked the light.  If I set up parallel, one side was lit better than the other side, even with a reflector.  I have a picky-picky boss.  I don't want to invite do-overs, as this involves a certain amount of crouching over and arranging the jewelry just so, which is hard on my bad spine.  Plus if I have to shoot a whole set over, my hourly is cut by half.  Not an option. :)

 

 

I agree with Ed. I was not suggesting that you use natural light to shoot the job rather you use it as a quick test to see if it is your lighting set up that is creating the colour discrepancy.

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So I was doing some digging about spectrum response of light sources. What I came up with is when its available I would look at the induction light bulb from the finally light company (http://finallybulbs.com). Induction lighting in general has a better spectrum curve than fluorescent bulbs. 

The interesting thing I found is the term full spectrum is marketing gibberish and doesn't indicate the quality of the light. What one is looking for from a lighting source is a smooth curve across the visible spectrum without large peaks and valleys. Todays incandescent bulbs have a good spectrum curve while fluorescent and led have some sever peaks and valleys. I was hoping to find out what places that do art reproduction use but I was unable to find anything solid. I would imagine that someone doing art reproduction of the masters would have the same issues as you. Some colors of paint were created by crushing gems and so they will reflect very narrow spectrums of light similar to what is happening to you in some of the jewelry you are photographing.

One final source of information I found was Robert Weldon who is the manager of photography for GIA (Gemelogical institute of America). He has done a few articles (jck magazine about lighting for gems/jewelry. One of his papers specifically mentions that fluorescent bulbs have an uneven spectrum (read peaks and valleys). The article I saw was written 17 years ago, before incandescent became banned so it is of limited help. He has a linked-in ( www.linkedin.com/pub/robert-weldon/89/4b2/832page  that you maybe able to use to get in contact with him to get some advice on lighting and best practices for photographing gems/jewelry.

 

The x-rite passport should help but may not be the complete solution. I would still look to replace your light source when you can. 

 

This kind of problem brings out the obsessive compulsive geek in me so I have to keep digging until I have a solution.  :)

-Philip

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Got it.  I ordered the x-rite passport today, it should be here Saturday.  I dread learning how to use it.  I'm overworked and underpaid. Oh. I'm overworked and well-paid. B)

 

Betty

 

It's easy Betty.  However remember that you are viewing colours on a screen (Imac) which will not give you the whole ARGB spectrum, so it's not about colour critical but colour 'approximate'.

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Philip, thanks so much for your trouble.  I understand a bit how you are, I've been known to get a hold on something and not let go until it thundered.  My family calls it bullheadedness occasionally, but we are who we are. 

 

Geoff, my friend, (who has bailed me out more than once) thanks for the encouragement.  If you say it is easy, then it is so.

 

Wiskerke, I sold my strobes (Alien Bees) last year.  I do have SB800s, but it would take me a month of Sundays to figure out how to set them up. Everything I read about shooting jewelry says a continuous light source is best.  I look through the viewfinder and what I see is what I get, I can make adjustments (exp. comp) by turning a dial as I look and see the exposure change. Granted, if I could find a cool continuous light source without using fluorescent that would be the perfect storm. 

 

What about LED?

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...

 

 

What about LED?

It seems LED will be the way to go and many photo lighting companies are offering them, video has been there for a good while. Whether the technology is ready yet for critical work at an affordable price is another question. I have seen comments that (some) LED lights may not have a smooth, continuous spectrum so could cause similar issues to fluorescent (probably with different colours). Might be case of borrowing/hiring a set and trying them when you are ready.

 

I face that dilemma, my strobes failed recently so if I want to do studio work I need new lights. Do I need flash or would continuous be easier? Need to understand my business plan and what I can afford first.

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Philip, thanks so much for your trouble.  I understand a bit how you are, I've been known to get a hold on something and not let go until it thundered.  My family calls it bullheadedness occasionally, but we are who we are. 

 

Geoff, my friend, (who has bailed me out more than once) thanks for the encouragement.  If you say it is easy, then it is so.

 

Wiskerke, I sold my strobes (Alien Bees) last year.  I do have SB800s, but it would take me a month of Sundays to figure out how to set them up. Everything I read about shooting jewelry says a continuous light source is best.  I look through the viewfinder and what I see is what I get, I can make adjustments (exp. comp) by turning a dial as I look and see the exposure change. Granted, if I could find a cool continuous light source without using fluorescent that would be the perfect storm. 

 

What about LED?

 

Betty,

 

There's a video linked earlier about setting up/using the colour passport. It is as easy as it looks. I have mine set up for LR, I can export a dng and then use the export> function for the X-rite software to do it's thing and the profile is then in the dev module.

 

Personally I doubt this is the whole answer, neither would new lights be. Sometimes you just have to do local colour matching - selections plus colour changes (by whichever method you want).

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Philip, thanks so much for your trouble.  I understand a bit how you are, I've been known to get a hold on something and not let go until it thundered.  My family calls it bullheadedness occasionally, but we are who we are. 

 

Geoff, my friend, (who has bailed me out more than once) thanks for the encouragement.  If you say it is easy, then it is so.

 

Wiskerke, I sold my strobes (Alien Bees) last year.  I do have SB800s, but it would take me a month of Sundays to figure out how to set them up. Everything I read about shooting jewelry says a continuous light source is best.  I look through the viewfinder and what I see is what I get, I can make adjustments (exp. comp) by turning a dial as I look and see the exposure change. Granted, if I could find a cool continuous light source without using fluorescent that would be the perfect storm. 

 

What about LED?

 

Betty,

 

There's a video linked earlier about setting up/using the colour passport. It is as easy as it looks. I have mine set up for LR, I can export a dng and then use the export> function for the X-rite software to do it's thing and the profile is then in the dev module.

 

Personally I doubt this is the whole answer, neither would new lights be. Sometimes you just have to do local colour matching - selections plus colour changes (by whichever method you want).

 

 

OMG, Geoff, I didn't think about selections!  I'll have to try that.  I agree about new lights.  I already spent more than I like for this gig, even though the money is good.  What I don't want to do is buy so much stuff (like the passport) that it eats into my profits. 

 

Yes, I want to do a good job.  But this isn't Rolex hiring me.  It isn't even Swarovski.  It's a dentist buying old jewelry, some with scratches, and converting it to pendants and earrings with wires instead of clips.  He has bought a lot of it, and frankly, if this doesn't sell and become popular, he'll have a 2nd mortgage to pay off. He is now having me shoot the more expensive "few of a kind" that is quite beautiful.  None of it is true gemstones, it is all costume.

 

That said, if his website bombs, and if his Dallas show in a week or so bombs, I'll be out of this job.  Which in a way would be a relief.  I like the money I'm making, but it is eating up my life at a time I should be working less and not more.  Plus he is getting quite demanding.  I don't care to go the ulcer route again.

 

I'm not sold on dng, I like to keep mine RAW to Tiff, then to jpeg.  Can I still do that or does it have to be dng with the passport?

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I'm not sold on dng, I like to keep mine RAW to Tiff, then to jpeg.  Can I still do that or does it have to be dng with the passport?

 

 

You can stick with your current workflow. If you install the X-Rite LR plugin, you can create a camera profile from a raw file image which contains a shot of the passport target using an Export preset that X-Rite provide. Once you've made the camera profile, close and reopen LR and then the new camera profile will be available on the camera calibration tab. 

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I just tried to see what was on the CD that came with x-rite passport, and the CD keeps being rejected.  Won't open.  The xrite site says they recognize there is a problem with Macs. Said something about creating a new user with admin account on Apple, supplied a link, but I don't see where to do that.

 

AAAARRRRGGGGHHHH!   I KNEW  this wouldn't be easy for me.  Everyone else?  Yes.  Not me.  OK, pity party done, :) any suggestions?

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You bailed me out again, Geoff.  I downloaded it. Then it wouldn't open.  Wonder of wonders, I figured out how to change my security settings so I could open and install it.  Now I get to figure out where to find it and what next to do!

 

Thanks!

 

Betty

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404 error on that link Allan

 

Here it is.

 

It's not too bad. The comments run the gamut.

There's a link in there somewhere to someone who describes his ways to get perfect skin tone. Not bad at all!

 

The description in Steve Davey's article about the two light sources profile (Dual-Illuminant) is a bit simple. This works the best with two continuous spectrum light sources, usually bright sunny daylight and ordinary incandescent house lamps (a threatened species). And this is exactly how Photoshop's own profiles (and probably all the others) work. They calculate the in between values, and approximate the values that are outside the in between graph.

 

For light source other than a continuous spectrum light source, you would ideally make another profile.

 

Even for strobes, which of course are designed to be very close to sunlight. (This is why some studio photographers have their strobes marked with their color compensating filter settings.)

For the modern outlandish fluorescent light sources like daylight lamps or leds, it's an absolute necessity, unless you have a CRI of 98 or so.

(A necessity only for those who need or want color accuracy of course.)

 

wim

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I have shot some passport images. Not sure if I did it right, because somewhere in a video, someone said to fill the frame with the passport, yet today what I read said don't fill the frame, but have it at least 10% of the frame.  Oh well.

 

I spent an hour studying how to go about making it all work, and hopefully tomorrow I'll see if I can muddle through it.  Geoff, for you, easy.  For me, not quite so.  Lots of steps involved, but I took notes and usually that's all it takes for me is to get through it one time.  I'm quite eager to see how it affects the images!

 

Trouble is, I have no jewelry to shoot.  My boss is off to market with every piece he owns, so it will be possibly two weeks before I can see if the purples work.  I did take a couple of pics with a purple and the passport before turning the jewelry back to him. I'll check those, but wish had more to experiment with.  I can always try something besides jewelry, I guess.

 

Betty

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Betty,

 

This is the type of shot I take with the passport - daylight with one of my lenses.

IMG_6268.jpg

 

I keep the image in a folder and then just export to x-rite passport in second export menu and job done. The profile is then in the LR module.

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404 error on that link Allan

 

Strange it was working. Sorry.

 

Allan

 

 

If you look higher up, I already gave the correct link and some comment.

Must have been a tiny fault, but cannot remember what it was.

 

wim

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Betty - it could be a colour temp issue of your lighting? Are al lthe flash bulbs new, any dying? I've had colour shifts before from aging bulbs in my Elinchroms.

 

Bulbs are new, the lights were purchased for this job.  Color temp is daylight, but I've yet to use the x-rite color passport to see what that does.  Looking forward to seeing if that fixes things.

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