This one has been giving me trouble for a while, COLOR!!! I'm starting a big shoot this week and in the last days have got new calibrating software (Spyder Pro 2) and calibrated my laptop, what a difference. Now I've got all my lighting spread out in the hotel room shooting a color checker card with my P30 while tethered to the laptop. I was unable to rent a color meter so my question is can you shoot a color checker to figure out your lights color temp? Also, when doing so should the color temp be the same thru C1 Pro when clicking on the gray or white space on the card, they are several hundred degrees apart. As for my new ring light from profoto is showing a color temp of 5050, when it is supposed to be 5400. It is brand new out of the box could this be right?

Any tips are appreciated on how to figure out the proper temp of each head, combing elinchrom and profoto?

Attached is the shot with the Profoto ring light, when I clicked on the gray spot it read 5050, is the correct, all lights were off in the room.

Regards,

Ben Edmonson
www.benedmonson.com

Yes you can use the grey patch to set the WB. It is not uncommon for lights to have a slightly different temp than given in the spec's. My Elinchroms are all less than stated (4900K vs 5000). Anything you put in front of your lights will even lower it more. The temp will also change when the lights get warmer. Reflections from the space you are working in can also alter the temperature which is why several standardization organisations advice neutral grey for the room to cope with that.

Best patch to use I find the grey patch, the white patches pollute a bit faster with other colors especially when you take the card under an angle. You will find that sometimes clicking in the same patch but at different places can give you slightly different results as well (within about a 100K and sometimes a lit bit tint/green/magenta difference as well).

I own a color meter, while it is a very handy tool to start understanding what actually happens it also learns you quite quickly that it is fairly useless. Light temp varies throughout the place you are working. Temp can vary several hundreds of degrees even while using just one light. I find it much easier to work with color charts.

You have calibrated your screen, use a grey/color chart. Next step might be to calibrate your camera (sensor). When you are not printing yourself this is about it what you can do. I noticed Michael placed a small article about this on the site just recently. While you can get the very expensive Gretag camera module software there are other free/cheaper solutions as well apparently.

There seem to be two approaches to color

accurate and film like

for example 'accurate' if you were shooting tungsten you would correct the yellow cast out 'film like' you would leave it in

film like can look nicer say on a building at sunset where the yellow windows can be considered appealing

I think you need to do some shots for you 'main light source' or variants

Shots like 'ring card' or 'elly card' or 'sunny card' or 'cloudy card'

These shots need to be done in a very neutral environment

Which you then save and paste those reults in C1 onto your shoot shots

I think using a gregtag card during shooting can be an insurance but is ultimately flawed becuase say you have a room with red walls they will cause a red cast that you dont want to get rid of

I also wouldnt trust a laptop screen calibrarted or not

After RAW there is also chromaholix which I think is a PS action to get a shot of a card 'perfect'

So

Go to a grey space, shoot your card with your lead light

Create a setting in C1 with that grey balance

Save the image to PS

Run chromoholix on it

For your shots use that C1 setting and follow it with that cromoholix action and you should get perfect images for that light source

Even if the images are of an orange in a red room

----

My experience however is that none of it works but using your own eyes to tweak each individual image

And if you are delivering a set then you need to tweak with the other ones open to keep consistency across the set

Good luck

SMM

Ben,

Digital color is hard. Color is to digital what exposure is to film - a constant headache where every approach brings advantages and drawbacks.

You need a good calibrated screen to see what you're doing. Current laptops don't quite cut it, unless you have a desktop screen to check against when necessary.

For people photography purposes what you really NEED is a decent color balance. Put a colorchecker in the actual shot lighting, have the model hold it on set.

In C1 you then define the whites by clicking one of the grey squares of the colorchecker. Click around a bit on those until the image looks good, and You can then tune the white balance manually

After that the selected profile does the work in C1; the Phase One profiles for their own backs are very good; I don't think that if a back is in spec one would be able to do better in practice with a casually lit location shot and a simple colorchecker. Of course if one doesn't have a good profile it's a different game and the colorchecker calibration procedure may be the best bet for people with Adobe Raw.

The above applies to people photography; product or repro photography may require other more precise techniques, but these wouldn't necessarily make a fashion shot look better.

Edmund

Digital color is hard because digital color is just a huge pile of numbers and numbers alone don't fully define color.

Ben,

I've done several tests with my Profoto lighting and a colormeter. Each strobe was slightly different, but by only 50 degrees Kelvin or so. I've never had any issues with color balance
when shooting. I would also watch the age of your flashtubes. Color temp. can change as
they age.

Chris Lawery
Sales Manager
Capture Integration
www.captureintegration.com

This brings up something I've been thinking about lately. Does anyone have a good estimate as to how often to replace flashtubes? I had a light crash down from a lightstand wedged in a bathtub doing an interiors shoot a few weeks ago and need to replace it. All of my other tubes are about 2 years old. Should I replace them all? Or just the broken one?

chromaholix?

Is this the correct name?

Where can one obtain this PhotoShop action?

Thanks to all.

Joe Bossuyt

http://fors.net/chromoholics/

To myself I say if it's not broken. don't fix it. I do preventitive maintenance on some items (cameras, shutters, etc.). I carry spare batteries to replace dead ones and flash tubes to fix blown or broken bulbs. But I don't replace them to head off failures.

Since you need to replace one of them, I would replace the rest.

I had so much problems with using tubes of different ages that there was always some slight color cast in the shadows due to temperature differentials. I measured all the heads I had with my colormeter and decided this was not working efficiently.

My view is to have all of them replaced at the same time to get consistent output.

Henry

I would agree with Henry. I would replace them all at the same time to have a consistent color.
It may cost a bit, but may be worth the grey hair you would get from trying to color balance. I might save the old flashtubes as back-ups.

Chris Lawery
Sales Manager
Capture Integration
www.captureintegration.com