Paul C. Buff, Inc. Technical Forum

Hi -

This is my first post and I freely admit I may ask questions that sound like I dont have much experience with strobes......that would be a correct assumption. I apologize in advance if my questions seem, well......clueless :lol:

I have my Einsteins set for daylight, 5600K. I shoot with a Canon 5D MK II in RAW format and in AdobeRGB color space. Yet when I import my files into LR5 (MAC) version, my images come in at 5200K. From everything I read before purchasing my Einsteins, I thought the color accuracy of these were supposed to hold very tight to 5600K.

What am I missing? Wrong settings in LR? Bad Einsteins? Bad Photographer?

Thanks in advance for your advice!

Robert

There is a lot that goes into measured color temperature. Typically, a consistent temperature from shot to shot and power level to power level and light to light is of more importance than the actual color temperature.

The color temperature of Einstein is 5600K, however that is without the dome in place (and it is perfectly OK to use it this way, if a specific 5600K color temperature is a higher priority). The dome will drop color temperature by 200-300K (or right into the middle of the variance range of Alien Bees and White Lightning).

Additionally, any modifier you use will affect color temperature, as will the environment (colored walls, floors, etc). I have also tested a variety of camera and lens combinations, and few match each other. Filters and camera profiles will compound the problem, as will the white balance target you are using.

Bottom line, in actual shooting conditions, you are likely not to get 5600K, regardless of the actual flash tube. For best results do a custom white balance for each lighting condition you are in.

TS,

Thank you for that explanation!

Robert

Actually, Einstein™ produces 5600K at the flashtube, but the Pyrex dome lowers this to about 5400K. But there is a bigger issue . . . all cameras and White Balance cards are not created equal, nor are color meters. I've bought every color meter made, at #1000+ a crack, and they disagree with each other by up to 1000K, and each will give you a totally different reading if you move in or out from the flash a few inches.

Now, for cameras: I'm away from home and my old standby D300 Nikon. So I bought a Canon xt3 to do some shots. Horror of horrors, all my 5600K shots came out 6400K with a lot of green cast, color fringing and other evils.

So I bought a D7000 Nikon. The 5600K shots now came out 6000K, but no color fringing, but still green cast.

So I bought a Passport color calibration set. Profiled the Nikon. Made the pix pop more, but didn't change the recorded white balance or the green cast. New high pixel sensors - bah humbug - my old Rebel V1 was fine. Figured out how, using DNF Profile editor to set the white balance to 5600K - 0 M/G. Caveat ; Einstein™ does vary a bit in Magenta/Green tint over the power range, but not much. Also, we're finding that most flash tubes drop in color temperature as the get used a lot.

Feeling lost and tired of buying crap, I bought yet another Nikon D300(s). Bingo . . . back to what I'm accustomed to - 5600K 0 M/G tint correction.

The point is, what's a couple hundred degrees K from a little company like mine when the billion dollar companies can't agree within 1000K?

Also, any fabric modifier you put on any light is likely to shift color down by 200K, with bad ones shifting it up 1000K due to fluorescence.

Then, of course, there's the matter of shooting environment. Walls that appear white can throw your white balance off by several hundred K.

My studio away from home is very dark neutral grey (to eliminate unwanted bounce) and my shooting wall is the result of testing several color patches from the paint companies, comparing them to my WhiBal card (The standard IMHO), then still custom mixing the paint to get within 50K of the WhiBal card.

Oh. another thing . . . try a color card with several shades of "neutral grey" including Monaco, Kodak, etc. Whenever I do this, I get up to 300K ore more between the greys.

I've been fooling with this stuff for 20 years and am still to find an absolute color temperature standard better than my D300 and an absolutely neutral room.

The main thing with Einstein™ is that you can vary the power anywhere between 640WS and 2.5WS and expect +/-50K color balance consistency. With other lights, including the biggies, you can expect a 400K shift from power adjustment of only 600WS down to 19WS.

Boncolor Scoros and a couple other $10,000+ IGBT systems can achieve Einstien's color accuracy, but they'll still give you up to 500K measured variance depending on what what balance card and camera and modifiers you choose.

Hope this help . . . 20 years of testing condensed to a few dozen sentences.

Thank you Paul for the additional insight!

This stuff isn't bad, though not perfect and probably not as good as your custom mix and way too expensive :)
http://www.bhphotovideo.com/c/product/2 ... Paint.html
I have a pint of it on my projector wall and it's not a perfect match to a Whibal, but fairly close (probably 100K?)
Reeks when you put it on though :(

Sherman Williams "Seal Grey" is pretty close. I had Lowes mix to this formula and had them add a little extra Red, and got within about 75K. The Lowes mixer suggested I use "cheap paint" to get a flatter, non gloss finish than more expensive paints. He was right - $14 per gallon.

Im confused, you said the lights were set to 5600K and your camera colour space but not actually what white balance your camera was set at ? which I assume will have been 5200K hence the reason it shows up as 5200K in LR.

LR doesn't interpret what the WB is in the physical image (the flash) and transpose that to the slider, it takes what the WB is set to in the camera (hense the file)

If you used an in camera white balance of 3200K it wouldn't jump to 5200k in LR because thats what you think the lights are at dude, it would show up in the file/LR as 3200K it would just visually be different.

Make sense ? So set your camera to 5600K, it'll show up in LR as 5600K and match the lights perfectly.

If you shot with a camera set at 3200K white balance, it would come up as 3200K in RAW viewer (maybe - depending on which camera). But the color on screen would be extremely bluish and unusable.

Using the eyedropper tool on a reference card in the shot would make the colors right in RAW viewer and reveal the actual color temperature received at the camera sensor from the light(s), modifiers, and stray room color shifts.

I'm with Willmcgphoto, I was thinking the exact thing as I was reading the full explanations for LUAP.

Assuming your not shooting a grey card, white card (for canon shooters), or color checker, the light output color is irrevelant if you are not matching the white balance on your camera to the light your using. The camera WB is what your importing in LR, not the light temp.

Personally I hardly ever use auto WB. If I'm shooting flash or strobe, I set my camera to flash WB if I can't or don't have time to do a custom WB. I shoot Canon 7D and 5D III and never have color problems in my images unless I get lazy or forget to set WB. But shooting RAW as you do, it's an easy fix in LR.

Canon I believe are around 6000K for their speedlites so using a 5400K-5600K color lights as in the Einsteins and using the flash WB on your camera will give you a very slight warm cast, that's a good thing in most portraits IMHO. I don't trust my eyes on my monitor even when calibrating it. I don't use an expensive, color acerate monitor, I use my Macbook. I trust the histogram for exposure in LR or PS and my Camera WB for color. My prints come out beautiful. If I screw up and need to adjust in raw my color temp, I almost always err on the warm side. Not too many images look good with a cool, blue cast.

But if you need/want absolute color accuracy, spend the money to get the passport color checker and profile your camera/s... Than photograph it before every shoot. This way you don't need to calabrate your monitor and printer to your monitor. What you see may not be what your getting unless everything is calibrated. If you use a print lab, than they are out of your control as far as color so find one that you can trust. Most good labs allow you to ask for no adjustments if you trust yourself.