Trouble Shooting Colors

[dave_fritz]

<p>I have a Nikon D40X with the standard 18-55mm Nikor lens on it, I do fire appratus photography as a hobby (though with that camera it is sort of an expensive hobby LOL). Two weekends ago we were shooting in Greensboro, Pa whose fire appratus is painted in a really, really fantastic metallic teal color. I proceeded to take my pictures and review them and much to my surprise (and huge disappointment) found that they were not coming out teal but this shade of blue. Did I do something wrong that it didn't take the color correctly? I was shooting on full manual at F8 and an ISO of 125. Below is my picture and a picture shot with a film camera to show the correct color. What do you guys think?? Is it possible that the Nikon cameras can't process/reproduce teal??</p>

<p> </p><div></div>

[dave_fritz]

<p>Duplicate Post</p>

[dave_fritz]

<p>Now here is how mine came out:</p>

<div></div>

[photo5]

<p>Color reproduction is a science, and it depends on a lot of factors. One is color space, Nikon has two, Adobe RGB and sRGB. Both should be able to reproduce teal. Another is your monitor. Is it a true 8 bit display? Most LCD panels are not true 8 bit displays, but 6 bit displays that use dithering for the remaining 2 bits of information. Also, did you shoot in RAW format? This is important, because you can tweak the white balance in post processing to finesse your color. And what was the weather? The color of light illuminating the subject will have a direct affect on the final image. Did you use flash? Can you go back and re-shoot this object?<br>

I see the samples now. Your second image is shot in sunlight, the first is shot in cloudy weather. If you add some green and yellow to the second image you'll probably see more teal.</p>

[dave_fritz]

<p>Sorry was having problems uploading it.. you will have to click on the two attachments. The weather was bright and full sunshine (the only way our group photographs fire trucks.. with direct sun on the front and driver's side). I have NO clue what my color space is set on, I have never even seen the place to change that.... same goes for shooting in RAW format. I am still pretty new to digital photography. The subject was lit with direct sun so no flash was needed, the object is about 4 hours away and it will be awful tough to reshoot it. Thank you for your response!!</p>

[woolly1]

<p>It looks to me as if you may have set the white balance incorrectly. I see no distinct shadow line under the vehicle in the 'Correct Color' photo. Were you using Auto WB? Were both these photos from your camera?</p>

[howard_m]

<p>were you shooting w/ automatic white balance? did you by chance check the per-channel histograms to see if perhaps you blew out an individual channel?</p>

[woolly1]

<p>Howard may be onto something ... you may have clipped one of the color channels. I'm sure you can't see them on the camera, only the white histogram .... did you shoot RAW?</p>

[dave_fritz]

<p>I was shooting with auto white balance, do you think that messing with the white balance would have made a difference? As noted my picture was shot in perfect and full sun and the other one was shot in overcast (something that I have NEVER considered shooting in)...I have some other pictures at home of this same piece shot in a higher ISO setting (up to 400) and the picture gets darker but the truck remains blue. I wonder if the reflection is to bright from the mettalic teal for the sensor and it just can't see the green in direct sunlight but CAN see it in overcast.... hmm....</p>

[woolly1]

<p>Dave, can you post the original file here? We can look at the exif data.</p>

[dave_fritz]

<p>I can tonight when I get home at 19:30 (EST)... unfortunutly I don't have it here at work with me.. but if you are willing to look at it I will post it first thing when I get home!!!</p>

[howard_m]

<p>I dont think it' a white balance issue. the other colors look pretty close to what you'd expect. In LAB space, the blue is pure 0A,-50B</p>

[john_deerfield]

<blockquote>

<p>do you think that messing with the white balance would have made a difference</p>

 

</blockquote>

<p>Of course. That is what white balance is: the color of light. Daylight vs overcast means different light color temperature. Of course daylight is very hard light whereas overcast is very diffused, but in this case I think it's all about the white balance.</p>

[Jerry_]

<p>A suggestion: go to a local (Wal-mart?) paint department and get several small color-match paper hand-out pieces of paper. Then go into the sunshine and shoot several groups of the color boards. That will give you some input as to what colors your D40x handles to your liking. [The samples <strong>ar</strong>e <strong>free</strong> for the taking....]</p>

[peter_mounier]

<p>I'm with Howard M, I don't think it's a white balance problem either. The colors in the rest of the picture are fairly accurate in both of them, except the color of the truck. I'm guessing that the problem is with the paint. If it's metallic, that is, bits of reflective metal infused in the paint, then perhaps the "bad" color is because the truck is reflecting something blue, maybe the sky, which is gray in the "proper" color pic. In addition, in the "proper" color pic the color gets more teal, or green as your eyes scan from the front of the truck to the rear. I think the 1st pic is reflecting some green forest as suggested by the reflections in the rear window. Also, the first pic probably didn't have a polarizing filter on the lens, and the second shot probably did, (noticing the glare in the windows of both pics). And, some films are made to be more saturated in some colors, as opposed to being neutral. The film pic also looks a little too contrasty for a cloudy day, so maybe there's some overexposure going on, then compensated for in the scan or print. And finally, if it's indeed the paint, maybe there's something in the paint that film can see, but our eyes aren't sensitive to. So I think it's reflections, polarized light, possible overexposure in the first pic, and the inherent difference between film and digital.</p>

<p>Peter</p>

[JDMvW]

<p>If you take your second picture into PS, it is clearly deficient in yellow. Why? I don't know.</p>

<p>BTW, if you would reduce the picture to 700 pixels wide instead of 800 and post a caption to the picture, I think the resulting images would be just as good as posting them slightly wider -- and they would display directly in the post instead of having to shunt off to the side.</p>

[bnelson]

<blockquote>

<p>As noted my picture was shot in perfect and full sun and the other one was shot in overcast (something that I have NEVER considered shooting in</p>

</blockquote>

<p>You might try shooting it on an overcast day just to compare. If you look at the sunny picture, the teal is being picked up in the painted wheel rims at the back wheels, which are not in the bright sun. Looks like it is the paint.</p>

[joe_c5]

<p>Without a .raw file there is no way to be certain the camera did not just process the data wrong, but it looks like the camera’s spectral response curves for green and blue are not a close match with the response of our eyes, or even similar to the color film.</p>

<p>The paint on the fire truck probably also has a peaky spectrum, making it less likely that the color comes out close to correct despite the mismatched curves.</p>

[andy_j]

<p>Did you have a UV or polarizing filter on the lens?</p>

[stanleys]

<p>Using Hue/Saturation in photoshop I got this. Minus 14 on the hue slider.</p><div></div>

[dave_fritz]

<p>Holy Crap!!! That is the EXACT color it is in real life in that sunshine... amazing work. Is there a way to make my camera do this now?? Also, how did you adjust the hue/saturation of just the truck in Photoshop?? I am scared of photoshop and don't really know how to work it LOL... I have a couple more pieces from that same station that I would like to change to the right color.</p>

[dbcooper]

<p>Might want to check the color saturation settings in the camera then. Make sure they're set as neutral as possible. Might also want to clean the sensor - I see loads of dirt spots in the sky.</p>

[stanleys]

<p>Do you have photoshop? If you do, it's easy.</p>

<ol>

<li>open the image (ctrl+o, and browse)</li>

<li>open the hue/saturation box (ctrl+u)</li>

<li>grab the hue slider and adjust to taste (I used -14)</li>

<li>save the image (ctrl+s)</li>

</ol>

<p>As for your camera, I would use the WB presets (sun,cloudy,tungsten etc) instead of the automatic. The results of the AWB can be hard to predict.</p>

<p>Stan</p>

[gkgerber]

<p>Your Auto white balance may have gotten fooled by all the blue in the scene. For the next time around you may want to try the shots with your camera white balance set to Daylight instead of Auto. Even better, you could dig out your manual and figure out how to set a custom white balance under the prevailing lighting conditions. You should still check the color channel histograms in camera to make sure you haven't blown out one color channel. I would be surprised if you didn't get the nicest colors with a custom white balance under an overcast sky.</p>

[fhmillard]

<p>If you use Photoshop, create a curves adjustment layer, select the white "dropper", click on a white area in the image, set blending to luminosity, adjust opacity so the white part of the histogram is not blown out. Luminosity blending does not affect color tonality -- too much.<br>

And when shooting you can use a white, gray, black "card" in the scene; use those for white, gray and black in curves adjustment layer -- this is similar to the earlier suggestion using paint patches (but be careful inside stores since light temperatures are variable; so, choose paint patch like "titanium white".)</p>