Correcting for Tungsten Lighting in Photoshop

What is the best way to correct for shots taken in tungsten lighting

with daylight film? My blue channel is very dark and grainy, so

anytime I try to bring up the blue or bring down the yellow, I get

unnatural results (crossovers, etc.). Is it best to just leave these

images as they are?

 

Here is an example. Please be kind; this was a very rough scan.<div></div>

A little more information about this shot. This was taken with Portra 800, and scanned on a Canon FS4000US at low resolution using Vuescan. The Vuescan settings were set to White Balance (setting the software to Tungsten wasn't any better).

Let me turn you on to professional secret: <A HREF = http://www.pixelgenius.com> PhotoKit</A> . this is a Photoshop plug in that has numerous digital darkroom tools -- color correction, color conversion, color to black & white (in many different filter emulations -- three different types of sharpening -- dodging & burning, grain (film effect) etc --, is infinitely flexible in the strength and combination of theses tools. while you can build all of the actions included, which is more valuable to you:hours of work or $50.00?

Would it be possible for you to take the photo and do a little color correction with that software package? Thanks.

Hmm, your neg looks familiar.

 

I recently ran a test with Portra 800 (rated at 640, pushed half a stop) under tungsten lighting, and found that there was insufficient density to yield a fully corrected print in a traditional darkroom. I got about half way there with taking out the tungsten cast, and the final prints were acceptable - but in future I would not rate this film any higher than 400 under tungsten. I think that Fuji Superia Xtra 800 and NPZ offer a little more leeway in these conditions.

 

Re. Photoshop - I found that in Photoshop I could correct my Portra 800 negs a little bit better than in the traditional darkroom. First by using 'levels' in the individual channels - and then using the burn tool to knock down any remaining bluish shadows. But I'm sure there are better ways...

Use a four layer film with tungsten; or an actual tungsten film if possible. When scanning a negative like Robert's; boost the blue channel alot before scanning; in the prescan software; and the green just some. This will reduce some of the noise from the blue channel when the image is corrected in Photoshop. Also shooting a color patch at the start of the photos allows one to get a color correction alot faster. Here is Robert's photo modified in Photoshop 5.5 using only the curves; boosting the B,G, and R channels manually in different amounts. The shadow areas get noise; because they are way underexposed; and underscanned in the blue channel.. <BR><BR><IMG SRC=http://www.ezshots.com/members/tripods/images/tripods-377.jpg>

The shadow area could be retouched to remove the blue speckle noise pixels; but this is a slow go and consumes WAY too much time.

A natural alternative, if the color balance gets tricky to do, is to convert to B&W. I do this sometimes with color digital images when I have too much mix between tungsten and daylight to make either one look good.

So here's the latest: I used the curves tool to dial down the yellow (by bringing up the blue). Then I used the Magic Wand to select all the dark clothes and dialed them down the black (or near black) to get rid of the noise. Here's the result. (Better than before, no?)<div></div>

Yup, it looks better.

 

(By the way, your Jpeg is tagged with your Photoshop working-space (Adobe 1998). This means that, unless you're using Internet Explorer 5 for the Mac (with Colorsync enabled), your Jpeg is going to look different here on Photo.net than it did when you were fixing it in Photoshop. (It will look kinda washed out when you post it here.) If your destination is the web, you should convert your image to sRGB before saving as a Jpeg.)

You know - main problem is your shot is tad underexposed. If you would like to compensate, overexpose at least 1/f under tungsten. Otherwise you have next no information in blue channel = nothing to work with.<br>

$50-$100 82C filter = No $50 plugings, no retouching, and close to correct color ballance, costs 1.2/f of light only.

Robert,

 

if you use "selective color correction" in PS you get, what I go in the attachment.

 

Enjoy!<div></div>

Yes the blue channel is very dead; boosting it too much gives alot noise in the shadow areas of the womens dark outfits. <BR><BR>With my film scanners and flatbeds; I get much better results by doing the massive corrections BEFORE scanning; in the prescan software; by boosting the BLUE alot and GREEN somewhat. The better prescan softwares alot one to save these settings; so the prescan setings battle is only needed for one negative; if the lighting is similar. After scanning; then I do the minor color corrections in Photoshop; and get alot less noise in the shadow areas. When I did this on some color negatives from 1944; the results were major league radically better.

If this is a critical shot, AND you can't rescan to increase the amount of data in the blue channel (it's almost nil now), the best solution I can think of requires some channel blending and some LAB corrections.<p>

<ul>

<li>Copy the file and convert the copy to LAB mode.

<li>Switch back to the original file and select the Blue channel

<li>Image > Apply Image and specify the L channel in the LAB copy as the source, and the Blue channel in the original as the destination. Set mode to Normal, and try about 20-50% That'll put <i>something</i> into the blue channel. It's not 'blue' information, but we can adjust that later.

<li>Discard the LAB copy

<li>Duplicate the original again, and convert the copy to LAB mode. Adjust the B channel to get more neutral colors--more saturation than normal is OK (I moved the ends of the curves in evenly, offsetting the neutral point).

<li>Convert the copy back to RGB and do the final tuning.</ul><p>

Note 1: if you have to shoot with daylight film under tungsten lighting, and don't have a blue filter, over-expose! That'll give the blue layer a chance to register any information. As it stands, the blue is probably 2 stops underexposed on-film, and that's hard to recover. Depending on the film, +1 or even +2 stops may be best to avoid problems later.

Robert,<P>Absolutely, Imagine being able to set if for 1/2 of a 81 filter, of somewhere between an 81 A and an 81B, etc. if you are really good and know how to use selecctive masking and layers you could color correct or color balance just specific areas of your image. Or go somehere between a full clor version of an image and a full grayscale version.

Another approach to correct Tungsten Lightning could be the following steps: <br><br>

 

- dust & scratch removal on the blue channel<br>

- duplicate the background layer<br>

- increase the saturation of the blue channel to 100%<br>

- blending mode "negativ multiplication" (=> blue casted image)<br>

- color balance (=> light yellow tone)<br>

- hue correction (=> whites get almost white)<br>

- channel mixer (=>"perfect" colors) ;-)<br>

- correct the hue and saturation of some speckles on the women's dresses<br>

- a little bit of gaussian blur<br>

- unsharp mask<br>

<br>

and the result is in the attachment! <br><br>

 

 

IMO, the sample image looks now good but since it's very small it's hardly possible to judge if this proceeding really leads to an acceptable result.<br><br>

 

It might be worth trying. :)<div></div>

How about making a copy of the boosted blue channel, using strong noise reduction just on that channel and then relying on the other channels to provide detail?

<i>"Here is Robert's photo modified in Photoshop 5.5 using only the curves; boosting the B,G, and R channels manually in different amounts. The shadow areas get noise; because they are way underexposed; and underscanned in the blue channel.." Mar 09, 2003; 05:26 p.m.</i><BR><BR><img src="http://i4.photobucket.com/albums/y148/ektar/PNretouch/tripods-377.jpg"><BR><BR>I reposted the lost image from 2003 that was once hosted with www.ezshots.com; which died.

Alex; using CS2 one can use "reduce noise" on the blue channel; which is typically the noisy one in a tungsten shot. Noise often appears in one channel such as BLUE more than another. Under "reduce noise" try the "advanced" position instead of basic to fiddle with just Blue; by fiddle I mean the "Strength and Preserve details sliders" this came out in CS2 in 2005; after this thread was basically asleep.

<p>I hear using a blue filter will do the trick</p>