Blue Haze

[mike.online]

Hi all,

I'm wondering If you could help me out with something that has been nagging me for quite some time.


I'm on a contract as a GIS (geographic information systems and science) professional in Ethiopia right now. I often travel to do field work into some of the most spectacular places and views (there are a lot of large amount of mountains, given the rift valley). Being a photographer, this is pretty awesome.

However, Being Ethiopia, being between Somalia, The Sudan and Northern Kenya, I'm often not in a position to get to these remote vista's pre-dawn or at sunset. Thusly I'm stuck taking pictures during the day when conditions are far from ideal.

Most of the time the problem is wrangling the highlights down to a level where I can pull the blue sky back into an image. more or less I'm constrained by my 30D's sensor on that issue (I don't have a set of ND filters yet and I don't enjoy HDR all that much).

But, my real question and problem is haze. Haze kills my photos. It degrades the contrast and casts a blue filter over all distant objects. All of my lenses have UV filters on them, but not much help there. I've been using LR2 to process my photos and playing with all of the basic controls (black point, local contrast, grad filters) as well as the HSL sliders as well.

What do people generally do about haze, other than going early and late (which just isn't possible for me) in the day? what post techniques are best? any magic bullet?

Thanks,
- Mike

[francois]

Hi all,

I'm wondering If you could help me out with something that has been nagging me for quite some time.


I'm on a contract as a GIS (geographic information systems and science) professional in Ethiopia right now. I often travel to do field work into some of the most spectacular places and views (there are a lot of large amount of mountains, given the rift valley). Being a photographer, this is pretty awesome.

However, Being Ethiopia, being between Somalia, The Sudan and Northern Kenya, I'm often not in a position to get to these remote vista's pre-dawn or at sunset. Thusly I'm stuck taking pictures during the day when conditions are far from ideal.

Most of the time the problem is wrangling the highlights down to a level where I can pull the blue sky back into an image. more or less I'm constrained by my 30D's sensor on that issue (I don't have a set of ND filters yet and I don't enjoy HDR all that much).

But, my real question and problem is haze. Haze kills my photos. It degrades the contrast and casts a blue filter over all distant objects. All of my lenses have UV filters on them, but not much help there. I've been using LR2 to process my photos and playing with all of the basic controls (black point, local contrast, grad filters) as well as the HSL sliders as well.

What do people generally do about haze, other than going early and late (which just isn't possible for me) in the day? what post techniques are best? any magic bullet?

Thanks,
- Mike

Hi Mike,
I'm not an expert in PS but I would use a Hue/Saturation layer with a mask. You could decrease blue saturation and restrict your modifications to blue haze zone via a layer mask.
In Lightroom you can adopt a similar technique with the adjustment brush. Use the saturation and the color features of the brush. If you paint your hazy zones with the "opposite" color of blue (something like amber or yellow) you might improve the situation. It's not easy, though.

Expert PS users will certainely provide deaper, faster and more effective ways to fix your photos.

Sometimes, a polarizer filter can help to reduce haze…

[new_haven]

Can you post an example?

[EduPerez]

Yes, atmospheric haze can be a pain in the ass. A polarizing filter helps a lot, and during post-processing you can improve the image, too: raise the contrast and the saturation, then correct the colors using curves. Hope this helps.

[Ed Blagden]

I'm afraid that this is just something you have to live with when you are at high altitudes near the equator (believe me, I know).  Personally I find that the light before 9am and after 4pm is workable in Kenya, but I guess that is a matter of taste.  But between those hours, forget about it.  It's not just the haze, the contrast can be a big problem as well at altitude.

I don't use PS, but my experience is that there is not much you can do about the blue haze in LR.  You can always try developing in B&W, that sometimes produces a nice result.

Ed

[EduPerez]

[Sorry, this did not belong here]

[mike.online]

Can you post an example?

Before
[attachment=18238:mme_9182_3.jpg]

After
[attachment=18239:mme_9182.jpg]

[francois]

Before
[attachment=18238:mme_9182_3.jpg]

After
[attachment=18239:mme_9182.jpg]

Mike,
Your "after" try is quite good. The only things I would try: decrease blue saturation in the distant mountains and use curves to increase contrast in those same areas. I doubt that you'll get huge improvements, though. Keep in mind that I'm not an expert…

[new_haven]

I think this is an improvement. I opened your image in adobe camera raw and used the clarity slider too increase local contrast. For this image I also used fill light to brighten the figure. I believe I also used the recovery slider. Then, once in photoshop, I looked at the individual channels and saw much more detail in the red channel than the green and blue channels.

Duplicate the image (background layer) and change the blend mode of the top layer (background copy) to luminosity. Use the apply image command to copy the red channel of the background layer to the top layer. So we are using the background layer for color and the top layer for contrast and detail. I also applied the shadow/highlight command to bring up the shadows.

If you want to try this method and have any other questions, just ask. Oh, and I also sharpened.

Hope this helps. -R

[francois]

I think this is an improvement. I opened your image in adobe camera raw and used the clarity slider too increase local contrast. For this image I also used fill light to brighten the figure. I believe I also used the recovery slider. Then, once in photoshop, I looked at the individual channels and saw much more detail in the red channel than the green and blue channels.

Duplicate the image (background layer) and change the blend mode of the top layer (background copy) to luminosity. Use the apply image command to copy the red channel of the background layer to the top layer. So we are using the background layer for color and the top layer for contrast and detail. I also applied the shadow/highlight command to bring up the shadows.

If you want to try this method and have any other questions, just ask. Oh, and I also sharpened.

Hope this helps. -R


 

More seriously, I think that you've extracted almost 100% of the details contained in the posted photo.

[mike.online]

Wow, your method also revealed quite a lot of dust spots.  

More seriously, I think that you've extracted almost 100% of the details contained in the posted photo.

Tell me about it... the dust spots are another problem... but one easily solved with a static brush.

also the method (while intense) does seem to work quite well! I'll be trying that out with the raw data.

[new_haven]

All channels are not created equally. By looking at each channel, we see that most of the haze and garbage is in the blue channel. Let's just get rid of it.

Once the raw file is opened into photoshop we type Ctrl-j to duplicate the background layer. This technique combines the detail and contrast data from the top layer with the color data from the bottom layer. Set the blend mode of the top layer to luminosity. Now, we can replace the blue channel in the top layer with the red one without affecting the colors in the bottom layer. Use the image > apply image... command to copy one channel to another or a channel to a layer. Copying the red channel to the top layer will replace both the green and blue channels with the red.

This is also a good workflow for sharpening. -R