Harsh light

[Ray Rozema]

I would like to understand better what is meant by harsh light and how it affects the image. I understand at mid day the light can be too strong and from the wrong direction. I have seen comments the the "lighting is too harsh". What do you see in the image that indicates the lighting was too harsh? how can one lessen the negative impact of harsh light?

Thanks very much

Ray:)

[Alfred Forns]

Hi Ray

We mean light that is strong and causes the range from highlights to shadows unable to be recorded by the camera. Like film the sensor can only record a certain range. On the other hand, during early morning and later afternoon the range is not as much and can be recorded.

Another aspect of harsh light is the Temp, more bluish in color, late day or early day light is warmer and more pleasing.

To lessen the impact of harsh light ..... go out earlier or later in the day ... or pray for clouds !!! Use of fill flash will help with harsh light during the day but you need to know what you are doing !!

[Fabs Forns]

Harsh light shows very hard contrast and shadows, very easy to tell. It's always from the wrong direction because the sun is very high in the sky and can't be behind the photographer unless you are photographing the ground.
If you absolutely must photograph in that light, reducing the contrast in post-processing using an inverse curve (see tutorial in the Educational Resources Forum), but it will only alleviate the situation, not make it good.

HDR and infrared photography both benefit from the high contrast present at noon.

[Roger Clark]

<tt>Ray,</tt>
<tt>Good question and the subject is often misunderstood. Harsh light has nothing to do with intensity and everything to do with directionality, both the angular size of the light and the direction it comes from. When the sun rises, for example, it goes through a thick atmosphere, about 30 to 40 times the equivalent thickness as compared to directly overhead. That has two effects: absorption changes the color of the light and haze and dust scatters the light so it comes from greater angles. Also the low sun illuminates the sky (e.g. blue sky or haze or clouds) and that light diffusely illuminates the subject.

As the sun rises, the atmospheric thickness decreases so the absorption of blue light decreases as does scattering (lessens), so the light becomes more directional. In a very clear sky (no clouds or haze) the dominant light source is from the solar disk, 1/2 degree in diameter.

Most subjects, whether scenic mountains, wildlife, or people look better with side lighting as compared to overhead lighting. On people, overhead light casts shadows in the eye sockets, making people look like their eyes are sunk into their heads.

I am working on an article about lighting, which in my opinion, is poorly covered in photography books. Here it is so far:
http://www.clarkvision.com/photoinfo/lighting.composition.subject

Next I'll be adding a series of images on flowers. Flowers in my opinion look best in totally diffuse light.

Roger</tt>

[Alfred Forns]

Hi Roger I have never seen Harsh low intensity light !!! :) Low intensity light coming from any direction does't seem harsh ... btw do understand what you are saying and looking forward to the article, do give us a heads up when finished !!!!

[Roger Clark]

HDR and infrared photography both benefit from the high contrast present at noon.

Fabs,
I disagree with the above. Perhaps you meant to say HDR can help cover the high contrast of directional sunlight. But IR wavelengths sees sunlight even more directional because there is less scattering in the atmosphere. So directional light can be bad for both HDR and IR photography. But then some subject can be dramatic with deep shadows, so there are always exceptions.

Roger

[Dave Phillips]

the other problem beside dynamic range in harsh light is cross color casts from one object to the other.....IMO.

The dynamic range is inherently in the subject and not the light....the light just brings it out

[Mike Tracy]

<tt>Ray,</tt>
<tt> When the sun rises, for example, it goes through a thick atmosphere, about 30 to 40 times the equivalent thickness as compared to directly overhead......

As the sun rises, the atmospheric thickness decreases so the absorption of blue light decreases as does scattering (lessens), so the light becomes more directional. In a very clear sky (no clouds or haze) the dominant light source is from the solar disk, 1/2 degree in diameter.
</tt>

Please explain why if the distance is constant between earth and the sun a rising sun has to travel through a thicker atmosphere at sunrise and less so as it rises.

Thanks.

[Roger Clark]

Hi Roger I have never seen Harsh low intensity light !!! :) Low intensity light coming from any direction does't seem harsh ... btw do understand what you are saying and looking forward to the article, do give us a heads up when finished !!!!

Alfred,
On the next full moon try this experiment: At noon in a clear blue sky photograph a scene, then near midnight photograph the same scene with the moon high overhead. Your exposure will change and moonlight is warmer than sunlight (because the reflectance of the moon is slightly red). But the scene will have about the same shadows and contrast, yet the intensity is many stops different. The "harshness" will appear about the same.

The confusion comes from the sun is less intense near sunrise and sunset, but that is not the reason for less contrast. Contrast is independent of light intensity.

Roger

[Roger Clark]

The gory details:
http://en.wikipedia.org/wiki/Airmass

I'll try and find a simple diagram.

Roger

[Roger Clark]

This one has a simple diagram:
http://pvcdrom.pveducation.org/SUNLIGHT/AIRMASS.HTM

[Mike Tracy]

This one has a simple diagram:
http://pvcdrom.pveducation.org/SUNLIGHT/AIRMASS.HTM

Got it ! Appreciate your time.

Does the solar constant change based on latitude and seasons or is it a average ? Sorry to pick your brain for whats to you remedial questions.

[Alfred Forns]

Hi Roger

Will try experiment at the next full moon !!! Will take some time with the diagram I'm always interested in learning about light !!

[Steve Canuel]

http://www.birdphotographers.net/forums/showthread.php?t=20192

[John Chardine]

Great topic and thanks for the insight Roger. So put another way, you want omni-directional light so that some of it will find its way into the dark nooks and crannies of your image, and this type of light is produced morning and evening and in cloudy conditions. I like it!

[Fabs Forns]

Fabs,
I disagree with the above. Perhaps you meant to say HDR can help cover the high contrast of directional sunlight. But IR wavelengths sees sunlight even more directional because there is less scattering in the atmosphere. So directional light can be bad for both HDR and IR photography. But then some subject can be dramatic with deep shadows, so there are always exceptions.

Roger

Roger,

At 8Am, I don't really need HDR.

[Roger Clark]

John,
Exactly. I like what I call "puffy cloud days" with nice blue sky with a few scattered white puffy clouds. They make sunsets interesting, and when the sun is higher they add light in the shadows.

Roger

[John Chardine]

John,
Exactly. I like what I call "puffy cloud days" with nice blue sky with a few scattered white puffy clouds. They make sunsets interesting, and when the sun is higher they add light in the shadows.

Roger

Also winter at higher latitudes in the N and S hemispheres would produce less harsh light, better still if there's snow on the ground!

[Ray Rozema]

Thanks for the information very helpful.

[Charles Glatzer]

Most define "harsh light" as light that creates a clearly defined shadow edge. The transition edge from light to dark (contrast) has much to do with the size of the light source relative to the subject, as well as diffusion, etc, and not the quantity of illumination.

A full moon on a clear night is a point source, as is direct sunlight. While the moon lit image will require longer exposure, as it is lower in intensity than direct sunlight, the resulting image will have hard shadow edges. Add a thin cloud layer or position the moon or sun lower on the horizon and the shadow edge will become less defined.

In the studio we always choose first the quality of light, modifying the source as desired, and then the quantity.
Working in a studio enviroment will greatly enhance your lighting knowledge base.

Due to a request ... I recently gave an indoor multi-strobe and strobe/ambient outdoor portrait presentation during a wildlife (loon '09) workshop. All present stated the lesson greatly helped them to understand lighting fundamentals, especially ratios and directional control.

If you truly want to become the best photographer possible, you need to fully understand how light quality, quantity and direction work together to create the scene before you.

Best all,

Chas

[Roger Clark]

Chas,
Good post. I agree 100%.

I have a web page on lighting that I'm still developing and adding examples to, but it is pretty far along:
http://www.clarkvision.com/photoinfo/lighting.composition.subject

Roger

[Roman Kurywczak]

.........If you truly want to become the best photographer possible, you need to fully understand how light quality, quantity and direction work together to create the scene before you.

Best all,

Chas[/quote]
That line says it all! Quality, quantity, & direction. Agree 100% Applies in all situations.....indoor,outdoors, sunny, overcast, day,night, moon, moon phases, flash, multiple flashes, etc., etc., etc. Nothing more complicated than that. Understand the light and situation and learn how to deal with it to your best advantage.