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Thread: The angle of light and image impact

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    Default The angle of light and image impact

    Following on Artie's post and the thread drifting, at jays suggestion I thought we might start a new thread. This one dedicated to the angle of light between you, the photographer, your subject, and the light source (often the sun).

    I have looked at a number of bird images on BPN and see some trends. I'm pulling out examples, mostly of white birds (or birds that have a lot of white) because you can see the effects of light angle more consistently. Please try and not be offended if one of your images shows up in the too flat category. If you went through my bird gallery, you can also pick out images that I would put on this (too flat) list.

    Phase angle is the angle between you and the sun as seen at the position of the subject. If your shadow points directly at your subject, there it little to no angle between you and the sun: the phase angle is near or at 0 degrees. Example, the full moon. Subjects lack shadows, but more importantly, the shadows are lacking in the fine details, e.g. the feathers on a bird, or the grains of sand on a beach, or the grain in a stick on a bush.

    As phase angle increases, shadows start to form. On curved surfaces, the light intensity drops, giving subtle shading and that we perceive as form in images. The subtle shading makes a 3-dimensional object look more 3-dimensional in a photograph (which is always flat).

    At very low phase angles, there is first surface reflection from the components making the subject, and first surface reflections have little color. As phase angle increases from zero, the first surface reflections decrease and color actually increases. This observation is for complex surfaces, like rocks and soils, tree branches and leaves, skin, hair, bird feathers, etc. it doe not apply to surfaces there there are large flat surfaces, like windows or calm water.

    As phase angle continues to increase, shadows become deep and images can become very contrasty. High contrast interferes with our perception of color and can push the limits of the recording medium (film or digital sensor).

    At high phase angle (approaching 180 degrees), the sun is behind the subject. Things that are small or similar to the wavelength of light scatter light a lot. For example, dust in the atmosphere, a cloud, or a person's hair. This is called forward scattering. Some subjects are translucent and let light shine through, for example, leaves in the fall, or light through a bird's wings. Usually, this transmitted light has greater color than reflected.

    These effects are all well explained by the physics of light called radiative transfer.




    BPN posted image that look too flat in my opinion due to a low phase angle:

    Down the barrel blue tit
    http://www.birdphotographers.net/for...read.php/77694

    Roller
    http://www.birdphotographers.net/for...read.php/77637

    The bird on the left appears particularly flat:
    Laughing Gulls
    http://www.birdphotographers.net/for...read.php/79360

    Leucistic American Coot portrait
    http://www.birdphotographers.net/for...read.php/77717

    Lesser Jacana
    http://www.birdphotographers.net/for...read.php/78758

    White-Tailed Kite
    http://www.birdphotographers.net/for...read.php/77918

    Mute Swan
    http://www.birdphotographers.net/for...read.php/78120

    White Ibis posing
    http://www.birdphotographers.net/for...read.php/78138

    Squacco Heron
    http://www.birdphotographers.net/for...read.php/78168

    Hooptie Deux Dunlin
    http://www.birdphotographers.net/for...read.php/78193

    Crested Tern
    http://www.birdphotographers.net/for...read.php/78201

    American Avocet
    http://www.birdphotographers.net/for...read.php/78202

    Give me a chip!!
    http://www.birdphotographers.net/for...read.php/78510

    Spoon-Reflection
    http://www.birdphotographers.net/for...read.php/78585

    Ring billed gull at super low angle
    http://www.birdphotographers.net/for...read.php/79366

    Calling Flamingo Red Shoulder
    http://www.birdphotographers.net/for...read.php/79393

    WTK
    http://www.birdphotographers.net/for...read.php/79572

    Egret from Last Summer
    http://www.birdphotographers.net/for...read.php/79595



    =========

    Images at higher phase angle that show form:

    Wonderful light off to the right, showing detailed form, beautiful! If the light were straight on (point your shadow at the bird) the image would not display the subtle forms and would lose its impact. (Image by Arash Hazeghi).
    White-tailed kite.
    http://www.birdphotographers.net/for...read.php/79164

    This is a portrait of a sandhill crane with a phase angle of 20 to 30 degrees by Troy Lin. The image shows wonderful form, texture, and color with great light.
    *Sandhill Crane Close Up *
    http://www.birdphotographers.net/for...Crane-Close-Up

    Nice diffuse side light showing form and detail:
    Bald Eagle stare-down
    http://www.birdphotographers.net/for...read.php/77647

    Very dramatic plus dark background (higher phase angle):
    Call of the Wild - Great Blue Heron
    http://www.birdphotographers.net/for...read.php/78548

    Here is an image with nice feather detail by Artie. The sun is off to the left about 20 degrees. We see a small shadow of the wing on the bird's body. I think the feather detail would have been a little better if the sun were another 10 degrees (about) further to the right.
    Nice Reflection.....
    http://www.birdphotographers.net/for...read.php/80944

    A little higher phase angle, looks about 60 degrees, but illustrates the form and texture that phase angles give.
    Another landing White Ibis.
    http://www.birdphotographers.net/for...read.php/80676

    Here the sun is 30 to 40 degrees off to the left. One comment was the shadow on the wing is a strong point.
    Squacco Heron
    http://www.birdphotographers.net/for...read.php/80488

    BUT compare the above image to image in the first section. the same species but near zero phase angle:
    Squacco Heron low phase angle: http://www.birdphotographers.net/for...read.php/78168
    Note the major difference in feather detail in the wings!

    Another nice image with feather detail and form. About 30 degrees phase angle
    Flamingo mocking Bird Morsel
    http://www.birdphotographers.net/for...read.php/79533

    The sun was above Artie when he made this image, but the phase angle looks to be about 20 to 30 degrees. The phase angle helped make the nice feather detail. From the direction of the feathers in the wings, if the sun were to the right the same phase angle, the feather detail would have been even more intense. Even so, the phase angle works well here.
    Blessed by the Sun
    http://www.birdphotographers.net/for...read.php/80869

    =========

    Phase angle probably too high (subject side mostly in shadow):

    Grey Headed Gull
    http://www.birdphotographers.net/for...read.php/78183

    =========

    Then 180 degree phase angle gets to silhouettes, which are often stunning.

    Penguin sunset
    http://www.birdphotographers.net/for...read.php/79463


    =========

    I couldn't tell what the phase angle was on this one, but the feather detail is astounding.
    Perhaps diffuse, overcast light, which is indicated by the discussion.
    Non-Baited Dalmatian Pelican :)
    http://www.birdphotographers.net/for...read.php/81061


    After reviewing these images, try imaging with the sun at different angles. What angles do you like best?

    Roger

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    Thanks for doing this, Roger.

    Very helpful to me, as a newer member here, to try more alternatives than just the "template" I might otherwise have followed a bit too religiously.

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    Super Moderator Daniel Cadieux's Avatar
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    This has the potential to be a great thread too...thanks for starting it Roger!

    I think we may have differing definitions of flat (at least for this subject). For me flat means "washed out" or very low contrast. Most of the "flat" images you refer to are fine in that department (enough contrast). I believe what you mean is more like lacking dimension because of missing or very few shadows? Not as "3-D"?

    Anyhow, my personal rule of thumb is to start off by pointing my shadow to the bird, and then I don't mind if it moves left or right a bit (imagine trying to keep up with a speedy Sanderling while lying flat on the beach). This gives me a wide area to cover in front of me before I quit a change my position or find another subject. Same goes for birds in flight...we can't keep up with them to keep the sun between us and the subject and as you demonstrate light that is not perfectly aligned gives great results for wing detail. The main important point when the bird moves away from sun angle is its head angle. When off light (even by a mere 20 - 30 degrees) I will take many less frames as I wait for the head to turn in a way that it is well illuminated, better than the body. Many of the images that you refer as having a higher phase angle would be doomed had the heads been angled differently (e.g. had Arash's flying kite looked right instead of left, or Charles' eagle looking left).

    Another point if I may. Even if the sun is directly behind the photographer, it is still higher above than the subject so in many cases you do have shadows forming from the light coming at a downward angle and not directly as a straight line (or else the photographer's shadow would be in the way)...I see many "low phase angle" images with a bit of a shadow under the bill, chin, belly as the sun rises higher in the sky (but not too high as to be harsh!!)

    To keep it short...I'm very open to going a bit off light angle (and more in some cases) and do it very frequently but will always start off placing myself, if possible, with my shadow pointing towards the bird and work from there. I like direct lighting very much and don't personally see them flat. A few of the "flat" examples you show I actually find quite appealing and a couple even have the "wow" factor for my tastes. A few of the higher phase angle images have the same Wow effect too...so whatever works go for it!

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    Roger,

    My mantra over my photo career - is one many in the industry have heard me say time and time again. I have written numerous articles on this very subject over the years.

    "Light Illuminates, Shadow Defines"

    Generally the greater the contrast the more I will point the shadow at the subject, as the contrast decrease the more I will place the light source off axis.

    The caveat being flash, whereby I can shoot off axis in high contrast situations I would never consider otherwise. It's all about ratios and subject modeling!


    Best,

    Chas

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    I looked at the first 5 of the "flat" list and the common light(ing) factor is that they are all taken on cloudy/overcast days.
    I looked at the first 5 of the "form" list and the common light(ing) factor is that they were all taken on sunny days.
    Agree? I think I may see a pattern here?
    Many wildlife photographers, especially birders, seem to prefer overcast/cloudy days. Because they don't like the "harsh" lighting of sunshine. So afraid of "blown out" whites ?
    As for myself, give me interesting/compelling light (whatever that is) first, before anything else.

    Tom

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    Quote Originally Posted by Tom Graham View Post
    I looked at the first 5 of the "flat" list and the common light(ing) factor is that they are all taken on cloudy/overcast days.
    I looked at the first 5 of the "form" list and the common light(ing) factor is that they were all taken on sunny days.
    Agree? I think I may see a pattern here?
    Many wildlife photographers, especially birders, seem to prefer overcast/cloudy days. Because they don't like the "harsh" lighting of sunshine. So afraid of "blown out" whites ?
    As for myself, give me interesting/compelling light (whatever that is) first, before anything else.

    Tom
    I looked at the first 5 again and disagree that all 5 were in overcast light. The first one may be overcast. But the others show sharp shadows and a pinpoint catchlight; definitely not overcast.

    And the last image by Artie in the list "Non-Baited Dalmatian Pelican :) " was on an overcast day and shows great feather detail.

    I agree with interesting/compelling light, but can we define what it is?

    Roger

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    Quote Originally Posted by Charles Glatzer View Post
    "Light Illuminates, Shadow Defines"
    Chas,
    This is a great quote. Seems to me I've read this or something very close in old photo books. Do you know the source?

    Roger

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    [QUOTE=Daniel Cadieux;649025]This has the potential to be a great thread too...thanks for starting it Roger!

    Quote Originally Posted by Daniel Cadieux View Post
    I think we may have differing definitions of flat (at least for this subject). For me flat means "washed out" or very low contrast. Most of the "flat" images you refer to are fine in that department (enough contrast). I believe what you mean is more like lacking dimension because of missing or very few shadows? Not as "3-D"?
    Daniel,
    The shadow giving dimension is part of it, but not all of it. It also includes fine detail and texture. For example, definition in the birds feathers. So the shadows are at all levels: the larger imparting form to the bird's body, but also on the fine scale increasing detail in the wings and feathers.

    Quote Originally Posted by Daniel Cadieux View Post
    Anyhow, my personal rule of thumb is to start off by pointing my shadow to the bird, and then I don't mind if it moves left or right a bit (imagine trying to keep up with a speedy Sanderling while lying flat on the beach). This gives me a wide area to cover in front of me before I quit a change my position or find another subject. Same goes for birds in flight...we can't keep up with them to keep the sun between us and the subject and as you demonstrate light that is not perfectly aligned gives great results for wing detail. The main important point when the bird moves away from sun angle is its head angle. When off light (even by a mere 20 - 30 degrees) I will take many less frames as I wait for the head to turn in a way that it is well illuminated, better than the body. Many of the images that you refer as having a higher phase angle would be doomed had the heads been angled differently (e.g. had Arash's flying kite looked right instead of left, or Charles' eagle looking left).
    I completely agree with head angle. Body angle can be important too. But for example, if head angle were perfect in two situations: one near zero phase angle, and one 20 to 30 degrees off, which would give the better image? Assume everything else equal, including foreground and background.

    I agree too that with wildlife we often do not have much choice. The birds is flying by so the angles are changing. But choosing where to stand can be important so that as the bird flies by, it is in the best position for the best image with the best light, and the choice that position should include consideration of phase angle.

    Quote Originally Posted by Daniel Cadieux View Post
    Another point if I may. Even if the sun is directly behind the photographer, it is still higher above than the subject so in many cases you do have shadows forming from the light coming at a downward angle and not directly as a straight line (or else the photographer's shadow would be in the way)...I see many "low phase angle" images with a bit of a shadow under the bill, chin, belly as the sun rises higher in the sky (but not too high as to be harsh!!)
    I agree, but generally light from above is not flattering to a subject. I will argue that moving to one side will make a better image, assuming equal head angle, foreground and background. Of course moving to one side will also increase the phase angle.

    Often we don't have a choice on position in order to get a clean foreground or background that we desire. But then the image may not be the top, as the light is critical too for the top images.

    Quote Originally Posted by Daniel Cadieux View Post
    To keep it short...I'm very open to going a bit off light angle (and more in some cases) and do it very frequently but will always start off placing myself, if possible, with my shadow pointing towards the bird and work from there. I like direct lighting very much and don't personally see them flat. A few of the "flat" examples you show I actually find quite appealing and a couple even have the "wow" factor for my tastes. A few of the higher phase angle images have the same Wow effect too...so whatever works go for it!
    OK, I'm fine with that. I'm interested to hear which ones in the first category give you a wow factor?

    Roger

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    If you are paying attention something can be learned on this site every day. I commented on an excellent

    chikadee image the other day ( Duane Noblic, "A Simple Chikadee" 3/11/11) and said that I had trouble

    with these birds' black and white head in direct sun. Arthur responded back to me that one of the keys to

    the detail in this image was "working right of sun angle" so then I had something else to think about.

    Several of you folks are good teachers and I appreciate your time and instruction. Thanks for posting this

    Roger and thanks for your input Daniel.

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    I meant working right on sun angle- not right of sun angle.

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    Quote Originally Posted by jack williamson View Post
    I meant working right on sun angle- not right of sun angle.
    For all: the image in question is:
    http://www.birdphotographers.net/for...read.php/81161

    I responded to Artie's comment about being on sun angle:

    But the posted image is not right on the sun angle. It is off to the right a good 20 to 40 degrees judging by the sharp shadows. The image shows wonderful fine detail, due to the sharp focus and a nice off-sun angle.

    Roger

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    Roger, terrific discussion. Personally, when I approach birds, I approach with the light on my back but, when shooting, dont necessarily limit myself to 0 phase angle.

    Bird and head angles are also important. We dont always shoot birds that are perfectly parallel to the sensor. That adds another dimension. Birds move and at times, we cannot. At times, when you are still and birds have come within reach( but moving about) changing position can result in missing the shot.

    In such situations, what I try to do is, based on how the light is hitting the bird, try to capture a good angle of the head and use the dramatic angled light to advantage.

    e.g.

    http://www.birdphotographers.net/for...hen?highlight=

    http://www.birdphotographers.net/for...ght?highlight=

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    Hi Roger. Thanks for replying to my response in detail! Here are a couple from the first list that are highly appealing to me:

    http://www.birdphotographers.net/for...read.php/78120

    http://www.birdphotographers.net/for...read.php/78138

    http://www.birdphotographers.net/for...read.php/78758

    The swan (first link) and the ibis (second link) both particularly have the slight shadows below the bill and/or neck and/or belly and for all three I never would think of wanting a sun angle a bit off of where it currently is. I'm sure if the sun angle was to the side by a bit I wouldn't have minded that either. Like I say, I'm open to a bit of variation...and more if the opportunity is good for it - see my recent Burrowing Owl:

    http://www.birdphotographers.net/for...ery-last-light.

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    Ok, re the lighting on first 5, my comment above. Will mostly agree except for number 3. I see no shadows of the gulls on the sand. Even strong sidelight would give shadows where feet and sand meet. And catch light in eyse, cloudy/overcast days will still give a catch light (I'd bet).
    As for what is "interesting/compelling" light, I know what I like, like trying to define "art"

    Tom

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    Quote Originally Posted by Daniel Cadieux View Post
    Hi Roger. Thanks for replying to my response in detail! Here are a couple from the first list that are highly appealing to me:

    http://www.birdphotographers.net/for...read.php/78120

    http://www.birdphotographers.net/for...read.php/78138

    http://www.birdphotographers.net/for...read.php/78758

    The swan (first link) and the ibis (second link) both particularly have the slight shadows below the bill and/or neck and/or belly and for all three I never would think of wanting a sun angle a bit off of where it currently is. I'm sure if the sun angle was to the side by a bit I wouldn't have minded that either.
    Hi Daniel,

    I think the three images are very good too, and I particularly like the third image. But I would wager that if each of these birds had been photographed with a little greater phase angle, it would have raised them to a higher and more impressive level.


    Quote Originally Posted by Daniel Cadieux View Post
    Like I say, I'm open to a bit of variation...and more if the opportunity is good for it - see my recent Burrowing Owl:

    http://www.birdphotographers.net/for...ery-last-light.
    This image is really spectacular!!! The two things I would do with it. 1) brighten the shadow on the eye as suggested in the comments to your image, and 2) there are some strange artifacts from bokeh in the background, I would blur those a little. But these are minor to an overall great image. (and the phase angle helps here too )

    Roger

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    Quote Originally Posted by Tom Graham View Post
    Ok, re the lighting on first 5, my comment above. Will mostly agree except for number 3. I see no shadows of the gulls on the sand. Even strong sidelight would give shadows where feet and sand meet. And catch light in eyse, cloudy/overcast days will still give a catch light (I'd bet).
    As for what is "interesting/compelling" light, I know what I like, like trying to define "art"

    Tom
    Hi Tom,

    If you look at rhe gull on the right, you can see sharp shadows cast by the right wing onto the body, and from the body onto the left wing. The shadow of the right bird's leg is faintly visible, but a ridge in the sand blocks further view. The shadow from the legs of the left bird is also visible. The low sun altitude means there is a lot of fill light from the blue sky making the shadows light. The shadow of the wing on the left bird shows the sun is a few degrees high and the sun was to the right with a phase angle around 10 degrees.

    Roger

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    Quote Originally Posted by Kaustubh Deshpande View Post
    Roger, terrific discussion. Personally, when I approach birds, I approach with the light on my back but, when shooting, dont necessarily limit myself to 0 phase angle.

    Bird and head angles are also important. We dont always shoot birds that are perfectly parallel to the sensor. That adds another dimension. Birds move and at times, we cannot. At times, when you are still and birds have come within reach( but moving about) changing position can result in missing the shot.

    In such situations, what I try to do is, based on how the light is hitting the bird, try to capture a good angle of the head and use the dramatic angled light to advantage.

    e.g.

    http://www.birdphotographers.net/for...hen?highlight=

    http://www.birdphotographers.net/for...ght?highlight=
    Kaustubh,

    I agree that head and body angle are important, and more important than phase angle. If the head were tilted away, then in most cases, the image would not work regardless of phase angle (except possible a silhouette near 180 degrees phase).

    I like both your images. Both have a small but significant phase angle. I'm wondering if a slightly higher phase angle would have improved the feather detail a little. But it is very good as is. And the head angle, position and composition are well done too. Very nice.

    I'm not sure what exactly the optimum phase angle is. I think there is ample evidence on BPN that it is not the very low values. And the optimum may be different depending on the bird and its feather structure. And it may be different for wildlife and fur structure. But what I'm seeing, I think 20 degrees is getting to the sweet spot on many birds, and perhaps 30 or 40 degrees.

    So for those who want to try it, instead of approaching with your shadow exactly pointing to the bird, try just a little off. It might help to get a protractor, as 10 or 20 degrees is a relatively small angle. And consider that as the sun gets higher in the sky, the phase angle is increasing too. Then which way to approach (right or left)? I would make that decision based on the head angle, body angle, and best foreground and background.

    And for those who really want to explore this issue, try photographing the same subject at a few different phase angles in a short time interval. It would very instructive to see these results.

    Roger

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    Quote Originally Posted by Roger Clark View Post
    For all: the image in question is:
    http://www.birdphotographers.net/for...read.php/81161

    I responded to Artie's comment about being on sun angle:

    But the posted image is not right on the sun angle. It is off to the right a good 20 to 40 degrees judging by the sharp shadows. The image shows wonderful fine detail, due to the sharp focus and a nice off-sun angle.

    Roger
    Thank you Roger for the message concerning this image. I'm not sure where you would like me to post the shooting information so I guess I will just post it here.

    This image was taken in Chesapeake, Virginia at around 4pm in the afternoon on March 7, 2011. As I stated in the topic I think I was working with a very thin layer of clouds and the sun was over my left shoulder at the time.

    As others have stated I try to keep my shadow in front of me but with this discussion I learned a few things concerning light angle and the height of the sun.

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    Quote Originally Posted by Duane Noblick View Post
    Thank you Roger for the message concerning this image. I'm not sure where you would like me to post the shooting information so I guess I will just post it here.

    This image was taken in Chesapeake, Virginia at around 4pm in the afternoon on March 7, 2011. As I stated in the topic I think I was working with a very thin layer of clouds and the sun was over my left shoulder at the time.

    As others have stated I try to keep my shadow in front of me but with this discussion I learned a few things concerning light angle and the height of the sun.
    All,
    It is very simple to compute the position of the sun or moon using this web site:
    http://aa.usno.navy.mil/data/docs/AltAz.php
    (Note also the data services tab gets other useful data.

    On this web page, you simply put in the date, and for US places select the state and nearest city. The site does not correct for daylight savings time. For other places in the world you need longitude and latitude (you can get that from google earth).

    Here is the portion of the table for Duane's image around 4pm (16:00) EST.

    Altitude and Azimuth of the Sun
    Mar 7, 2011
    Eastern Standard Time
    Azimuth is (E of N)

    hhmm altitude azumuth in degrees
    1530 28.4 237.9
    1540 26.7 239.9
    1500 24.9 241.9
    1600 23.2 243.8
    1610 21.4 245.7
    1600 19.5 247.5
    1630 17.7 249.2
    1640 15.8 250.9
    1650 13.9 252.6

    (I had to take the : out of the times as funny characters kept getting inserted.)
    So the sun was abut 23 degrees high at 4pm (1600), and since the shadows are to one side (say about 15 degrees), the phase angle was around 27 degrees (25 to 30).
    From the time of day and shadows, we also know the camera was pointed north-east.
    It is the phase angle of about 25 to 30 degrees that gives the wonderful feather detail.

    Roger

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    Good topic Roger. Sorry I'm a bit late here.

    If "flat" light is defined by the images Roger showed in the original list, I love it, 100%. What appears to be the case is that phase angles either side of 0°, so long as they are not too great, are also good because they reveal what you could call "micro" detail. As the phase angle approaches 90°, the shadows and highlights form big areas of the image, which you could call "macro detail". I do not like 90° phase-angle side-lighting in wildlife portraits for the most part, but I'm am always open to the possibility. Then as the phase angle becomes > 90° you are into backlighting situations which sometimes work and often don't.

    I like the idea that phase angle and head angle interact and essentially have to be taken together.

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    What's the "translation" you applied to the altitude/azimuth sun charts, Roger? And does that differ by coast?

    I just got the LightTrac app, and am psyched to apply that app to a number of my birding sites. LightTrac gives the sun elevation in degrees, so I want to figure out how I take that data to get what you did, for optimal light/phase angles.

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    Quote Originally Posted by Allen Hirsch View Post
    What's the "translation" you applied to the altitude/azimuth sun charts, Roger? And does that differ by coast?
    Allen,

    I'm not sure what you mean here.

    Quote Originally Posted by Allen Hirsch View Post
    I just got the LightTrac app, and am psyched to apply that app to a number of my birding sites. LightTrac gives the sun elevation in degrees, so I want to figure out how I take that data to get what you did, for optimal light/phase angles.
    Does it give azimuth too? If one has never been to a site, with google earth or a map, I suppose one could find a location and knowing the direction one would photograph, one could determine if if morning or afternoon might work best. But unless you can only stand in one spot, it seems to me that local variables, like where the subject is located, how it is facing, and what the foreground and background are determines from where and the direction one points the camera. From that I would determine if there was flexibility on position relative to the sun and thus the phase angle. Certainly a lot needs to come together to make a great image, not to forget head and body angle, and because of all those details, it seems to me that being on site trumps any pre-visit calculations of sun position beyond general directions.

    Having said that, for my son's outside weddings (2009 and 2010), knowing the date, and location of the event, I computed the sun position to confirm that the time of the ceremony was OK. We did push the time of one event later because I computed a shadow would be crossing the gazebo at their initial chosen time. That shadow was cast by a hotel roof. In the end it didn't matter as it was cloudy.

    Roger

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    Thanks to everyone for the enlightenment. Especially Roger

    Ray

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    Thank you Roger.

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    Late to the party. I did not read the whole thread as as most of you know, I am not a scientific/technical type of guy. I am glad that many found it interesting and that many learned from it. Off to Midway soon.
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    Thanks Roger!
    Very informative post. Will definitely be more mindful of this the next time I'm out photographing.

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