Photographed @ Grand National Roadster Show, Pomona, Ca. 2009Uploaded by Swanee 3 on 3 Feb 09, 7.28PM CST.
Friday, February 27, 2009
Friday, February 13, 2009
Wednesday, February 11, 2009
Cascada nocturna
Cascada nocturna
El río Tinto por su paso por Nerva. Gracias x todo muflón!
Uploaded by fernantwo on 10 Feb 09, 6.49PM CST.
El río Tinto por su paso por Nerva. Gracias x todo muflón!
Uploaded by fernantwo on 10 Feb 09, 6.49PM CST.
untitled
nice colours and textures I think - it's always worth looking down....
Uploaded by chirgy on 10 Feb 09, 1.25PM CST.
Uploaded by chirgy on 10 Feb 09, 1.25PM CST.
Monday, February 9, 2009
Workflow Technique #065 Color Correction using a Gray Card
Workflow Technique #065
Color Correction using a Gray Card
by Brad Hinkel
Manage the Digital Workflow
I sometimes sound like I obsess about color balance; in many ways, color balance is one of the first steps to creating a great image; good balance makes the colors pop, makes the color contrasts stronger, and makes the image more pleasing. Color balance can be very challenging to get right; it can be hard to see what the color cast of a scene or image is, much less to know exactly how to balance it. Good color balance takes lots of experience to see and I am still improving my ‘vision’ of color both in the real world and on the screen.
In the real world, the lighting conditions are usually less than idea for color correction; outdoor or indoor lighting is seldom close to the photographic ideal color temperatures for ‘daylight’ or ‘tungsten’. This can be resolved fairly easily by capturing a photo of a gray card in the same lighting conditions and correcting to the gray.
The basic steps
Setup and shoot your first exposure normally; I typically just set my digital camera to use its auto white balance setting as this will not change between shoots. The auto white balance for most cameras does an ok job, but it only gets the color balance close and usually does not create a great color balance. If you are shooting hand held and are worried about small changes in the auto white balance, just set the white balance to its nearest manual setting (here I would use the ‘Shade’ white balance setting). If shooting film, I just shoot with daylight balanced film.
My Original Image showing the Color Cast of the Scene
(Download this image to follow these steps)
Next, place a gray card into the scene into the questionable light (this could be the overall light of the scene, or perhaps just the shadows). I suggest the official Kodak gray card, as these are designed to be neutrally balance in a wide range of lighting conditions. Make a second exposure. These two shots don’t need to be identical (ie. Shot on a tripod), but they do need to be as close to one another as practical. Read more about possible gray cards here.
The Same Scene with a Gray Card Added
(Download this image as well)
Process your images normally, just make sure that the original image and the gray card image are both processed identically.
In Photoshop, open the image with the gray card. Select the color sampler tool (it is hidden under the eyedropper tool); this tool places sample points onto the image that allow you to see the precise values for each point; click on the gray card with the color sampler tool, this places a sample point on the gray card, the color values for this point are shown in the info palette.
Notice that the R, G, & B values of the gray card are not equal; the card is not gray in this image.
A Color Sample Point on the Gray Card
To get the color balanced, we now need to adjust the color of the image so that the three color values for the gray card are returned to neutral. I typically pick the middle value for the three color points (RGB) and adjust the other values to match it. This produces a neutral gray without changing the density much.
To adjust the gray values, create a new Levels adjustment layer (called ‘correct gray card’). Within the levels adjustment layer, we can edit the midtone values (or the gamma) for the three individual channels to obtain a neutral value for the gray card. Once I have a neutral gray card, accept the Levels adjustment.
In this case, I adjusted the Red and Green channels to match the blue channel. The image now appears to have better color balance. I typically select the middle value (here: Blue 170) as the target value for the other two channels; this ensures that each channel is changed as little as possible.
Adjusting Levels to Get the Gray Card Gray Again
This should create a correctly color balanced image, but there are many times that we want the image color corrected, but wish to maintain some of the color cast of the ambient light. This helps make the image retain some of the environmental color. For example, we often wish to remove the Blue/Cyan color cast from shadows, but not remove it completely; otherwise the image might appear unrealistic. The easiest way to reduce the color correction is to reduce the opacity of the Levels adjustment layer; often a fairly small amount helps, perhaps reducing the opacity to 80% or 90%.
To finish, we just need to move the Levels adjustment layer that contains the correct color balance over to the image without the gray card. Open the image without the gray card in Photoshop, return to the gray card image, select the Levels adjustment layer(‘correct gray card’) and duplicated it use the Layer/Duplicate Layer. In the Duplicate Layer Dialog, chance the document to target the image without the gray card; this will duplicate the Levels adjustment layer onto the new image.
Copying the Adjustment Layer over to the Original Image
The Final Image
What about the Camera’s Custom White Balance
Many digital cameras include a custom white balance setting that does essentially the same adjustment as I do by shooting a gray card, so why not just use the cameras settings. If your camera does have this setting and you are comfortable with it, go ahead and keep using it. I still prefer to use shoot a gray card for a few reasons: First, the gray card works with any camera, film or digital. Second, if I don’t adjust the custom white balance, I don’t run the risk of shooting in a different light but forgetting to change the custom white balance; shooting with auto white balance gives me ok color balance most of the time. Third, shooting a gray card allows me to color correct for one part of the image with mixed lighting, for example, I can correct the shadows of an image by making an image with the gray card in the shadows and then correcting only the shadows in Photoshop. Finally, shooting with a gray card allows me to have the original image with the original color cast found in the real scene, the gray card allows me to correct for this color cast, but I have the option to only correct it most of the way towards neutral and retain some of the original color cast. For many images this retains the best overall look.
Advanced Technique (for Digital SLR Images)
I have been informed that the gamma correction used in the basic levels adjustment will product inaccurate color correction in the highlights for images captured with most digital SLR cameras. This is due to the non-linear response of the sensors in these cameras. The advantage to using the color correction using curves rather than levels is subtle but still noticeable.
The following steps use a more accurate curve adjustment instead of the levels gamma adjustment.
To adjust the gray values, create a new Curves adjustment layer (called ‘correct gray card’). Within the Curves adjustment layer, we can add a midtone adjustment point for two of the three individual channels to obtain a neutral value for the gray card. Select the first channel to edit, add a midtone adjustment point and move it up or down to match the value of the midtone for this channel to the target value.
Gamma Correction in Curves to Correct Midtones
To get a good overall color balance, the highlights will need to be shifted as well. Bring the highlight point down (or up/left) slightly so that the upper part of the curve is parallel to the center line of the curve; you may need to adjust the midtone adjustment slightly to keep the target value correct.
Highlight Correction in Curves
Change to the second channel that you wish to adjust and repeat. Once all of the channels have the same value at the target point then the gray card will be neutral. Hit OK to accept the Curves adjustment layer. Now the image appears to be more neutral overall.
(Thanks to Steve White at Microsoft for pointing out the problem with gamma corrections and digital cameras).
Color Correction using a Gray Card
by Brad Hinkel
Manage the Digital Workflow
I sometimes sound like I obsess about color balance; in many ways, color balance is one of the first steps to creating a great image; good balance makes the colors pop, makes the color contrasts stronger, and makes the image more pleasing. Color balance can be very challenging to get right; it can be hard to see what the color cast of a scene or image is, much less to know exactly how to balance it. Good color balance takes lots of experience to see and I am still improving my ‘vision’ of color both in the real world and on the screen.
In the real world, the lighting conditions are usually less than idea for color correction; outdoor or indoor lighting is seldom close to the photographic ideal color temperatures for ‘daylight’ or ‘tungsten’. This can be resolved fairly easily by capturing a photo of a gray card in the same lighting conditions and correcting to the gray.
The basic steps
Setup and shoot your first exposure normally; I typically just set my digital camera to use its auto white balance setting as this will not change between shoots. The auto white balance for most cameras does an ok job, but it only gets the color balance close and usually does not create a great color balance. If you are shooting hand held and are worried about small changes in the auto white balance, just set the white balance to its nearest manual setting (here I would use the ‘Shade’ white balance setting). If shooting film, I just shoot with daylight balanced film.
My Original Image showing the Color Cast of the Scene
(Download this image to follow these steps)
Next, place a gray card into the scene into the questionable light (this could be the overall light of the scene, or perhaps just the shadows). I suggest the official Kodak gray card, as these are designed to be neutrally balance in a wide range of lighting conditions. Make a second exposure. These two shots don’t need to be identical (ie. Shot on a tripod), but they do need to be as close to one another as practical. Read more about possible gray cards here.
The Same Scene with a Gray Card Added
(Download this image as well)
Process your images normally, just make sure that the original image and the gray card image are both processed identically.
In Photoshop, open the image with the gray card. Select the color sampler tool (it is hidden under the eyedropper tool); this tool places sample points onto the image that allow you to see the precise values for each point; click on the gray card with the color sampler tool, this places a sample point on the gray card, the color values for this point are shown in the info palette.
Notice that the R, G, & B values of the gray card are not equal; the card is not gray in this image.
A Color Sample Point on the Gray Card
To get the color balanced, we now need to adjust the color of the image so that the three color values for the gray card are returned to neutral. I typically pick the middle value for the three color points (RGB) and adjust the other values to match it. This produces a neutral gray without changing the density much.
To adjust the gray values, create a new Levels adjustment layer (called ‘correct gray card’). Within the levels adjustment layer, we can edit the midtone values (or the gamma) for the three individual channels to obtain a neutral value for the gray card. Once I have a neutral gray card, accept the Levels adjustment.
In this case, I adjusted the Red and Green channels to match the blue channel. The image now appears to have better color balance. I typically select the middle value (here: Blue 170) as the target value for the other two channels; this ensures that each channel is changed as little as possible.
Adjusting Levels to Get the Gray Card Gray Again
This should create a correctly color balanced image, but there are many times that we want the image color corrected, but wish to maintain some of the color cast of the ambient light. This helps make the image retain some of the environmental color. For example, we often wish to remove the Blue/Cyan color cast from shadows, but not remove it completely; otherwise the image might appear unrealistic. The easiest way to reduce the color correction is to reduce the opacity of the Levels adjustment layer; often a fairly small amount helps, perhaps reducing the opacity to 80% or 90%.
To finish, we just need to move the Levels adjustment layer that contains the correct color balance over to the image without the gray card. Open the image without the gray card in Photoshop, return to the gray card image, select the Levels adjustment layer(‘correct gray card’) and duplicated it use the Layer/Duplicate Layer. In the Duplicate Layer Dialog, chance the document to target the image without the gray card; this will duplicate the Levels adjustment layer onto the new image.
Copying the Adjustment Layer over to the Original Image
The Final Image
What about the Camera’s Custom White Balance
Many digital cameras include a custom white balance setting that does essentially the same adjustment as I do by shooting a gray card, so why not just use the cameras settings. If your camera does have this setting and you are comfortable with it, go ahead and keep using it. I still prefer to use shoot a gray card for a few reasons: First, the gray card works with any camera, film or digital. Second, if I don’t adjust the custom white balance, I don’t run the risk of shooting in a different light but forgetting to change the custom white balance; shooting with auto white balance gives me ok color balance most of the time. Third, shooting a gray card allows me to color correct for one part of the image with mixed lighting, for example, I can correct the shadows of an image by making an image with the gray card in the shadows and then correcting only the shadows in Photoshop. Finally, shooting with a gray card allows me to have the original image with the original color cast found in the real scene, the gray card allows me to correct for this color cast, but I have the option to only correct it most of the way towards neutral and retain some of the original color cast. For many images this retains the best overall look.
Advanced Technique (for Digital SLR Images)
I have been informed that the gamma correction used in the basic levels adjustment will product inaccurate color correction in the highlights for images captured with most digital SLR cameras. This is due to the non-linear response of the sensors in these cameras. The advantage to using the color correction using curves rather than levels is subtle but still noticeable.
The following steps use a more accurate curve adjustment instead of the levels gamma adjustment.
To adjust the gray values, create a new Curves adjustment layer (called ‘correct gray card’). Within the Curves adjustment layer, we can add a midtone adjustment point for two of the three individual channels to obtain a neutral value for the gray card. Select the first channel to edit, add a midtone adjustment point and move it up or down to match the value of the midtone for this channel to the target value.
Gamma Correction in Curves to Correct Midtones
To get a good overall color balance, the highlights will need to be shifted as well. Bring the highlight point down (or up/left) slightly so that the upper part of the curve is parallel to the center line of the curve; you may need to adjust the midtone adjustment slightly to keep the target value correct.
Highlight Correction in Curves
Change to the second channel that you wish to adjust and repeat. Once all of the channels have the same value at the target point then the gray card will be neutral. Hit OK to accept the Curves adjustment layer. Now the image appears to be more neutral overall.
(Thanks to Steve White at Microsoft for pointing out the problem with gamma corrections and digital cameras).
Sunday, February 1, 2009
Henry Rayburn
Henry Rayburn
BORN: Oct. 27, 1944, in Cleburne
DIED: Jan. 27, 2009, in San Antonio
PRECEDED BY: His parents, Jim Rayburne, former mayor of Alvarado, and Pauline Hanks Rayburne
SURVIVED BY: His siblings and their spouses: Claudine and David Marion and Michael and Pam Rayburne of Fort Worth; Paula Rayburn, Byron and Karen Rayburne, and Rhonda and John Forsythe of Alvarado; Debra Stroud of Mansfield; and Pat and Charles White of Tyler as well as 29 nieces and nephews; 18 great nieces and nephews, and one great-great niece
Sam Rayburn Contemplates The Vastness of the Universe
Sam Rayburn Contemplates The Vastness of the Universe
A statue of Sam Rayburn in the lobby of the Rayburn House Office Building -- one of three buildings where members of US Congress have their offices.
Rayburn, whom the building is named after, is regarded by many as one of the greatest Speakers of the House in U.S. History.
A statue of Sam Rayburn in the lobby of the Rayburn House Office Building -- one of three buildings where members of US Congress have their offices.
Rayburn, whom the building is named after, is regarded by many as one of the greatest Speakers of the House in U.S. History.
Henry Rayburn
Henry Rayburn could make art out of almost anything — spools of thread, a Fiesta gown, tarnished silverware, sofa pillows, mirrors, teddy bears and puzzle pieces. His mixtures of glitz and nostalgia were sweet and playful, referring to the city's history and old family stories.
He designed the "Dancing Letters" that seem to twist and shout across the fanciful façade of the Maury Maverick Jr. Library, which also features giant, playful abstract paintings on metal that suggest a child's view of flowers and foliage.
Collage artist, preservationist and community activist, Rayburn died Tuesday. He was 64.
"His passion was for his art and his friends," said Jim Nelson, a friend who teaches at the UT Health Science Center. "From my perspective, I thought he could turn anything in the world into a beautiful object. He collected all kinds of unusual objects. His home in King William looks like one of the old museums, the cabinet of curiosities — it's just filled with incredible things."
In 2006, Rayburn rounded up nine other San Antonio artist collectors for "Juxtapositions," which ranged from antique measuring devices to Barbie dolls, at the Alameda National Center for Latino Arts and Culture.
"I definitely think using found objects in a collage is a San Antonio thing," Rayburn said about the work he showed in the 2006 exhibit. "I take objects and alter them slightly, such as this 1972 Fiesta gown that I dropped on a mirror. This collection of colored light bulbs came from the O'Neil Ford estate sale. The spools of thread in a bon-bon jar are candy for the eyes."
He graduated from Alvarado High School in 1963 and then studied architecture at the University of Texas at Austin. After spending two years in Colombia with the Peace Corps, he worked in San Francisco and San Antonio as an architect. But he left architecture in 1985 to pursue his art full time.
He studied art at the Art Institute of San Antonio. With rendering, watercolor and drawing skills from his architectural training, he began to work in collage and then moved into three-dimensional assemblages made from found objects.
"Henry was a simple, gentle fellow with a good, adventurous eye for design," said Richard Conn, owner of the Nueva Street Gallery where Rayburn worked for 15 years. "Coming out of nowhere in 1985, he showed tremendous growth as an artist. He had a real impact on people locally, and probably would have become a much better-known artist nationally if he had had a few more years."
Rayburn showed in galleries in Texas and Colorado. He was included in several of the annual "Blue Star" surveys of local artists during Contemporary Art Month. For a special outdoor exhibit during "Blue Star 17," he placed stuffed animals in the windows of the old Frederick Building. Curator Terri Sultan of Houston's Blaffer Gallery selected Rayburn as the only sculptor included in "Blue Star 18."
His five large-scale assemblages in "Blue Star 19," curated by Lynn Herbert of Houston's Contemporary Art Museum, included "Quito," which paid tribute to a long-departed pet parrot. Rayburn chronicled his travels in a series of three "journals" protected by antique-looking Japanese paper umbrellas in "Blue Star 20" curated by George Neubert, former head of the San Antonio Museum of Art.
His last exhibit, featuring new work with puzzle pieces, was last November at the Koelsch Gallery in Houston.
Services: Funeral services will take place at 2 p.m. Saturday (Jan. 31) at the First Baptist Church in Alvarado, Texas. A memorial service in San Antonio is set for 6 p.m. Feb. 7 at SAY Si, 1518 S. Alamo St. Friends are invited to bring objects to add to an "offrenda"
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