Professional Photography Program
DL 2 Laurel Breidon
Assignment 3
B/W Film Processed, Scanned and output A3 Ink Jet Print 25%
Due: Start of class, Thursday March 10. (Late assignments marked at 60 or 0%).
Purpose: To introduce students to B/W film, scanning technology and principals and
continue perfection of LR Editing and Printing skills.
Submit: Students will submit one A3 sized ink jet prints and one 36 frame roll of
properly exposed and developed negatives.
Method Expose and develop one roll ( 24 or 36 Exps.) of 35 mm film. (Or one roll, 12 exps.
120 film). Scan the resulting negatives. Output one high quality A3 ink jet print.
Please submit all test prints and print failures as well.
For the purposes of this assignment students must print in-house, at Dawson.
Place the print and negatives in an appropriately sized manila envelope. The envelope
should be identified with the teachers name, your name, the course name and the
assignment number on the outside front surface. One assignment per envelope.
The envelope should not be sealed. Please no padded envelopes
Grading: The images will be marked on technical competence; proper distribution of
tonal values, shadow detail, highlight detail, sharpness etc.
Please remember that the aesthetic content of the image is central to the assignment
and image impact will affect the final grade.
No boring pictures.
Thursday, February 24, 2011
Sunday, February 13, 2011
Soft Proofing in Lightroom-3/Photoshop
SoftProofing in Lightroom/PhotoShop
• Set Prefs in LR (Bit Depth, Colour Space, Resolution, File Format)
• Prophoto is the one because of increased gamut in Epson Ultrachrome
Inks
• Open File in PhotoShop (Command E)
• Duplicate Image >Image>Duplicate (as reference)
• Go to View>Proof Set-Up>Custom
• Find Appropriate Printer Profile
• Work through Dialog Box
• Preserve RGB Numbers (Off) What your file will look like if you print in
Color Workspace not Printing Profile.
• Black Point Compensation (On)
• Simulate Paper Color (On)
• Simulate Black Ink (On)
• Fix your file Image> saturation, curves etc,using copy as reference
• Back to Lightroom (Save) Look for file with Edit attached to title
• Print
• Set Prefs in LR (Bit Depth, Colour Space, Resolution, File Format)
• Prophoto is the one because of increased gamut in Epson Ultrachrome
Inks
• Open File in PhotoShop (Command E)
• Duplicate Image >Image>Duplicate (as reference)
• Go to View>Proof Set-Up>Custom
• Find Appropriate Printer Profile
• Work through Dialog Box
• Preserve RGB Numbers (Off) What your file will look like if you print in
Color Workspace not Printing Profile.
• Black Point Compensation (On)
• Simulate Paper Color (On)
• Simulate Black Ink (On)
• Fix your file Image> saturation, curves etc,using copy as reference
• Back to Lightroom (Save) Look for file with Edit attached to title
Sunday, February 6, 2011
CIE xyz and CIE LAB
Nearly all color management software today uses a device-independent space defined by the Commission International de l' éclairage (CIE) in 1931. This space aims to describe all colors visible to the human eye based upon the average response from a set of people with no vision problems (termed a "standard colorimetric ").The CIE space of visible color is expressed in several common forms: CIE xyz (1931), CIE LAB, and CIE L u'v' (1976). Each contains the same colors, however they differ in how they distribute color onto a two-dimensional space:
(All color spaces shown are 2D cross-sections at 50% Luminance)
CIE xyz is based on a direct graph of the signals from each of the three types of color sensors in the human eye. These are also referred to as the X, Y and Z tristimulus functions (that were created in 1931). However, this representation allocates too much area to the greens — confining most of the apparent color variation to a small area.
CIE L u'v' was created to correct for the CIE xyz distortion by distributing colors roughly proportional to their perceived color difference. A region that is twice as large in u'v' will therefore also appear to have twice the color diversity — making it far more useful for visualizing and comparing different color spaces.
CIE L*a*b* remaps the visible colors so that they extend equally on two axes — conveniently filling a square. Each axis in the LAB color space also represents an easily recognizable property of color, such as the red-green and blue-yellow shifts .These traits make LAB a useful color space for editing digital images, such as with Adobe Photoshop, Lightroom, etc.
(All color spaces shown are 2D cross-sections at 50% Luminance)
CIE xyz is based on a direct graph of the signals from each of the three types of color sensors in the human eye. These are also referred to as the X, Y and Z tristimulus functions (that were created in 1931). However, this representation allocates too much area to the greens — confining most of the apparent color variation to a small area.
CIE L u'v' was created to correct for the CIE xyz distortion by distributing colors roughly proportional to their perceived color difference. A region that is twice as large in u'v' will therefore also appear to have twice the color diversity — making it far more useful for visualizing and comparing different color spaces.
CIE L*a*b* remaps the visible colors so that they extend equally on two axes — conveniently filling a square. Each axis in the LAB color space also represents an easily recognizable property of color, such as the red-green and blue-yellow shifts .These traits make LAB a useful color space for editing digital images, such as with Adobe Photoshop, Lightroom, etc.
ICC
The International Color Consortium.
The ICC is a group which is made up of representatives from Adobe Apple HP and many others. This is why we hear the term ICC color profiles
It involves several key concepts color profiles, color spaces and the translation between color spaces.
The ICC is a group which is made up of representatives from Adobe Apple HP and many others. This is why we hear the term ICC color profiles
It involves several key concepts color profiles, color spaces and the translation between color spaces.
Perceptual and Relative Colormetric Intents
Perceptual and Relative Colorimetric Rendering Intents
Perceptual and relative colorimetric rendering are probably the most useful conversion types for digital photography. Each places a different priority on how they render colors within the gamut mismatch region. Relative Colorimetric maintains a near exact relationship between the in gamut colors, even if this clips out of gamut colors. In contrast perceptual rendering tries to also preserve some of the relationship between out of gamut colors, even if this results in inaccuracies for in gamut colors.
Perceptual maintains smooth color gradations throughout by compressing the entire tonal range, whereas relative colorimetric clips out of gamut colors.
Even though perceptual rendering compresses the entire gamut it does remap the central tones more precisely. The exact conversion depends on what the CMM is used for
Adobe ACE Microsoft ICM and Apple color sync are some of the most common
Absolute colorimetric Intent
Absolute is similar to relative colorimetric in that it preserves in gamut colors and clips those out of gamut, they differ in how each handles the white point, The white point is the location of the purest and lightest white in a color space. If we drew a line between the white point and the black point in a color space this would pass through the most neutral colors. The location of this lines changes between color spaces. Relative colorimetric skews the colors within the gamut so that the white point of one aligns with that of the other. While absolute colorimetric preserves colors exactly without regard to changing the white point. Absolute colorimetric preserves the white point while relative displaces the colors so that the old white point aligns with the new one. The exact preservation of colors may sound appealing, however relative colorimetric adjusts the white point for a reason. Without this adjustment absolute colorimetric results in unsightly color shifts and as such is rarely of interest to photographers.
The color shift results because the white point of the new color space usually needs to align with that of the light source or paper tint used. If one was printing to a color space for a paper with a bluish tint. Absolute colorimetric would ignore this tint change. Relative colorimetric would compensate to account for the fact that the whitest and lightest point has a tint of blue.
-Saturation rendering intent tries to preserve saturated colors, and is most useful when trying to retain color purity in computer graphics when converting into a larger color space. If the original RGB device contained pure (fully saturated) colors, then saturation intent ensures that those colors will remain saturated in the new color space — even if this causes the colors to become relatively more extreme.
Saturation intent is not desirable for photos because it does not attempt to maintain color realism. Maintaining color saturation may come at the expense of changes in hue and lightness, which is usually an unacceptable trade-off for photo reproduction. On the other hand, this is often acceptable for computer graphics such as pie charts.
Perceptual and relative colorimetric rendering are probably the most useful conversion types for digital photography. Each places a different priority on how they render colors within the gamut mismatch region. Relative Colorimetric maintains a near exact relationship between the in gamut colors, even if this clips out of gamut colors. In contrast perceptual rendering tries to also preserve some of the relationship between out of gamut colors, even if this results in inaccuracies for in gamut colors.
Perceptual maintains smooth color gradations throughout by compressing the entire tonal range, whereas relative colorimetric clips out of gamut colors.
Even though perceptual rendering compresses the entire gamut it does remap the central tones more precisely. The exact conversion depends on what the CMM is used for
Adobe ACE Microsoft ICM and Apple color sync are some of the most common
Absolute colorimetric Intent
Absolute is similar to relative colorimetric in that it preserves in gamut colors and clips those out of gamut, they differ in how each handles the white point, The white point is the location of the purest and lightest white in a color space. If we drew a line between the white point and the black point in a color space this would pass through the most neutral colors. The location of this lines changes between color spaces. Relative colorimetric skews the colors within the gamut so that the white point of one aligns with that of the other. While absolute colorimetric preserves colors exactly without regard to changing the white point. Absolute colorimetric preserves the white point while relative displaces the colors so that the old white point aligns with the new one. The exact preservation of colors may sound appealing, however relative colorimetric adjusts the white point for a reason. Without this adjustment absolute colorimetric results in unsightly color shifts and as such is rarely of interest to photographers.
The color shift results because the white point of the new color space usually needs to align with that of the light source or paper tint used. If one was printing to a color space for a paper with a bluish tint. Absolute colorimetric would ignore this tint change. Relative colorimetric would compensate to account for the fact that the whitest and lightest point has a tint of blue.
-Saturation rendering intent tries to preserve saturated colors, and is most useful when trying to retain color purity in computer graphics when converting into a larger color space. If the original RGB device contained pure (fully saturated) colors, then saturation intent ensures that those colors will remain saturated in the new color space — even if this causes the colors to become relatively more extreme.
Saturation intent is not desirable for photos because it does not attempt to maintain color realism. Maintaining color saturation may come at the expense of changes in hue and lightness, which is usually an unacceptable trade-off for photo reproduction. On the other hand, this is often acceptable for computer graphics such as pie charts.
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