DeepSpace
Filter |
Filter
Name |
Space
Hunter |
Compatibility |
Adobe
Photoshop 5.0 and later. |
Required
RGB working-space |
This filter
works correctly only in the AIM working-space (Trinitron,
D6500 and gamma 1.0)
that is the output space of the filter.
Incorrect working-space
gamma is indicated by a superimposed gray cross-bar in the preview
image.
|
Description |
Provides
gamma control, color temperature correction either by correlated color-temperature
slider or gray sampling using a probe, color-space conversion saturation
and hue adjustment. Colorimetry is absolute in CIE xyY. |
Installation |
Download
and copy all files from the zip archive into the /photoshop/plug-ins
directory. |
Setup
|
Open a higher
bit-depth image (or convert a 8-bit/channel image to the 15-bit
mode, then enter to the filter dialog and press Alt+g to
open the Define screen settings -dialog. Enter the system
gamma space that is the gamma value from the Adobe Gamma utility
(or from other system calibration utility) not the gamma value
from the RGB setup.
This one-time-only
step is needed in order to have the image in the preview box to
appear correctly.
|
Sliders |
Gma
(.01) |
File Gamma.
Used for linearization of the image. Adjust only the tonal range
with Gma. Especially look at the deep shadows, areas that appear
as pure black indicate too low gamma linearization, increase the
Gma value. Airy or thin or washed out apperance indigate too high
gamma linearization, decrease the Gma value. Slider value is 100x.
|
CCT
(K) |
Correlated
Color Temperature, in Kelvin from 2200K to 12000K. Used for balancing
color-cast due to illumination. In case the gray probe is active
this control is disabled.
If the image
is already edited (of unknown color-temperature) it may be much
better to use the probe.
If the image
is not already edited this control usually gives much more natural
apperance than the probe.
Note that the
output color temperature is fixed ( to D6500) so this control
appears to effect in reverse, in other words the CCT value of the
slider is the color temperature of the image before correction to
D6500.
Use PV Modes
4...7 to help in adjusting the gray balance.
|
Sat
(%) |
Adjust the
saturation, carefully, 50% increase is rather much.
This control
can totally damage the image if adjusted too heavily. Some images
can be saturated very much some only little, this also depends on
the amount of the white-point correction that is needed.
Use the PV
mode 3 to evaluate the clipping at highlights and if necessary use
the WP slider to give headroom for the saturation enhancement.
|
Hue° |
Adjust hue
in the range -60° ... 60°.
This control
should be regarded as the last resort, it takes the chromaticity
of the image out from the specified color-spaces. However for artistic
purposes it may be very good.
|
S
radius |
Gray
sampler radius. E.g. radius 5 is the average of 5x5 pixel area. |
PV
mode |
Preview mode.
There are 7 preview modes.
- Shows saturation
map. This can be used for gray balance evaluation.
- Shows clipping
at shadows. Shows the location of the pixels that will be clipped
to level 0. The intensity of those pixels shows the clipped amount.
- Show clipping
at highlights. Shows the location of the pixels that will be clipped
to maximum level. The intensity of those pixels shows the clipped
amount.
- Shows gray
areas of the image.
- Shows more
gray areas of the image.
- Shows even
more gray areas of the image.
- Shows still
more gray areas of the image.
The preview
modes 4...7 show the filtered result with areas that have high color
saturation masked with black. So, only the greyish image areas are
visible. Very useful for color balance.
Clipping display
in preview options 2 and 3 are color coded. White means that the
image information of the pixel is completely clipped. Red means
red channel is clipping, green means green channel is clipping blue
means blue channel is clipping, cyan means both the green and blue
channels are clipping, magenta means both the red and blue channels
are clipping and yellow means both the red and green channels are
clipping.
The preview
modes are active only when the PV mode check box is checked.
Use the preview
modes to evaluate and estimate the effect of the various operations.
|
WP
ev(.01) |
White-point
adjustment in ev. 100 means one ev or one f/stop. -100 means -1ev
or -1 f/stop.
Some image
enhancement operations will peak some of the color channels of some
pixels to the maximum level value. WP control is used to give headroom
for the operation by expanding the range. It can also contract the
range, use it when there is tail in the histogram.
Use carefully,
it will clip when when contracting and scaling up too much will
make the image to appear un-naturally.
Use the PV
mode 3 (show clipping at highlight) when adjusting the the WP control.
|
Sat
x5 |
Multiplies
the saturation amount by 5. This is special function, useful e.g.
for data mining behind a saturation mask. |
Check
Boxes |
PV
mode |
Enable/Disable
the Preview display.
When this option
is selected the preview mode is active and the selected preview
operation is applied over the filtered result.
|
Selection
Dropdown |
Choose
the input color-space of the image. The output space is always Trinitron.
E.g. Some scanners and digicams have the CIE RGB color-space. |
Color
Sampler |
The probe adjusts
the color temperature of the image. Drop the probe on a surface
that should appear as gray (but currently has a color cast). Using
the probe will disable the CCT slider.
Read the Filter
Formula Efficient Use -page about the issue when using the sampler.
Use PV Modes
4...7 to help in adjusting the gray balance.
|
Usage |
Useful as the
first step in editing images of unknown working space and generally
for hue, saturation and white-balance corrections.
- Adjust the
gamma for natural tonal range.
- Adjust CCT
for good gray balance. If it can not be found then drop the gray
probe on an image area that was gray in the real-life.
- Increase
the saturation if necessary.
- Step through
the dropdown entries, trying evaluate what entry gives the most
natural colors (this is it, space hunting).
- use the
Preview option 3 to evaluate if the corrections require headroom,
if it does use the WP slider
|
Author |
Timo
Autiokari. |
Homepage |
Accurate
Image Manipulation for Desktops |
Usage
Right |
Free. |
Distribution Right |
Distribution
is prohibited. |
Filter
Engine |
FilterFormula
v 1.13, by ATS/Graphics
(extended version for 16-bit images). |