Lens Corrector PRO - v1.2,  (c) 2007 Richard Rosenman Advertising & Design. Release date: 07/11/04, Updated 09/05/07.



INSTALLATION:

Simply unzip "lenscorrectorpro.zip" and copy "lenscorrectorpro.8bf" to your "\Photoshop\Plug-Ins\" folder, or whichever plugin folder your host program uses. Load your program, open an image, go to the plugins menu and select the plugin.



INSTALLATION FOR REGISTERED USERS:

If you have registered your copy of Lens Corrector PRO, simply place the license file you have received via email into THE SAME FOLDER AS YOUR "lenscorrectorpro.8bf" FILE. This is very important as placing the license file in a different folder than the one it currently resides in will not switch your copy of Lens Corrector PRO to REGISTERED mode. As an example, if you followed the steps outlined in the above INSTALLATION section, you would also place the license file into the "\Photoshop\Plug-Ins\" folder.



REGISTRATION:

If you would like to register Lens Corrector PRO, please visit http://www.richardrosenman.com



LICENSING:

You may freely download the plugin and try it as much as you want, whenever you want, wherever you want, by whomever you want, while in DEMO mode. Once registered, ONE (1) Lens Corrector PRO license entitles ANY user to UNLIMITED use of the software, for an INDEFINITE period of time, on ONE (1) workstation ONLY. Currently, there is no floating license option. If you wish to use Lens Corrector PRO on multiple workstations such as in a studio environment, multiple licenses are required for EACH node.



LENS CORRECTOR PRO 1.0 FEATURE SET:


•Improved, faster lens correction algorithms.

•Ability to specify axis center for lens correction and all advanced image processing controls.

•User selectable crosshair colors and icons for clearer visual representations.

•Ability to specify the axis center in the preview window with the mouse, as well as through sliders.

•User selectable "Out of Range" color for marking and easily identifying invalid pixels.

•Multiplier for extreme lens correction distortions.

•"Scale to Window" feature intelligently fits lens corrected images to window size in order to minimize scale loss.

•Horizontal and Vertical precision image scaling.

•Horizontal and Vertical precision image skewing (shearing).

•Horizontal and Vertical precision image perspective adjustment.

•Horizontal and Vertical precision image curved tapering.

•Horizontal and Vertical precision image shifting.

•Precision image rotation.

•Horizontal and Vertical image flipping.

•Rendering statistics for preview redraws and estimated final renderings.

•Grid display for clear and precise lens correction visualization.

•Ability to custom define grid, as well as overlay over source image for even more precise lens correction visualization. 

•Ability to overlay grid lines only, cells only, both or none.

•"Conform to Fisheye" transformation algorithm with multiplier for extreme fisheye distortions.

•Horizontal and Vertical polar correction for polar pinching compensation.

•Ability to output individual color channels.

•Sub-pixel filtering (Nearest Neighbor, Bisquare, Bicosine, Bilinear, Bicubic) for clean, sharp and precise renders.

•Presets for various common camera lenses and their correction settings.



DESCRIPTION:


This filter corrects camera lens distortion. 


Whenever media is recorded with today's conventional cameras, lens distortion (to some degree) is unavoidable. The amount of distortion can depend on various factors, particularly the type of camera lens used. Lens distortion can be classified into two categories - "Barrel" distortion (similar to the exterior curves of a sphere) and "Pincushion" distortion (similar to the interior curves of a sphere). By using appropriate algorithms, these distortions can be minimized, eliminated and if desired, even reversed. Lens Corrector PRO takes camera lens distortion correction to a professional level, adding numerous image processing tools and algorithms for facilitating the removal of such distortion.


Correction Parameters
---------------------


These are the main controls you'll be using when correcting for lens distortion. Generally, you will not need to change the center axis or the multiplier, but in extreme cases, they can be of great help in reducing off-axis lens distortion.


Horizontal: Controls the horizontal amount of correction. (Use the multiplier for higher values).

Vertical: Controls the vertical amount of correction. (Use the multiplier for higher values). (NOTE: At default, the vertical is locked to the horizontal for proportional distortion correction. If you wish to set different horizontal and vertical amounts, simply deselect the "Vert = Horiz" button).

H. Center: Controls (in percentage) the horizontal center of the correction axis. (-100 is the left edge of the image, +100 is the right edge of the image).

V. Center: Controls (in percentage) the vertical center of the correction axis. (-100 is the top edge of the image, +100 is the bottom edge of the image).

Crosshair (dropdown menu): Specifies the display type of the axis crosshair. This is helpful when you wish to see the center axis more clearly, or not see it at all.

Color A: Specifies the color of the crosshair while in image preview mode. You may wish to change the crosshair color depending on what color your image is, in order to see it better. Defaults to green.

Color B: Specifies the color of the crosshair while in grid preview mode. Defaults to Blue.

Set: Selecting this button and RIGHT-CLICKING in the preview window will specify a new correction axis center. The mouse will change to a crosshair which reminds you that you are in axis selection mode. Although you can keep working while in this mode, remember to turn off the button once you have selected your new axis point.

Locks (Vert = Horiz): This will lock the vertical correction to the horizontal for proportional correction.

Out of range col: This will color any "Out of Range" pixels the specified "Out of Range Color". "Out of Range" pixels are those which, due to distortion, have been pulled in from off-screen. They are therefore invalid pixels and they can remain the color of the outer edge of the image from where they came from (button deselected), or they can be colored with the "Out of range" color (button selected).

Out of Range Color: This specifies the 'Out of Range' color.

Reset: Resets all 'Correction Parameter' controls to default.

Multiplier: This is a multiplier for the correction controls. (Please note that high values can severely distort your image.)


Advanced Parameters
-------------------


This section contains all the controls for advanced image fine tuning. You may find that correcting for lens distortion will (in most cases) scale your image to some degree. This is normal, and is due to the correction algorithms. With these controls, you can compensate for such scaling, as well as fine tune your image and even correct for additional distortions not necessarily caused by lens distortion. Finally, it is important to understand that all of the following controls work based upon the axis center. Therefore, adjusting the axis center will provide you with unlimited flexibility for these controls.


Scale to Window: This will attempt to fit the corrected image to the window size. By deselecting this button, you can see what the conventional correction algorithm does to the image scale. This feature will compensate for this scaling and refits your image to the window. 

V. Scale = H. Scale: This locks the V.Scale to H. Scale for proportional scaling.

Reset: Resets all 'Advanced Parameter' controls to default.

H. Scale: This controls the horizontal scaling of the image.

V. Scale: This controls the vertical scaling of the image. (NOTE: At default, the vertical is locked to the horizontal for proportional scaling. If you wish to set different horizontal and vertical scale amounts, simply deselect the "V. Scale = H. Scale" button).

H. Skew: This controls the horizontal skew (shear) of the image. This is useful for straightening out angled lines.

V. Skew: This controls the vertical skew (shear) of the image. This is useful for straightening out angled lines.

H. Persp: This controls the horizontal perspective of the image. This is useful for straightening out lines which tend to disappear towards a perspective point. 

V. Persp: This controls the vertical perspective of the image. This is useful for straightening out lines which tend to disappear towards a perspective point. 

H. Taper: This controls the horizontal tapering of the image. In case the above feature isn't enough, taper adds to the perspective flexibility by producing a tapered distortion with a non-linear inner curve.

V. Taper: This controls the vertical tapering of the image. In case the above feature isn't enough, taper adds to the perspective flexibility by producing a tapered distortion with a non-linear inner curve.

H. Shift: This controls (in percentage) the horizontal shift of the image. (-100 is the left edge of the image, +100 is the right edge of the image).

V. Shift: This controls (in percentage) the vertical shift of the image. (-100 is the top edge of the image, +100 is the bottom edge of the image).

Rotation: This controls the (clockwise) rotation of the image.

Flip Horizontal: This flips the image horizontally.

Flip Vertical: This flips the image vertically.


Statistics
----------


This is where your rendering statistics are displayed.


Preview: Prints the total rendering time elapsed for generating the preview image.

Full Image: Prints the (estimated) total rendering time required for generating the full size image.


Grid Parameters
---------------


The grid is one of the most important and useful features of Lens Corrector PRO. Because it is often difficult to see EXACTLY what your correction is doing to the image, enabling the grid will replace the preview with a custom defined grid with the same lens correction applied to it. It is important to know that the grid color is based on the "Out of Range" color so if you wish to change it from the default black, simply change the "Out of Range" color.


Display: Displays a grid instead of the image for more accurate correction visualization.

Cells: Specifies the numbers of cells (rows and columns) of the grid.

Overlay: Specifies (in percentage) the transparency of the grid over the image. This is useful when you want to see both the grid and image distortion together. In these cases, you may want to change the grid color from black to something brighter, depending on your image.

Uncorrected: Enabling this button will draw the grid without correction distortion. This is particularly useful for comparing your distorted images to straight vertical and horizontal lines.

Lines: Disabling this button will restrict the grid lines from being drawn.

Cells: Disabling this button will restrict the grid cells from being drawn.

Reset: Resets all 'Grid Parameter' controls to default.


Distortion Parameters
---------------------


These are additional distortion parameters for conforming an image into a fisheye transformation, as well as correcting polar pinching.


Conform to Fisheye: This will conform your image into a fisheye transformation.

Multiplier: This is a multiplier for the fisheye transformation. (Please note that high values can severely distort your image.)

Reset: Resets all 'Distortion Parameter' controls to default.

H. Polar Correction: This corrects for horizontal polar pinching.

V. Polar Correction: This corrects for vertical polar pinching.


Output Parameters
-----------------


This is where you specify your output parameters, as well as filtering and presets.


Output R, G, B: This specifies which color channels to output.

Filtering: Specifies what type of pixel interpolation to use. (Nearest Neighbor being fastest, Bicubic being best.) (For more info about this, please see "WORKFLOW TIPS" below.)

Presets: Specifies preset configurations for various camera lenses. (More to come in the future.)


Interface Properties
--------------------


These are general interface properties - that is, properties that affect your workflow.


Realtime (Pushbutton): Applies all effects (in realtime) on 'mouse drag' instead of on 'mouse release'. (This relates specifically to slider controllers.)

LOAD/SAVE: Load and Save settings. (.INI files)

OK/CANCEL: Apply or cancel the filter respectively.

Help:  Displays this help.

Reset: Resets all controllers to default settings.



WORKFLOW TIPS:

Lens Corrector PRO has been optimized for quality. As a result, it is important to understand the basic functioning of the software in order to know how to get the most out of it. 

The single most important setting to understand is filtering in the "Output Parameters" section (It's not labeled as such, but it is the drop-down menu which specifies "Bicubic" as default). Filtering defines what type of interpolation to use for any and all pixel transformation routines (distortion, scaling, rotation, etc.). To understand this better, try the following test. Set the filtering to 'Nearest Neighbor' and turn on the grid. Now apply some lens correction to it. Notice how jagged and pixelated the grid lines appear. Now switch your filtering back to 'Bicubic'. Notice how much cleaner the grid lines become. 

Lens Corrector PRO ships with 'Bicubic' filtering on by default. This type of filtering provides the best quality output, but at a moderate speed sacrifice. By switching to 'Nearest Neighbor', you can gain a substantial speed increase, but at a moderate quality sacrifice. It is therefore recommended that one use 'Nearest Neighbor' filtering for working, and switching to 'Bicubic' for final output.

Should you require additional speed and/or faster previews, try unselecting the realtime pushbutton. This will now update the preview window when you release the mouse button, instead of during the slider adjustment. In addition, zooming down a level in the preview window will add dramatic speed increases.

Working in passes is another helpful suggestion for correcting your images. The reason for this is because sometimes you may want to apply lens distortion correction to an image with one particular axis center point as well as use an advanced control with a different axis center point. In a case such as this, it is recommended to first apply the lens correction distortion to the image, then run Lens Corrector PRO again, reset the controls, and apply the advanced controls with the new axis center. This process can also be run in reverse order, depending on your image.

Working with selections can be extremely helpful when isolations specific areas of the image that need to be corrected. When doing so, set a selection feather so that the distorted selection edges blend seamless with the unselected parts of the image.

Fisheye distortions, as well as any extreme distortions, are especially difficult to correct due to the massive amount of distortion in the image. While it IS possible to correct such an image to some degree with Lens Corrector PRO, it can be an extensive task.



MINIMUM SYSTEM REQUIREMENTS:

Lens Corrector PRO will run on any PC capable of running Adobe Photoshop v4.0 or higher, or most applications compatible with Adobe's plugin specifications.

Lens Corrector PRO will NOT run on Macintosh systems. This is unfortunately a compiler limitation, not a developer decision. 

Lens Corrector PRO has been specifically developed for use with high-resolution displays. Therefore a minimum display resolution of 800x600 is required. A minimum display resolution of 1024 x 768 x 24 bit color is recommended.

Lens Corrector PRO works exclusively on RGB images. If you see the plugin grayed out in your plugins menu, you are probably not in RGB mode. 

Lens Corrector PRO works exclusively on 24 bit images (8 bits per channel). 48 bit (16 bits per channel) support is intended to be built into future updates. 

Lens Corrector PRO can run with any amount of memory, so long as the host application such as Adobe Photoshop is capable of running. However, a minimum memory capacity of 256 MB is recommended.

If at any time there is any doubt regarding Lens Corrector PRO's compatibility or functioning, simply try the demo version. If it works, so will the registered version.



KNOWN BUGS:

NONE.



FIXES:

1.1 - Fixed bug when applying filter resulting in a 200% speed increase.
1.2 - New GUI design.
1.2 - Windows Vista Compatibility.


FEEDBACK:

If you love, hate or absolutely don't give a damn about Lens Corrector PRO, please let me know at richard@richardrosenman.com



LENS CORRECTOR PRO HOMEPAGE:

http://www.richardrosenman.com



HOMEPAGE:

http://www.richardrosenman.com
