This is site is a pre-alpha download node for an Excel Spreadsheet Implementing Shape-for-Shading (SFS) per Carlotto 1996. As the project is development progress, this node will be developed into a project homepage.
Under Tools, select Macro | Visual Basic Editor
In the Visual Basic Editor, select Tools | References
Select the checkboxes next to the applicable object libraries listed above.
| Slideshow | Audio | No. of slides | Audio length (mins) | Topics |
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| SfS theory simplified - Part 1 | Link | 32 (2.5Mb) | 46 (5.3Mb) |
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| Parts of the spreadsheet - Part 2 | Link | 52 (4.9Mb) | 60 (6.9Mb) |
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| Importing a user image - to the spreadsheet | Link | 45 (4.7Mb) | 38 (4.8Mb) |
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| Lambert lunar model and sensitivity analysis | No audio | 6 (23kb) | No audio | A short slideshow on (1) why the Lunar Lambert model breaks down after 30° of solar altitude and (2) the sensitivity of a computed DEM to accuracy of the measurement of the Sun's altitude at the lunar feature. |
| Error analysis | No audio | 3 (129kb) | No audio | A short slideshow demonstrating the new (ver 0.7) error analysis feature on Workflow Menu. |
When preparing an image for SFS analysis, use an 8-bit or 16-bit greyscale FITS file. An 8-bit FITS file allows for 255 pixel levels. Conversion of color to greyscale images converts color data to luminance values. AIP4WIN is a commonly used astronomical image processing package that allows for such conversions with an express option to not stretch or modify the original pixel values.
There are a variety of layouts that can be used when an imager converts a FITS greyscale image into a comma separated value text file containing pixel values. One layout, used by Evans 2006, is a series of "triples" - a list of pixels and pixel values consisting of a col, row and pixel value on one line. A 70 x 80 pixel image would contain 5,600 rows of "triples".
Another layout for image pixel values converted to text, used here by DEMCarlottoMethod.xls, is an NxM matrix. An 70 x 80 matrix of image pixel data contains the pixel values - 80 columns of values to a line in a text file of 70 lines.
There are two software packages that generate such NxM matrices in a csv text data files. The first is a governmental astronomical freeware package, distributed by NASA's High Energy Astrophysics Science Archive Research Center (HEASARC), called "FV" - short for "FITS Viewer." (URL Link: FV Homepage FV Download page). FV is a FITS file viewer and editor that runs under Windows, Unix and MacOS. Conversion of a FITS file to text data is self-explanatory and requires no special user tips. Once a FITS file is open, there is a menu option to view the image and a second option to view the image as a table of pixel values. Once in table viewing mode, there is an option to save the file as a csv text data file. The resulting csv data file can be directly opened by Excel and the result pasted into DEMCarlottoMethod.xls's data analysis worksheet "ImagePixelValueMap".
The second software package is the proprietary Meade AutoStar Imaging Processing package. When viewing an image in Meade AutoStar Image processing, if the entire image is selected by dragging the cursor from the upper left to the lower right-hand corner of a FITS file, an option dialogue pops up that allows the user to save an NxM matrix text file. Then the csv data file is moved into DEMCarlottoMethod.xls's data analysis worksheet "ImagePixelValueMap". by the process described above.
K. Fisher
