tomopitch(1) General Commands Manual tomopitch(1) NAME tomopitch - Determines tomogram shift and angles from models of section SYNOPSIS tomopitch [options] DESCRIPTION Tomopitch analyes simple models of the boundaries of the section in slices from a tomogram and recommends how much to change tilt angles to make the section flat, how much to shift the tilt axis in Z to produce centered slices, and how thick to make the slices. It can also recom- mend how much X-axis tilt is needed to make the section flat in the orthogonal direction as well. It can also be used with a model drawn on a whole tomogram, possibly binned down. The typical use is with samples of the tomogram in separate files. For each sample of the tomogram, make a model file with two contours in it. Each contour should have two points, with the line between them lying along the top or bottom surface of the section. The points do not have to be entered in any particular order, and the lines do not need to be any particular length (the program will extend them in X, if necessary, to within 5% of each edge of the tomogram). As an alternative to making a separate model file for each sample, you can load all of the samples into 3dmod together and make a single model file, creating a pair of contours at each different time index. Make this model file be the sole entry to Tomopitch, and it will analyze each of the time indexes separately, the same as if they were in sepa- rate files. A third alternative is to make a model on an entire tomogram. Such a model can take two forms. It can consist of any number of pairs of horizontal lines, where each par is drawn predominantly in the X direc- tion along the top and bottom of the section. This can be done while viewing the YZ planes of the tomogram, just as in the samples of YZ slices. The lines can also be drawn while viewing the XY planes of the tomogram in the Zap window, or they can be drawn in the Slicer window with the angles adjusted to make a surface appear all at once in the window. These lines do not need to be parallel to the X axis, but try to draw the two lines of a pair at approximately the same location in Y. The program expects the separation in Y between the two lines of a pair to be less than 0.3 times the separation between successive pairs. The second form for a model on a whole tomogram consists of a pair of horizontal lines near the middle of the tomogram, and a pair of lines oriented vertically (predominantly in the Y direction) along the top and bottom of the tomogram. Only one pair of lines of each type is allowed. With this input, the program will construct two more pairs of horizontal lines by sliding the pair that were entered to the low Y and high Y ends of the vertical lines. Analysis then proceeds with the three pairs of horizontal lines. If you make a model on an entire tomogram, you need not enter a value for the spacing in Y. If the tomogram is binned down relative to the final tomogram, enter the binning factor as a scale factor to get val- ues appropriate for the final tomogram. The program analyzes each pair of horizontal lines separately. It determines what rotation is required to make the section be flat. It reports the upward shift needed to center the section in Y, and the slice thickness needed to contain the section. These values are derived and reported before and after the recommended rotation is applied. Thickness values include an additional amount that you spec- ify and are rounded up to integers suitable for taking 3D FFTs. After all pairs of lines are analyzed, the program makes the same analysis and report based on the data from all of the files. It then computes an X-axis tilt and reports thickness and rotation if that tilt is taken into account as well. OPTIONS Tomopitch uses the PIP package for input (see the manual page for pip) and can take input interactively for options that existed when it was converted, to maintain compatibility with old command files. The following options can be specified either as command line arguments (with the -) or one per line in a command file or parameter file (with- out the -). Options can be abbreviated to unique letters; the cur- rently valid abbreviations for short names are shown in parentheses. -model (-m) OR -ModelFile File name Model file with lines to analyze. If there are multiple model file entries, they should be in order that they will be consid- ered in the program. (Successive entries accumulate) -extra (-e) OR -ExtraThickness Floating point Additional pixels of thickness to add to both the top and the bottom of the tomogram, beyond the region described by the model lines. Enter values as unbinned pixels, i.e. pixels after the scaling factor has been applied. -spacing (-sp) OR -SpacingInY Floating point Spacing between tomogram samples (distance in Y in tilted views). If a non-zero number is entered, the program will com- pute the tilt around the X-axis that will make the tomogram be flat in its Z dimension. -scale (-sc) OR -ScaleFactor Floating point Amount by which to scale the Z shift and thickness recommended by the program. Use this entry if the model was drawn on binned-down samples or a whole binned-down tomogram but you intend to make an unbinned tomogram. The scale factor is the binning factor. -angle (-a) OR -AngleOffsetOld Floating point Angle offset in the alignment used to make the samples. If this entry is present, the program will output the original, added, and total offset. -zshift (-z) OR -ZShiftOld Floating point Z shift value in the alignment used to make the samples, in unbinned pixels. If this entry is present, the program will output the original, added, and total Z shift. -xtilt (-x) OR -XAxisTiltOld Floating point X axis tilt applied when the samples were made. If this entry is present, the program will output the original, added, and total X axis tilt. -noxtilt (-n) OR -NoXAxisTilt Do not solve for X axis tilt or changes in other values when X- axis tilt is compensated for. An incoming value of -xtilt will be ignored, but if positioning tomogram(s) were remade with a non-zero X-axis tilt, the reported values will still be appro- priate for such an X-tilted tomogram. Thus, it is best to have this option present on the first round of positioning, or to remake the tomogram(s) with X-axis tilt set to 0. -param (-p) OR -ParameterFile Parameter file Read parameter entries as keyword-value pairs from a parameter file. -help (-h) OR -usage Print help output -StandardInput Read parameter entries from standard input. INTERACTIVE INPUT If the program is started with no command line arguments, it reverts to interactive input with the following entries: Additional pixels of thickness to add to both the top and the bottom of the tomogram, beyond the region described by the model lines. Spacing between tomogram samples (the distance in Y in the tilt images.) If a non-zero number is entered, the program will compute the tilt around the X-axis that will make the tomogram be flat in its Z dimension. Number of model files to analyze For each file, then enter the name of the file. HISTORY Written by David Mastronarde, January 2000 5/20/01: Added analysis of single file with multiple time indexes 11/13/03: Converted to PIP, added ability to draw lines in whole tomogram BUGS Email bug reports to mast at colorado dot edu. IMOD 5.2.0 tomopitch(1)