Common difficulties

Twice as many jobs as expected starting at the same time

It is likely that you have started two identical job-processing servers (JPS) on the same computer; this can cause unexpected behavior. If this is the case, ensure you are running only one processing server.

Orthorectified images appear distorted ("squished")

If your orthorectified images appear compressed and disproportionate, your cell width and height of your chip are probably reversed in your camera-calibration XML file. To fix this, switch the width and height values.

All images are rotated and do not align

If your images seem proportionate, but do not align along their edges, you may have chosen the wrong kappa-rotation units. With flight paths that run north-south or east-west, kappa values in degrees will be in increments of about 90 degrees. If they are in gradians, the values will be in increments of 100.

Images align along flight paths, but not between

Your principal point is incorrect. If you have rotated the kappa value in your EO file, you must also adjust the principal point in your camera-calibration file using the information in the following table.

Table 1. Principal points of camera calibration
Original PP	Kappa Rotation	Modified PP
PP_X = x_mm PP_Y = y_mm	0 deg clockwise	PP_X = x_mm PP_Y = y_mm
PP_X = x_mm PP_Y = y_mm	90 deg clockwise	PP_X = y_mm PP_Y = -x_mm
PP_X = x_mm PP_Y = y_mm	270 deg clockwise	PP_X = -y_mm PP_Y = x_mm
PP_X = x_mm PP_Y = y_mm	180 deg clockwise	PP_X = -x_mm PP_Y = -y_mm

Orthorectification log says digital elevation model (DEM) does not overlap data, but it does

If you are convinced that your DEM should overlap your input data, it is likely that you have a projection mismatch. Ensure all of your projection and coordinate information is correct, and then try running the process again. Try plotting your EO data over the DEM in CATALYST Professional Focus.

Orthorectification is taking a very long time

Output resolution plays a large role in file size and, consequently, in processing times. Incorrect output resolution is most often the cause of slow processing. If your resolution is too high, processing will likely be quite slow, as a lot of information is being written to disk. Ensure that your resolution matches the units that apply to the map projection; for example, the units of UTM are meter, and the units of most State Plane projections are feet. If your resolution is correct and you are still experiencing slow processing speeds, there may be issues with disk speed or network access.

Mosaic preview has dark or light spots and halos around edges

You have likely chosen an incorrect NoData value for the edges of your mosaic, and color balancing is using this data.

Mosaic is of poor quality ("patchy")

If your data was acquired at varying times of the year, it is likely that there are significant changes in vegetation color due to moisture and growth. Try running the Mosaic Preparation module without normalization or color balancing, and then compare this output to your previous result. This will provide a good indication of the quality of color balancing. There are times when image differences are too great to correct automatically. If it is clear that color balancing is still poor, ensure that your NoData value is correct during the mosaic-preparation stage.

Mosaic is of poor quality ("washed out")

This is most often caused by too aggressive an adaptive filter. Try running adaptive filtering with a higher percentage of image coverage; for best results, use a value above 40.

Mosaic is of poor quality ("stripping")

When "strips" occur along the flight lines, your georeferencing between images may be incorrect due to an incorrect value in the camera-calibration or EO file. Ensure that your images align, and, if you are still experiencing stripping, try running hot-spot normalization in addition to color balancing.