Block 7 - Clean V0

need to fix links to coverage, overlaps, and Zmaps.

Description

This block is used to complete all of the stages but it does not follow a set of steps. Instead, to complete Block 7, you need to assure that the DTM has achieved certain states. To achieve these states, you may need to run additional iterations, return to earlier Blocks, or make other adjustments. Errors and problems in the data will determine the steps and processes you need to follow.

Assumptions

Didn't include any material here yet. Do we need this section on this block?

Standard Process of States

The following table lists the states that a DTM goes through on its way to being perfected for a specific resolution. Each state criterion defines the quality of processing necessary to complete that state. The state description gives general guidance for achieving the state. However, it does not include all the steps that you may need to take to achieve the criterion. You may need to do many steps multiple times (such as building and loading an updated shape model). Because these steps can affect other states, you may then need to do more work to meet those criteria again.

State	Criterion	Description
Tiled	The DTM has undergone the basic stages of Lat/Lon Tiling (Block 6A) or Bigmap Tiling (Block 6B).	This state does not require any additional processing, just the batch mode.
Correlated	All the landmarks indicate a correlation score above 0.0000.	When you run find_nofitP, none of the landmarks throw the "*" error.
Imaged	There are at least 5 images for every landmark.	Five images are needed to have a robust DTM that accounts for error. If there are not 5, then 4 or 3 are acceptable; however, the number of images can never be less than 3.
Fitted	There are no maplets with more than 10 "no fit errors".	No Fit errors are thrown when overlaps is unable to match two maplets that should overlap. This error indicates that there are too many differences between the two maplets for SPC to find common ground. It is common for a few maplets to be missing one or two of their connections with other maplets. However, no maplet may have more than 10 no fit errors.
Geometry	You have run the program geometry with option 2 to update the spacecraft position and camera vector.	You should also iterate at least once after you run geometry. Do we need to explain a bit more here? Or is it just a stipulation to do geometry and then iterate??
Residualed	All errors thrown by residuals and marked by ">>" have been corrected.	Typically, you will run geometry with option 2 before running residuals. The standard input for this level is: `5 5xGSD GSD` . These inputs refer to: 5 image (or maplet) pixels (how close they are), 5 times the ground sample distance (the resolution of the maplets), and the ground sample distance. However, you may choose looser values to get a smaller list first. I still need help here to get this clear.
Re-tiled	Any holes in the DTM have been filled in.	For the global scale, use coverage and look for where the missing maplets are. You can also use ZMaps if it's available. For the local scale, build a bigmap and look for regions where the maplets were deleted. You can then build the missing ones by hand, or you can run the Bigmap Tiling (Block 6B) procedure.
Sigma'ed	A DTM created by densify or bigmap has sigma values showing all peaks reduced to < 2xGSD and the average is <GSD of the smallest maplet.	These values are shown in SIGMAS.TXT. Will those values make more sense if we write them out in words, as on residualed?

Advanced States

In some instances, you need to assure that the DTM achieves these additional, advanced state.

State	Criterion	Description
Re-imaged	You have added images to get as many as possible, doing the processing by hand as needed.	Adding more images reduces the amount of error in the model, so adding more images will make the model better. Do we want to add something about how to know when to stop??
Image geometry	You have completed an evaluation of all images such that each one has at least 4 landmarks defined to set the spacecraft position/pointing.	we need some description here. Maybe what I'd use to do the evaluation? how I could get at least 4?
Re-Residualed	You have used tighter limits for anything that throws an error.	Typically, you do this using these inputs: `2 2xGSD GSD` . This sets the image pixels to 2, and uses 2 times the ground sample distance (resolution of the maplets).

(Compiled by EP)

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