resolution

Parameter defining the included resolution for the image processing and of the image

Lower Resolution Limit [RESMIN]

is a limit that is used to cutoff the low-resolution artifacts. When looking at a high-resolution 3D map, sometimes alpha helices are easier to identify when the low-resolution components are not included in the dataset. Usually, you can keep this value at "200.0" Angstroems.

Upper Resolution Limit [RESMAX]

is the resolution limit that should be applied during the image processing, in Angstroems. For example, you are processing a negative stain image, then usually you would want to limit the included resolution to "16.0" Angstroems, since there is little chance that any information beyond that resolution can be found in the image. Limiting the resolution to reasonable numbers allows better unbending because less noise is included during the localization of the CCMap's peaks. The data in the end are evaluated without any resolution limitation so limiting the resolution here does not mean that higher resolution data will not be available. However, if the reference did not contain reference details beyond the here specified resolution, then the unbending has a hard time following structural details at highest resolution. It is therefore recommended to set the resolution limitation to a value that is optimistic but not ridiculously high.

Merging resolution limit [merge_res_limit]

This switch allows you to determine if a global fixed resolution limit (specified in the 2dx_merge program) should be applied to all images during merging, or if every image should rather be merged with its own individually defined resolution limit.

Resolution of the merged dataset for reference [MergeResolution]

Specifies the resolution up to which the merged dataset can/should be used as reference for unbending of the images. For more information see also merging.

ALAT (Z-dimension of unit cell to reconstruct) [ALAT]

is the assumed vertical dimension of the 2D crystal in 3D space. A normal membrane protein crystal would have a vertical thickness of 100.0 Angstroems, so that a vertical slab dimension of "200.0" Angstroems should be enough to include the entire 3D volume.

Temperature Factor for Map Generation [tempfac]

can be used to increase the high-resolution details in the final map. A negative temperature factor of -100 Angstroem-2 for example enhances higher resolution components, using a quadratic profile, up to the RESMAX cutoff.