===== Resolution =====

If by some reason horizontal or vertical scale of the image is misrepresented, you are able to correct it. Use menu command [[view|View]] -> **Resolution** to do it. It is availiable if a surface image, curve, section, or histogram is active.

If you use **Resolution...** command to work with a surface image without any distances or sections plotted, the following dialog box will appear:

{{:en:processing:scale_1.jpg|}}

You can specify new vertical and horizontal units using **Units** fields. The maximum height difference on the surface may be corrected in the **Size Z** field.

Let us show in more details what is meant by **Bit size** field. In Femtoscan RAW-data files (*.spm) Z values are kept as short integers (short int = 2 bytes = 16 bits). Embeaded coefficients are used to convert this integers into real height values. If you open a file of a different format, containing height or some other information (intensity, for example) in different state, Femtoscan will transform it to the standart two-bytes format automaticaly. The height corresponding to one bit may be corrected in **Bit size** field.

Image sizes in //XY// plane may be changed in **Size X** and **Size Y** fields. If an option **Constant proportions** is selected, then X-Y proportions will be constant, otherwise you will be able to change them independently. If an option  **Apply to all images in the document** is selected, then the same scale will be set for all subimages, otherwise all changes will affect an active image only.

Other fields in the dialog box become availiable when a segment is plotted on the image, or when the command **Resolution...** is run for section, curve or histogram.

A typical use of **Resolution...** function is the scaling of images obtained by electron microscopy. They are usually written in *.tif format and contain a measuring scale: 

{{:processing:sbs.jpg|}}

When you [[..:file:открыть|Open]] a TEM image in Femtoscan its color shows the intensity in RGB units, and its //X-Y// scale is usually misrepresented. 
Select the scale bar (or any other known distance) with the [[линейка|linear]] tool, call the menu function **Resolution...** and set the correct values in **Distance** and **Units** fields (100 nm in our example):

{{:en:processing:resize.jpg|}}

After this operation it will be possible to measure distances in //XY// plane correctly.

The same dialog window will appear if you call **Resolution...** function for a [[сечения|section]] or for a [[гистограмма|histogram]]. In this case the field **Height** shows the height difference between vertical marks on the section profile or on the histogram. Similarly the **Distance** field shows the distance between vertical marks in //XY// plane, and **Dx** and **Dy** fields show //X// and //Y// proections of this distance.

If you want to change //XY// scale only (or vertical scale only), leave label **Z** (or **XY**) unmarked to avoid the automatic change of resolution in the second direction.