When the nodes are put in a group, their properties and pins can easily be added as input and output to the Groups they belong to and thus manipulated from outer node graphs. Let's continue on the Node Grouping tutorial. Check that MASTERGAMMASHARPEN group has two nodes inside

Select the SHARPEN node, go to SHARPEN property group and, see that it has a SHARPNESS property.

Click on the red circle icon next to SHARPNESS property to transform it to SHARPNESS pin on SHARPEN node.

Now, this property is added to SHARPEN node as below.

Adding Group Input Pin

After adding the SHARPNESS pin, we should be able to control this property from the outside of the MASTERGAMMASHARPEN group. Right click on the node graph inside this group and go to Create > Group > GroupInputPin

The Input pin is added as a GROUPINPUTPIN node and also as a pin to the group node to be edited outside the group.

GROUPINPUTPIN node's DATA TYPE property is Boolean by default. As SHARPNESS property is Float, click on GROUPINPUTPIN and choose Float as DATA TYPE .

Connect the INPUT pin of GROUPINPUTPIN to the SHARPEN node's SHARPNESS pin.

Changing the Value of a Group Input Pin

Go to Color Correction Group and see that MASTERGAMMASHARPEN group has a GROUPINPUTPIN pin.

Add a CONSTANT FLOAT by going to FLOAT.

After adding CONSTANT FLOAT node, change the value of FLOAT property as follows:

And see that the SHARPNESS property of SHARPEN node inside the MASTERGAMMASHARPEN group has also changed.

And the change takes place in the output image at the same time.