I believe it is based on what you have showing in 3D when you open the dialgue box.
Each view will scale to be the same as the one that shows plan view.
So the less you can show in the plan view then the bigger all the views will be.
You can place a marquee but that will still zoom to the extent of whatever the marquee cuts trough.
So you are better off selecting in plan and then showing in 3D to get just what you want.
Unfortunately there is no zoom in or out - just making the dialogue box larger.
I think this is one of the reasons GS moved away from this in version 17 where you now have adjustable cutting planes (and lots of them - not just 3) in the actual 3D window.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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