Thanks for contacting us and for your question.
works with a Minimum
and a predefined step. You could mimic the behavior you would like to achieve by changing the step each time the user changes the value so that the next value is the next from your f stop values series
Another possibility would be to use the RadListPicker
control and pre-load all possible values that you have and let the user choose from them.
I hope this helps.
Do not hesitate to get back to us in case you have further questions or need assistance.
the Telerik team
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