DSO5202BM: Unclear situation with setting of triggers

Oleg10011001

For example, the Rise Time parameter for this oscilloscope is 1.75 ns, so this oscilloscope is supposed to work with rectangular signals having a rise time of 8.75 ns. In these conditions, I do not quite understand why in the Slope trigger settings you can set a minimum value of 20 ns, and not for example 8-9 ns? In my 20ns it's very bad for an oscilloscope having a bandwidth of 200MHz and capable of normally reproducing a meander waveform with a frequency of 4MHz, having a rise time of about 4 ns ... 5 ns. Just to be able to feel the difference, I will point out that the Rigol DS1054Z oscilloscope, which has a bandwidth of only 50MHz, that is, which is initially designed to work with much lower frequency signals, the Slope trigger allows catching pulses having an edge rise time of 8 ns.