We discuss the properties of the Seyfert 1.5 galaxy LB 1727 , also known as 1H 0419-577 , from X-ray observations obtained by ASCA and ROSAT along with optical observations from earlier epochs .
The source flux was F _ { 2 - 10 } \simeq 10 ^ { -11 } { erg cm ^ { -2 } s ^ { -1 } } during the ASCA observations which were carried out 1996 Jul – Aug , and we find only modest ( \lesssim 20 % ) variations in the flux in this band , within or between these observations .
In contrast , a daily monitoring campaign over 1996 Jun – Sept by the ROSAT HRI instrument reveals the soft X-ray ( 0.1-2 keV ) flux to have increased by a factor \simeq 3 .
Significant variations were also observed down to timescales of \sim 40 ks .

We find the 2 – 10 keV continuum can be parameterized as a power-law with a photon index \Gamma \sim 1.45 - 1.68 across \sim 0.7 – 11 keV in the rest-frame .
We also report the first detection of iron K \alpha line emission in this source .
Simultaneous ASCA and ROSAT data show the X-ray spectrum to steepen sharply at a rest-energy \sim 0.75 keV , the spectrum below this energy can be parameterized as a power-law of slope \Gamma \sim 3.6 .
The X-ray emission appears to be unattenuated and we find that ionized gas alone can not produce such a sharp spectral break .
Even allowing the presence of such gas , the simultaneous ASCA and HRI data demonstrate that the underlying continuum is required to steepen below \sim 0.75 keV .
Thus LB 1727 is one of the few Seyferts for which we can rule out the possibility that the presence of a warm absorber is solely responsible for the spectral steepening in the soft X-ray regime .

Consideration of the overall spectral-energy-distribution for this source indicates the presence of a pronounced XUV-bump visible in optical , ultraviolet and soft X-ray data .
The source appears relatively weak in infrared emission and so if dust exists in the source , it is not excited by the nuclear radiation .