\begin{table}%t9
\caption{Physical properties and conditions of the interstellar medium in the lines-of-sight
toward the SMC~targets \mbox{\object{AzV 456}} and \mbox{\object{AzV 18}} (this work), 
the LMC~target \object{Sk-69~223} \citep{2006AetA...447..991C} and the Galactic 
targets \object{HD~62542}, \object{HD~144217} ($\sigma$-type) and \object{HD~149757} ($\zeta$-type).
UV~lines are indicated by (uv) and the weak and strong doublet lines by~(w) and~(s), respectively.}
\label{tb:comparison}
%\centering
\small
\begin{tabular}{lrrrrrrr}\hline\hline
        		      &       & \multicolumn{2}{c}{SMC} 	  &\multicolumn{1}{c}{LMC} & \multicolumn{3}{c}{MW} \\
\cline{3-4}\cline{6-8}
        		      &       & Wing		& Bar 	  	  & 30 Doradus	       & no bump	   & $\sigma$	       & $\zeta$   \\
Parameter	              & Unit  & \object{AzV 456}& \mbox{\object{AzV 18}} &\object{Sk-69 223}  & \object{HD 62542} & \object{HD 144217}& \object{HD 149757} \\\hline
 \Ebv\  		      & mag   & 0.27		& 0.17 	          &  0.2	       & 0.35	           & 0.2	       & 0.3       \\
$R_{\rm V}$			      &       & 2.2	      	& 2.9		  &  3.6 or 4.1        & 2.90		   & 4.0	       & 3.1	   \\
$A_{\rm V}$			      & mag   & 0.6	      	& 0.5		  &  0.8(0.2)	       & 1.02		   & 0.8	       & 0.9	   \\ 
5780 DIB            & m\AA\ per \Ebv\ & 256	     	& 135   	  &  725	       & 151		   & 800	       & 220	   \\
5797 DIB	    & m\AA\ per \Ebv\ & 133	      	& 47	  	  &  140	       & 24		   & 110	       & 90	   \\
6613 DIB	    & m\AA\ per \Ebv\ & 181	      	& $<$41  	  &  100	       & --		   & 200	       & 143	   \\
5780/5797		      &       & 1.9	      	& 2.9		  &  5.2 	       & 6.2		   & 7.3  	       & 2.4	   \\
log $N$(\ion{Na}{i})	  & cm$^{-2}$ & 12.8	      	& 12.6		  &  12.59	       & --		   &  12.94	       & 13.85     \\ 
			      &       & 13.6  (uv)    	& 		  &		       &		   &		       &	   \\
log $N$(\ion{K}{i})	  & cm$^{-2}$ & 12.6w (uv)    	& 11.76w  	  &  11.03	       & 11.90  	   &  11.19	       & 11.85     \\ 
			      &       & 12.7s (uv)    	& 11.36s  	  &		       &		   &		       &	   \\
log $N$(\ion{H}{i})	  & cm$^{-2}$ & 21.3	      	& 21.95		  &  21.46	       & 20.93  	   & 21.10	       & 20.73     \\
log $N$(\ion{Ca}{ii})       & cm$^{-2}$ & 12.3	      	& 13.1		  &  12.68	       & --		   &  11.73	       & 11.76     \\
\\ 
$N$(\ion{Na}{i})/$N$(\ion{Ca}{ii})&       & 2.5		& 0.5 	          &  0.9	       & -- 	           & 16.2	       & 123       \\
$N$(\ion{H}{i})/$A_{\rm V}$ 
         & 10$^{21}$ cm$^{-2}$/mag  & 2.6	      	& 18.4	      	  &  3.6	       & 0.8	           & 1.6	       & 0.6       \\  
$f(H_2)$		      &	      & 0.525		& 0.045	      	  & ?		       & 0.603	           & 0.05	       & 0.32      \\
log $N$(H$_{\rm tot}$)	  & cm$^{-2}$ & 21.75		& 21.95	      	  & 		       &		   & 21.13	       & 21.15     \\     
$N$(H$_{\rm tot}$)/$A_{\rm V}$  
         & 10$^{21}$ cm$^{-2}$/mag & 9.36	        & 17.95	          & 		       &		   & 1.69	       &  1.57     \\     
5780 / $Z$       & ($Z$ = $A_{\rm V}$/\ion{H}{i})& 179		& $<$442 	  &  522	       &  42	           & 256	       &  40       \\
5797 / $Z$       & ($Z$ = $A_{\rm V}$/\ion{H}{i})& 94		& $\leq$74 	  &  101	       &  7	           & 35		       &  16       \\
\hline
\end{tabular}
\end{table}