SetDirectory["C:\\drorbn\\AcademicPensieve\\Projects\\BBS"];
srcdir="C:\\drorbn\\BBS\\shots\\"

fnames=FileNames["17-1750-*", srcdir]

Rasterize[shot=Import[fnames[[8]]]]

BBImprove[shot_] := Module[{diag, s1,s2},
diag=Norm[ImageDimensions[shot]];
s1=ColorConvert[shot, "Grayscale"];
s2=ImageAdjust[ ImageApply[Max[#1-#2,0]&, {s1, Blur[s1, 0.01diag]}] ] // ColorNegate;
ImageAdjust[s2, 0.05]
];
BBImprove[shot] // Rasterize

origs=Import /@ fnames;
imps=BBImprove /@ origs;

ImageAssemble[Transpose[{origs, imps}]] // Rasterize

Length[fnames]

300{8./3, 10.5/9}

ImageDimensions[origs[[1]]]

Min[((ImageDimensions[origs[[1]]])/({600.`,450.`}))]

ImageRescale[img_, {w_,h_}] := ImageCrop[
ImageResize[img, Scaled[Min[{w,h}/ImageDimensions[img]]]],
{w,h}, Padding -> White
];
ImageRescale[imps[[1]], {600,450}] // Rasterize

Rasterize[ContactSheet=ImageAssemble[Partition[ImageRescale[#, {800,350}]& /@ imps, 3]]]

Export["ContactSheet.png", ContactSheet]