Yesterday, I received by post from a very nice fellow named James a new set of Brentano’s 45×107 glass positive slides, the box labeled simply “Verdun”. Being, in my mind, one of the most interesting battles of the Great War, I was excited to take a look at these 13 slides, even knowing that some of them were duplicates of slides I already had – or alternate angles of other Brentano’s slides from my collection. Plus, the box is just cool! For whatever reason, the slides from this manufacturer – the most common manufacturer of Great War Glass, who also sold to English-speaking markets as “Over There Group” – don’t tend to come in their original packaging. They’re usually loose, or stuffed into generic black boxes. So it’s cool to have one with the packaging intact.
The box contained 13 slides, all of which I scanned and viewed through my favorite 45×107 scope last night. The emulsions were all in very good condition save one – which is not usually the case with Brentano’s, since they used thin, easily-scuffable emulsions that would get scratches from cheap scopes. I considered just making a post on the entire set, but that wouldn’t leave me the enjoyment of posting more later – nor would it allow me to undertake a more interesting exploration: comparing some duplicate slides to see what can be learned about Brentano’s production process. As those of you who collect know, and those who don’t are about to learn, this manufacturer in particular can show a wide range of features in its slides, both 45×107 and 6×13 – different cropping, different labeling procedures, different emulsion colors, different contrast. Much of this is a result of the duplication processes used, which appear to be non-uniform and very much at the whim of whoever was compiling a set on a given day.
Making a contact print directly from a 6×13 negative, of course, is entirely unproblematic – the emulsions of the exposed and developed negative, and the unexposed positive, are placed against each other and illuminated; the positive is then developed. This produces as high a quality reproduction as possible at the time. Going from 6×13 down to 45×107 would require a bit more technical acumen, as the two halves of the 6×13 would have to be “shrunk” through a lens onto two halves of a smaller slide – and with a gap in the center. Positive duplication is more problematic still – there are two ways to go about it. A second-generation positive can be made by placing the emulsions against each other; the quality is degraded a little and the resultant image is mirrored, requiring either a third generation or backwards insertion into a scope. Alternately, diffused light through the first slide onto the emulsion will produce an un-mirrored duplicate, but at greater loss of quality.
I decided to compare four pairs of images from this set to see what can be discovered about the slides. Two are comparisons to earlier Brentano’s 45x107s from my collection; one a comparison between what I initially thought was an alternate angle on the Tranchée des Baïonnettes slide I had previously written about, and finally I tackle two copies of the same image which appeared in the “Verdun” set under consideration. Unusually for my posts, I’m going to post each pair of anaglyphs immediately following the stereo pairs, in order to allow comparison of the images in question.
1 – Bois-le-Prêtre
These two copies of the same scene from “The Priest’s Wood”, where a nasty bit of fighting occurred on the periphery of Verdun, are the closest to identical of anything I’ll be examining today. They’re both heavily-contrasted, but with a lot of detail still there; the cropping is nearly identical, and it seems like the main differentiating factor is a small light bleed in the margin of my earlier acquisition, and the writing in the margin of the new acquisition from the themed set. The earlier acquisition also appears a bit lighter in the right-hand pane. I put the anaglyphic merge point on the soldier at left:
And by far the most interesting thing about the anaglyph is the red artifact that appears in the lower-right of the frame – meaning that both of the slides came from a master (some unknown number of generations up) that had the same defect! Additionally, looking at the anaglyphs reveals that, while the older version does indeed have significant exposure differences between halves, the new acquisition suffers from the characteristic “center darkening” phenomenon, in which the edges nearer the margin in the center appear to be better exposed than the periphery. This phenomenon, and its inverse, are common in just about every antique stereographic process. At the end of the day, which of these is “better” is pretty ambiguous – it’s an aesthetic decision. I tend to prefer looking at the new copy a bit more in both anaglyph and scope.
2 – German prisoners carrying their wounded, Bois Bourru
Two things should be immediately apparent here: The new version is of a superior emulsion type and almost certainly an earlier generation – there is far more midtone detail, and the emulsion on the old version shows clumping characteristic of being a late-generation print. Secondly, the new version is a much tighter crop – the margins in this set are large, and while in the first image studied they were similar, in this one we’re clearly sacrificing image for space for the caption, which is overlaid into the emulsion of the copy negative for the new version (incidentally, the old version is more insulting towards the prisoners – it refers to them as boche instead of allemande). Which you prefer is a matter of choice of course, but let’s take a look at the anaglyphs, merged at the rubble pile at lower-right:
So each version has some issues – the new version, while offering creamier tonality, is cropped almost ridiculously close, while the better crop of the old version is hampered by the writing on the negative that made it. Additionally, this time it is the old version that suffers from “center darkening”. Once again it’s a toss up in anaglyph land, but through the viewer, the old version – which fills the scope nicely – wins out over the new.
3 – Tranchée des Baïonnettes
This one’s a bit unfair, as we’re comparing the weakest image from the “Verdun” set, and the only one in terrible condition, with a nice 6×13 slide from a different angle that I have previously blogged about. As it turns out, on closer examination, it’s not only from a different angle, but from an earlier date, but we’ll get to that – it wasn’t immediately obvious without a side-by-side comparison, and this being about the most photographed memorial in Verdun, it’s easy enough to make this mistake at first glance – you seen enough images of this memorial and they all sort of start to blend together. In any case, here are the images:
At first glance, two similar scenes with not-dissimilar composition. On closer look, very different images, with differences not only spatial, but temporal as well. In the new image (which was taken earlier), there is still more earth to be moved, there are bayonets sticking up somewhat obtrusively right near the camera, and the scene is quite dark. The image that was already in my collection has the obvious benefit of being much more details, having more than twice of the emulsion surface area of the former. Additionally, it was taken at a later date when more earth was moved, with a wreath lain atop the farthest wooden cross, and with much better lighting. It is clearly a superior image from the same manufacturer, and does not suffer from the numerous defects of the new “Verdun” slide. If you don’t believe me, check the anaglyphs:
Pretty clear-cut which one I’m going to favor for my viewing pleasure.
4 – Poste de secours
The first and final slides in the order I received the “Verdun” box in are duplicates – but one is clearly superior. Since I didn’t have a copy of this “emergency post” slide yet, I was glad to have one at all – and the second copy can always be bartered for someone else’s duplicate. Here are the slides:
It should be immediately obvious just on free-viewing that the final slide is of a significantly inferior quality – it lacks contrast, has clumped grain that removes detail, and I don’t need an anaglyph to tell me that there is center darkening here. But one interesting thing is that, even though these are obviously two images from a set of at least 155 Verdun slides (based on the random selection of numbers in this box), the numeration at least was consistent – the early generation slide and the late one both bear the number 44, albeit in different handwriting. I’ll conclude with the thought that it’s fascinating and fun to compare and consider the various versions of all of the Brentano’s slides floating around out there – different grain structures, different artifacts, different cropping. But in general, there are indeed better and worse versions of any given slide from the manufacturer. And finally, I’ll conclude with the anaglyphs for these, which should show that one is clearly the better of the pair: