3 replies to this topic

[Moid]

Hello everyone

Below you will see two images, one a random pictureseque scene of the Lac D'Amour in Bruges in colour, the second my attempt at creating a gum bichromate render simulation in Nuke. Gum Bichromate is a very old photographic process that produces extremely soft. painterly, beautiful images from standard photos (it was fashionable in the very late 19th century / early 20th century and was used heavily by members of the Pictorialist Art Movement). I've always loved the appearance of these photos that are often more painting than photography and was procrastinating massively (as one does during the Summer) and thought hmmm I wonder if I can simulate that? So I'll put the images below and I'd welcome any opinions about areas of the image that do not look late 19th century because I've been staring at this one for far too long now...

Before anyone says anything, gum bichromate images often picked up a colour tint as a result of the developing process, and I've seen some beautiful blue ones and so added my own blur tint. Also I don't want to deliberately damage the photo to show tears and backing paper either.

original



my gum bichromate version

[Aldarion]

For one colour dichromate prints they used to brush unwanted shadows out at the end of the process with a soft brush, perhaps add some of that ?
I would perhaps try doing some lumakeys for the branches and use them as subtle masks for blurring, just to see what it looks like.

Looks quite gorgeous though, planning to do a moving version ?

[JustAnotherFool]

Now I have seen Gum pictures that have the same curves as yours, but as the contrast junkie I am I'd say push the white until it clips a little more for those smooth blown out whites. The dark side of the curve is perfect. Although in general it seems that the curves are wholly dependent on what kind of camera you're simulating so there really is no right or wrong.

This guy does some awesome gum bichromate developed photos with a pinhole camera: http://chriskeeney.c...le-photographer (Scroll down a little)

[Moid]

Thanks Mario, I hadn't considered actually putting some brushstrokes in, that is a thought... I did actually luma the branches out to blur them a little, I guess it's too subtle? Maybe aI'll try a stronger version - oh do you mean the foreground branches at top right or the trees in the distance? I did the trees in the distance, the foreground branches seemed to vanish with some blur on them and they ended up looking more like a render artefact... maybe I should try a slight directional blur instead...

Making it move - that is an idea even though it is strictly speaking a bit bizarre regarding the original process but I might try it - at present it flickers horribly (not in a good way, it looks really CG, something to do with the way I am abusing the film grain I think) I need to slow the film grain down... it needs projecting onto a surface and try again... maybe I'll choose an urban location so there isn't as many issues with movement of the environment.

Thanks for the suggestion Mike - this originally started as an attempt at platinotype simulation (which does have a really wide tonal range) but I thought it didn't look much different to using some careful curves (I'd used about 10 nodes) and I thought this isn't going anywhere, so let's push it to destruction and so I looked at some gum bichromate images and though, that looks fun! I will probably leave the contrast as it is, although it might be useful to keep it for some close up foreground elements (if there were any). And it's interesting for once not to maximise the contrast - the original photos do not have darker tones and when I added them it seemed to me that it no longer looked old... There are some lovely images in the link you posted - I still need to get the whole image to break up into grains more, I'm hoping the request that Chunky replied to elsewhere might allow me to have varying size grains across the image which is what I want (I think).