6 ms·

Cultural Tattoos Invisible in Wet Collodion Prints (2018)

135 points by lelf 8y ago

benj111 7y ago
Is this an issue of contrast, and lack of sensitivity to it? I must say the effect is strange, it does make the people look darker and more 'foreign' (from a Europeans perspective) I wonder what effect photos like this had on perpetuating colonialism by making the natives appear less like themselves (the colonists).
- dylan604 7y ago
  The Wikipedia article on the process [0] talks about how the process is more sensitive to certain colors. [0] https://en.wikipedia.org/wiki/Collodion_process https://en.wikipedia.org/wiki/Collodion_process
- mkl 7y ago
  This kind of photography was not the only means of capturing pictures. Paintings for one captured all the details: https://www.google.com/search?tbm=isch&q=goldie+portraits https://www.google.com/search?tbm=isch&q=goldie+portraits I think the effect is a bit like what infrared photography does to freckles: https://petapixel.com/2015/09/28/this-is-what-infrared-photography-does-to-freckles/ https://petapixel.com/2015/09/28/this-is-what-infrared-photo...
- staticautomatic 7y ago
  It's because Wet Plate is typically orthochromatic.
  - galago 7y ago
    michrassena's comment has it right. 'orthochromatic' was a later term implying that the film represented the 'correct' version of the spectrum, because it was more sensitive to blue light. the term 'panchromatic' was adopted when black and white films eventually approximated visual sensitivity. the history of this spans decades, which is why it can be confusing. by the late 20th century, 'ortho' meant a monochromatic film or printing paper that was not sensitive to red light, hence it could be handled in a darkroom with a red safe-lite. however, the spectral sensitivity of even standard photo paper today might be greater than the earliest emulsions.
    - stan_rogers 7y ago
      "Orthochromatic" was a fix; it had extended green sensitivity compared to earlier processes/materials (which were usually referred to as "actinic" after ortho was introduced). Ortho was called ortho right from the beginning to distinguish it from what came before. The extended green sensitivity is what made it right. Or at least somewhat less wrong than things had been. If they'd found a way to create panchromatic plates/film before ortho as we know it happened, the name "orthochromatic" would have been given to that instead. So why did ortho rule the roost in the darkroom and in process photography when we had "actinic" papers around? (Obviously, panchromatic is out unless you like working in total darkness.) Incandescent lamps for exposure is a big part of the answer. You don't get a lot of blue light out of a glowing filament, and sunlight isn't quite as consistent and reliable as you might want it to be. (And arc lights aren't a lot of fun to work with or around.) Non-repro blue, a pale cyan that humans can easily distinguish but ortho film/paper can't, is most of the rest. Panchromatic can "see" non-repro blue by design, and "actinic" can see it because it's not blue enough to appear white if it's dark enough to see easily (in paste-up, etc.). Non-repro blue, ruby masks and relatively bright safelight made life... well, not exactly easy when compared to, say, a desktop publishing application, but it beat the heck out of constant squinting in the dark, wondering if that thing was really supposed to be there, or if it was a line at all.
      - staticautomatic 7y ago
        Developing film by inspection is a joy. I've developed a lot of ortho 4x5 under red safe light and love it even though I don't need to (my developer exhausts around the same time the film finishes developing so I don't actually need to inspect). I just do it for fun.
- michrassena 7y ago
  Early photographic processes were only sensitive to the blue end of the visible spectrum. It took many years after photography was developed for chemists to create dyes sensitive to red and green. Using only the blue channel from a color image is an easy shortcut to obtaining the look which is sometimes done to depict someone as rugged, aged, and weathered for artistic effect. Here's an article on simulating this look digitally, from the same publication. https://petapixel.com/2019/04/05/recreating-the-look-of-1850s-tintypes-in-digital-with-math-and-science/ https://petapixel.com/2019/04/05/recreating-the-look-of-1850...
  - staticautomatic 7y ago
    It's worth mentioning that contemporary photographers can make panchromatic wet plates, and also that orthochromatic film is available.
  - Zanni 7y ago
    Ah, interesting. I was wondering why they looked so much older, like 10-30 years older, to my eyes.
all2 7y ago
I saw faint outlines of tattoos in some of the "disappearing" photos. Could we use these as templates to recover tattoos in photos from the time-period the article mentions?
- deleted 7y ago
  [deleted]
- blotter_paper 7y ago
  I'm having trouble seeing this effect. I think I can make out a curved line on the left cheek of the man in this image[0], but I suspect that's actually due to the skin texture left from the tattooing process. Quoth TFA: > Tā moko is different from ordinary tattooing because chisels (called uhi are used to carve the skin and opposed to using needles and puncturing. As a result, the skin is grooved rather than smooth in the tattoo areas. [0]: https://petapixel.com/assets/uploads/2018/07/7.jpg https://petapixel.com/assets/uploads/2018/07/7.jpg
  - PostOnce 7y ago
    modern moko are almost all done with plain old needles, i think, and lack the pronounced scarring of the old methods. Super clear photo of the old result: https://scontent-yyz1-1.cdninstagram.com/vp/b80fdf49074ae5b49395361b2af846e8/5D76D72D/t51.2885-15/e35/40594732_392789677925072_1554535160492326912_n.jpg?_nc_ht=scontent-yyz1-1.cdninstagram.com https://scontent-yyz1-1.cdninstagram.com/vp/b80fdf49074ae5b4... (it appears to have been maybe sharpened in software?) edit to add: I think chisels are no longer used because 1] it's painful 2] not many people know how to do that anymore -- but they sure do look good, the old way. They used to use a bluer ink, made of caterpillar guts among other things? A painter named Charles Goldie did some great portraits showing that older pigment: https://i.pinimg.com/736x/c5/52/82/c55282ddab815e9e4d9d7f2d8d23f118--maori-people-unique-art.jpg https://i.pinimg.com/736x/c5/52/82/c55282ddab815e9e4d9d7f2d8... https://www.nzgeo.com/wp-content/uploads/1998/04/38_Goldie_13-1018x1300.jpg https://www.nzgeo.com/wp-content/uploads/1998/04/38_Goldie_1... https://s3.amazonaws.com/img.aasd.com.au/86317163.jpg https://s3.amazonaws.com/img.aasd.com.au/86317163.jpg https://images.internationalartcentre.co.nz/_auctions/2018/2018-08/2018-08-030-H.jpg https://images.internationalartcentre.co.nz/_auctions/2018/2... and many many more And some trivia, moko were occasionally used as signatures on old deeds and treaties, since moko identified the bearer and no two were the same: https://c8.alamy.com/comp/PM1Y2X/image-from-page-41-of-moko-or-maori-tattooing-with-illustrations-etc-PM1Y2X.jpg https://c8.alamy.com/comp/PM1Y2X/image-from-page-41-of-moko-...
LoSboccacc 7y ago
what a cancerous web page https://i.imgur.com/dRb8WQT.png https://i.imgur.com/dRb8WQT.png e: wow for a community that loves to talk about dark patterns you really seem to suck it up and drop all such considerations when it suits you
- olliej 7y ago
  50/50 people assuming you're complaining about the content buried underneath 20 banner ads, 50 overlays, 900 popups, and probably some malware. Although I guess most people are on desktop with ad blockers. Are there any actual good ones for iOS? I remember support the use case was going to bankrupt the entire industry a few years ago, so surely they must exist? I'm still not convinced any of the "new" ad formats (replacing popup/under with overlays :( ) actually improve con version rates, or whether people are accidentally clicking on the ads while trying to make the accursed overlays go away.
dang 7y ago
Url changed from https://petapixel.com/2018/07/09/wet-plate-photography-makes-tattoos-disappear/ https://petapixel.com/2018/07/09/wet-plate-photography-makes..., which points to this.
anotheryou 7y ago
I missed the part where it says why/how....
- Sir_Vival 7y ago
  The wet plate collodion process is only sensitive to blue/UV light. Those tattoos must fall elsewhere in the spectrum. As an aside, I've just started doing them myself and it's clear why there's been a resurgence. Scans don't really do them justice, and the aforementioned sensitivity makes freckles/other features really stand out. It's also really hard, and takes a good 5-10 minutes per shot.
- jml7c5 7y ago
  Take a look at Fig. 1 (page three) in this PDF: https://www.osapublishing.org/DirectPDFAccess/9295D3CA-C8BD-E5BA-0DBAC4920EEDA3BD_333549/ao-54-35-10559.pdf?da=1&id=333549&seq=0&mobile=no https://www.osapublishing.org/DirectPDFAccess/9295D3CA-C8BD-... ("Human skin detection in the visible and near infrared"). The photographic process used is only sensitive to blue/near-UV light. People with dark skin absorb lots of blue/near-UV light. This is why their skin looks darker under this process than it actually is. The tattoos also absorb blue/near-UV light, but the (apparently extra-dark) skin masks the difference, as the contrast ratio between skin covered/not covered with a tattoo is lowered.
Tepix 7y ago
Could you do the same thing with a digital filter?

135 points by lelf 8y ago

Is this an issue of contrast, and lack of sensitivity to it? I must say the effect is strange, it does make the people look darker and more 'foreign' (from a Europeans perspective) I wonder what effect photos like this had on perpetuating colonialism by making the natives appear less like themselves (the colonists).

dylan604 7y ago
The Wikipedia article on the process [0] talks about how the process is more sensitive to certain colors. [0] https://en.wikipedia.org/wiki/Collodion_process https://en.wikipedia.org/wiki/Collodion_process
mkl 7y ago
This kind of photography was not the only means of capturing pictures. Paintings for one captured all the details: https://www.google.com/search?tbm=isch&q=goldie+portraits https://www.google.com/search?tbm=isch&q=goldie+portraits I think the effect is a bit like what infrared photography does to freckles: https://petapixel.com/2015/09/28/this-is-what-infrared-photography-does-to-freckles/ https://petapixel.com/2015/09/28/this-is-what-infrared-photo...
staticautomatic 7y ago
It's because Wet Plate is typically orthochromatic.
- galago 7y ago
  michrassena's comment has it right. 'orthochromatic' was a later term implying that the film represented the 'correct' version of the spectrum, because it was more sensitive to blue light. the term 'panchromatic' was adopted when black and white films eventually approximated visual sensitivity. the history of this spans decades, which is why it can be confusing. by the late 20th century, 'ortho' meant a monochromatic film or printing paper that was not sensitive to red light, hence it could be handled in a darkroom with a red safe-lite. however, the spectral sensitivity of even standard photo paper today might be greater than the earliest emulsions.
  - stan_rogers 7y ago
    "Orthochromatic" was a fix; it had extended green sensitivity compared to earlier processes/materials (which were usually referred to as "actinic" after ortho was introduced). Ortho was called ortho right from the beginning to distinguish it from what came before. The extended green sensitivity is what made it right. Or at least somewhat less wrong than things had been. If they'd found a way to create panchromatic plates/film before ortho as we know it happened, the name "orthochromatic" would have been given to that instead. So why did ortho rule the roost in the darkroom and in process photography when we had "actinic" papers around? (Obviously, panchromatic is out unless you like working in total darkness.) Incandescent lamps for exposure is a big part of the answer. You don't get a lot of blue light out of a glowing filament, and sunlight isn't quite as consistent and reliable as you might want it to be. (And arc lights aren't a lot of fun to work with or around.) Non-repro blue, a pale cyan that humans can easily distinguish but ortho film/paper can't, is most of the rest. Panchromatic can "see" non-repro blue by design, and "actinic" can see it because it's not blue enough to appear white if it's dark enough to see easily (in paste-up, etc.). Non-repro blue, ruby masks and relatively bright safelight made life... well, not exactly easy when compared to, say, a desktop publishing application, but it beat the heck out of constant squinting in the dark, wondering if that thing was really supposed to be there, or if it was a line at all.
    - staticautomatic 7y ago
      Developing film by inspection is a joy. I've developed a lot of ortho 4x5 under red safe light and love it even though I don't need to (my developer exhausts around the same time the film finishes developing so I don't actually need to inspect). I just do it for fun.
michrassena 7y ago
Early photographic processes were only sensitive to the blue end of the visible spectrum. It took many years after photography was developed for chemists to create dyes sensitive to red and green. Using only the blue channel from a color image is an easy shortcut to obtaining the look which is sometimes done to depict someone as rugged, aged, and weathered for artistic effect. Here's an article on simulating this look digitally, from the same publication. https://petapixel.com/2019/04/05/recreating-the-look-of-1850s-tintypes-in-digital-with-math-and-science/ https://petapixel.com/2019/04/05/recreating-the-look-of-1850...
- staticautomatic 7y ago
  It's worth mentioning that contemporary photographers can make panchromatic wet plates, and also that orthochromatic film is available.
- Zanni 7y ago
  Ah, interesting. I was wondering why they looked so much older, like 10-30 years older, to my eyes.

all2 7y ago

I saw faint outlines of tattoos in some of the "disappearing" photos. Could we use these as templates to recover tattoos in photos from the time-period the article mentions?

deleted 7y ago
[deleted]
blotter_paper 7y ago
I'm having trouble seeing this effect. I think I can make out a curved line on the left cheek of the man in this image[0], but I suspect that's actually due to the skin texture left from the tattooing process. Quoth TFA: > Tā moko is different from ordinary tattooing because chisels (called uhi are used to carve the skin and opposed to using needles and puncturing. As a result, the skin is grooved rather than smooth in the tattoo areas. [0]: https://petapixel.com/assets/uploads/2018/07/7.jpg https://petapixel.com/assets/uploads/2018/07/7.jpg
- PostOnce 7y ago
  modern moko are almost all done with plain old needles, i think, and lack the pronounced scarring of the old methods. Super clear photo of the old result: https://scontent-yyz1-1.cdninstagram.com/vp/b80fdf49074ae5b49395361b2af846e8/5D76D72D/t51.2885-15/e35/40594732_392789677925072_1554535160492326912_n.jpg?_nc_ht=scontent-yyz1-1.cdninstagram.com https://scontent-yyz1-1.cdninstagram.com/vp/b80fdf49074ae5b4... (it appears to have been maybe sharpened in software?) edit to add: I think chisels are no longer used because 1] it's painful 2] not many people know how to do that anymore -- but they sure do look good, the old way. They used to use a bluer ink, made of caterpillar guts among other things? A painter named Charles Goldie did some great portraits showing that older pigment: https://i.pinimg.com/736x/c5/52/82/c55282ddab815e9e4d9d7f2d8d23f118--maori-people-unique-art.jpg https://i.pinimg.com/736x/c5/52/82/c55282ddab815e9e4d9d7f2d8... https://www.nzgeo.com/wp-content/uploads/1998/04/38_Goldie_13-1018x1300.jpg https://www.nzgeo.com/wp-content/uploads/1998/04/38_Goldie_1... https://s3.amazonaws.com/img.aasd.com.au/86317163.jpg https://s3.amazonaws.com/img.aasd.com.au/86317163.jpg https://images.internationalartcentre.co.nz/_auctions/2018/2018-08/2018-08-030-H.jpg https://images.internationalartcentre.co.nz/_auctions/2018/2... and many many more And some trivia, moko were occasionally used as signatures on old deeds and treaties, since moko identified the bearer and no two were the same: https://c8.alamy.com/comp/PM1Y2X/image-from-page-41-of-moko-or-maori-tattooing-with-illustrations-etc-PM1Y2X.jpg https://c8.alamy.com/comp/PM1Y2X/image-from-page-41-of-moko-...

LoSboccacc 7y ago

what a cancerous web page https://i.imgur.com/dRb8WQT.png https://i.imgur.com/dRb8WQT.png e: wow for a community that loves to talk about dark patterns you really seem to suck it up and drop all such considerations when it suits you

olliej 7y ago
50/50 people assuming you're complaining about the content buried underneath 20 banner ads, 50 overlays, 900 popups, and probably some malware. Although I guess most people are on desktop with ad blockers. Are there any actual good ones for iOS? I remember support the use case was going to bankrupt the entire industry a few years ago, so surely they must exist? I'm still not convinced any of the "new" ad formats (replacing popup/under with overlays :( ) actually improve con version rates, or whether people are accidentally clicking on the ads while trying to make the accursed overlays go away.

dang 7y ago

Url changed from https://petapixel.com/2018/07/09/wet-plate-photography-makes-tattoos-disappear/ https://petapixel.com/2018/07/09/wet-plate-photography-makes..., which points to this.

anotheryou 7y ago

I missed the part where it says why/how....

Sir_Vival 7y ago
The wet plate collodion process is only sensitive to blue/UV light. Those tattoos must fall elsewhere in the spectrum. As an aside, I've just started doing them myself and it's clear why there's been a resurgence. Scans don't really do them justice, and the aforementioned sensitivity makes freckles/other features really stand out. It's also really hard, and takes a good 5-10 minutes per shot.
jml7c5 7y ago
Take a look at Fig. 1 (page three) in this PDF: https://www.osapublishing.org/DirectPDFAccess/9295D3CA-C8BD-E5BA-0DBAC4920EEDA3BD_333549/ao-54-35-10559.pdf?da=1&id=333549&seq=0&mobile=no https://www.osapublishing.org/DirectPDFAccess/9295D3CA-C8BD-... ("Human skin detection in the visible and near infrared"). The photographic process used is only sensitive to blue/near-UV light. People with dark skin absorb lots of blue/near-UV light. This is why their skin looks darker under this process than it actually is. The tattoos also absorb blue/near-UV light, but the (apparently extra-dark) skin masks the difference, as the contrast ratio between skin covered/not covered with a tattoo is lowered.

Tepix 7y ago

Could you do the same thing with a digital filter?