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Only Black

JMRead said:
Hello David,

That's a great portrait enhanced by your technique, I can see how it would work but I bet the code to make it do so is very complex, fair play to you for sorting it out.

Cheers - J
Click to expand...

Its a tool that's within a Machine Vision Environment, a bit like a tool within Photoshop. The environment is actually free to download (a licence key is required to get it to talk to the outside world, ie have a camera or digital I/O connected). If anyone wants a go, then I'm happy to point in the right direction, and send a script to them with instructions that runs the analysis that I did.

A little more explanation, A Local Adaptive Threshold, places a grid over the image, and then in each cell it performs a Mean Threshold. This effectively applies a threshold at a mean value of the grey pixel values within that cell. The threshold value then depends on the contents of the cell.

This tool allows me to adjust the grid size (in pixels) and alter the threshold around the mean, ie I can set it to be 2 grey values above the mean for instance.

With very small parameter changes you can alter the result quite dramatically. One is a grid sizer of 10x10 the other 50x50

Xngzf13.jpg


jB05ApI.jpg
 
Is there some Photoshop or Gimp or other digital process that gives a solarisation effect? As in the brief 1930s fad of "solarising" the negative (e.g. Man Ray)
 
Hello David,

I can see that your process does work, may I ask if it's possible to continually go back to the original to make parts lighter or darker and then re-apply the process. Perhaps to lead the eye into the image or give some depth to it.

Hello Paul,

I love Man Ray's pic of Coco Chanel worra portrait! Thanks for reminding me I just had to get the book to look at it again :)

There is a solarisation filter in Ps
And a little tutorial here on how to use it;
http://adobe-photoshoptricks.blogspot.com/2011/02/using-photoshops-solarize-filter.html

Cheers both - J
 
JMRead said:
Hello David, I can see that your process does work, may I ask if it's possible to continually go back to the original to make parts lighter or darker and then re-apply the process. Perhaps to lead the eye into the image or give some depth to it.
Click to expand...

Any editing would be best done in Lightroom or similar, and then the process applied. If I set Lightroom to export to the same filename, then I can set my Machine Vision Tool to get the stored Lightroom Image and Reprocess, on my machine, pressing the go button and getting the resultant image takes less than 100mS. Its really very fast!

It would be quite complicated to lighten/darken areas within the Machine Vision tool, as its set up to process multiple images (think inspecting parts in a factory) as opposed to providing an interactive graphics editor.
 
Hello David,

This is one from a few years ago, the original was pancake-ish, my attempts to lead the eye are rather obvious but do work, I would use more finesse now.

49862856012_15b462dfd6_c.jpg


Stick at it I'm sure you'll find a way round it.

Cheers - J
 
JMRead said:
Hello David,

This is one from a few years ago, the original was pancake-ish, my attempts to lead the eye are rather obvious but do work, I would use more finesse now.

Stick at it I'm sure you'll find a way round it.

Cheers - J
Click to expand...

Surely the 'best' depth in a image is the way that it was taken in the first place, trying to manipulate the image to create a sense of depth is not something that I would normally undertake (and is probably beyond my artistic skills)

1eLf4FP.jpg
 
Hello David,

Your subject says it all that's very well done indeed and and excellent example of your technique. I take your point, we arrive at our images from differing points of view. Those for whom the the camera is an instrument of record and therefore scientific. And those for whom the camera is just a starting point, Julia Margaret Cameron being one of the first to do so.

The dichotomy was first realised formally in the UK by The Linked Ring. It was a photographic society created in the 1890's by Henry Robinson to propose and defend that photography was just as much an art as it was a science, motivated to propelling photography further into the fine art world. It continues today with Salon photography worldwide.

In the USA 20 or so years later Alfred Steiglitz started the Photo Secession with the same ethos as the LR. He went further though and published Camera Work a quarterly magazine, known for its beautiful photogravures reproducing the fine photographs of the Photo Secession members.

This dichotomy still pervades photography today the finest examples can be seen here

https://www.instagram.com/
and
https://www.artlimited.net/selections/bestof/

And the twain shall never meet.
Good thing too in my opinion.

Cheers - J
 
Last edited:
Hello all,

This one began as a experiment to see how much black I could introduce and still have some detail.

49885610378_f7033dd9f5_z.jpg


Starting with the concrete bottom of an old street lamp with the huge nut, a ventilation grille with the holes cut out, some old brake discs, a poster, a window with the glass cut out and my good friend in her Zentai.

Cheers - J
 
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