Camera Obscura » Lightroom

Turn photos into pencil drawings using Photoshop

Fabiano Busdraghi — Mon, 24 Mar 2008 20:34:59 +0000

Photoshop can turn a pics into a pencil or pen drawing.

It’s been a long time since I first tried to convert pictures into drawings, or more precisely, since I first tried to define a procedure that allows the simulation of a charcoal, pencil, blood drawing from a picture.

The majority of the online tutorials use automatic Photoshop filters, that I personally consider awful, both artistic, stylization and border identification ones. Images always seem a little bit artificial, the artistic technique they refer in reality are really different, you always notice it’s a filtered picture and not a real drawing and all of those images are extremely similar to each others. It is recommended to work with your own two hands, more than entrust an automatic system.

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The noise in digital zone plate photography

Fabiano Busdraghi — Sun, 10 Feb 2008 22:23:59 +0000

Zone plate A3 inkjet print, 2008. In order to properly appreciate the grain of the image it is necessary to see the print, because the reduced resolution necessary for web publication creates a false perception of the image.

The photographs obtained using a zone plate in place of an objective, like pinhole photos, undergo significant digital noise and have a distinct character in comparison to that present on normal photographs obtained with an objective.

A zone plate is definitely more luminous than a pinhole, but remains anyway much less luminous than a traditional objective; therefore you often use the high sensitivity of the camera and/or lengthy exposure times. The images obtained are also very soft not only in terms of detail, but also contrast. Often therefore you apply levels and contrast curves in Photoshop in order to give energy to the photograph, while simultaneously amplifying the digital noise present in the image.

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Anti color fringing to eliminate the residual chromatic noise

Fabiano Busdraghi — Fri, 01 Feb 2008 19:11:07 +0000

In some zones of the image, mostly in sharpen edges or where the noise is more intense, Noise Ninja leaves behind some chromatic noise.

Talking with Claudio Muzzetto about the article Local techniques of sharpening and noise reduction, we noticed the possibility of another passage that completely eliminates every kind of chromatic noise. The technique is used to reduce the color fringing, (colored halos between lights and shadows, generally due to chromatic aberrations), but can be successfully used to filter the chromatic noise. Once again, I suggest to download the images and observe them 100% zoom to notice the real effects obtained with the described technique.

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Local sharpening techniques and noise reduction

Fabiano Busdraghi — Sun, 13 Jan 2008 07:55:59 +0000

Original image, with exposition and contrast correction but no intervention of sharpening and noise reduction.

Concerning analogical photography, once fixed the negative enlarger factor, the detail of a print is principally determined by a good shooting technique (absence of micro blur, correct focusing, correct depth of field and so on) and the resolving power of the shooting objective and the one on the enlarger. The image grain is determined by the film choice, exposition and development. Moreover the development allows controlling the acutance of the image. Furthermore, during the print phase, it is possible to modify both the detail and the picture grain, for example using contrast masks or out-of-focusing some zones with pantyhose interposed between the objective and the enlarger plan, but the interventions are long, laborious, hard to perform and have a somehow limited impact on the acutance and the image grain.

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Add noise to remove noise

Fabiano Busdraghi — Thu, 11 Oct 2007 21:19:27 +0000

100% detail of a crushed image with bandings and evident artifacts. In this picture the digital noise has been strongly amplified by the photo editing that wanted to open shadows and augment the contrast.

Even if digital pictures noise is often related to analogical films grain, it is generally aesthetically less pleasant than the second one and it is better do everything possible not to have noise. Apart from useful hints while taking pictures, there are many great post-production systems to filter noise keeping the best of the detail, such as Noise Ninja, also available as a Photoshop plug-in.

Noise Ninja works for the majority of situations; it cleans images from its uniform noise zones, such as skies, leaving the detailed parts of the image almost untouched. Moreover, if it is applied with a border mask, such as the one produced by the script TLR Sharpening Toolkit, and a little of manual work to ameliorate the protection mask, the results are excellent.

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Inkjet black and white print on Epson 2100 inkjet printer

Fabiano Busdraghi — Sat, 29 Sep 2007 21:56:10 +0000

The first research about repetitive elements, 2007. Black and white print on Matte Paper Heavyweight with Epson 2100 calibration.

I’ve been always disappointed by black and white print that I obtained with my Epson 2100. A certain tonal dryness, but most of all unpleasant color dominants. Today I found myself in a position where obtaining acceptable and neuter prints was necessary, so I made some attempts with papers and settings till I found the right compromise. The article I’m going to write is not a deep tutorial on how to obtain black and white fine art prints using an Epson 2100. If you need the perfect b&w print, you need alternative third part ink and work with proper print Rip. The article is about some forethought that gives back decent b&w prints with lowest effort.

All of the papers I have tried, either opaque or brilliant, gave unsatisfying results printing only with the black ink, and using Photoshop color management and generic Epson profiles. Black are deep and I can not notice the resolution loss as the Internet forums say. But the response curve is strongly modified, flattening the middle tones. Therefore prints are smooth and without substance.

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Carbon print workshop with Damiano Bianca

Fabiano Busdraghi — Wed, 29 Aug 2007 15:55:08 +0000

Before every carbon print, Damiano Bianca accurately checks the paper tissue to ensure its perfection.

In July I attended a stage of carbon print held by Damiano Bianca. The stage has been programmed and structured with him and, for those who’re interested, it is possible to make arrangements for similar courses, individually deciding arguments, duration, modalities and subscription costs.

I took part in course every afternoon for almost a week, in Rome, inside the Damiano Bianca’s perfectly equipped dark room.

First day has been dedicated to a generic introduction of carbon print, followed by a practical demonstration by Damiano with materials he prepared before the lesson. Then he taught an argument per day, deepening the theoretical and practical aspect of each one.

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Influence of the black generation curve on color separation

Fabiano Busdraghi — Sun, 26 Aug 2007 20:23:22 +0000

During the course of carbon print, held by da Damiano Bianca, I discussed a lot with him about the problem of separating the black and color channels of an image, showing some results obtained matching grey scale with K canal in pigmented VDB prints.

Gypsy Madonna. Original file used to study the influence of black generation curve on color separation in VDB and pigmented print.

Damiano told me about an unknown and fascinating world, the one of the typographic print before computers came into our lives, when there was a precise professional figure whose task was to prepare different channels negatives, someone who only did that job, someone with the adequate knowledge to work, and all of that using only analogue materials. Therefore I was convinced by the importance of black generating curve, once it was exposed.

Color theory says that mixing equal amounts of cyan, magenta and yellow creates the perfect black. Actually though, because of pigments impurity, in the real world those three colors creates an unpleasant brown. This inconvenience is obviated, when printing in quadri-chromic, adding a fourth layer of black pigments that neutralizes shadows and gives deepness and prominence to the print.

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Links and manuals about digital negatives

Fabiano Busdraghi — Thu, 23 Aug 2007 13:11:48 +0000

Example of palette ready to be printed and used to determine the characteristic response curve of a cyanotype print on Schoeller Durex Satin paper.

The majority of alternative prints and historical processes require negatives of the same size of the final image. Photographers that use mammoth cameras can obtain them directly en prise de vue, while others must enlarge their negatives to obtain the desired image. There’s plenty of analogical techniques that produces negatives adapt for each alternative technique, but digital negatives printed on transparent films are getting more and more common.

The result is a cocktail between chemical photography that is 150-years-old and the most modern digital technologies. A good way to close the circle.

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K-channel or grey scale in pigmented Van Dyke Brown prints

Fabiano Busdraghi — Mon, 18 Jun 2007 10:34:36 +0000

Roscigno Proloco guardian. Original file used for VDB and pigments print.

A couple of years ago I printed some VDB on pigmented prints. It is a color print, obtained overlapping a ferric salts black and white print on a cyan-magenta-yellow inkjet print.

I think that one of the first photographer who used this technique has been Dan Burkholder, whom website contains wonderful platinum tirages with delicate pencil color. Ron Reeder proposes wonderful and similar images on his website too, where a detailed manual explains how to obtain those kinds of prints. These two authors prints on platinum instead of silver, but the technique is exactly the same.

The result I obtained in 2005 was nice, but far from Burkholder and Reeder’s. Colors vaguely remembered old handmade postcards spread in the first half of the 20th century, but their problem was brilliant pinks and pale greens in highlights, surely too saturated and luminous for me.

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