We’re all quite happy with the technical capabilities of cameras these days and their ability to capture the finest of details, though sometimes it’s best to do a bit of clean up work so as to end up with a truly flattering portrait.

Brightness, color and contrast adjustments: To make the best of prints with detail everywhere, it’s best to take pictures a bit “flat”, without much contrast, with the exposure optimised for the highlights. Hover over this picture of a balcony terrace on rue rue Beaurepaire to see the picture as I took it.

Perspective correction: hover over this picture of Sacré-Cœur to see the uncorrected version.

Digital trickery: remove bothersome elements from your pictures as you wish! Hover over this picture to see the truck disappear; take a look at a bigger version of this example.

Image sharpness optimized for display on a web page. Hover over this picture to see the results of a reduction from a high-resolution scan, without boosting the sharpness.

The “Image Size” dialogue box where you can set the print size, and if necessary, the number of pixels in the image.

The “Curves” dialogue box is the best choice for working on the brightness, contrast, and color balance in a photograph. I prefer this method by far as opposed to others, notably Levels. This screen shot shows a typical curve for increasing the contrast of a picture

These Photoshop classes, entirely tailored to your needs and what you would like to learn, can help photographers with these subjects:

1. Portraits: How to minimize skin disturbances, shadows around the eyes, wrinkles, acne, the “five o’clock shadow”, without losing apparent sharpness. Bring out the best in your portraits while avoiding the “silly putty” look, or pictures that look too much like those on the covers of teen magazines.
2. Brightness, contrast and color balance: how to adjust these three at the same time, or separately, with the “Curves” dialogue box, with which one can modify colors in a “non linear” manner, which the “Levels” dialogue box does not allow.
3. Nighttime photography: photographs taken at night or inside often have an overall red or yellow cast, because of artificial light, such as tungsten bulbs. Learn to correct these color casts without making areas of the picture too blue or cyan.
4. Perspective: Straighten out converging lines in pictures taken with the camera pointed up or down. Pictures of buildings generally have “keystone” distortion, unless the picture is taken with the film plane parallel to the building façade. Before the arrival of digital photo retouching, the only solution was either to use a perspective-correcting lens, or to take the picture with a large format field camera.
5. Selections: Just about always, you’ll want to modify brightness, contrast and color balance region by region. To do so, you need to make selections: with the polygonal Lasso tool, in “Quick Mask” mode, with the “Color Range” command, or with a combination of these three. The subject of selections is perhaps the most complex and the most difficult to understand, so much so that sometimes it’s better to skip it and use the “History Brush”, to return the areas on which you click as they were when you opened the file.
6. Digital trickery…This isn’t really my thing, and I try to take my pictures in ways such that I will not need to work them over much in Photoshop. That said, from time to time I do find myself removing trees rising from behind people’s heads, towing away bothersome trucks, picking up litter on sidewalks, etc.
7. Sharpness: How to increase the visual sharpness of your pictures without going too far. These days I see pictures (in photography magazines, even!) whose sharpness has been pushed too far. Usually this is noticeable because there are thin white lines along the edges between bright and dark areas.
8. Image size: How to set the resolution for a given print size, learn when you should “up-sample” so as to avoid seeing pixels in an enlargement, or downsample to reduce file size.
9. Reduce film grain and eliminate “noise”: To do so, I like the “Dust and Scratches” filter, and I’ve learned different ways of applying this filter selectively, so as not to lose detail, using layers and the Eraser tool.
10. Calibrate your screen and the rest of your digital photography process: It is essential to be able to trust the colors and contrast displayed on your computer so as to be able to make prints that resemble what you see on the screen. This isn’t just a question of calibrating the monitor; the settings on your camera or scanner should be looked over, as well as your printer if you make your own prints.
11. Learn about file formats: In digital photography we have Tiff, Jpeg, Photoshop, Raw and Gif. Tiff offers little or no options for compression, keeps all the quality of an image, JPEG offers variable compromises between file size and image quality, the native Photoshop format should be used when working with layers, the Raw format is generated by digital cameras and is thus an import format, and the only reason for using the GIF format is for preparing pictures for the web with a non-rectangular border. Learn how to use these formats, when and why.
12. 16 bit mode: Images with this color depth have an extended range of brightness as compared to 8 bit files, albeit “hidden behind” the eight bits that computer monitors display. The great advantage of 16 bits is that one can more easily recover details otherwise hidden in the highlights and shadows, above all in pictures with a lot of contrast. Photo labs do not accept 16 bit files, because the JPEG format only allows 8 bits. I take my pictures in the Raw file format, which allows me to open them in 16 bits, giving that much more depth and exposure latitude. Once I’m finished working on the picture, I switch to 8 bits, and save the image in JPEG format in order to archive it, or send it for printing.
13. Prepare pictures for display on web pages: Oddly enough, it isn’t enough to reduce images with the “Image Size” dialogue box. It’s better to do the reductions (at least twice if working from high resolution images, 2,000 x 3,000 pixels), while boosting the sharpness with each reduction. Also, I’ve occasionally found it necessary to brighten the image before making the final reduction as so many original pixels are being glommed together in order to interpolate the web version’s pixels.

Write me a note if you would like to sign up for Photoshop lessons!

Pay on-line for one workshop session, or for two or more workshops sessions.

As seen in «Réponses Photo» Left: an announcement for photography lessons by David Henry printed on page 154, in the October 2005 edition of one of the leading photography magazines in France.

Questions and answers about Photoshop workshops:

Who is David Henry? I’ve been taking pictures since the age of thirteen. Most of my work consists of tourism and travel photography, for advertising agencies, graphic designers, architects, books, magazines and other kinds of publications. I first started digitally manipulating photographs at the beginning of the 1990s. A few years later I was preparing pictures in layouts for high-resolution offset printing. The great leap forward occurred six years ago, when I bought a computer and a scanner up to the task, worthy of making prints of truly photographic quality, at very large sizes. A typical scene with lots of contrast: It’s frustrating to not be able to expose for the foreground and the background at the same time. In this example, the easiest way is to take one picture exposed for the stained glass window, and another exposed for the interior of the church, and to combine the best of the two images. Along the way, I corrected the perspective in this picture also. Why retouch pictures, why Photoshop? Of course one can have pictures taken with a digital camera printed without doing the least bit of retouching. And if the pictures have been exposed well enough, many of them will come out fine. In the history of photography, truly the best prints are ones made by hand by someone with an enlarger. Seventy years ago there was no such thing as “custom printing”, because automatic printing machines had not been invented and every print was made by hand in a darkroom. It’s impossible to print digital pictures with an enlarger, so to replicate this sort of work, Photoshop is necessary. Doesn’t the term “retouching”, imply trickery or cheating? For twenty years I developed my negatives and made black and white prints in the darkroom with my enlarger. When doing so, I systematically made areas lighter or darker, activities known as burning and dodging. Even though I use a scanner and Photoshop to make my prints, I still have these same habits, except that now, I can do all this in color, something too difficult, slow and expensive to do in a darkroom. I have retouched all the pictures you see on this web site, some more than others, but always in the spirit of making “custom, hand-made prints”, as opposed to machine-made prints. I’ve found that any scan benefits from a boost in sharpness, adjustments of color balance, and above all, pulling out details in the highlights and shadows. But I don’t often engage in what could properly be called trickery, beyond picking up litter or removing trees rising up behind people’s heads. When are the Photoshop lessons held? Workshop sessions are in no way pre-organized, they are scheduled according to your availability. It is best to reserve sessions one or two weeks in advance, to make sure I will be in Paris, and not previously engaged. You may look over available dates, below.

What previous skills and knowledge are required for participants? I work with people of all kinds of skill levels, from absolute beginners to people who know Photoshop better than I do in certain ways. Participants need not know anything about digital photography, the only requirement is a will to learn, and the motivation to put in to practice the ideas and concepts I teach. Where are these Photoshop classes taught? I feel it’s best to teach and learn on your own equipment. That way, I can look over your digital photography process from beginning to end; from image acquisition (your digital camera or scanner), your computer and the calibration of your monitor, on up to your printer, or your habits of working with digital photo labs. Otherwise, I can teach anywhere with my Macintosh PowerBook G3 with Photoshop 6, or we can work at my studio, on my Intel iMac with Photoshop CS4. Why these Photoshop lessons? It must be said that Photoshop is truly a flexible program, used for dozens of kinds of work on images, having to do with science, graphic arts, cartoons, astronomy, video, etc, as well as… photography. If you take traditional classes on Photoshop, you’re likely to learn plenty of things of no interest to photographers: typography, vectorial drawing, drop shadows, “artistic” filters. My approach is to teach Photoshop for photographers, the most important parts of the program for bringing out the best in your pictures, as you would if working with an enlarger in a darkroom. How many students are there per class? Most of the time, there is just one participant: you! That is, unless you would like to participate with friends, in which case the rates are the same. These workshops are entirely customized, one-on-one sessions. You may think of these sessions as an opportunity to learn techniques I have gathered over the years and to “pick my brains”, and ask specific questions that most people wouldn’t have the answer to. What kind of equipment is necessary? Just about any computer made in the last four years can run Photoshop, as long as it has enough RAM (a gigabyte is a comfortable amount) and has a few gigabytes of free space on the hard drive. If you do not have Photoshop installed, Adobe offers a trial version which lasts 30 days. If you will be using Photoshop more than a little bit, I strongly recommend a graphic tablet, like those made by Wacom.