Jud Dagnall Photography Blog

Photography, technology and occasional rants!

A few cool new photo sites

Posted on September 29th, 2005 in , , by jud || No Comment

Here are a few sites that I discovered recently:

Techniques and tips, including good information on measuring the black point of your printer:

Cool nature photos from the winner of this year’s Popular Photography contest:

Microsoft is getting into the photo game with some useful content:

Microsoft Professional Photography

Using unsharp mask in ImageMagick

Posted on September 19th, 2005 in , , , by jud || No Comment

ImageMagick is an open source, free, cross-platform set of image processing command-line tools. I use IM to process some of my images for presenation on the web. The sharpening functionality (unsharp mask) is not very well documented, and I found a pretty thorough explanation of
how to use unsharp mask in ImageMagick.

Canon Flash Photography

Posted on August 29th, 2005 in , by jud || No Comment

Getting good information about flash photography can be difficult. Here’s a site that’s all about Canon flash photography.

DPI doesn’t matter for web graphics!

Posted on August 2nd, 2005 in , by jud || No Comment

I see a lot of questions regarding the resolution (DPI or dots per inch) of web images. There is clearly much confusion about how to size images for the web. So here goes…

The image DPI resolution does not matter for the web. I don’t know of any web browser that pays any attention to this setting. Image pixels vs. monitor resolution determine the size of web images. Monitors are at a fixed resolution (they only show a certain number of pixels at a time, typically between 800×600 and 1600×1200). So a 600×400 image will be about 1/4 of the size of monitor at 1200×800, regardless of the DPI setting. Just to confuse things a bit, most monitors the US are now at 1000×800 or 1200×1000 pixels, and this will continue to grow as larger monitors become cheaper. And finally, many modern browsers will resize large images so that they fit onto the screen, and then provide a magnifying glass (or some other tool) that allows the viewer to see the full size image by clicking on it.

Keeping your images under 600 pixels wide (and ~400 pixels high) allows the majority of people (on the majority of monitors and browsers) to see the whole image on the screen without having to scroll, including any other things that the website puts above/below/beside the image, like borders, navigation, ads, etc…

Because most monitors are in landscape orientation (wide not tall), the max height of web images should be smaller than the max width (once again to prevent scrolling). This is also an issue when using a digital projector… vertical format images get shrunk (or cropped) more than horizontal images.

For example (ignoring all margins for simplicity), if I have my monitor set at 800×600, I can just display a horizontal image that is 800×600 pixels. However, the same size image in vertical format (600×800) won’t fit (the image height at 800 pixels is greater than the 600 pixels my monitor can display). So I need to shrink the image down 25% to 450×600 pixels so it will fit vertically.

Scripting Photoshop: Text basics

Posted on May 11th, 2005 in , by jud || No Comment

I’ve been working with photoshop javascript scripting, which is relatively simple. For example, as an experiment, I’m in the process of automating the way I frame images for the web. This little script is step one in the processes, and provides a bit more detail about manipulating text. Copy the code to a file called Sign.js, and place this file in your *photoshop*/Presets/Scripts folder, and (after restarting photoshop) you can run it from the File->Scripts menu as “Sign”.

Note: I tested this code using Photoshop CS. It should work on CS2, and on Photoshop 7 with the scripting component installed, too.

// Sign.js - put your name in the lower right corner of the document
// preserve the existing settings before changing them
var strtRulerUnits = app.preferences.rulerUnits;
var strtTypeUnits = app.preferences.typeUnits;

// set our units to what we expect
app.preferences.rulerUnits = Units.PIXELS;
app.preferences.typeUnits = TypeUnits.POINTS;

// creates a new document, 400x600 pixels @ 72DPI, with a title "Hello World"
var docRef = app.documents.add( 400, 600, 72, "Hello, World!");

app.displayDialogs = DialogModes.NO

// Create a text color (red)
var textColor = new SolidColor;
textColor.rgb.red = 255;
textColor.rgb.green = 0;
textColor.rgb.blue = 0;

// Create the text layer that we'll manipulate
var artLayerRef = docRef.artLayers.add();
artLayerRef.kind = LayerKind.TEXT;

var textItem = artLayerRef.textItem;
textItem.justification = Justification.RIGHT;
textItem.font = "Papyrus"; // this is a Mac default font. Try "Arial" for cross-platform compat
textItem.contents = "Jud Dagnall";
textItem.size = 10;
textItem.color = textColor;
textItem.position = Array(400, 575);

// The next two steps aren't terrible relevant, but are part of the greater plan :)
// flatten the image
// make the background layer edit-able,
docRef.layers[0].isBackgroundLayer = false;

// clean up and restore settings
app.preferences.rulerUnits = strtRulerUnits;
app.preferences.typeUnits = strtTypeUnits;
docRef = null;
textColor = null;
newTextLayer = null;

Mark Hatasaka’s Digital Landscape Photography

Posted on March 10th, 2005 in , , by jud || No Comment

I recently had the pleasure of meeting Mark Hatasaka, a professional nature photographer and author of two books on digital photography. While both of his books are very impressive and packed with useful information, I was really blown away by his most recent book, “Mark Hatasaka’s Digital Landscape Photography”. Both books are full of stunning images taking with a variety of digital cameras, ranging from compact digitals (which he advocates because of their convenience and use in capturing images other cameras can’t reach) to high end digital SLRs.

What I find most useful about his books is his overall approach to photography, which is to concentrate on the essentials, and focus on
those techniques which will allow you to rapidly progress as a photographer. For example, he advocates what he calls “high volume digital photography”, taking a very large number of pictures, bracketing compositions and exposures, and then carefully examining the results. Digital cameras are an incredible teaching tool, because you can experiment with new techniques, variations and (almost) random chance. By taking a large number of pictures, you become intimately familiar with how your camera responds to a wide variety of situations, you are able to record your photographic thought processes for future reference, and you have a visual record of what works, what ALMOST works, and what doesn’t work at all.

I have typically shot primarily RAW images. Mark advocates shooting highest resolution JPEG images for most landscape and nature photographs, arguing that the advantages of being able to take (and process) 3 to 4 times as many images with the same storage, battery and time requirements outweights the extra security (and detail) provided by a RAW file. Although I continue to pursue my own independent investigation, I have begun trying his techniques and in just the first week had learned more about how my camera handled exposure and depth of field by bracketing (and comparing) multiple hi-resolution jpegs instead of trying to post-process my RAW images in Photoshop.

I highly recommend his books to all serious students of photography. If you are new to photography and are looking for a way to take better pictures quickly, buy his book and follow his techniques. If, like me, you have been honing your skills for a number of years, there are still plenty of jems, and the photos themselves are woth the price of the book. As of this moment, only his first book Digital Nature Photography is available on his site, but if you contact him, I think you can purchase it directly. I also understand that Keeble and Schuchat Photography in Palo Alto, California, carries one or both.

I honestly think that had I gotten his book and began rigorously applying his techniques years ago, I would have progressed much faster as a photographer.

Selecting “keeper” photographs

Posted on March 10th, 2005 in , by jud || No Comment

Much of my growth as a photographer has come from rigorously examining, comparing and ranking my own photos. This ongoing exercise has forced me to determine what works and doesn’t work every time I shoot by comparing photos with similar (or sometimes wildly different) subjects, compositions, lighting, depth of field, and/or other elements.

Alain Briot has an interesting article about how he selects his photographic “keepers”. I found it interesting because he goes into a fair amount of detail about not only the different reasons for selecting keepers, (commerical sales, personal enjoyment, years of viewing pleasure and discover, a “best of each location” album, same location in different seasons, etc.), but also some of the tools he uses and also some of the techniques he uses both to manage these collections, and to solicit useful feedback from other people.

Redundant equipment for photographers

Posted on December 23rd, 2004 in , , by jud || No Comment

One of the things that I stress to people who want to invest their time (and perhaps money) on photography trips is the importance of redundant equipment. Two years ago, I discovered first hand how devasting this can be. I had 5 days off, and had planned a trip to Mono Lake. Getting there during the winter took almost 2 days, since I drove up through Reno and then down 395 (I’ll be trying a new route this Christmas, along HW 88). I arrived just as night was falling, jumped out of my car, ran through the deep snow and snapped a few test pictures. The next morning, I got up nearly 3 hours before daybreak. It was nearly an hour hike through thigh-deep snow in the dark to get to the edge of the lake, where I settled in to await the sunrise. About 15 minutes later, my camera died. I should say, my ONLY camera died. Completely. Banging and cursing didn’t help. Power cycling. New batteries. Fervent prayers. Incantations. Sacrifices of small snow creatures. All to no avail.

At least I got to enjoy a spectacularsunrise.

And since I had no camera, the rest of the “photography trip” was shot, and I left for home that afternoon. Fortunately, one of my test shots turned out ok, and so the trip wasn’t a complete photographic disaster.

Now, with the purchase of the 20D, I finally have 2 cameras that I am happy using. Of course, I wouldn’t recommend buying two new cameras to get started (unless of course you have the budget). That’s why I got the Canon G6 last month, as a smaller, cheaper backup camera. (However, as I noted, I am upgrading already!)

Because my cameras are DSLRs, I have a variety of lenses that I can use. In fact, becuase I have a mix of prime lenses and zooms, plus a teleconverter, in a pinch I could get very close to the same focal coverage losing any one lens.

I have 3 memory cards (2 x 1GB, and 1 256). Again, I can lose 1 without any problem.

I keep my images on a laptop, and on a portable hardrive (mindstor by minds@work, now out of business). One dropped/crashed piece of equipment, and I’m still ok.

I have 4 batteries and 2 chargers (car and wall)

There is no single point of failure (except the photographer!), and so if I’m going to spend a fair amount of money on a 4-7 day photography trip, I can be sure that
it isn’t my equipment that stops me.