The ABC's of Image Posting

My goal here is to teach the process involved in getting photos from the camera to the computer to a Reef Central thread. Hopefully, this article will help speed up the process and improve the quality of images because, after all, time and quality are what it's all about!

After taking a photo, the next step is to upload it to your computer. If you directly connect your camera to the computer, I recommend investing in a card reader. They are not expensive, usually in the $20 price range and multi-format card readers (compact flash, secure digital, etc.) are available, too. There are distinct advantages to using a card reader, the main one being that the camera does not need to be present; no need to lug the camera to the computer, no need to plug in the AC adapter or to make sure there's enough charge in the battery to get the job done. Card readers also have the potential to be very fast. If your computer has a USB 2.0 or Firewire interface, download speeds can be very fast. Regardless of the speed, the ease of using a card reader compared to uploading from the camera makes it a good investment.

Once the pictures are on the computer and you've selected the image you want to post, the next steps are to touch up the picture and resize it for web viewing. If you need an image editing program, Irfanview is a wonderful program that does many of the basic functions and, best of all, it's free! Photoshop is the standard program used by graphics professionals the world over and if you have it, you're set; if not, don't worry. Irfanview, or any of the many other less expensive programs, can do the job nicely.

Here's a very important tip - never save the original file with changes made to it! Make sure you have a copy of the original unedited picture safely archived on your computer. If and when you make changes to the original, save the new picture as a separate file - that way you always have the original to fall back on if a mistake is made.

A few thoughts on deciding what dimensions your image should be are in order. Recent polls (Link 1, 2, 3, 4) show that the vast majority of computer users' displays are set at either 1024 x 768 or 1280 x 1024 resolution, so an image size of approximately 800 pixels wide is a very good starting point. Any smaller and it becomes hard to see detail, and as the size gets bigger, not only does the file's size increase but some people will have to scroll around to see the whole image. First, I will explain how to resize an image using Irfanview. Open a photo by clicking on File>>Open. Navigate to the folder that holds your photos and then select the image you want to work with, then select Image>>Resize/Resample. See screenshot:

In the Resize/Resample dialog box check the Set new size radio button and enter 800 pixels in the Width field. The height will be calculated automatically as long as you have the Preserve aspect ratio button checked. The DPI setting can be left at 72 because that is adequate for sharing your pictures on the Internet and anything greater is a waste of hard drive and bandwidth space. If resizing for print, you'll want to set the DPI higher. On the box's right side are some standard dimensions - using those are just fine too as long as the aspect ratio of your picture is the same as the standard size you choose. The default settings of Resample (better quality) and Lanczos filter can be left alone. Then click OK.

To resize an image with Photoshop, click on File>>Open, then navigate to the appropriate folder and select the photo. Then click on Image>>Image size. See the screenshot below

Enter the desired width (800 pixels in this example) and the height will be calculated automatically as long as the Constrain Proportions button is checked. Scale Styles and Resample Image [Bicubic] can be left in the default [checked] positions. The Document Size section of this dialog box can be ignored - again, that is typically used when preparing an image for print. Then click OK.

Before saving the image, you might want to do some basic enhancements to make it look as good as possible. For simple and effective enhancements in Irfanview, click on Image>>Enhance colors. You can adjust the brightness/contrast, make color adjustments and saturate the whole image if you so desire. Small adjustments are advisable. If the image needs more than that, then it's better to either choose another image or to take the photo again if possible. Once your adjustments are made, click OK. Next click on Image>>Sharpen. One click is usually enough and it is almost always necessary to sharpen images from digital cameras. Over-sharpening is easy to do, and it can seriously degrade the picture's quality as well as greatly increase its file size, so careful use of this feature is important. Unfortunately, Irfanview can sharpen only the entire image; Photoshop can sharpen specific portions of the image.

Obviously, Photoshop can do a lot more than Irfanview to manipulate an image, hence its hefty price tag. With your image open in Photoshop click on Image>>Adjustments - this is where adjustments are made to the brightness/contrast, color balance and saturation. The pros use Levels and Curves to fine-tune the exposure, and I highly recommend using theses tools but remember - small changes go a long way! Our goal here, though, is speed; quick changes can be made by using the Auto adjustments for Levels, Contrast and Color. It's likely, though, that the auto adjustment will be a little too much - not to worry, there is a quick and easy way to scale it back: click on Edit>>Fade Auto Levels. Make sure the Preview button is checked, and you'll be able to see the adjustment fade as the slider is moved to the left. That feature can be very valuable.

After making the color and exposure adjustments, click on Filter>>Sharpen. You can use the very simple Sharpen filter to sharpen the whole image by a default amount. If you choose that option and find that the image looks oversharpened, try clicking on Edit>>Fade Sharpen; this will open a dialog box with a slider that allows gradual reduction of the last filter/adjustment that was made. A more advanced (and recommended) way to sharpen photos is to use Unsharp Mask. Click on Filter>>Sharpen>>Unsharp Mask; this opens a dialog box that has three sliders. As a good starting point, set the Threshold to 10 and the Radius to 0.3. Your eye will have to determine the amount - and it'll be anything up to a level of 500:

The second half of the process of posting photos that shrinks the file's size is compression. It's a critical step, and choices made here will determine the picture's final file size as well as how the picture will ultimately look. Be careful, though; too much compression leads to a very small file but can also result in a picture lacking in detail. There's a good compromise but you just need to train your eye to find it! Look closely at any smooth areas that lack detail and watch for pixelation (blocky patches). Also look at any clear margins where there is a sharp line; if you see noise or pixelation there, the picture is either over-sharpened or over-compressed.

A big size savings results when the image is reduced to 800 pixels wide, and to reduce the file's size even more, try compressing the image using an image editor. First, I'll describe the steps involved when using Irfanview. Click on File>>Save as and two boxes pop up:

The largest box is a typical Explorer window that allows you to rename the image and place it into the desired folder. The smaller [gray] box is where the compression level is chosen. The more the image is compressed by sliding the slider to the left, the smaller the file's size will be. Generally speaking, a value in the range of 50-60 is a good place to start; much lower than that and artifacts (noise) will begin to show which can really take the impact out of a good picture. The default settings for this program are generally good; leave the first three boxes unchecked and the last three checked. A .JPG is the standard image format for posting images on Reef Central, so save all images in that format.

In Photoshop, the process has a few more options and allows much greater control. ImageReady is the file saving utility by Adobe; it's fast and efficient. If you have one of the more recent versions of Photoshop, it comes with ImageReady. To save an image with ImageReady click on File>>Save For Web and ImageReady will launch in a separate window:

The image appears with four tabs above it: one for the original uncompressed image, another for the image with the compression applied, a third tab that allows you to see a split-scene of the "before/after" versions, and a final tab that shows a preview of three different compression levels plus the non-compressed original. The compression level and the compressed file size are displayed for easy viewing and this makes things very simple since all the data is right there. With Irfanview, or by using the "Save as" method in Photoshop, you cannot see how the final version of the image will look without actually going through all the steps and then opening the saved image in a separate window. If it turns out that too much compression was used (e.g., you see noisy artifacts such as halos and or pixelation), then the whole process must be repeated.

As with Irfanview, a compression level of 50-60 is a good place to start. Images that have big areas of little or no detail, like a blue sky, will require less compression because artifacts are more visible in those areas than in other areas.

In the drop-down menu, be sure to select JPEG for the file type, check the Optimized button and set Blur to zero. The Quality drop down menu lets you control a slider for the compression level, but if you don't want to use the slider, the compression level's exact number can be entered in the Quality box. The Progressive and ICC profiles buttons should be left empty for this simple compression task. Below these buttons is another small box that allows quick image resizing, too - simply enter the desired image dimensions and that's all there is to it.

Now you have a file that is fit to display on Reef Central, or anywhere on the Internet for that matter. The next step in the process is to get the photo hosted on the Internet. If you don't have a website, don't worry - in addition to the free gallery provided to registered members on Reef Central, some very good, even free, image hosting services are available. A few such sites are: Reefbucket, Photobucket, Smugmug, Pbase, Flickr, Snapfish, Imageshack, TinyPic, The Image Hosting, and many more. Be sure to read the terms of service to make certain you retain the copyright to your photos and that the images are to be used only by you, the photographer.

After either going through the process of opening an account at one of the sites listed above or by using an existing website or Reef Central's image gallery, you're ready to upload photos. Uploading pictures to a web hosting site works like any file moving operation - there is a Browse button that allows you to navigate through your computer's file system; find the folder that holds the photo(s) to be uploaded and then click OK. It's as simple as that!

Some of the above-mentioned image-hosting sites provide the image's address (and sometimes even the source code with the tags already in place) right under the picture, so all you have to do is copy the address. Copy the address by dragging the mouse over the address while holding down the left mouse button; once the whole address is selected, and only the address (it typically starts with "http" and ends with ".jpg"), right-click and select Copy (for Windows users), or highlight and select Copy or Command C (for Mac users). If the address isn't so conveniently displayed, copy the image address from the address field at the top of your browser. The address will look something like this:

If the address at the top of the page does not end in ".jpg," the picture is most likely embedded in the body of the web page, and you'll need to follow a couple more steps to get to the photo's actual address. Right-click (for Windows users) anywhere on the image that you want to post and select Properties. In the dialog box that pops up you will see the address (URL) listed, and it will end in ".jpg." That is the address to copy (see screenshot below).

In a separate browser window, open the Reef Central thread you want to place your photo into. Click on the Post Reply button and look at the buttons above the field where you enter your text. Below the smilies, you will see a row of buttons for Bold, Italic, Underline, Font Size, Type and Color -the row below that is where you look. Click on the IMG button and a box pops up. You will see that an http:// is already there - this is to let you know that this is where the image's address goes. Paste the image's address into this box by clicking once in the box, right-clicking and then selecting Paste. You will see the address that you copied in the previous step appear in the box. Be sure that only one http:// is at the beginning of the address. Finish typing your reply, then click the Submit Reply button.

If you've followed the directions and your photo does not appear, then the first thing to check is that there aren't any typographical errors (using the copy/paste feature is highly recommended). Also make sure that the address of the photo ends in ".jpg;" if it doesn't, you are probably copying the address of the wrong file. Another possible error is clicking on the wrong button in the vB code section - make sure you click on the "IMG" button and not the "http" button. Extra spaces in the address box can cause the image to not be displayed too - be careful to copy only the picture address, the whole address and nothing but the address!

Additionally, some websites use anti-leaching code in their pages to prevent other sites from using (stealing) their bandwidth. A byproduct of the code is it can cause trouble with firewalls; if you're seeing red x's where graphics or picture files should be, the problem may be caused by the anti-leaching code conflicting with too strict firewall settings. Check to see if your firewall is set to stealth-mode - if it is, try a less strict protection mode to solve the problem.

You are now an expert image poster!

If you have any questions about this article, please visit my author forum on Reef Central.

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The ABC's of Image Posting by Greg Rothschild -