Photoshop Tall and Thin, Big and Flat: New Cache Tile Optimization Options in CS5 - Photo Tips @ Earthbound Light

Eredeti: Bob Johnson, Earthboundlight

Photoshop Tall and Thin, Big and Flat: New Cache Tile Optimization Options in CS5 Because digital camera resolution continues to increase over time, the image files most of us work with get bigger too. Thankfully, computer processing power and memory also keep going up so we can work on those bigger images. To better manage all the memory needed to push around huge numbers of pixels, Adobe has added new tuning options to Photoshop CS5 that may need a bit of explaining. Photoshop has long given the user a degree of control over how memory is allocated and used. Originally found on the "Memory & Image Cache" Preferences tab and later moved to the new "Performance" Preferences tab as of Photoshop CS3, we've had control over two basic memory tuning parameters. The most straightforward setting is the maximum percentage of available memory used by the program. If your computer was dedicated to nothing but Photoshop you could afford to set this relatively high, but if you typically ran other applications at the same time, you could lower the value so that Photoshop wouldn't completely monopolize your machine. Photoshop also has long given users control over the number of cache levels employed to improve responsiveness of the display. With caching enabled, Photoshop maintains the specified number of lower resolution versions of your open images and updates them while you edit. If you aren't actually zoomed into a 100% view of an image, using one of these cached versions as a basis for rendering what you saw on your screen allowed Photoshop to keep display redraw up-to-date more easily. Photoshop can also used these cache versions as the basis for displaying image histograms. Current versions of Photoshop default to four cache levels. If you set this to one, caching is disabled and Photoshop will only maintain the actual pixels for opened images with no additional low resolution versions. Photoshop CS3 also gave us control over the number of History States to maintain in the History panel. Since each one consumed memory, it was a tradeoff as to whether you wanted the ability to undo more edit steps or preserve more memory for processing the active image state. More control over how memory is used is good so this was a welcome addition. In Photoshop CS2, Adobe introduced the "Bigger Tiles" plug-in intended to improve performance for those with more than one gigabyte of memory. That doesn't sound like a lot of memory at all by today's standards, but back then it was. Without realizing that's what they were called, you are probably already familiar with the concept of "tiles" in Photoshop. When you perform any kind of significant edit you can see Photoshop redrawing your display in large blocks. Those are tiles. Photoshop will perform the needed calculations for a filter or other edit on these blocks or tiles of memory one at a time, moving from one to another until the entire image has been updated. The default tile size in CS2 was a measly 132 KB so a large image would consist of quite a few tiles. When you installed the Bigger Tiles plug-in, the default increased to 260 KB but if you assigned at least a gigabyte of memory to Photoshop, the tile size jumped to a full megabyte each. This allowed Photoshop to process larger chunks of your image at a time, allowing it to get the entire job done in fewer steps and thus finishing more quickly. Some users reported great success using the Bigger Tiles plug-in but others claimed they got little if any improvement. I found it helpful and this was one of the things I always changed when installing Photoshop on a new machine. The plug-in could be installed by locating it in your standard Photoshop plug-in folder and removing a leading "~" from its file name. On Windows, it generally lived at "C:\Program Files\Adobe\Adobe Photoshop CS2\Plug-Ins\Adobe Photoshop Only\Extensions\Bigger Tiles" under the name of "~Bigger Tiles.8BX." By taking the "~" off and restarting Photoshop, the tile size change would be active. In Photoshop CS3 it moved to "C:\Program Files\Adobe\Adobe Photoshop CS3\Plug-Ins\Extensions\Bigger Tiles" but worked the same. For some reason, with Photoshop CS4 you had to hunt the file down on your installation DVD and copy it in place but it still existed and still did the same thing. Finally, as of Photoshop CS5 you no longer have to rename some secret file of track down that file on your Photoshop DVD to change the tile size. Now you can control the tile size directly from the Preferences dialog. I guess Adobe has realized that most of us now have more than a gigabyte of memory. Located in the Photoshop CS5 History & Cache section of the Performance tab of Preferences you'll find the same History States and Cache Levels settings we've had for the past few releases. But you'll also now find several new controls here as well. Notably, there is now a drop down setting box for the Cache Tile Size to give you direct control over the same thing the Bigger Tiles plug-in previously affected. By adjusting History States, Cache Levels and Cache Tile Size you now have a tremendous amount of control of Photoshop's memory management settings. It is still necessary to restart Photoshop for any changes here to take effect, but by iteratively tweaking these settings to fit your needs and the type of images you generally work on you should be able to coax a reasonable performance improvement from Photoshop. In an attempt to make picking the optimum values for your situation Adobe has provided three new buttons at the top of the History & Cache settings with the cryptic names of "Tall and Thin," "Default," and "Big and Flat." Photoshop will optimize the values of History States, Cache Levels and Cache Tile Size based on which of these three buttons you click on. It's safe to assume that the Default choice lies somewhere between "Tall and Thin" and "Big and Flat," but thes other two are less clear. According to Adobe, "Tall and Thin" is intended for those who typically edit small to modest sized images with a lot of layers while "Big and Flat" is for those who often edit images with larger pixel dimensions but with fewer layers. I'm not sure I could have come up with any better names for these buttons but the ones Adobe chose sound a bit odd to me until you think about what they mean a bit but there you have it. The exact values you will end up with will vary based on your hardware configuration. Those with more powerful Photoshop workstations will see more variation in the results of the three buttons while those with more modest setups may see Photoshop pick basically the same values for History States, Cache Levels and Cache Tile Size regardless of whether they go with "Tall and Thin" or "Big and Flat." If you've upgraded to Photoshop CS5 I encourage you to experiment some with these cache settings. You may just find that the time it takes to do so will be more than paid back with a faster, more responsive program.

Date posted: July 11, 2010

Copyright © 2010 Bob Johnson, Earthbound Light - all rights reserved.

Adventures in Close-Up Photography | Layers Magazine

Eredeti: Rick Sammon, Layers Magazine

Adventures in Close-Up Photography

By Rick Sammonin Columns 
Wednesday August 13, 2008

Close-up photography allows us to capture a unique view of our world, especially when that world is printed larger than life. Capturing small subjects requires careful attention to the technical aspects of photography: focus, lighting, sharpness, depth of field, exposure, and composition.

All of these factors came into play with the image of the red-eye tree frog (above left), photographed with a Canon EF 50mm f/2.5 Compact Macro lens and ring light. (The black background in this picture was created by holding a black T-shirt about two-feet behind the subject—far enough so that it wasn’t illuminated by the ring light).

For newcomers to the fascinating, fun, and rewarding aspects of close-up photography, this article introduces a few of the basic techniques.

The macro lens

For true macro photography, you need a macro lens, as opposed to the macro/close-up setting on a zoom lens. Macro lenses let you get much closer to a subject than zoom lenses. This picture of a newly hatched butterfly was taken with a Canon MP-E 65mm f/2.8 Macro lens, which offers tremendous magnification—much like a bellows system for SLR cameras. It’s a specially designed, manual focus macro lens that actually lets you fill the frame with subjects as small as a grain of rice.

The remaining photographs in this article were taken with more commonly used macro lenses: 50mm and 100mm. The main difference between these two lenses is that that 100mm lens provides a greater camera-to-subject distance so you don’t frighten skittish subjects, such as butterflies.

Getting close

Okay, let’s move on to some macro shooting tips and techniques.

Steady your shots: Macro lenses exaggerate camera shake, as do telephoto lenses. To reduce the chance of a blurry picture caused by camera shake, which is most noticeable in natural light pictures, you need to use a tripod. I used a tripod with a ball head (for easy positioning) when I took this natural light photograph of an Atlas moth with the 100mm f/2.8 Macro lens.

Compose carefully: The background can make or break a close-up picture. Try to compose a picture so the background complements the main subject and does not detract from it.

Add a background: If the background is too distracting, you can change it. Photograph a leaf, make an inkjet print, and use the print as a background. For more creative control, try blurring the leaf in the digital darkroom (using the Gaussian Blur filter in Photoshop) to simulate the effect of using different f-stops.

Add light: When adding light, a ring light is a good choice. A ring light attaches to the end of a lens and can provide ratio and even (“shadowless”) lighting. The light from a ring light also adds contrast to a picture, making it look sharper than a natural light photograph. A Canon Macro Ring Lite MR-14EX attached to the front of the 50mm macro lens was used for this picture of a cabbage white butterfly.

Focus carefully: In close-up photography, as with telephoto photography, focus is extremely critical. You need to focus on the most important element in a scene, such as the eye of an insect or small animal. It’s also important to shoot at a small aperture (f/11 or f/22) for good depth of field (unless you want the area in front of and behind your subject out of focus). I set the 50mm macro lens at f/22 for this photograph.

Set the white balance and image quality setting: When using a ring light as the main light source, set the white balance to Flash. When the light is mixed (daylight and flash), set the white balance to Auto.
For the very best quality image, set the image quality to RAW. The RAW setting gives you a little more exposure latitude (is more forgiving) than the Fine or High JPEG setting. What’s more, with a RAW file you’ll have less chance of getting banding in solid colors and dark areas, such as the black background in the opening image for this article.

Experiment: It’s important to be aware of how different angles and different shooting distances can greatly affect a picture. In close-up photography, moving just a few inches, or a faction of an inch for that matter, can provide a completely different view of the same subject, as illustrated by these two pictures of an orchid, which I took with the 50mm macro lens. Also play around with different color modes, including black and white.

Okay, now it’s your turn to have fun exploring your own close-up world!