Product Reviews

PTGui, a dedicated panorama creation tool from small Dutch developer New House Internet Services, has been around for a long time as a Windows application, but with the release of PTGui 6 it now also runs on Macs. Along with the recent updates to RealViz Stitcher and Adobe's Photoshop CS3 beta, PTGui provides yet another way to stitch multiple photos together into large, panoramic images.

Like a number of other panorama utilities, PTGui is based on the highly respected open-source Panorama Tools algorithms. PTGui takes a number of overlapping images, finds matching elements across the different images, and produces a blended, merged result with extraordinary accuracy. Although you can use it to stitch all kinds of multi-part images, including 'flat' stitching from scans of large images, it is normally used to generate panoramic images for use as VR panoramas - not just as QuickTime VR movies, but also using Flash or one of the various Java VR engines, or as high-resolution images for print.

Unlike products such as RealViz Stitcher or VRWorx, PTGui doesn't produce actual VR panorama movies. Instead, it produces stitched images ready for production using other specialist tools. This may seem like a weakness, and it is true that if you want to create a VR movie from PTGui's output you'll need to use a utility such as Helmut Dersch's PTViewer (for Java delivery) or Click Here Design's CubicConverter (for QuickTime VR). Alternatively, it could be seen as a strength, as all its development is focused on refining the stitching process and accuracy. This also makes final stitched panorama image adjustment in Photoshop a logical part of the workflow, if desired, rather than an interruption, and layered Photoshop files can

When PTGui is given images with a reasonable amount of detail, its ability to find matching points in adjacent images is simply uncanny. Depending on your originals, you might be warned that some control points may be misplaced, or that one or more images have no control points generated. These problems are corrected using the Control Point Assistant and the Control Points panel, where you're given a detailed rundown of the accuracy of every control point, and the option of adjusting point pairs manually to improve the joins.

When shooting images for use as VR panoramas, a dedicated VR tripod head can help a lot, but handheld shots of a scene can often be stitched almost as well. As long as there's enough image overlap, PTGui will find sufficient matching points and, if necessary, help you refine those and create more.

When you're ready to produce a final image, you can create it at the resolution you want, as a Tiff, Jpeg or Photoshop-format image (including a large-format PSB), and at 8-bit or 16-bit colour per channel. Tiffs and Photoshop images can consist of a flattened composite, individual layers, or both. But be ready for large file sizes: a ten-shot panorama in full-layered Photoshop format can take well over 300MB.

The interface is a workflow-oriented one, with tabs taking you through the process - from the initial Project Assistant, through to Control Points, and finally Create Panorama. The Simple version has three different tabbed sections. Click the Advanced button and you get ten tabs to play with, although some of these contain settings only the most fearlessly technical will need.

PTGui is an excellent tool for creating panoramas quickly and without fuss, and the results proved to be both sharp and accurate, even with full 'cubic' panoramas, including a full 180 vertical view.

This is designed to be part of a serious panorama production workflow, not a one-stop shop. It is aimed at users prepared to do a bit of work if necessary - for example, where images don't show enough detail for automatic control points - but does a good job of making the process of stitching images together as smooth as possible. Team it up with the right utility for turning its output into your preferred delivery format, and you have a superb combination.