john_houghton

<p>If you're not using a resolution inadvertently by selecting a preset crop, I don't know what you might be doing wrong. However, you can alternatively crop with a rectangular selection via Image->Crop, which should solve the immediate problem</p>

<p>You are not alone in noticing this change. See forum thread: <a href="http://tinyurl.com/ahlpk86">http://tinyurl.com/ahlpk86</a></p>

 

<p>PTGui and Hugin are both capable of delivering the highest quality results. To claim that they don't deliver good resolution or that they introduce some barrel distortion is nonsense. They are extremely versatile programs that offer manual intervention at every stage such that all sorts of unusual situations can be dealt with effectively - at least by someone experienced in their use. They are not programs learned in an hour or two, it is true. "Best" will mean different things to different people, and some will give ease of use a high priority. I have used PTGui for 12 years and not found anything better for my purposes, but other stitchers can give equally good results for many sets of images. However, PTGui can also give excellent results for sets of images that most of the others simply cannot cope with at all. These would include shots taken with fisheye lenses that are commonly used for spherical panoramas. It will even produce a panorama from a single fisheye image and remove every trace of that extreme barrel distortion. You can find many samples of panoramas stitched from images shot with an assortment of cameras and lenses on my web site:<br>

<a href="http://www.johnhpanos.com/">http://www.johnhpanos.com/</a></p>

<p> </p>

<p>I would advise taking advantage of the current Microsoft Windows 8 upgrade for $40. It's a true bargain. You can optionally download an ISO image for burning to a DVD, which simplifies reinstallation should that be necessary at any time. I can also recommend downloading Start8 to restore the Start button (aka "orb") if you want it to look and feel like Windows 7. </p>

<p>I've not had any problems running Photoshop on Windows 8 Pro. It's very little different to Windows 7 when running in desktop mode (which in my case is most of the time), and the colour profiles are just where you would expect to find them. The Start8 download will restore the missing Start button very nicely.</p>

<p>Details of Canon profiles can be found in this (rather old) document:<br>

<a href="http://www.photokaechler.com/files/Canon_Profile_Guide.pdf">http://www.photokaechler.com/files/Canon_Profile_Guide.pdf</a></p>

<p>The updated Camera Raw is also available for CS5 from the usual Adobe site.</p>

<p>When creating a fake sky, you really need to do two gradients - vertical and horizontal - to match the vertical and horizontal colour changes. Do this in 16bit mode and add a little noise to the result to match the rest of the image. </p><div></div>

<p>An excellent fibre based glossy paper is Oriental Graphica:<br>

<a href="http://www.orientalphotousa.com/graphica.htm">http://www.orientalphotousa.com/graphica.htm</a></p>

 

<p>I see very little difference bewteen the two images. What slight difference in sharpness there is is easily restored by applying a small amount of sharpening, which is usually done as a matter of course after resizing down.</p>

<p>Seek out a copy of the book "Real World Image Sharpening with Adobe Photoshop" by Bruce Fraser (Peachpit Press). It should provide much of the information you require. </p>

<p>Ideally, in addition to yout tripod, you should use a spherical panorama head to enable the camera to be rotated left, right, up and down whilst keeping the entrance pupil of the lens in a fixed position (to avoid parallax effects). See:<br>

<a href="http://www.panoguide.com/howto/panoramas/panohead.jsp">http://www.panoguide.com/howto/panoramas/panohead.jsp</a></p>

<p>The front runners in the stitching software stakes are:<br>

Microsoft ICE (free)<br>

Hugin (free)<br>

PTGui<br>

Autopano Pro/Giga<br>

PTAssembler</p>

<p>All of these are capable of producing first class results. They vary in terms of ease of use and versatility but all are available on a free trial basis.</p>

<p>I have a 5D mark II myself with a Nodal Ninja panorama head, and stitch with PTGui, which I have used for more than 10 years and found nothing better for my own purposes. You can see samples of my work and some tutorials at:<br>

<a href="http://www.johnhpanos.com/">http://www.johnhpanos.com/</a></p>

<p>Marco, You don't yet understand. A stitched image looks exactly the same as a single image if it covers the same angle of view and is rendered in rectilinear projection. The individual images will be warped to enable them to align them accurately with each other, but the final image will not have a warped appearance. You only get warped effects when you use cylindrical and equirectangular projections for the stitched image (commonly used for extreme angles of view up to 360 degrees). As you extend the field of view to angles greater than about 100 degrees, then you begin to see increasing stretching effects at the edges in a rectilinear projection. However, this stretching is no worse than you would get with an equivalent standard lens that covered the same view.</p>

<p>You might be interested to see this architectural panorama I stitched a while back from 21 images from a Canon 40D + standard 50mm f/1.8 lens (3 rows of 7 portrait images):<br>

<a href="http://www.johnhpanos.com/wimpole2-large.jpg">http://www.johnhpanos.com/wimpole2-large.jpg</a><br>

The image at the above link is a half size copy (5MB). The full size image (15800x6000) prints at 52"x20" at 300ppi. For the stitching, I used PTGui Pro.</p>

 

<p><em>".... at the end of stitching process, the resulting image will be wrapped anyway , and I hate this effect, expecialy in architectures</em>."<br>

If you mean "warped", the stitched image should have the same general appearance as a single shot if the stitching is done correctly. Straight line features such as edges of walls and roof lines should be straighter, since any barrel and pin cushion distortion will be corrected.</p>

 

<p>The best stitchers work by assembling the images on a virtual spherical surface, aiming to reproduce the exact view seen from the original camera position. For output, any view can be selected in a variety of projections (similar to map projections of the earth). Thus, you have the option to select a flat (rectilinear) projection for modest angles of view up to around 110 degrees, or cylindrical and equirectangular projections for views that extend up to the full 360 degrees. <br>

Automatic stitchers are fine when things go right, but may not offer adequate facilities for manual intervention when images simply refuse to stitch properly. Hugin (Open Source freeware) and PTGui offer the most flexibility in this respect. For an automatic stitcher, the free Microsoft ICE stitcher is very capable and has a good choice of output file formats, including PSD layered. It can be downloaded from:<br>

<a href="http://research.microsoft.com/en-us/um/redmond/groups/ivm/ice/">http://research.microsoft.com/en-us/um/redmond/groups/ivm/ice/</a></p>

 

<p>Yes, Microsoft ICE is likely to give you a much better stitch. You might consider investing in a fisheye lens such as the Samyang 8mm fisheye (also sold under various brand names such as Polar, Falcon, Rokinon, Vivitar etc). With that, you can cover the entire 360x180 view in as few as 6 shots. You would need to use a stitcher that can handle fisheye lenses, but Hugin is also free and can do the job.</p>

<p>Zach, Entrance pupil and nodal point are not the same thing. In some lenses, these points are separated by tens of cm. Just browse this table of lens parameters for example:<br>

<a href="http://www.swissarmyfork.com/lens_table_1.htm">http://www.swissarmyfork.com/lens_table_1.htm</a><br>

It is the entrance pupil location that is the correct point about which to rotate the camera to avoid parallax. All the common methods of finding the no parallax point actually find the position of the entrance pupil rather than either of the two nodal points. The fact that the entrance pupil can be seen simply by looking into the lens makes it easy to find the no parallax point for a single lens reflex camera. See:<br>

<a href="http://www.johnhpanos.com/epcalib.htm">http://www.johnhpanos.com/epcalib.htm</a></p>

<p> </p>

<p>While PTGui can accept RAW files as input, the images get converted with DCRAW and any adjustments previously made in ACR are not actioned. Hence, corrections for chromatic aberration in particular are not possible. The stitched image in tiff format can be opened for processing in ACR.</p>

<p>The histogram feature is the same in CS5 as in CS4. The grey level used for the histogram is 220 and is perfectly visible on my calibrated monitor. Possibly your monitor needs adjustment.</p>

<p>Actually, the correct point to rotate the camera about to eliminate parallax effects is the entrance pupil of the lens, not the front nodal point. This is not an academic point; the two points can be separated by tens of cm in some lenses. In practice, the usual setup procedures recommended for finding the "nodal point" or no-parallax point (NPP) actually find the entance pupil. See <a href="http://www.janrik.net/PanoPostings/NoParallaxPoint/TheoryOfTheNoParallaxPoint.pdf">http://www.janrik.net/PanoPostings/NoParallaxPoint/TheoryOfTheNoParallaxPoint.pdf</a> .<br>

I have used PTGui for ten years and have not found anything better, being able to stitch images from extreme wide angle fisheye lenses to ordinary rectilinear lenses. There are many other stitching programs that can produce excellent results too, of course, but often with more limited control and flexibility. Examples of stitching done with PTGui can be seen on my web pages at <a href="http://www.johnhpanos.com">http://www.johnhpanos.com</a> .</p>

<p>I imagine the issue here is one of how much compression is being applied when saving to JPEG format. You should be using a lossless format such as TIFF and only convert (when necessary) to JPEG when you're sure the image manipulation is complete.</p>

<p>Robert K wrote: <em>Fixing pincushions and barrels is more challenging. How well does PTGui handle them?"</em><br>

PTGui and Hugin can correct lens distortions very well - even the extreme distortion of fisheye lenses. The correction should be similar to PTLens. As I acknowldeged in my earlier post, I did clone the blank corners manually. </p>

 

<p>An accurate correction can be performed using a spherical panorama stitching program, such as PTGui or the free Hugin. I used PTGui and cloned the blank corners.</p><div></div>

<p>It's working ok for me on a Wndows 7 system. There's a forum "hugin-ptx" on Google Groups, and this thread may be of help: <a href="http://tinyurl.com/3ys5oj8">http://tinyurl.com/3ys5oj8</a> .</p>