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Johnytuono
08-23-2013, 06:38 PM
Hi
Just ordered my M1 and was wondering if anybody has a set of images I can practise my software technique on. Would like an 'easy' set that contains a Nadir obviously and a set that may present problems. I use Autopano Giga.
Thanks
John

hindenhaag
08-23-2013, 11:30 PM
Hi John,

http://ge.tt/5t2cubS

Heinz

John Houghton
08-24-2013, 07:08 AM
John, Here's another set for you to play with: http://ge.tt/8CUmeop/v/0?c

John

Johnytuono
08-24-2013, 08:14 AM
Thank you very much both of you.....will have a go with them.
Btw what is the .pts file for?
John

John Houghton
08-24-2013, 12:13 PM
The pts file is a PTGui Pro project file. The stitch was produced entirely with that project - no Photoshop tweaking applied. You may be able to import the project file as a PanoTools project, though there are some viewpoint images that Autopano Giga probably cannot handle which would need to be deleted.

John

hindenhaag
08-24-2013, 12:15 PM
It is the file of the "project". It saves everything you have done in PTGui. Masking lens settings etc etc. With the pics and the project file you can open the whole project and see the result. You can check the control points, Max Distance of CP etc.

Heinz

Johnytuono
08-25-2013, 06:53 AM
Ah I see thanks. Been watching various tutorials and can't understand why 2 Nadir shots are taken.....1 from straight down and the other slightly offset.....as both show either the tripod head or legs. Why not just take the -90 and then mask/edit the head out?
John

John Houghton
08-25-2013, 11:11 AM
Been watching various tutorials and can't understand why 2 Nadir shots are taken.....1 from straight down and the other slightly offset.....as both show either the tripod head or legs. Why not just take the -90 and then mask/edit the head out?
When you "mask/edit the head out", you have to replace the areas occupied by the head/tripod etc. with something. For the perfectionist, the answer is for that something to be what is actually obscured by the said head/tripod. That can only be captured by moving the tripod out of the way. You can then photograph the unobscured nadir area either from the side (to avoid shadows) or with the camera close to where it was when it was originally on the tripod (e.g. using a nadir adapter such as is available for Nodal Ninja heads). The nadir editing can then be carried out either during the stitching (using PTGui's viewpoint correction, for example) or manually in Photoshop - usually working with rectilinear views extracted from the equirectangular panorama image for convenience. The end result is then a perfect rendering of the entire 360x180 view, including the nadir area - however inconsequential that may happen to be. Cloning away the head/tripod using data from the surrounding area is often done when the floor/ground is characterless - such as gravel, grass, concrete - or when there is a repeating pattern of tiles or floorboards. Alas, this cloning is often carried out inexpertly leaving all-too-visible copies of obvious features. But the word is that this is completely unimportant as nobody looks at the nadir area anyway. Take your pick.
.
John

Johnytuono
08-25-2013, 12:44 PM
Thanks for that detailed explanation John. I have been trying to do this in Autopano using the images that Heinz allowed me to practise on but can't 'seem' to do it, is PTGui a better program for this?
Thanks
John

John Houghton
08-25-2013, 01:15 PM
John, I'm not an Autopano expert, but see this thread which goes some way to answering your query: http://www.hdrlabs.com/cgi-bin/forum/YaBB.pl?num=1306934786. PTGui can handle offset nadir images with aplomb, though it may require some manual input. There are a couple of tutorials describing how to do it:
.
http://www.ptgui.com/examples/vptutorial.html
http://www.johnhpanos.com/ptgvpt.htm
.
John

Johnytuono
08-27-2013, 10:19 AM
Hi
Been using a trial version of PTGui and find it much more user-friendly. Used Alpha masks on the patch shots in Photoshop and then added them in PTGui and the Nadir looked great!
One question though, in some of the images the bottom of the tripod is obviously visible....I'm assuming I mask these out.......but what about the shadows on the Nadir patch shot....do I mask that out beforehand using the Alpha mask or do I do it in PTGui. I did the Nadir patch shot mask in PS and the tripod ones (in each image) in PTGui.......did I do that right?
Thanks
John

John Houghton
08-27-2013, 10:52 AM
John, There's no difference between applying masking via an alpha channel using Photoshop and doing it in PTGui Pro. Both ways have the same end effect. It's generally best to mask out all instances of tripods and shadows appearing in the images. With care taken in the shooting, there shouldn't be any "holes" left after blending. Sometimes it can be advantageous to align the nadir patch image in PTGui but blend it into a stitch of all the other images using Photoshop. That way you can choose the precise route of the seam line to achieve a seamless effect when PTGui doesn't quite manage to do that for one reason or another. To do this, you output two stitched equirectangular images from PTGui: one containing only the nadir patch and one containing all the other images. These can be merged by generating cube faces or extracting matching recilinear views with various bits of software.

John

Johnytuono
08-30-2013, 03:44 PM
Heinz and John.......thanks for the images for practising on....i think I managed to work out the masking out of shadows and tripod and am pleased with the result. Just one thing on your set John, I loaded up your project file and noticed 4 ( I think) of the same image and that you had masked almost all the picture leaving just a very small segment of the kerbstone or a little bit of double yellow lines......what was the reasoning behind this please. I thought at first it was because of some shadow or something but when I masked out I didn't need to do this and the nadir looked perfect.
Thanks
John

John Houghton
08-31-2013, 07:46 AM
John, The four viewpoint nadirs were not really necessary, and in fact I did not use them when I originally stitched the images for my web site. The tripod shadow fell across four levels of steps, representing four separate planes. So in theory, four viewpoint corrections were necessary to patch them. So, as an exercise, I input the one viewpoint nadir shot four times and aligned each separately with the four steps and masked them accordingly. This, of course, worked ok but simpler patching is perfectly adequate as the shadow is quite small.

John

Johnytuono
08-31-2013, 08:53 AM
Ah I see your thinking......thanks for that John at least I'll have an idea what to do now if I ever come across a similar thing.
John