Re: [PTGui] Stitching Aerial 360 Pano's

[Erik Krause]

Am 26.03.2014 22:09, schrieb Adam Pass:
> Either way what I have been doing is stitching the images using
> Photomerge in Photoshop which has been dealing with the images quite
> perfectly. The issue with photoshop is that is doesn't deal with the
> overlap. So my workaround has been to stitch in Photoshop and then crop
> that image down a dozen times or so and import those files into PTGUI to
> then stitch for a final product that can create a seamless 360 with perfect
> overlap. However crazy that may sound it has been working really well.

This is crazy indeed and surely not needed. Make your images available
for download somewhere together with the project file and we can have a
look. Most likely you don't give enough freedom to the optimizer or the
like.

Please do not add attachments to your posts; instead upload your files
at a file sharing site (for example http://ge.tt/ ) and include a link
in your message.

--
Erik Krause
http://www.erik-krause.de

[Adam Pass]

Hi Erik, 

Thanks for the quick reply. My apologies on the attachment. Here is a link to the images and project file. 

http://we.tl/G8eWJd0Fdh

Thanks, 

Adam 

[Erik Krause]

Am 26.03.2014 23:32, schrieb Adam Pass:
> http://we.tl/G8eWJd0Fdh

I had a brief look. Yes, there's a lot of parallax in the images, as was
to be expected. However, you can improve the result if you create more
control points (run Ctrl+Alt+G repeatedly or increase number in
Tools->Options->Control Point Generator) and use viewpoint correction
(assuming you have the pro version). There's a danger however: Some
buildings might not have totally vertical edges.

Other possibilities are edit seams using the mask option or use a
blender with seam optimization like f.e. smartblend or blend afterwards
with photoshop auto blend layers. The latter needs to be done twice with
the 360° seam in different positions. Then stitch the two versions
together in PTGui.
(A quicker way is to use http://www.pinlady.net/vr/#anchor5 and shift
one version of the layered PSD before autoblending, then shift back,
overlay both and mask the seam).

[Sunfunnel 360]

http://dronexpert.nl/product/dji-phantom-360-panorama-head-remote-complete/

[Adam Pass]

Thanks again Erik. I will have to spend some time experimenting with your suggestions. I have tried to generate more control points and it doesn't seem to have much of an effect. I don't have the pro version. What effect will viewpoint correction have on the stitch? Will it help line up the images more seamlessly? If so I will purchase the pro version. As far as the other possibilities, they seem to get more time consuming. When trying to produce 20 pano's this can be a problem. That's why my crazy work around has been so effective and efficient. It consistently produces the best results I have been able to produce. That brings me back to my original question and the attached file above. That photo is seamlessly merged in Photoshop. Using PTGUI what may be the best way to ready that image for a 360 pano with a seamless overlap. I shared my solution about cropping the image down and re stitching it and it works quite well. 

[Erik Krause]

Am 27.03.2014 02:30, schrieb Adam Pass:

> I will have to spend some time experimenting with your suggestions. I
> have tried to generate more control points and it doesn't seem to
> have much of an effect. I don't have the pro version. What effect
> will viewpoint correction have on the stitch?

Viewpoint correction is intended to correct images not taken from the
same viewpoint. However, as you see in
http://www.ptgui.com/examples/vptutorial.html this works perfectly only
for flat surfaces. But it can sometimes help stitching panoramas with
slightly varying viewpoint (at the expense of buildings leaning over a bit).

> Will it help line up the images more seamlessly? If so I will
> purchase the pro version. As far as the other possibilities, they
> seem to get more time consuming.

The big benefit of photomerge is the photoshop autoblend algorithm. It
calculates seams such that they go through regions with least details
which obviously hides errors best. PTGui doesn't do this, it places the
seam in the middle of the overlap. But it allows to use external
programs as a plugin. One of those is smartblend, which does a pretty
good seam optimization.

The other possibility is to use photoshop autoblend, which isn't only
better but also much faster than smartblend. You need to create a PSD or
PSB with individual layers only from PTGui, load it into photoshop,
duplicate it, use Eric Gerds "Shift half width" script (see link last
mail) on one of them. Then select all layers and choose "Auto blend
layers" from Edit menu on both. Flatten both and use "Shift half width"
on one of them agin, then Shift-Drag one from the layers palette on top
of the other, add a mask and mask the visible seam with a soft large
brush. All this takes usually 2 to 3 minutes and you can even automate
it recording an action.

I've done that on your un-altered project. Here's the downsized result:
http://ge.tt/3TonvAU1/v/0