You are not logged in.

> The forum rules have been updated. Please take a moment to read them.


#1 2013-01-09 03:43:06

PanoPaco
New member
Registered: 2013-01-09
Posts: 1

Rendered panorama using multi-band blending is not sharp

APP has been for years my favorite piece of image processing software. I was very excited to try out the 3.0 release and re-do some of my old panoramas taking advantage of the new features. However, I am hitting a snag. So far out of a handful of different panoramas, I find the final renders produced by 3.0 are quite noticeably blurry. Though I imagine there is some setting I am not using properly, after trying a few things it seems to me there may be a more general issue with the rendering of panoramas using only multiband blending.

Here is the setup:

APP 2.0.9, Linux 64-bit, registered
Multi-core enabled, GPU rendering *disabled*

APP 3.0.1, Linux 64-bit, registred
Multi-core enabled, GPU rendering *disabled*

Panorama to be blended contains 83 photos. Panorama detection, alignment, projection, and cropping all done on APP 2.0.9, saved as a .pano file

Rendering on 2.0.9 using bilinear interpolation and multi-band blending yields the first attached image (crop of a small section). Notice the result is sharp througout. The second (middle) attached image shows the result of rendering in 2.0.9 using simple linear (not multi-band) blending. A bit blurrier than multi-band but still pretty good, and intended to show how much blur one would expect from camera shake or slight mis-alignment.

Loading the .pano and rendering on 3.0.1 using multi-band blending (no cutting, no anti-ghost, no diamon weighting) yields the third image. Notice it's blurry throughout (and this problem occurs for the entire panorama, not just this crop region). I used the default settings, and did not change in any way the projection, cropping, or any other panorama setting from the .pano generated by 2.0.9

Perhaps I'm missing something on how the multi-band blending is to be set up, but I can not seem to produce sharp renders after having tweaked the multi-band rendering parameters (which is basically only the level slider) multiple times. Furthermore, the problem occurs as well on the Windows 64-bit version, and I had observed the same issue with versions as early as APP 2.5.0 (which is why I've kept using 2.0.9).

From the rendered result, and the way point lights are being rendered, it seems to me there may be a problem with the warping stage of the rendering pipeline in 2.5 and onwards. Notice the point lights do not align at all, and this happens throughout the entire panorama in the same curious pattern. Since the panorama was aligned and cropped in 2.0.9, the image alignment stage is not the issue. Also, since the simple linear-blend from 2.0.9 is still noticeably sharper than the render from 3.0.1 (notice especially said point lights and the satellite dishes on the building) I am further inclined to believe it is not a blending problem in 3.0.1, but rather an actual increase in alignment error before blending occurs.

Notice that this problem would not be visible for panoramas rendered using anti-ghost, or with cuts selecting regions from individual images to blend onto the final render. However, due to the nature of my panorama and the source exposures, I do really need a multi-band blend to get the final result I'd like to obtain.

I am eager to hear tour thoughts on this. Look forward to it! thanks for the continous improvement to APP, and if you can suggest a way to deal with this problem I am certainly moving on to 3.0.1. Meanwhile, old, trusty 2.0.9 is fighting it out like a champ. Thanks!

P.S. Forgot to point out: I get the same blurry results if the entire workflow (panorama detection, alignment, cropping, adjustment, etc.) is done in 3.0.1. So it's not a problem arising from importing a panorama from 2.0.9.


Uploaded Images

Last edited by PanoPaco (2013-01-09 05:23:57)

Offline

 

#2 2013-01-09 09:39:04

ThomasV
Member
Registered: 2012-08-27
Posts: 246

Re: Rendered panorama using multi-band blending is not sharp

Hello,

Thanks for that. I think there is a lack of information on the changes between 2.0.9 and 3.0. Indeed in the 3.0 version, there are more flexibility on rendering settings.

Your first picture:
Version 2.0.9. Multi-band.
It implies use of anti-ghost, and therefore the misaligned objects are corrected.

Your second picture:
Version 2.0.9. Linear.
It implies diamond blending, so the image is a little blurry but not too much.

Your third picture:
Version 3.0.1. Multi-band, no anti-ghost, no diamond.
So, you get the worst result you can have on this panorama.
- Add anti-ghost, you should achieve the same result as your first pic
- Add diamond, and set linear interpolator, you should achieve the same result as your second pic.

Hope it helps.
Thomas

Offline

 

Board footer

Powered by PunBB
© Copyright 2002–2005 Rickard Andersson