New engine, Blue skies....

[mountaintb]

New engine, Blue skies....

by mountaintb » Fri Feb 25, 2011 2:12 pm

High all,

Since the new version (alpha, beta, RC and final version), I have quite a few problems with my blue skies and the settings of the antighost :

Either I use the antighost at the -4 multiband setting and I reproduce the mosaïc in my sky or I set it at -2 or -3 and I have dirty zone in my skies.

Those shots are made all in manual (WB, exposure.....).

Have I got, before the render, to work on the level LDR, HDR ?

Thank you very much.


TB

[GURL]

by GURL » Fri Feb 25, 2011 10:59 pm

I presume there are 4 rows of 18 sources images?

Including some sources images and a capture of the Render window showing the settings could help...

[mountaintb]

by mountaintb » Fri Feb 25, 2011 11:31 pm

I will post it tomorrow.

TY

[mountaintb]

by mountaintb » Sat Feb 26, 2011 11:08 am

Here it is Georges :
- one of the 72 images, I have 3 rows of 24 as seen on the edit capture and the normal antighost renderring (I have tried most of the levels -2, -3....).

[mountaintb]

by mountaintb » Sat Feb 26, 2011 11:14 am

The photos comes from Nikon D700 300mm f4 nikkor at f13 (for less vignetting) and NN5 at limit of angle 3,75 degrees.

[mountaintb]

by mountaintb » Mon Feb 28, 2011 9:15 am

It seems I am not the only one so Have you got any comment ????

TY

[GURL]

by GURL » Mon Feb 28, 2011 11:03 am

Having vertical dark zones while no horizontal zone is visible is rather strange... In my opinion vignetting or any other exposure differences should produce horizontal dark zones, too.

I would use http://www.autopano.net/forum/t766-ftp-server to send this project and the corresponding source images to Kolor.

[AlexandreJ]

by AlexandreJ » Mon Feb 28, 2011 11:16 am

This case seems to suffer of vignetting a lot. Engine 2.0 nor engine 2.5 was not able to address this issue. To thread this case well, you probably need to decode the raw with vignetting correction. For sky smoothing ( if you have color differences ), the engine can cope with them.

[klausesser]

by klausesser » Mon Feb 28, 2011 2:08 pm

The photos comes from Nikon D700 300mm f4 nikkor at f13 (for less vignetting) and NN5 at limit of angle 3,75 degrees.

did you use Photomatix? There´s a misunderstandable box in the tonemap-settings which i clicked on some time ago which lead to vignetting-like results: "360° image"

best, Klaus

[mountaintb]

by mountaintb » Mon Feb 28, 2011 7:06 pm

The funny stuff about that vignetting is that : I always use the lens at the same sort of aperture f/13 to f/16 where vignetting is the less important. The other funny stuff is that I have a collection of 70 panos made with the 300mmm always at the same sort of aperture and in the same sort of light and sometimes I have nothing and sometimes I have that result.....

Thank you for your contribution.

[mountaintb]

by mountaintb » Mon Feb 28, 2011 7:08 pm

Oh and I am going to do again the profile of my lens with Lens Profile Creator.

[klausesser]

by klausesser » Mon Feb 28, 2011 7:44 pm

Oh and I am going to do again the profile of my lens with Lens Profile Creator.

Do you otherwise process your images in any way before stitching?

best, Klaus

[mountaintb]

by mountaintb » Tue Mar 01, 2011 11:04 am

Yes of course I use Nikon capture NX2 and I have tried any solution to get rid of any vignetting... But it does not change a lot. After that i thought it was due to a problem of overlapping with the NN5 (300mm is the maximum lens you can use (7,5 ° / 2).

[mountaintb]

by mountaintb » Tue Mar 01, 2011 11:21 am

I think I know : have a look to my layers window, it does not recognize the 300mm... so is the overlapping enough???

[klausesser]

by klausesser » Tue Mar 01, 2011 11:46 am

I think I know : have a look to my layers window, it does not recognize the 300mm... so is the overlapping enough???

You need at least 20% overlap - better 25% because of tolerances with a manual head. But too less overlap would result in bad CPs instead of vignetting.
Did you try images which are completely pure from the camera? without ANY pre-processing?

best, Klaus

[klausesser]

by klausesser » Tue Mar 01, 2011 11:48 am

Did you use color correction? That should solve the problem usually.

[klausesser]

by klausesser » Tue Mar 01, 2011 11:49 am

Can you show a rendered image? What we see is just a preview.

[GURL]

by GURL » Tue Mar 01, 2011 12:38 pm

I think I know : have a look to my layers window, it does not recognize the 300mm... so is the overlapping enough???

When placing cotrol point (detection) the focal length is ignored. CP are used to compute focal length (values displayed in the layers window.) A 300mm value instead of 200mm actual value should not be very armful: slightly distorted perspective only, I guess.

I have a strong reasons to believe this not being related to vignetting:
- with vignetting the top and bottm sides of sources images are darker than the left and right sides
- with vignetting the corners are the darker places.

My bet: the dark bands on your panos are too regular, vignetting is not the culprit !

You could stitch the same pano (of a part of it) using the 3 available blenders (None, Linear, Multiband) or use the Image mode tool to show an enlarged view of selected source images where the overlap is clearly visible.

[GURL]

by GURL » Tue Mar 01, 2011 12:46 pm

Overlap example, where 3 images are selected using Ctrl-Clicks:

Last edited by GURL on Tue Mar 01, 2011 12:47 pm, edited 1 time in total.

[mountaintb]

by mountaintb » Tue Mar 01, 2011 3:21 pm

here is the result :

[mountaintb]

by mountaintb » Tue Mar 01, 2011 3:22 pm

And that is at the normal antighost level (-4)

[mountaintb]

by mountaintb » Tue Mar 01, 2011 3:26 pm

And this an exemple of the overlap I use

[AlexandreJ]

by AlexandreJ » Tue Mar 01, 2011 3:42 pm

That's a typical vignetting case. It can be compensated by the blending when the overlapping is higher than this one ( around 20 % ). Vignetting is an issue that start to be important only during the last 20% ... So the overlapping zone has pixels of both images and all of these pixels have important vignetting power.

[mountaintb]

by mountaintb » Tue Mar 01, 2011 5:01 pm

so Alexandre what blending should I use???

[AlexandreJ]

by AlexandreJ » Tue Mar 01, 2011 5:06 pm

blender : multiband of course. But it won't compensate the vignetting in this case, because of the low overlapping.