Blurry areas caused by changing light conditions - how do you handle this?

[ErnestoP]

I like panoramas where the sky is not all blue or all cloudy because it looks more interesting. But this sometimes causes difficulties when stitching all together because the moving clouds also change the lighting conditions of the ground. The result are blurry spots.

I am fighting against by masking with the green pencil and/or trying to equalize the brightness and contrast of neighbour-images in the RAW-converter. This is a very time consuming process - especially for HDR-panoramas with hundreds of photos.

Someone knows a faster way to handle this?

Here you can find an example for the lighting conditions what I mean: https://www.flickr.com/photos/photo-pie/29723939574/

Thank you very much in advance!

Ernst

[ekbmuts]

Ernst,  I have had similar problems. My solution was to get a fisheye lens and shoot the zenith first.  Even with 7 exposures for an HDR, that at least got the sky in the can. And as the lens took in the entire sky and reference points at the perimeter of the panorama (such as trees), I didn't need to use the sky in any other images and could just mask it out.

Shadows and hotspots on the ground and other objects is another matter entirely.  My suggestion would be to wait until the lighting was approximately the same as the last batch of shots and then shoot your bracket, rotate and wait for similar conditions and then repeat.

As far as there being methods to eliminate this issue within the program using masking and the like, I have not investigated that.  I doubt that any such method would give you a perfect fix however, even if you spend hours in Photoshop painstakingly handling each exposure.

Jon

[ErnestoP]

Thank you Jon
This is, what I do for "normal" panoramas. But I need a high resolution panorama. Therefore a lot of time passes between the first photo of the first row until the last photo of the last row. Where there was no sun, there may be sun when I take the photo in the next row. This is a very difficult job for PTGui to handle.
Masking helps in some situations but not always and it is not predictable (at least to me). I already tried different things to takeover control:
First I let PTGui handle the job for Tonemapping/Fusion - I found a lot of blurry areas.

Next I tried to stitch the panorama only with the photos of normal exposure (EV 0) - the same spots where blurry. -> It's not because of using HDR.
A bad NodalPoint is not the issue - the object is far away. On the camera there was all set to manually and every single picture has excellent sharpness. I am sure, it's the difference of brightness and contrast between the different rows.

Then I exported to PSB-File with layers (262 layers of 600 Megapixels!! -> I nearly found the limits of my PC). This way I could mask the blurry areas. But as the content of the layers is not tonemapped, I cannot get the same contrast as I need to do a perfect job.

Next I made tonemapped pictures with my HDR-programm and then I stitched with PTGui - the result was a little bit better. And I have the possibility to repair the bad areas with Photoshop and the equivalent tonemapped photo. But the tonemapped photos are not warped and do not fit with the panorama. Photoshop does align but not so perfect.

Now I am still searching for a better way to get an overall sharp panorama.
Many thanks for any suggestion!

Ernst

[John Houghton]

On Wednesday, October 19, 2016 at 7:01:52 AM UTC+1, ErnestoP wrote:

Next I made tonemapped pictures with my HDR-programm and then I stitched with PTGui - the result was a little bit better. And I have the possibility to repair the bad areas with Photoshop and the equivalent tonemapped photo. But the tonemapped photos are not warped and do not fit with the panorama. Photoshop does align but not so perfect.

You can output selected warped individual images for repairing bad areas so that they exactly fit the panorama.  I frequently do that for repairing stitches of handheld panoramas.

 

Now I am still searching for a better way to get an overall sharp panorama.
Many thanks for any suggestion!

The only solutions to the problem of matching rows seem to be the use of either multiple cameras or a camera with a wider angle of view.  How high does the resolution of the final panorama need to be?  What is the panorama to be used for?

John

 

[ErnestoP]

I think, the output of warped individual images will be the solution. I'll re-read the documentation which output settings I need.

The panorama will be used for an exhibition (a big poster of 4 DIN-A0 pages) of the local chronical team. And for some time maybe (if the commune has enough space on their web server) it will be online on the chronical homepage.

You can imagine, that every visitor will look for his own home and will be disappointed if just his home is blurry.

Many thanks!!

[Erik Krause]

Am 19.10.2016 um 16:41 schrieb ErnestoP:
> You can imagine, that every visitor will look for his own home and will be
> disappointed if just his home is blurry.

What you call blurry is actually reduced contrast. At least that's what
I experience with lighting changes due to moving clouds. Sometimes it
helps to use a different blender. I much prefer photoshop Auto Blend
Layers, which often does far better than the PTGui internal one. Create
as Blended and Layers to a photoshop document to use this.

The only drawback is, that photoshop does neither respect zenith, nadir
nor the 360° seam. The work around is to keep seams well away from
zenith and nadir and blend a 360° panorama twice, one version as is, one
shifted half width. The ShiftHalfWidth photoshop script by Eric Geerds
is inevitable in this case.

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

[ErnestoP]

Hi Erik

(Probably it would be easier to speak in german, but let's continue in english in this forum)

I am not sure if it is only reduced contrast. Because the result is much worse than my worst photo of the "blurry" area.

But - Yes, you are right - that's what I am doing now:

First I have done tonemapping with my HDR-program. Then I have created the pano with PTGui into a PSB-file with all layers in separate files. It's faster only to choose the specific file for retouching an area than to have all 131 layers at the same time loaded in Photoshop.

It seems that I am coming to an end now. Mountains and forest already are finished. Now I have to retouch the critical area: the village, where bad masking leads to easily visible ghost pictures.

I  already have written a script for editing 360° panos with Photoshop but it's a little bit unhandy - so I will look for Eric Geerds script. Surely it's better than mine.

Thank you all again!

Ernst

[ekbmuts]

Ernst, Now I'm curious because that sounds like a HUGE panorama!  What camera and, more importantly, what lens are you using?

When you've got the final panorama completed and posted somewhere, post a link to it, would you?

Jon

[PTGui Support]

Hi Ernst,

The problem with stitching already tone mapped images is the fact that
the tone mapper will create each image with different adjustments. E.g.
if the image has little contrast, the tone mapper might decide to
increase the contrast a bit, more than the next image. So you'll end up
with widely different exposures which are difficult for PTGui's blender
to equalize.

Kind regards,

New House Internet Services BV
Joost Nieuwenhuijse

-----------------------------------------------
PTGui - Photo Stitching Software

www.ptgui.com
For support see: http://www.ptgui.com/faq/
-----------------------------------------------

> --
> Many people are reading this forum via email and get every post
> delivered to their inbox. To limit the amount of data please do not add
> attachments or images to your posts; instead upload your files at a file
> sharing site (for example http://sendspace.com// ) and include a link in
> your message.
> ---
> You received this message because you are subscribed to the Google
> Groups "PTGui Support" group.
> To unsubscribe from this group and stop receiving emails from it, send
> an email to ptgui+un...@googlegroups.com
> <mailto:ptgui+un...@googlegroups.com>.
> To post to this group, send email to pt...@googlegroups.com
> <mailto:pt...@googlegroups.com>.
> Visit this group at https://groups.google.com/group/ptgui.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/ptgui/1ed6776d-4769-423f-a5ab-2c4895e7dd10%40googlegroups.com
> <https://groups.google.com/d/msgid/ptgui/1ed6776d-4769-423f-a5ab-2c4895e7dd10%40googlegroups.com?utm_medium=email&utm_source=footer>.
> For more options, visit https://groups.google.com/d/optout.

[ErnestoP]

Hi John

I am aware of the different adjustments by doing so. But I do not have all the options that I would have with a normal sized panorama (and every experiment lasts longer).

Another intention was to make a HDR-file with PTGui and tonemap with Oloneo. But Oloneo crashes because of the big size of the file. I had a 32bit version of Photomatix which I did not upgrade to 64 bit. I don't know if this program could handle such a big file. Oloneo is a 64bit program and can't. Apart from that I cannot retouch the HDR file using the original exposures. Retouching the already tonemapped image (created by PTGui itself) I would have the same problem.

Using only one exposure series ist not possible because the contrasts are too high - even for the RAW converter. Therefore my only idea how I can handle this, was to first create tonemapped versions of every shot and take these as input for PTGui.

PTGui does a good job but it is not made for automatic retouching. The dull areas are nearly the same as if I make the panorama only with one exposure series. This is why I am so sure, that the reason for all of my problems only is the change of lighting conditions from taking one row to the next row. Where there was shadow first, in the second row there came the sun out.

I would have some more ideas but I think it's faster to continue the way that I already began.

If I have time I will experiment taking only one of the critical parts of the big panorama. I want to check the output of Helicon Focus if I give him the already warped and tonemapped pictures as input. It does a completely different job but maybe that it can do something useful. Another question is - does Helicon Focus crash with the big files?

I also thought to blend with Photoshop but it's so slow in comparison to PTGui - the same with smartblend.

Thanks again!

Ernst

[ErnestoP]

Hi Jon

It's really a huge panorama - not so far away from a Gigapixel-Pano. My camera is a Sony A77ii (24Mpix). As lens I used my Sigma 105mm/F2.8 Macro because it's my sharpest lens with focal length of round about 100mm. I only used a normal tripod without Nodal Adapter - that's not necessary because of the distance of much more than 1000m.

The primary intention is to make a big print as eye catcher. But if I can get enough webspace without costs for some time, I also will show the panorama on the web.

If you are interested in my work, you can find some of my panoramas that I made for the chronical homepage of my home village: http://ernst.pisch.at/Bildchronik/dorfansichten.html

(Sorry it's only in german language because it was intended only for the local people.)

Thank you for your interest!

[Erik Krause]

Am 19.10.2016 um 23:07 schrieb ErnestoP:

> I am not sure if it is only reduced contrast. Because the result is much
> worse than my worst photo of the "blurry" area.

Yes, of course. Contrast is reduced actively by the blender, if the
source images have a different brightness. This is by nature of the used
multi resolution spline blending.

Brightness differences are inevitable if you do tonemapping before
stitching. The tonemapper does not know about the other images and
"exposes" each that it looks best. Sometimes it helps to optimize for
exposure (full) on Exposure/HDR tab.

> Now I have to retouch the critical area: the village, where bad
> masking leads to easily visible ghost pictures.

And there's where you could benefit from Auto Blend Layers. See a
comparison here: http://www.panoramas.dk/panorama/CS3-autoblending.html

[ErnestoP]

Hi Erik

I like Photoshops "Auto Blend Layers" but I find it useless if there are more than only a few layers. I have a fast hardware ( 8 core Xeon 3.5Ghz, 64GB RAM, 512GB PCIe SSD + 3TB SATA HD, NVIDIA Quadro M4000) - PTGui stitches the 131 photos (each of them 24Mpix) in less than 2 minutes.

All works fast but Auto Blend Layers is terribly slow with many layers. CPU-load is only at 15%, the graphic-card does nothing and there is no disk-I/O. RAM usage is only about 37%. Photoshop could use much more if needed (and it does successfully for other jobs). The progess bar starts quick up to nearly 10% and stops. Then it takes 5 to 10 minutes or more until I can observe one pixel of progress :-(

The same happens with focus stacking. Helicon Focus does the job in less than a minute but Photoshop needs hours.

Do you have better experiences with Auto Blend Layers? What I am doing wrong? (I am working with the most recent version of Photoshop CC)

[ErnestoP]

Thank you so much, Erik

to mention the use of Photoshops "Auto Blend Layers". After hours of frustration because the progress bar did not grow, I've got an error message. Photoshop ran out of some space. This forced me to look for the settings of Photoshop. There I found cache settings. Now, after setting these to bigger values, Auto Blend Layers runs fast :-))

... and it does a wonderful job!

The conclusion: You have to do something big if you want to learn new things. Many thanks to all of you - I've learnt a lot creating my first 600+Megapixel Panorama

Am Donnerstag, 20. Oktober 2016 17:20:02 UTC+2 schrieb Erik Krause:

[ErnestoP]

Hi ekbmuts

Here you can find the (final?) panorama:

https://www.flickr.com/photos/photo-pie/29723939574/in/dateposted-public/

This is only ~1/3 of the original size and to my taste a little bit too "HDRish". But it is not for my own usage and the persons that I asked, prefer this version.

Ernst

Am Mittwoch, 19. Oktober 2016 23:15:18 UTC+2 schrieb ekbmuts: