HDR alignment problem - Trees

[DanielS]

Hello, I am shooting landscape panoramas (D800, 303SPH head, Nikon 16mm fisheye) and am having some issues with foliage blowing in the wind and not aligning well in PTGU between HDR exposures. 

It's a problem because the shift is not only between the exposures, but also between the adjacent images.

Any ideas?

Also, I am having problems with PTGui recognising skies and correctly stitching them when there are very few identifiable features, but I think Align to Grid will be the solution to this, and I'll have to set up some kind of template.

Cheers,

Dan

[Henrik]

Process the HDR sets first and then stitch, though you will still have the movements between different sets, if its really windy, in that case try to use the masking tool in PTGui

 
Henrik Tived

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[PTGui] HDR alignment problem - Trees

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[Luc Villeneuve]

Or find your best exposed shot, develop your raw file as is, and 2 other times at +2 and -2. Then do your HDR. At least, your image won't blur between shots.

I used this technique on this image. It's a 32 shots of a sailship, the Kruzenshtein. As you can image, a ship on a river is not the most stable subject. Here is a link to one of the images I did on that morning...

http://www.360-image.com/360/kruzenshtein/poupe/

Luc

[UtahBob]

On Tuesday, October 9, 2012 8:03:04 PM UTC-4, tived wrote:

Process the HDR sets first and then stitch, though you will still have the movements between different sets, if its really windy, in that case try to use the masking tool in PTGui

I've gone back through all the posts lately and settled on a workflow that I'm kind of happy with:

- use photomatix to merge the tif brackets (processed raw to clean up my sensor dirt and ca) to an hdr (no tonemap or fusion)

- load the hdr images into PTGui

- fix up ugly stuff with masking

- set up tonemap (optional unless you want tif output)

- stitch and then blend and use smartblend if the output is less than ~ 500 mp (I get corruption with anything greater)

- output hdr radiance pano and tonemap tif if desired

- fix up hdr radiance pano in photoshop if required

- load hdr radiance pano into photomatix

- tone in photomatix for final output

- if spherical bring back into PTGui to create qtvr

Other than being a long process, I think it works ok.  I like Luc method also unless you need more range.

Bob

[Erik Krause]

Am 10.10.2012 01:37, schrieb DanielS:
> Hello, I am shooting landscape panoramas (D800, 303SPH head, Nikon 16mm
> fisheye) and am having some issues with foliage blowing in the wind and
> not aligning well in PTGU between HDR exposures.

As Bob outlined already, Photoshop CS6 and photomatix do a very good job
removing ghosts while merging to HDR.

> It's a problem because the shift is not only between the exposures, but
> also between the adjacent images.

This has been a problem since panoramas are stitched. There are several
solutions: you can do manual masking in PTGui, you can edit the masks
after stitching (f.e. in photoshop) if you save "Blended and layers" in
PTGui, or you can use an alternative blender which is content aware. The
best one is certainly photoshop autoblend (available since CS3) or as a
PTGui plugin: smartblend (which is old and limited). For a comparison
see here:
http://www.panoramas.dk/panorama/CS3-autoblending.html

> Also, I am having problems with PTGui recognising skies and correctly
> stitching them when there are very few identifiable features, but I
> think Align to Grid will be the solution to this, and I'll have to set
> up some kind of template.

Since you use a 16mm fisheye on a full frame sensor simply don't shoot
90� up for zenith, but f.e. 70� or 80�. This will cover enough of the
horizon to give you some automatic control points and (hopefully :-)
cover the zenith hole. You can try out the angle in PTGui Pano Editor if
you move around the zenith shot manually, then read the Pitch value on
Image Parameters tab. Perhaps you need to set Roll to 0 before on Image
Parameters tab to get meaningful values.

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

[SunDance]

Luc,

 

Could you explain this procedure in more detail, please? Precisely HOW do you develop your RAW files this way?  Please advise.  (Details, details, details...)  Thanks.

 

BTW, your Kruzenshtein image is OUTSTANDING!

[Erik Krause]

Am 11.10.2012 18:59, schrieb SunDance:
> Could you explain this procedure in more detail, please? Precisely HOW
> do you develop your RAW files this way? Please advise. (Details,
> details, details...) Thanks.

There isn't more to it than Luc already wrote. You use the Exposure
slider in your raw converter, slide it to -2 and save, slide it to 0 and
save and slide it to +2 and save. This way you get 3 virtually bracketed
images which you can use to merge to HDR and tonemap. It can be debated
whether this is overkill, since the whole dynamic range can be extracted
into a single 16 bit TIFF...

[Matthew Ward]

On 11 Oct 2012, at 19:19, Erik Krause wrote:

 It can be debated whether this is overkill, since the whole dynamic range can be extracted into a single 16 bit TIFF...

It is not overkill, it is pointless. All Raw file converters that I am aware of will allow you to reduce the contrast to the point that you are displaying the entire tonal range contained within a Raw file. It is a very long winded way of tone mapping Raw files. 

Best

Matthew

[Erik Krause]

Am 12.10.2012 09:24, schrieb Matthew Ward:
>> It can be debated whether this is overkill, since the whole dynamic
>> range can be extracted into a single 16 bit TIFF...
>
> It is not overkill, it is pointless

Well, I'm no fan of virtual bracketing either and I'd never do it for a
whole panorama. However, there are occasions where it helps. Sometimes
handheld brackets won't align, not even if you use sophisticated
procedures like outlined on
http://wiki.panotools.org/Batch_merge_handheld_images
Or one image of a bracketed sequence is blurry due to camera shake.

In this cases I try to create an artificial bracket, most of the time
from the next darker image (no highlights clipped and hopefully sharper
due to shorter exposure). This way I can use the same workflow as for
the adjacent images and hence get the same tonality, which wouldn't be
the case if I use a flat contrast TIFF instead.

[Luc Villeneuve]

May I add another circumstance where virtual bracketing can help? Action shot. There is no way to produce this kind of image without virtual bracketing...

www.360-image.com/360/PPOC/06-rbci/q08_luc_villeneuve_07_12_006_74.html

[Erik Krause]

Am 12.10.2012 14:38, schrieb Luc Villeneuve:
> May I add another circumstance where virtual bracketing can help?
> Action shot. There is no way to produce this kind of image without
> virtual bracketing...

Well, if the whole panorama is not physically bracketed it should be
enough to extract the complete DR from the raw, like Matthew pointed
out. But if it is shot bracketed and you have single frames containing
action it is indeed helpful to do virtual bracketing on this frames.

[gravityimage]

Luc, would you mind explaining briefly how you virtual bracketed tis sample panorama? Did you shoot raw with one exposure in each direction? How many directions? I have a problem with motion in dar scenes like this, and I don't see a lot of the noise that I expected from high ISO.

Bill

[Roger D Williams]

Wow, Erik, another great suggestion. You are the master! I have needed this and kick myself for not thinking of it!

Roger W

Sent from my iPad

[Henrik]

Luc, very nice image

Henrik

Sent from my iPhone

[Henrik]

Erik,

Thanks that's a very good solution, for a very common problem.

Thanks for always providing this community with so much help

Henrik

Sent from my iPhone

[matthew ward]

Hi

you are recommending taking the luminance information contained in the RAW file, splitting it into 3 seperate low dynamic range files, sticking the 3 files back together then tone mapping them.

I am suggesting you could try tone mapping the RAW file with the sliders in your raw processor. (With Photoshop CS6 you use the same sliders)

You cannot increase the dynamic range/luminance information of the scene by virtual bracketting and as you say, often it is impossible to bracket.

Best

Matthew Ward

[Ken Warner]

Agreed. When raw converters were not so good, pseudo-hdr exposure fusion could help. Now with, for example Lightroom, what's the point? A good raw converter can produce even better results.

On 10/13/2012 6:07 AM, matthew ward wrote:
> Hi
> you are recommending taking the luminance information contained in the RAW file, splitting it into 3 seperate low dynamic range files, sticking the 3 files back together then tone mapping them.
> I am suggesting you could try tone mapping the RAW file with the sliders in your raw processor. (With Photoshop CS6 you use the same sliders)
> You cannot increase the dynamic range/luminance information of the scene by virtual bracketting and as you say, often it is impossible to bracket.
> Best
> Matthew Ward
>
>

> ________________________________

[Luc Villeneuve]

I use Enfuse for most of my work but again, sometimes even the best HDR workflow cannot do the job. The shot from the RedBull Crashed Ice I posted is a good example. The competitors run fast!

There is other instances where even the slightest movement can ruin a shot. As an example, a few days ago, I shot the tall ship Kruzenshtein was docked in Quebec City (32 images). The wind in the ropes were somewhat unnoticeable until I merged the HDR. I also knew that the flags could not be sharp. That's why I used the pseudo HDR. My point is that you have to build a workflow according to the scene.

Here is the final shot of the Kruz...

http://www.360-image.com/360/kruzenshtein/poupe/

Luc

[renevg]

Hi Erik,
I suppose when you use the next bracketed image, you use a different range of exposure values? That is; if you use the darker image of 2 EV underexposed raw file, you develop it to 0EV difference, +2EV and +4EV overexposed, to get in line with the other bracketed images? is that how you do it?

Op vrijdag 12 oktober 2012 14:20:11 UTC+2 schreef Erik Krause het volgende:

[Erik Krause]

Am 20.10.2012 15:24, schrieb renevg:
> I suppose when you use the next bracketed image, you use a different
> range of exposure values? That is; if you use the darker image of 2 EV
> underexposed raw file, you develop it to 0EV difference, +2EV and +4EV
> overexposed, to get in line with the other bracketed images? is that how
> you do it?

More or less. I never used it to replace all of the bracketed series. If
I bracket -2, 0, +2 EV sometimes the hand held +2 EV nadir shot is
blurred due to camera shake. In this case I use the 0 EV raw image, pull
the exposure slider to +2 and convert. This replaces the +2 shot nicely.