stiched vertical Pano with hdr

[Michael Fontana]

The zuiko 21 works great, as it has a big angle, meanwhile keeping good contrast/resolution, and rather low distortion.

So here is a partial QTVR, made with it.

It's not perfect, I know, so some of the hardcore-stitchers - I'm a newbe - might add some critic and comments.
Reminder: The goal is to show art installations, covering walls and floors, better than singleshots can do.

 

[Ray West]

Hi Michael,

The chair is one of the best demonstrations I've come across, to show Moire pattern interference ;-)

It is a considerable improvement re. stitching, but I think the focus/sharpness of the image varies across the scene. However, if your final aim is for large flat surfaces, that may or may not be a problem. For a large flat surface, then I think a stepping method would be better than a camera rotating method for accuracy.

Best wishes,

Ray

 

[Michael Fontana]

Thanks, Ray
what do you mean by "stepping method would be better "?

As for the Moirée: the planar stitch has some 680 MB (16bit) therefore a small QT with 5 MB will have some losses.
I'm sure, one can reduce these, but I' ve to figure it out, yet. I haven't worked really on the image, but rather to get the stitch well done.

The images were RAWs, but no HDR, so there is plenty of headroom.

 

[Ray West]

Hi Michael,

I was not being critical of the chair, I know what causes the pattern, and it is bound to happen at some stage or other in digital images, to a greater or lesser extent, when displayed on any digital device.

By stepping, I mean that instead of rotating the camera with it being fixed in one position, which makes the edges of the subject further away than the centre, you step the camera over , thus the distance to the subject is substantially the same. It will work for a flat surface, but not for landscape - unless you count aerial photography for mapping (the landscape is then far enough away to be considered flat). I think with care, and depending on the subject, and time available, you would get good results simply by moving a normal tripod parallel to the subject. (I suppose it could be considered as a manual shift lens, but obviously the movement will be greater.) I suspect there is a technical term for what I described. ;-)

Best wishes,
Ray

 

[Klaus Esser]

The zuiko 21 works great, as it has a big angle, meanwhile keeping good contrast/resolution, and rather low distortion.

So here is a partial QTVR, made with it.

It's not perfect, I know, so some of the hardcore-stitchers - I'm a newbe - might add some critic and comments.
Reminder: The goal is to show art installations, covering walls and floors, better than singleshots can do.

Hey Michael!

very important to show installations or paintings in a room - simply everything which is very geometrical - is, to absolutely adjust your noadal-point-adapter! Saves a lot of work afterwards.

I would suggest to make spherical panos - you can easily extract parts of it later for planar-panos.
When you shoot cylindrical-panos, make symmetric rows - one horizontal. one up, one down.
1) the resolution is better and (more important)
2) the symmetry to stitch without greater distortions is better for the stitcher/blender.

best, Klaus

 

[Klaus Esser]

Hi Michael,

I was not being critical of the chair, I know what causes the pattern, and it is bound to happen at some stage or other in digital images, to a greater or lesser extent, when displayed on any digital device.

By stepping, I mean that instead of rotating the camera with it being fixed in one position, which makes the edges of the subject further away than the centre, you step the camera over , thus the distance to the subject is substantially the same. It will work for a flat surface, but not for landscape - unless you count aerial photography for mapping (the landscape is then far enough away to be considered flat). I think with care, and depending on the subject, and time available, you would get good results simply by moving a normal tripod parallel to the subject. (I suppose it could be considered as a manual shift lens, but obviously the movement will be greater.) I suspect there is a technical term for what I described. ;-)

Best wishes,
Ray

Hello Ray!

Moiree comes from the Chip. Regardless if you swing a camera around it´s npp or do a parallel-shift or a linear stitch (that´s the word) by moving a camera parallel to a plane.
Some chips/cameras produce moiree earlier some later - it´s the geometrical alignment/structure of the sensors on a chip.

If it ocours it´s sometimes easy to remove - so it is with the chair - and sometimes more complicated, as with clothes for example, by using special filters in postpro.

Doing stitches in a linear way is 1) VERY complicated - you have to calculate the exact mid-point for each movement to avoid EVERY perspective view and 2) it looks obviously artificial, unnatural.

look here for some examples of linear photographing and stitching (click at "Bild größer zeigen"):

http://www.tomasriehle.de/bilder.php?dir=fotografische_abwicklu&&pic=4

best, Klaus

 

[Bart_van_der_Wolf]

I was not being critical of the chair, I know what causes the pattern, and it is bound to happen at some stage or other in digital images, to a greater or lesser extent, when displayed on any digital device.

In this case it is caused by the resampling method used for zooming in the QT 'plugin'. It does demonstrate moire/aliasing 'nicely'. Avoiding it is possible, but probably too slow to be practical.

I suspect there is a technical term for what I described. ;-)

You described it well. I think it could be called stepping or tiling (from adding tiles). It works when there is essentially no foreground, because that would show parallax ghosts. Flat subjects shot with longer focal lengths work best.

Bart

 

[Klaus Esser]

Hi Bart!

"In this case it is caused by the resampling method used for zooming in the QT 'plugin'."

Exactly. I had a list of dividings which deminishes resampling artifacts in QT - i´ll look for it.
There are certain factors which minimizes it.

"Tiling", parallel-stitching at short distances - as inside rooms with art-installations - is nearly impossible.
I did some experiments. But for reproduction of a single picture by shifting only the digital back/camera it works well - as Michael did already. Here the lens is the limiting factor.

best, Klaus

 

[Bart_van_der_Wolf]

"Tiling", parallel-stitching at short distances - as inside rooms with art-installations - is nearly impossible.

Short distances make it hard, especially with short focal lengths. The reason is perspective and geometry.
Assuming the subject is flat (3D structures wll fail because the foreground will show parallax between the individual images) the main geometrical 'distortion' per image tile is the magnification difference between the center and the corners of a rectilinear (on a flat plane) projection.
To correct for that, one may need to convert (in the final projection) to a relatively long focal length if the original focal length was 'short'. Of course, capable software will be able to automagically figure this out, if enough control-points are supplied and offset is calculated correctly.

I did some experiments. But for reproduction of a single picture by shifting only the digital back/camera it works well - as Michael did already. Here the lens is the limiting factor.

Indeed, and the most important stitching parameter is a Horizontal or Vertical offset between the images. Once that is corrected, the remainder is for minor lens distortions. Anything with depth in it, needs to be shot from a single point.

Bart

 

[Klaus Esser]

Short distances make it hard, especially with short focal lengths. The reason is perspective and geometry.
Assuming the subject is flat (3D structures wll fail because the foreground will show parallax between the individual images) the main geometrical 'distortion' per image tile is the magnification difference between the center and the corners of a rectilinear (on a flat plane) projection.
To correct for that, one may need to convert (in the final projection) to a relatively long focal length if the original focal length was 'short'. Of course, capable software will be able to automagically figure this out, if enough control-points are supplied and offset is calculated correctly.



Indeed, and the most important stitching parameter is a Horizontal or Vertical offset between the images. Once that is corrected, the remainder is for minor lens distortions. Anything with depth in it, needs to be shot from a single point.

Bart

Hi Bart!

Did you ever shoot parallel stitches inside rooms? Could you show us some examples?

best, Klaus

 

[Ray West]

Hi Klaus,

Thanks for the link. I do not know if all the images were linear stitch examples, but it gives an unnatural distortion in many instances, although possibly geometrically accurate. It depends on the subject, and how the result is being presented or viewed, and the purpose. My intention in suggesting it was purely for flat surfaces - e.g. copying a large painting. If there is any depth to the image, you either have to be very selective in choosing the camera positions, and/or how you fudge the overlapping images. I have taken images of lengths of hedgerows, for example, linearly stitched, and trees in the background and clouds are duplicated, but for my purposes, it didn't matter, or a clone tool got the result good enough. I think for a room, with normal furniture or bookshelves, say, not bare walls, you would need a lens with a very narrow field of view, and take many images. For a room, where normally you would stand and look about you, then the spherical panoramic stitching will appear more natural. For more scientific purposes, then I think that linear stitching is required, at least with the current state of the art/affordability.

http://www.klausesser.de/VinKugelH.mov is very good, appears very natural, if you pan/rotate at the camera level, and somehow, I want to walk down the shop... However, if you look up or down, and then pan, the perspective looks unnatural. This is possibly related to the fact that you are not moving your head, which possibly switches in some sort of neural compensation for the real image orientation, and reality's larger size and so on and so forth.

Bath city council, it must have been ten or twelve years ago, took a number of images of their Georgian house fronts, and built them into the 'doom' virtual reality game engine. Builders/developers/architects, then merged in their proposed alterations, so that an impression of the changes could be obtained. Obviously the detail was not as we would expect now, but afaik, the images were all captured hand held, and linearly stitched.

Now, just for fun, get a couple of dozen cheap point and shoots, mount them on a spherical array, fire them all at the same time (a bit like a time slicing array) Correct the results in software.

Best wishes,

Ray

 

[Klaus Esser]

Hi Ray!

"Now, just for fun, get a couple of dozen cheap point and shoots, mount them on a spherical array, fire them all at the same time (a bit like a time slicing array) Correct the results in software. "

There´s a guy in Texas, who has build an "Event-Cam" (http://www.kaidan.com/EventCam.html) of a bunch of compact-digital cameras as a circle-arrangement and can fire them simultanously as a one-shot-pano. Funny!
There were several constructions to make it spherical too. I know a construction with 3 Nikons with fisheyes i a circle and each camera-lens was tilted in a calculated angle.
You can make a one-shot spherical VR with it : http://www.agnos.com/catalogo.htm?v...00000643466948470344&v_cod_art_sche=MROTATORR

best, Klaus

 

[Michael Fontana]

okay, I optimised pretty carefully my set-up for the zuiko 21 - single-row- 5 shots - and it looks pretty good. The aequivalent on FF would be about 11 mm (landscape orientation, and 14 mm, in height. The final file has 3.5 x the size of FF. Just web-screenie's, the tiffs look better:

and some 100% crops:

This copy of the zuiko 21 has a weeker upper sie - in landscape orientation; so I better do make 6 shots instead of 5, and cut it of, later. But I like that set-up, its fast and easy to shoot, and stitching is fast, directly in planar, aka rectalinear projection. The capture was RAW, but no big tweaking...

 

[Bart_van_der_Wolf]

Did you ever shoot parallel stitches inside rooms? Could you show us some examples?

No, since I know (from handheld panos) they would produce parallax ghosts in the foreground (tables and such) I've avoided them. I'm strictly entry pupil oriented in my stitched shooting, unless it is of something that doesn't fit on the flatbed scanner. Scanned stitches are only offset and rotation corrected.

In a few weeks I'll show some examples of large natural light church interiors that I'm working on, but I'm too busy with selling the parental house, and the auctioning of the furniture right now. The shots have been taken, but I'm not pleased with the HDR colors and tonemapping yet, they need some more work.

I'm also planning on shooting some ceiling decorations, and there I might also try some stepped/tiled shots, just to see how that works out. I'll get back on it.

Bart

 

[Michael Fontana]

oh, I see you've been busy ;-)

Ray and Klaus: the chairs "moirée" is not from the sensor, ratherfrom the display's resultion, or from downsampling... I verified it at 100%....

Klaus: I realised the importance of a really precise NP in the room shot, --> PS-retouche , so I redid its measure for the garden. BTW: That shot was done to planar, directly.... as the APP-wiki suggests it for architecture-typ-shots.

Comparing to stepping or flatstitches - with a shiftlens - the pano (garden) is much better, in terms of image quality. For my actual purpose - these installations - stepping would not be possible, due tosmall little rooms, and you can't walk arround, cause of the installation. On Thomas Riehle's site the flatstitches are the "Fotografische Abwicklungen"

Klaus, how do you deal with moving objects, like tree's?

 

[Klaus Esser]

Hello Michael!

"Klaus, how do you deal with moving objects, like tree's?"

If there´s movement which can´t be handled by smartblend, you can do the renderings with photoshop-layers and erase movement in the layers. Tricky thing - but works great!
Very complicated it becomes when moving leaves are in the DRI-sequence additionally . . - Photomatix blends it partially, but sometimes leaves contours.

best and goodnight, Klaus

 

[Klaus Esser]

Bart you have said it well.

Let me add. Each joint above the tripod has either play or is not true.

There is also some looseness, ie "play" on the Manfortto extention plate and also on the Arca Swiss quick-release joint. As you turn, the equipment can sag a little one way or another, especially if something is actually loose.

Check your tripod feet are full out and on stable ground. The legs must be securely locked. Same with all joints up to the camera.

A grid on your viewfinder screen will help you recognize that your verticals or true. You can move the camera around the optical axis before taking any pictures and confirm that the verticals remain true. Use a cord for shutter release. Treat the camera as if it is fragile as you rotate.

Something is really off for you to end up with a faulty stitch since we can often do a great job by hand.

Also in the software, there should be a capability of selecting common points and/verticals that would help the software align correctly.

Asher

let me add a link about perspective correction by simply set the eye level in a shot:

http://forum.autopano.net/p10343-today-00-15-51#p10343

the rest can easily be corrected by using the vertical lines tool.

best, Klaus

 

[Michael Fontana]

....... Photomatix blends it partially, but sometimes leaves contours.

yep, I had that, too, even using the new "anti-ghosting"

After filling up the harddisc with about 40 GBs of tests, I found a sadisfying way to make a five-shot-single-row "pano"; I'm aware, this is not the "squeeze ever bit out of a pixel" as Klaus is doing it; but for the purpose of next week assignement, it's fine. The artist liked the partial QTVR, as the quality of the big, flat canvas. Downsampling it to a normal print format, for catalogues, etc (A-3/300) offer astonishing details and sharpness.
Making 360 deg-QTVR is not required in that situation, but even for the partial ones, I have my finger crossed ;-)

Still trying to get better QTVR-interpolations, as I simply used this function in Doubletake. Klaus, how do you convert some planar in partial QTVR's? Scaling down the bigs canvas first helps a bit....

As far as I could see, Cubicconverter only makes round ones...

Back to the thread's topic; some thoughts: For vertical pano's, its possible to tilt the column with the panohead for 90 deg, ergo having the cam in a landscape orientation, doing some shots respecting the nodal point, then just rotating the 360 deg-baseplate, for a 2nd row? I don't think this setup is possible when having the cam in the portait-orientation....

 

[Klaus Esser]

yep, I had that, too, even using the new "anti-ghosting"

After filling up the harddisc with about 40 GBs of tests, I found a sadisfying way to make a five-shot-single-row "pano"; I'm aware, this is not the "squeeze ever bit out of a pixel" as Klaus is doing it; but for the purpose of next week assignement, it's fine. The artist liked the partial QTVR, as the quality of the big, flat canvas. Downsampling it to a normal print format, for catalogues, etc (A-3/300) offer astonishing details and sharpness.
Making 360 deg-QTVR is not required in that situation, but even for the partial ones, I have my finger crossed ;-)

Still trying to get better QTVR-interpolations, as I simply used this function in Doubletake. Klaus, how do you convert some planar in partial QTVR's? Scaling down the bigs canvas first helps a bit....

As far as I could see, Cubicconverter only makes round ones...

Back to the thread's topic; some thoughts: For vertical pano's, its possible to tilt the column with the panohead for 90 deg, ergo having the cam in a landscape orientation, doing some shots respecting the nodal point, then just rotating the 360 deg-baseplate, for a 2nd row? I don't think this setup is possible when having the cam in the portait-orientation....

Hi Michael!

I use to have the camera ALWAYS in portrait-mode for stitches (because of the nodal-adapter).
You can use it in landscape-mode of course - but remind the overlapping: at least (!) 30%.
And you should very exactly adjust to the npp of the lens, when you work at close distances as inside a room.
Besides: the npp floates in zooms!

The shorter the distance the more extreme is the correction of perspective afterwards. Making more pics with broad overlap the stitcher/renderer has a broader variety of perspective informations to make a correction. The differences in perspective between the single shots to stitch and correct is smaller, when there´s plenty of overlapping.

best, Klaus

 

[Michael Fontana]

okay, guys, last night, I shot a round one

Light was suboptimal, and no HDR was used, as the cam failed to shot auto-brackets, with non-canon lenses....

BTW: It's not far away from my home

 

[Klaus Esser]

okay, guys, last night, I shot a round one

Light was suboptimal, and no HDR was used, as the cam failed to shot auto-brackets, with non-canon lenses....

BTW: It's not far away from my home

Hi Michael!

Beautyful atmosphere and light!

best, Klaus

 

[Michael Fontana]

Hi Michael!

Beautyful atmosphere and light!

best, Klaus

Hi Klaus,
yes, dusk (or dawn) is my prefered light for buildings. So smooth.... but hard to keep the shadows open

 

[Klaus Esser]

Hi Klaus,
yes, dusk (or dawn) is my prefered light for buildings. So smooth.... but hard to keep the shadows open

The nature of shadows often is to be deep - not open . . .

best, Klaus

 

[Michael Fontana]

agree, ;-)


It happens that I write "shadows", when I mean the 3/4-tones....