QE-2 at West Circular Quay, sydney

Thank you, Tony, so display on camera in "true color" can be seen as advantage. MEM, did we ever have enough mem on our machines? I went to a 2 gig now (in total 3 gig), as I dont want to take the lap arround during weekend trips. BTW: Doing this stich-pans, which head do you use. I still use a simple one (168) and always have to fight with PanaVue. I know - NodalPoint - etc - does a proper head really make life simpler?

Regards Axel.

You have to use a proper panoramic head. I use a Manfrotto "Big Heavy Head" - can't remember the model number.

 

It has X,Y sliders to position the camera/lens combination. For each camera/lens combination you have to find the "nodal point" of the lens and position it above the axis of rotation of the head. The nodal point is that point where parallax error through the lens (i.e. as observed in the viewfinder) is minimized, no matter how much you rotate the camera on the head. You judge parallax error by eye, observing the spatial relationship between a "near" and a "far" object. The aim is for the two objects to have the same spatial relationship (no parallax error) no matter how far to the left or right the camera is rotated. When you achieve the nodal state position, you can take multiple frames in the sure knowledge that for each frame any two objects will maintain the same visual relationship to each other as you rotate the camera. This makes stitching straightforward.

 

If you do not find the nodal point then your two reference objects will have more or less air gap between them as you rotate and the stitching software will be presented with a situation where the two objects appear to have moved... not a good thing for stitching.

 

The nodal point is set up BEFORE you go out to shoot, under controlled conditions.

 

To set my nodal point I first visually set the left/right positioning of the camera lens to be in line with the axis of rotation of the head. This is easy: you just align the centre of the lens with the centre of the head.

 

Next, I position the camera so that, when viewed through the center of the viewfinder, a "near" vertical object and a "far" vertical object have a tiny air gap - a backlit slit really - between them. I then rotate the head and camera to the left and right and observe the air gap (remember: it's best to have this backlit so you can see it clearly). If the gap grows or diminishes as you rotate from left to right (it's a tiny gap, so any change is easy to observe) then the lens is not positioned nodally. So I shift the camera forwards or backwards (with the slider) and try again until the air/light gap is the same at left, middle and right, that is, there is no parallax error whichever way I rotate the camera. I then mark this point on my sliders for future reference.

 

Remember: there is a different nodal point for every camera body and lens combination. So mark these points on the sliders when you find them.

 

With Panavue you have to have a reasonably large overlap between frames. I use 24 degrees between frames. This leaves an overlap of about 25%. Panavue will start to hesitate if the overlap is much smaller than this.

 

Digital cameras are good for stitched panoramics as there are no registration errors due to scanner film carrier irregularities between frames. If you get your nodal point correct then you should achieve a high quality stitch. But there are a couple of precautions to take.

 

First, ALWAYS do a Lens Wizard for each panoramic you take. Every panoramic is slightly different in tilt to the last one. Tilt differences can screw up a Panavue panoramic, unless you account for them with a Lens Wizard project.

 

For ther uninitiated, a Lens Wizard is a method in Panavue where you take two or three frames and manually declare several sets of points in adjoining frames to be equivalents. For example, if a flagpole is in the overlap area between two frames then the tip of that flagpole might be an "equivalent" point and could be marked as such. You mark the tip of the flagpole in each frame with a visual "flag" provided by Panavue. From then on Panavue will regard these flag points as the same point in the panoramic image you are photographing, and will try to overlap them in the final stitched image. Any set of equivalent points will do as long as they're evenly spaced throughout the overlap area.

 

Once the sets of equivalencies are declared by the user, Panavue then tries to overlap these points into a stitched image. To do this it applies a spherical warp ("projects" the frame onto the inside of an imaginary sphere) to each frame and then sees if each of the equivalent points can be made to exactly overlap at the warp factor. Panavue iterates this process until they all fit and the stich is seamless. The user then saves these "lens" parameters. The next step is to perform the actual stitch.

 

For this you need all your frames, not just the three samples you used to figure out the warp required. If your "lens" has been calculated accurately then the images should stitch together easily. For this shot I took 15 images and used about 12 of them (it's not quite 360 degrees). Most of the work I did in stitching these 15 images was done in the Lens wizard part of the software, with just three adjacent images that were detail rich acting as references for the whole 15. Once the "lens" was calculated it could be applied to ALL the images.

 

But sometimes - as in this image - there are large areas of blank sky and rippling water, or other either bland or moving artefacts. Panavue on "automatic" stitch can't find equivalent points in blank sky or rippling wavelets and so it will guess, usually wrongly.

 

The program, however, does have a "Flag" stitch. You can position visual flags over points of equivalence, just like in the Lens Wizard. This will force Panavue to put these points together, and only then apply the warp to the individual images to make them fit. The flags represent anchor points.

 

If there is insufficient detail even for manual placement of flags, then with digital (i.e. accurate registered) images you can just use the preset flag positions provided by Panavue. They will all be at the same pixel locations in each frame to start with. Leave them alone and you have automatic perfect placement of your flags as these are digital images without any registration errors. You should then get a perfect stitch, even if your scene has distracting artefacts like moving water and bland clouds or sky.

 

So, in summary, if you use Panavue with a digital camera:

 

1. Get your nodal point correct before you shoot.

 

2. Perform a Lens Wizard for each panoramic image.

 

3. Use "Stitch with 2 flags", but don't set the flags yourself. Just use the default positions.

 

Sorry for the software-specific post, but Axel did mention he was having trouble with Panavue.

 

A couple of other points, now that I think of them, for general use:

 

1. Remember you're photographing a wide scene, so get your exposure right with that portion of the scene which has the greatest variation in light conditions.

 

2. Then use your camera on MANUAL exposure, not automatic.

Peter Daalder: What's happened to Bernhard? Did we give him a scare?

 

---

 

Tony Dummett: shhhh!... ... He's having a word with his wife. "

 

I'm busy reading the literature provided by Peter, checking out jobs, writing CVs, applications and stuff. Sorry for not participating in your nice conversation, I'm enjoying the pic but my families future is what's on my mind now.

Bernhard, here's a potentially interesting link for you. However, beware (as mentioned earlier), you will have a much wider choice of jobs in your area of expertise on mainland Australia and you'll definitely be able to get a higher salary. On the other side of the coin, is the cost of living - housing in particular. For instance, if you were looking to buying a property in Tasmania, you'll be able to find something down here for half the price you would pay in many mainland locations. The compact nature of Tasmania also adds a nice bonus, travelling time to work...

If you found something in Hobart, you could reasonably expect to travel to your workplace in no more than 30 minutes. Up here in Launceston, it takes me only 5!

What's all this about two headed sheep?

 

Great shot Tony. The panorama format really does the Quay justice.

 

Sorry to hear you're stuck in Launnie.

 

bernhard.

 

have you considered canada? i have a pair of german friends (a couple) who think it's wonderful here, even though--as a big wagner fan--i can never hope to understand why. my stereotypes tell me it's similar to down-under over here, though a bit more conservative and boring. one clear advantage is that you can avoid the questionable mating practices pointed out in this thread merely by staying away from the province of alberta--where, as the saying goes, "men are men and sheep are scared."

Hi Vuk,

 

Good photographs seem to attract good people.

 

Yeah, I thought about Canada and we will look in this direction as well. As to the Wagner thing, you known, Wagner is very German but he is also history. When talking about about a place to live, I'm more concerned with the future.

 

Why don't you book a one-way flight back to 'Old Europe'? In the end it's human beings that count and not buildings, books or vinyl records.

Thank you Tony, I did not really use the Lens Wizard up to now, but after your suggestion I went that way and - YES this is really working fine! This makes life much simpler. Regards Axel

Glad to be of help Axel.

nice balance... very nice

Very nice photo. r.Jitka

Wonderful picture . Congratulations !

 

Regards Dan