I think I'm getting what you say Castenw. So long as the base of rotation is level it doesn't matter where the camera is pointing? The camera cannot be rotated around its own access unless it's perfectly horizontal to the ground?
I don't know why but this stuff can get confusing sometimes just trying to figure it all out.
lol, Micky I couldn't afford that and unless you were willing to carry it for me I don't really want it either.
pahrens wrote:
I think I'm getting what you say Castenw. So long as the base of rotation is level it doesn't matter where the camera is pointing? The camera cannot be rotated around its own access unless it's perfectly horizontal to the ground?
No, the base of rotation doesn't have to be level. The rotation should just be perpendicular to the vertical axis of the camera/sensor (and centred on the nodal point of the lens). Only if you rotate the base of the ballhead, THEN the camera has to be perfectly aligned with the axis of the ballhead base in order to prevent getting a curved panorama, which makes its use quite limited. That is why you need a panoramic adapter on top of the tripod head (at the base of the camera).
As Carsten said: imagine the camera is pointed straight up to the zenith. If you want to pan the view of the camera to make a panorama, the rotation needs to be sideways. If you rotate the base of the tripod head though, the camera would just move in a circle about the zenith.
I've never bothered with a pano head or anything else, although I did build a bracket at one point which would swing my camera around on the nodal point. I used it for a while but soon forgot about it. I only find problems when trying to include very near objects in a pano.
The most important thing is to have the camera mounted to a perfectly level base. I've recently bought an Acratech levelling base. It's a great bit of gear which fits between your tripod and head, and with one simple adjustment your camera swivels on a perfectly level base. No more fudging around with tripod legs trying to get my camera level. Cost me about $200 AU from B&H. Worth every cent.
As Aham says, as long as you rotate around the vertical camera axis (which is the function of the RRS PCL-1), you can make a panorama. You can point the camera down or up or at an angle, just rotate around the camera's own vertical axis, and to the camera, and thus your panorama, it will create a sideways motion.
I used to use an Acratech leveling base, but since I bought my RRS panohead, I don't use it any longer. Is someone is interested, PM bullheadllhead is a bit more flexible though, combined with a PCL-1 or similar clamp, as well as the panorail.
So you're saying the axis of rotation must be directly beneath the nodal point? Which means if you were to angle the camera pointing 45º down, and then rotated the camera 180º around the nodal axis it would be then facing 45º up? I don't want to make 360º panos but I always figured that would never stitch properly? It sounds easier just to level it with the horizon and leave room for cropping afterwards.
I've ordered the RRS pano elements package to have a go with.
Thanks for all the help too trying to drum this stuff into my thick head :-)
pahrens wrote:
So you're saying the axis of rotation must be directly beneath the nodal point? Which means if you were to angle the camera pointing 45º down, and then rotated the camera 180º around the nodal axis it would be then facing 45º up?
Yes, that's right. But although this seems slanted to you, to the camera it is straight sideways. Imagine sitting on the camera as you turn it. The stitched panorama would be linear, not banana-shaped
What confuses me then is what Peter Lik is using, http://www.peterlikexposed.com/archives/1413. He uses a Gimbal style head but no nodal rail. I've also seen a photograph of him with the RRS Ultimate-Pro Omni-Pivot package taking a photograph with the camera angled downwards.
Well, he is rotating around the central axis of the camera both sideways and up/down, so it may be that the offset between the entrance pupil of the lens he uses and the centre of the camera is negligible, just for that combination. It makes things simpler I guess, although it also means he may not be able to put a close foreground element in his shots. Are you familiar with his photography?
I've seen a lot of his photographs but I'd say that the most were taken on his Linhof 617. I wouldn't know which ones were taken with the digital setup. He uses a Phase One camera and back but the lens I'm unsure of. Is it possible to shoot with the nodal slide with a setup like that? It looks like a good setup for manoeuvring the camera in whatever direction while keeping it level.
If you keep the camera level (left-right and forwards-backwards) there is only rotation around the vertical axis left. This can also be accomplished with a normal ballhead. The point of the setup he is using is that tilting forwards and backwards leaves the centre of the camera in the same place, whereas on a ballhead the whole camera would move forwards and backwards, when tilted.
The entrance pupil (not nodal point) location is not always inside the lens, so it is possible that with his lens, the entrance pupil is actually inside the camera. I doubt it though. His lens is very short, and I would guess that it is the 45, 80 or something similar. I think he is just cutting his kit and either putting up with a small compromise in quality, or a restriction on how close he can have something in his panorama.
When you want to do multi-row panos or even vertical panos, you have to tilt the camera at any rate. Only doing horizontal single row panos would be very limiting/boring...
pahrens: Are you using Photoshop CS3 or newer to do your stitching? If so, then you might want to know about Edit>Auto Align Layers, followed by Edit>Auto Blend layers.
The first time I tried this tool, I just sat there with my jaw on the floor. I USED to spend hours doing this work. Now it takes seconds. It doesn't matter if the waves are different from shot to shot, or if you didn't adjust for your camera's nodal point, these two tools figure it out and blend it pretty flawlessly. It even gives you nice clean layer masks for each layer.
Like the OP, that is what I want too - boring MP rich simple one row panos. So I throw my lot in with wbrad, and report that the Acratech levelling base indeed looks the business for serious trekkers, at 240 grams, it now sells at B&H for $150 Aust dollars. It also is compatible with typical small ballheads like my Markins Emile Q3.
It took a few minutes to get the need for it - I use the ballhead for all adjustments at present - but now I get it. For those interested in a full er discussion, see: http://photo.net/nature-photography-forum/00OE1U?start=0
in which Ellis V learns a bit about it too.
DD, you are in the 'isn't stitching software wonderful' camp, and I do hope you and others who share your views are right - I believe you are, except for special needs and purists. Thanks all.
Yes, you can use a leveling head and a normal ballhead instead of a PCL-1-type clamp, to get level rotation at the base of the ballhead. It is bulkier but cheaper, probably.
