NN3 leveling problem

[katprat]

I have had my NN3 for about a year now, and have noticed a worsening problem with leveling. I mount my camera/lens combo (Nikon D200/Sigma 12-24mm) and level as I always have, but now, the resulting image is crooked. I'm attaching a sample image, photographed with the level on both the tripod legs and the NN3 built-in level spot on. What could be causing this and how can it be fixed? It has gotten worse over time and now Panorama Factory is starting to have stitching issues that it's not had before. Any help is greatly appreciated!

[nick fan]

Not sure of Panoramic Factory, other stitchers such as PTGUI, Aotopano pro have leveling feature. It can be done in 30s.


nick

[gagartist]

I have the same problem. My solution which is far from perfect: I level the NN3 before attaching the camera rather than attempting to level the head with the weight of the camera. Then as I snap each picture I will watch the bubble to make sure that things are still level. If not, I will actually hold the camera so that the bubble is centered. This has improved things a lot and has saved me from buying the NN5 which is what I should have done in the first place. The weight of my Canon 30D plus Tokina 12-24 and flash is too much for the NN3. Hope this helps!

[nick fan]

I have the same problem. My solution which is far from perfect: I level the NN3 before attaching the camera rather than attempting to level the head with the weight of the camera. Then as I snap each picture I will watch the bubble to make sure that things are still level. If not, I will actually hold the camera so that the bubble is centered. This has improved things a lot and has saved me from buying the NN5 which is what I should have done in the first place. The weight of my Canon 30D plus Tokina 12-24 and flash is too much for the NN3. Hope this helps!

I hope your flash is not on the hot shoe mount, otherwise, you are overloading NN3 or even NN5. The size of flash on the hot shoes generates a large torque on the vertical and upper rails. Many Pros don't recommend using flash for panos. If you must use it, use it off camera.



Nick

[tomtomtoo]

Then as I snap each picture I will watch the bubble to make sure that things are still level. If not, I will actually hold the camera so that the bubble is centered. This has improved things a lot and has saved me from buying the NN5 which is what I should have done in the first place. The weight of my Canon 30D plus Tokina 12-24 and flash is too much for the NN3. Hope this helps!

I have noticed a similar levelling issue.
Using NN3 II with EZ-Leveler-II, Canon 100D + Sigma 8mm F3.5. I mount camera then I level. When I rotate to the next click stop the bubble on the Easy Leveller is off centre. In some cases it is halfway out of the centre circle! When moving to the next click stop the bubble has shifted position again.

I am new to Nodal Ninja and like the set up, but am finding more trouble in the alignment of images the stitching process than i was before when using the 303sph, Canon G5.....a 32 shot panoramic process.

I realise the stitching process isn't perfect, but is this lack of levelling with the NN3 II a factor in the misalignment of the images?

ps. I'm using the 400D rail settings ie 51 lower and 87 upper as 1000D is the updated model to the 400D.

[Terrywoodenpic]

I too use a nn3 mk2. Previously I used the mk1 and prior to that the NN2.
The MK1 and NN2 can become loose or be inadequately tightened, But this is rare on the MK2.

Levelling of the panorama is far more to do with the selection of control points and the software used than than it is to do with the hard ware.
Panorama software does not know anything about what is in reality up and down, it just maps on to a sphere or part of a sphere. and then remaps to the projection you have chosen.

PTGui and PTAssembler have simple and almost instantaneous means of correcting for vertical and horizontal.

A pano bracket would have to be much like a variable jelly to create problems, these problems would be more to do with shake than alignment between shots.

The NN Bracket will always rotate exactly in the plane of the rotator, the bubble is only for setting up the first shot.

Even if the bracket is overloaded with a flash... to the extent it is no longer at right angles to the plane of the rotator, this will have little effect on stitching.
What effect it does have, will be because the "nodal point" has moved off centre in the direction of the lean. Even this loss of parallax will only have an effect on close subjects.

[nick fan]

I have noticed a similar levelling issue.
Using NN3 II with EZ-Leveler-II, Canon 100D + Sigma 8mm F3.5. I mount camera then I level. When I rotate to the next click stop the bubble on the Easy Leveller is off centre. In some cases it is halfway out of the centre circle! When moving to the next click stop the bubble has shifted position again.

I am new to Nodal Ninja and like the set up, but am finding more trouble in the alignment of images the stitching process than i was before when using the 303sph, Canon G5.....a 32 shot panoramic process.

I realise the stitching process isn't perfect, but is this lack of levelling with the NN3 II a factor in the misalignment of the images?

ps. I'm using the 400D rail settings ie 51 lower and 87 upper as 1000D is the updated model to the 400D.

First of all, make sure no wobbling between EZ-LII and tripod, no wobbling between EZ-LII and NN3II, no wobbling between lower rail and the rotator. If there is wobbling, fasten EZ-LII on tripod, fasten the rotator on EZ-LII or faster the rotator tension knob.
To read the bubble level accurately, read directly ABOVE the bubble. If you don't get the initial level right, bubble will move out of the black circle. The bubble is very sensitive, if it does not move out of the circle. You get acceptable level.
As Terry pointed out, leveling does not cause stitching error. It just affects the appearance of horizontal (wavy) and vertical (tilted) lines.
http://www.panoguide.com/howto/panoramas/level.jsp
Ptgui has auto straighten panorama function in the panorama editor. So it just takes a few seconds to correct the level.
Fisheye lens has floating NPP which varies with angle of view. It can cause more problems at the seam than a rectilinear lens. The settings in the database is a starting point, you need to confirm the settings yourself. Follow this excellent tutorial
http://www.johnhpanos.com/epcalib.htm
If you get the right NPP settings and still see stitching errors, you can upload your source photos. many experienced people will try to diagnose the problem for you.


NIck

[waters]

I suspect that the problem lies with the NN3 rotator base, which by design must have some play to allow rotation. The spring loaded detent plunger needs this play to function, and I believe that as the rotator gets older the slop increases. The new rotators with the side plunger design eliminate this type of play, as the rotation is on a bearing ( I think ). Maybe a new detent plunger might help? I think they are supplied. I found that there was always a compromise between ease of rotation andplay with the NN3 rotator, but OTOH, the compactness mostly outweighs the problem. The compactness was what originally drew me to the NN, and like many cars, subsequent models with more bells and whistles tend to get larger. In the case of the RD rotators, the extra weight and size are well worth it, as they are a huge improvement. I know that when I get set up to shoot I don't have to worry about the tension adjustment every time.

[DemonDuck]

I suspect that the problem lies with the NN3 rotator base, which by design must have some play to allow rotation. The spring loaded detent plunger needs this play to function, and I believe that as the rotator gets older the slop increases.

There is a little hex screw in the bottom of the rotator to increase the spring pressure on the detent plunger. You have to be delicate with the adjustment. There has to be just enough spring pressure to seat the plunger firmly into the detent dents yet not so much as to lock the rotator in place because the pluger can't be pushed down during rotation. There should be a little hex wrench in your parts kit.

[Terrywoodenpic]

I suspect that the problem lies with the NN3 rotator base, which by design must have some play to allow rotation. The spring loaded detent plunger needs this play to function, and I believe that as the rotator gets older the slop increases. The new rotators with the side plunger design eliminate this type of play, as the rotation is on a bearing ( I think ). Maybe a new detent plunger might help? I think they are supplied. I found that there was always a compromise between ease of rotation andplay with the NN3 rotator, but OTOH, the compactness mostly outweighs the problem. The compactness was what originally drew me to the NN, and like many cars, subsequent models with more bells and whistles tend to get larger. In the case of the RD rotators, the extra weight and size are well worth it, as they are a huge improvement. I know that when I get set up to shoot I don't have to worry about the tension adjustment every time.

Play is certainly not the problem.
Although any sag in the rotator slightly changes the angle at which the head rotates ...
it is a constant, as it is a function of the weight of the camera and lens, and the bending force on the arm and rotator.

In some cases these forces might be sufficient to change the attitude of the tripod column or additional heads, but it would not be great enough to change the relative sag between the parts of any rotator as they are turned.

The stitching program can not only deal with this automatically, but also perfectly stitch shots, deliberately and randomly pointed up and down.

The requirements of a pano head solves different problems.
Firstly they allow the positioning of the “nodal point”
They provide a convenient means of rotating the camera in both vertical and horizontal planes. ( neither of which need any real precision)
A good pano head should also hold the camera steady during exposure.

The more important factor is the choice of suitable key points between the images.
Auto selection often chooses quite unsuitable points such as…
Clumping them in a small area or placing them on moving objects (people, trees leaves clouds, water etc.) a better result is always obtained by manually placing them in the area of the seam with a wide a spread as possible.

As I mentioned earlier, the exact position of the shots is of no concern to the programme. The stitcher only involves itself in positioning the shots relative to each other. All other considerations are that of the user and under their own control.

[waters]

Two NN3 users reported a similar problem. Failing a catastrophic bending of the upper arm, or the camera not being held on the upper arm squarely, I'm not sure how play is " certainly not the problem ". The play needed to allow rotation is observable with other types of pano heads using the same design, i.e. a Kaidan that I owned. No doubt any decent stitching program will be able to handle an out of level set of shots. I can also report from my experience with my NN3 & NN3 MK II that keeping the tension set properly was difficult; too much tension and difficult rotation, too little tension and too much play. I would entertain other ideas of how the shots were so out of level after the users had not had this problem before!

[DemonDuck]

Two NN3 users reported a similar problem. Failing a catastrophic bending of the upper arm, or the camera not being held on the upper arm squarely, I'm not sure how play is " certainly not the problem ".

When I first got my NN3, I noticed that the detent ring lay flush one way and rotating it 180 degrees caused it to be slightly raised on one side. That caused a little wobble. Now when I put a detent ring in, I check to see that it is flush all around. I reported this some months ago.

[Terrywoodenpic]

Two NN3 users reported a similar problem. Failing a catastrophic bending of the upper arm, or the camera not being held on the upper arm squarely, I'm not sure how play is " certainly not the problem ". The play needed to allow rotation is observable with other types of pano heads using the same design, i.e. a Kaidan that I owned. No doubt any decent stitching program will be able to handle an out of level set of shots. I can also report from my experience with my NN3 & NN3 MK II that keeping the tension set properly was difficult; too much tension and difficult rotation, too little tension and too much play. I would entertain other ideas of how the shots were so out of level after the users had not had this problem before!

I do not doubt that you have experienced sag...or that you had difficulty correctly tightening the rotator on a NN3, Though this has never been my personal experience with any rotator of any make, which is one reason why I have not felt the need to move on to the new advanced heads, the main one being that as I only use one camera and focal length for pans, so that I do not need the excellent additional features.

What I maintain is that limited sag such as you describe can not cause stitching problems.

[Terrywoodenpic]

I took this small pan today. poking my camera through a slit in a window... as such it was hand held , two shots. This was way out of horizontal far more than any bracket with slop
However it stitched quite well auto every thing though somewhat on the slant.
I repositioned the keypoints to more suitable ones and re-optimised .

The first shot shows the Preview screenshot after I had added vertical correction lines.

The second shot is the final image after stitching and blending and adjusting curves in photoshop.

I used PTAssembler and smart blend.

[psj]

Katprat,

How does your NN3 attached to the tripod and do you raise the centre column?

Maybe the wobbling bits are the tripod and not NN3

I did indoor shoots with 30D + Sigma 8mm with 550EXII flash mounted on NN3 lower rail (with a ball head) and had no wobbling issues.

And that was on a NN3 Mark One