Please, does anyone already have the Lower and Upper Rail settings for this setup : Canon 7D with Battery Grip + Nodal Ninja 5 + Sigma 8mm.
I'm arriving in NY next week. I'm going to stay for just a few days and didn't want to spend time searching for the NPP.
I just want to make sure my settings will be correct cause I'm starting in 360VR Photography.
using a battery grip might influence only the lower rail setting if there is now offset of the tripod mounting screw position from top to bottom within the battery grip. The MD-200 battery grip from nikon for D200 has an offset of these positions which changes the upper rail setting with a difference of 6mm. Besides this it changes the lower rail setting as well.
The NPP of the Sigma 8mm changes its place in the lens from the golden ring to the front of the lens using different focus positions. So if you like to compare your settings, both of you might use the hyperfocal distance for the test and while shooting your panos.
For myself i decided not to use a battery grip, cause it is not very stable and the camera lens combination moved away from the vertical line some degrees. This makes extra work to set the photos back to the vertical in photoshop for example. But try
and experience yourself.
The NPP of the Sigma 8mm changes its place in the lens from the golden ring to the front of the lens using different focus positions.
Heinz, That is not true. The variation in entrance pupil position over focus settings ranging from infinity to 0.135m is only 1.5mm approx. Between the infinity setting and 0.5m, the variation is negligible. Further, the golden ring changes position with the entrance pupil, and relative to the ring, the entrance pupil hardly moves at all. The apparent position of the entrance pupil varies significantly when viewed at different angles to the lens axis, which is why the NPP setting varies according to the number of shots around that you take. That determines the angular position of the seam across the image frame, which is where it's most important to eliminate parallax. Parallax effects cannot be eliminated entirely when using a fisheye lens.
I don't understand why so much time is spent setting up a panohead. I just timed myself setting up my 40D+Sigma 8mm on a NN5, completely from scratch (including finding and setting up the tripod etc. and then determining the NPP). The entire process took 10 minutes exactly. No photos were taken, no laser pointer used, and I didn't even look through the veiwfinder or at the liveview screen. I shot a test panorama in my kitchen and that stitched perfectly in PTGui.
ok, I might should have said "it slides along the principal ray". But to make it clear, I added the link. In the beginning, I like people to try to be precise, knowing that 1.5mm may be negligible and the software might cover this.
But actually the "theme" of the questions asked were about differences in rail settings they found, with and without a battery grip and the influence of it.
By the way. Do you really want to say it took you only 10 minutes for the FIRST TIME you checked the NPP of this camera lens combination? I do not believe that. They are beginners, and might be you forgot the hours you had to spend to be experienced like now.
As I remember there are not so many Einsteins, Beethovens and Bachs in the world till now and even they had to take their time to learn till being a genius.
Heinz, When I set up my panohead in 10 minutes, it was of course not the first time I had done this, but the particular fisheye lens and camera makes no difference. The procedure is basically simple and straightforward and requires virtually no technical expertise whatever. When you have done it once, you can certainly do it in little more than 10 minutes. The only action needed is to view the entrance pupil and centralize it by (1) sliding the vertical rail sideways (horizontal position), (2) rotating the camera on its mounting screw to the upper rail (vertical position). The centralized position must be maintained when the upper and lower rails are both rotated through 180 degrees. Then (3) adjust the position on the upper rail to centralize the entrance pupil when the panohead has been rotated from the straight ahead position through half of the normal yaw increment used when taking a panorama. No special skill is needed to judge if the entrance pupil is centrally positioned in an improvised sight, nor what action is needed to take if it isn't. For a sight, I used an empty ballpoint pen barrel taped to a pan & tilt head on a cheap spare tripod, which takes no time at all to set up. But you can maybe do something like this with a broom handle taped or tied to a chairback, with the pen barrel secured to a thin card slide by an elastic band:
But you can easily devise something from things found in any household, like a needle in a strip of cardboard illustrated in my tutorial, where full details are to be found: http://www.johnhpanos.com/epcalib.htm.
Just to correct. I was wrong about the lower rail settings.
I got the 112mm setting taking a nadir shot and finding exactly the center of the picture measuring it in photoshop:
But measuring phisically whit a ruler, the camera at 0 degrees, the center of the lens in the lower rail it's on 116mm.
I've used Smooth method to adjust the lower rail setting and find the OSP (optimal stitching position).
When I stitch in PTGUI whithout optimizer I got this (looks ok to me):
Unfortunately when I stitch in PTGUI using optimizer (heavy + lens shift) I got this:
Showing that the vertical arm on the lower rail needs to be moved to the left a little.
When using Smooth method (OSP) to find the NPP, I need to use or not the lens shift optimizer ?
Add 13 mm for the NN5 and test for lower rail setting. Upper rail setting Nikon D3 Sigma 8mm/f3.5 is 75mm. Just in front of the golden ring.
For the test of the settings I only use heavy in the optimizer. When I stitch with zenith, I use heavy + lens shift.
With the Nikon combi you will see a bit of the NN5 in 90° position, but this does not show in the stitched images.
I tested 3 shots around, and I am not pleased. You have to use a wide feeld of view. With the Sigma, I go for 4 shots. At least on the R1, as a leightweight and quick solution. With the NN5, I prefer the Nikkor 16mm/f2.8 fisheye with 6 shots around.
Toni, You should always include the lens shift parameters when optimizing a fisheye lens. It's important to have control points only assigned on the floor and surroundings - not on the panohead or tripod. That demands some manual input to the running of PTGui. That way, you should see the floorboards nicely aligned and any misalignment of the pano head due to parallax will then be revealed. The problem with using Smooth's method of finding the OSP is that you need to be reasonably proficient in using PTGui (or similar stitching software). The newbie to panorama making generally does not have this experience and it cannot be acquired overnight. The methods described in my tutorial require no stitching experience nor any special equipment or tools like laser pointers. However, they do enable the pano head to be set up perfectly adequately very quickly, and the newbie can progress onto shooting panos and stitching without delay.
I moved my lower rail just 1mm to the left. So my final setting for Lower Rail is : 115mm.
Analysing nadir footprint just after optimised stitch (fov, a,b,c,d,e), I got this:
Is really necessary to adjust my upper rail everytime I make a pano because of the changing position of the NPP on fisheye lenses ?
Probably the answer is yes, but I'm asking it because when I stitch in PTGUI with different positions in the upper rail, but near the NPP, it stitch apparently correct with no parralax errors.