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markmc90
03-10-2013, 09:46 PM
I've been using the R1 for a couple days now on my D800 and shaved 10.5. I'm really happy with the results for the most part. I'm getting great spherical panoramas with no stitching issues, but I need to get rid of the tripod in the shot. What's the best way to do this with my setup? I'm currently using PTGUI.
Thanks!

John Houghton
03-11-2013, 02:59 AM
When the ground beneath the tripod is relatively plain, you can often simply clone out the tripod using Photoshop. It's best to extract a rectilinear view of the nadir area from the stitched equirectangular panorama to facilitate this. The easiest way is to generate 6 cube faces using a program such as Pano2VR or Pano2QTVR, edit the nadir face, and reassemble the cube faces back into an equirectangular image. Or you can use the Photoshop plugin by Rune Spaans: http://www.superrune.com/technical/software_spheretocubic.php .
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To replicate the true surface at the nadir, you need to take a shot of the nadir area with the tripod shifted out of the way and the camera at or close to its original position. This can be done in a variety of ways. Outdoors, you can simply hand hold the camera pointing down with outstretched arms (on or off the tripod). Indoors where the poor light levels dictate relatively long exposures, you need to use the tripod. If you release the tilt knob of the R1, you can tilt the camera down to its maximum extent. Then lean the tripod forwards with your foot on the bottom of the (lengthened) rear leg to prevent it toppling over, as illustrated in this article: http://www.rosaurophotography.com/html/technical6.html . An easier solution is to use the Nodal Ninja nadir/zenith adapter: http://shop.nodalninja.com/ultimate-r1-r10-zenith-nadir-adapter-f6112/ .

The nadir image should be stitched into the panorama using viewpoint correction (PTGUI Pro only). This corrects perspective differences in the nadir shot that arise from not positioning the camera precisely with the original no-parallax point. While viewpoint correction will work accurately even for quite large displacements of the camera, it's best to get the camera reasonably close to the original position whenever possible. See these tutorials:
http://www.ptgui.com/examples/vptutorial.html
http://www.johnhpanos.com/ptgvpt.htm
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John

markmc90
03-16-2013, 04:33 PM
Thanks for your reply. I'm still having issues with this though. My panoramics are coming out great, except for the ugly tripod in it! Do you think it could be a problem of the floor not having distinguishable control points. Some of the shots I've had problems with were laminate floors that are very plain. Do you think the Nadir adapter would help?

John Houghton
03-16-2013, 05:19 PM
It's not quite clear what the problem is that you are having. The nadir adapter might help, but you still need control points to align the nadir image - assigned manually, if necessary. If the floor appears lacking suitable features for control points, you can sometimes find small spots (dust, scratches etc.) that are visible when zoomed right in. Otherwise, you can scatter some temporary features around the nadir - e.g. five or six small coins or adhesive spots. These can be cloned away from the final stitched panorama image. If you cannot get the nadir properly stitched, upload a set of (jpeg) images somewhere, and I and no doubt others will take a look. You can use a free file sharing site such as http://www.ge.tt/ if you don't have your own private web space.
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John

markmc90
03-17-2013, 08:54 AM
Thanks John. I'm not sure if the problem is me being unfamiliar with PTGUI Pro, or if I did something wrong when taking the pictures. Here's a link to one of the panoramics I did that I'm having stitching issues with. Again, thank you for your help.

https://www.dropbox.com/sh/f1u0spn8b63mzzy/fk_rXlWnCt

John Houghton
03-17-2013, 09:42 AM
Mark, The images stitched ok. I've uploaded the project file and stitched image to http://www.johnhpanos.com/Pano5.zip
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John

hindenhaag
03-17-2013, 09:45 AM
Hi Mark,

The pics on dropbox are very small and I can not open them in the PTGui. I did not use dropbox before so I do not know if this is my fault.

The use of the R1/R10 Nadir Adapter is very complicated. http://ge.tt/4uLm9Mb

So what you have to do is to reset the old NPP to the whole system before shooting the Nadir shot. So you have to raise your center column and shift it sideways to take your nadir shot.

Would be easier to take a handheld shot or move aside with the tripod, use R1 built in Nadir Shot Position. So place a coin below your tripod, move the R1 forward till it touches the the flat surface. Now move the tripod backwards till you can focus to the coin and shoot your Nadir Image. For this method you have to use the Full Viewpoint Correction described in PTGui.

In case you are not using a pole might be a good idea to have a look to the Compartment "Custom Heads" to see the R1-S. Of course it is a little bit bigger, smaller than NN3, but has the opportunity to shoot Zenith and Nadir1 and Nadir2 Shots in NPP with Nadir Adapter.

Heinz

markmc90
03-17-2013, 09:47 AM
That's good to know. It must be something I'm doing in PTGUI. Are you following the same process as outlined in the above tutorial?

markmc90
03-17-2013, 10:00 AM
John,
Can you give me a brief outline of your steps to stitch this?
Thanks.

John Houghton
03-17-2013, 12:08 PM
Mark, I am following the steps detailed in my tutorials, viz: align the horizontal row of images first, making good any deficiencies in the control points assignments to get a good spread. Be sure to include the lens shift parameters in the optimization. Then roughly align the nadir using a few manually placed control points, and then check the viewpoint option on the nadir before repeating the optimization. The optimizer report should then be as good as it was before the nadir was added. Mask away those parts of the nadir image that are not part of the flat floor.
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John

markmc90
03-20-2013, 02:14 PM
Thanks again for your help John. I'm tying a new one today and having problems again. When I follow your steps everything looked great except a little piece of tripod was showing in from one my non-nadir shots. I masked that away but everything went haywire after that. The images were all rotated and optimizer said it was a bad fit.
I'm sorry to keep bugging you with this but I feel like I'm missing something. The nadir adapter is on it's way from Nodal ninja so hopefully that helps.

hindenhaag
03-21-2013, 12:32 AM
Hi Mark,

Might be something with your calibration. The first pic is made of 4 shots just by deleting bad control points. You see a little misalignment and might be you should move a little bit to the right. The second pic is made with John's stitch by deleting the masks and stitching to see the output.

May be that's the point.

824823

Heinz

John Houghton
03-21-2013, 01:14 AM
When I follow your steps everything looked great except a little piece of tripod was showing in from one my non-nadir shots. I masked that away but everything went haywire after that.
When "everything looked great", I assume you had aligned the images with the optimizer but there was a bit of tripod visible in the output image. If you then just mask the relevant image to remove the tripod bit, this will not affect the alignment of the images in any way. If the viewpoint nadir has at this stage been included and aligned, all you need do is generate the output. If you are at the stage where you need to add the nadir and align it to the already aligned images, you can uncheck the y,p,r boxes of all the images except the nadir before running the optimizer. The images cannot then go haywire as they are locked in position. If at any stage things do go haywire, just run Undo (ctrl+Z) to restore the project to the previous sane state and try to identify what it was that you did to make things go awry before having another go with the optimizer. (Never run the Align Images function twice, BTW).

John

markmc90
09-03-2013, 05:43 PM
I'm back! After a few months of not shooting 360's I'm back at it and having issues again. I really appreciate your help! I can stitch my 4 images into a nice 360, but when I include the nadir shot the optimizer says it's a very bad match. Any suggestions? Thank you!

John Houghton
09-03-2013, 11:49 PM
All the suggestions one would like to make are already in the earlier posts of this thread. For the nadir shot, you should only have control points on the flat surface of the floor/ground. Without viewpoint correction selected, you will expect to get a "bad" optimization. Accept this result and then select VP for the nadir image only. A further optimization should now give a good result. If this doesn't work, upload jpeg copies of the images and your saved project file to your personal web space or a free file sharing site such as www.ge.tt , and post a link to them here.

John

nick fan
09-04-2013, 08:13 AM
All the suggestions one would like to make are already in the earlier posts of this thread. For the nadir shot, you should only have control points on the flat surface of the floor/ground. Without viewpoint correction selected, you will expect to get a "bad" optimization. Accept this result and then select VP for the nadir image only. A further optimization should now give a good result. If this doesn't work, upload jpeg copies of the images and your saved project file to your personal web space or a free file sharing site such as www.ge.tt , and post a link to them here.

John

Besides, you can mask the nadir shot to exclude area that is going to give bad control points.

Nick

RockvilleBob
11-23-2013, 05:40 AM
Hi John
Does your tutorial http://www.johnhpanos.com/ptgvpt.htm include the use of the Nodal Ninja Nadir Adapter? I just ordered the adapter and plan to run some tests in the next few days. After taking the two Nadir shots - Nadir1 and then Nadir 2 (after moving Double Pivot Point Distance) do I load both images into PTGUI Pro and mask out the tripod and then stitch?
I guess I am looking for a step by step work flow. I will be using six images using the Bower 8mm mounted on a Pentax K-3, NN6 RB16. Then I take one vertical Zenith shot and two Nadir shots, the second taken after switching the NN Nadir Adapter and moving the tripod DPD.
What I would appreciate is the steps in PTGUI for loading the 9 images. I was thinking of loading them in and masking the tripod that would appear in the two Nadir images - is that all I need to do?

In production I will be using HDR taking 5 shot sequences in a cathedral using 2 EV steps. In the past I have just loaded all the images into PTGUI and let PTGUI do the stitching and HDR. The I take the HDR file and render it using NIK HDR Efex Pro. My question is: Should I take the 5 stitched panos generated by PTGUI as an option and then have NIK HDR EFEX PRO do the merge as well as the rendering.
Thanks for all you help John.

John Houghton
11-23-2013, 06:40 AM
Hi John
Does your tutorial http://www.johnhpanos.com/ptgvpt.htm include the use of the Nodal Ninja Nadir Adapter?
The tutorial doesn't specifically refer to the nadir adapter. All the images that are shot with the camera in the NPP position can be stitched together. Any images shot from an offset position can be then be added and optimized separately into position. Any images shot from a position only very slightly offset should stitch ok with the others but maybe switch on the viewpoint correction for that image to fine tune the optimization at the end. If you are optimizing with full manual control via the optimizer's advanced tab, all the images can be added at the outset but selectively included in the optimization by using the check boxes in the "Use control points of.." list.

John

hindenhaag
11-23-2013, 07:26 AM
Hi Bob,

here you find what you are looking for: http://vimeo.com/65994333

It's a video on how to use the Nadir Adapter. The workflow will be the same for NN3 NN4 NN5 M1. Hope you are not talking about the R1/R10 Nadir Adapter Use.

Then you have to look at this one:http://ge.tt/4uLm9Mb

Using the Nadir shots in PTGuiPro, you can mask out the tripod once and then plug the mask into all other pics. Then you can import the Nadir shots into your workflow.

Heinz

Heinz