Ad
Ad
Ad
Pages: « 1 [2]   Bottom of Page
Print
Author Topic: Where is the best place to pivot the camera?  (Read 5455 times)
BartvanderWolf
Sr. Member
****
Offline Offline

Posts: 3758


« Reply #20 on: August 02, 2014, 05:41:47 PM »
ReplyReply


Yes, that's exactly what I asked, what end of the stick, not the meaning of the phrase/expression ...

In addition, for your edification (since you seem to like referencing other's achievements) ...
« Last Edit: August 02, 2014, 06:14:08 PM by BartvanderWolf » Logged
Isaac
Sr. Member
****
Offline Offline

Posts: 2890


« Reply #21 on: August 02, 2014, 07:37:22 PM »
ReplyReply

Yes, that's exactly what I asked, what end of the stick, not the meaning of the phrase/expression ...

Actually, "exactly what [you] asked" was -- "What stick?"

(Read "Bart may see a thousand unacceptable mismatches..." as "Peter may be ignoring a thousand unacceptable mismatches...").
Logged
Misirlou
Sr. Member
****
Offline Offline

Posts: 657


WWW
« Reply #22 on: August 04, 2014, 05:46:39 PM »
ReplyReply

I shot a pano sequence inside a cathedral recently. Had a lens/camera combo that I had never bothered to check for nodal point, so I just rotated about the tripod screw on the body. Looks fine with objects at appreciable distance, but I cant get the nearby pews to stitch well at all. So in that case, not considering nodal point ruined a really, really nice pano shot.

Edit: This would have helped tremendously:

http://gregwired.com/pano/pano.htm
« Last Edit: August 04, 2014, 05:48:50 PM by Misirlou » Logged
BartvanderWolf
Sr. Member
****
Offline Offline

Posts: 3758


« Reply #23 on: August 05, 2014, 02:06:01 AM »
ReplyReply

I shot a pano sequence inside a cathedral recently. Had a lens/camera combo that I had never bothered to check for nodal point, so I just rotated about the tripod screw on the body. Looks fine with objects at appreciable distance, but I cant get the nearby pews to stitch well at all. So in that case, not considering nodal point ruined a really, really nice pano shot.

Hi,

Depending on the exact scene layout, maybe something is salvageable, but it will probably take a significant manual editing job to pull it off.

As I said earlier, one can either minimize parallax errors in the foreground, or in the background, but not both at the same time. So you can do one stitching operation, while only selecting background features to place the control points on. Then do another stitching operation based on only control points that are around the distance where the initial stitch started showing issues. Then another for a bit shorter distance, and so on. Then do a new stitching operation on all these intermediates, making sure that each image pair has control points at the transition zone between two optimized distances, while probably zeroing the distortion parameters since the distortions were already removed. That would basically only translate and magnify the various layers into optimal position.

In all these operations, also try a good blending program, such as SmartBlend, because it may find a better transition blend between the layers.

This will require a very good Panostitching application (e.g. PTGUI, or Hugin) that allows lots of manual control. Photoshop is probably not able to do what's needed, unless in addition you apply manual masks to each tile that needs to be aligned, prior to the varoius stitching operation runs. That would add even more manual effort.

Even then, there is no guarantee for success. But if time and effort are not an issue, it may be worth an attempt. This obviously is not something one wants to do when time is of the essence, like having to meet a deadline for a client (who is also not likely willing to pay for your wasted time).

Quote
Edit: This would have helped tremendously:

http://gregwired.com/pano/pano.htm

Yes, or something sturdier for heavier cameras, to reduce vibration blur. Usually, the optimal No-Parallax settings will result in a center of mass of camera/lens combination that is significantly offset from the center of the tripod, so vibrations may become magnified rather than damped. Also, not using the multi-row setup when a single row setup is sufficient, may help to get lower vibration risk.

Cheers,
Bart
« Last Edit: August 07, 2014, 03:23:34 AM by BartvanderWolf » Logged
Isaac
Sr. Member
****
Offline Offline

Posts: 2890


« Reply #24 on: August 05, 2014, 09:23:32 AM »
ReplyReply

…also try a good blending program, such as SmartBlend…

Oooo! That looks interesting!
Logged
BartvanderWolf
Sr. Member
****
Offline Offline

Posts: 3758


« Reply #25 on: August 05, 2014, 09:47:33 AM »
ReplyReply

Oooo! That looks interesting!

It is!

SmartBlend is really smart in performing miraculously effective blends, but the impossible still remains that, impossible. It is also no longer being developed it seems, so there's no 64-bit version available, and it therefore depends on also very clever front ends to feed it the optimized (for distortion and light fall-off) projection solution piece by piece.

There are others as well, like Enblend, but they all have (besides their strengths) some sort of drawbacks to offer as well. SmartBlend is an overall good performer, and also has some parameters that can help it to do even better for certain scenarios. So if a Stitching program is capable enough to allow to adjust the command line it sends to SmartBlend, most things will come out relatively well.

Cheers,
Bart
Logged
Isaac
Sr. Member
****
Offline Offline

Posts: 2890


« Reply #26 on: August 05, 2014, 11:21:47 AM »
ReplyReply

So if a Stitching program is capable enough to allow to adjust the command line it sends to SmartBlend…

Otherwise I suppose it might be possible (Hugin) to dump intermediate files and manually adjust the command line…?
Logged
BartvanderWolf
Sr. Member
****
Offline Offline

Posts: 3758


« Reply #27 on: August 05, 2014, 12:01:14 PM »
ReplyReply

Otherwise I suppose it might be possible (Hugin) to dump intermediate files and manually adjust the command line…?

Manual is always possible, but I seem to remember that Hugin can directly utilize SmartBlend, but maybe that has changed (I haven't used Hugin for a while). I just checked, and SmartBlend is mentioned in the help file, but I think one will have to Google for instructions on how to integrate (maybe change the preferences to the optional blender, and adjust parameters?).

Cheers,
Bart
Logged
wolfnowl
Sr. Member
****
Offline Offline

Posts: 5791



WWW
« Reply #28 on: August 07, 2014, 01:37:30 AM »
ReplyReply

Hi,

The best point is the center of the Entrance pupil (AKA No-Parallax Point or NPP) of your lens.

Cheers,
Bart

This being the 'Beginner's Questions' forum, Bart's answer is the best one. Yes, you can get around parallax issues in post, but the 'best' way is to avoid them in the first place. Since that varies from lens to lens, you'd really need to invest in a nodal head for your tripod. Several companies make them, at different price points, and then you'll have to experiment to find the right position for a given camera/lens combination.

Mike.
Logged

If your mind is attuned to beauty, you find beauty in everything.
~ Jean Cooke ~


My Flickr site / Random Thoughts and Other Meanderings at M&M's Musings
Pages: « 1 [2]   Top of Page
Print
Jump to:  

Ad
Ad
Ad