Sunset Panorama

Well, here is the new edit. I have calmed down the highlights so there isn't so much clipping on the histogram, the boat on the right is removed, and no curvy shoreline. What do you think? Better, worse?


Original Edit

http://i61.tinypic.com/kbefwy.jpg

New Edit

http://i62.tinypic.com/2dv5ydf.jpg

Rita - nicely done. Let me make a couple of suggestions that might make doing a pano easier next time.

1. Shoot in manual mode; but establish your exposure by sweeping the scene and determine an "average" exposure for all your shots. That way you won't have to balance the exposure between the shots and the blend will look more natural.

2. Once you have focused, disable autofocus. Again, that way each shot will have the same aperture and lens distortion impact. Again, this will lead to an easier merge when you assemble the shots in Photoshop.

3. Make sure you do lens correction while in ACR. That will remove distortion and the various shots will line up better when you merge them.

4. The curvature in the foreground is due to you rotating your camera on the tripod mount centre, rather than the optical centre of the lens. There are two ways to fix this; the easy one is to trim this in Photoshop. The more difficult way is to get a nodal plate for your camera and determine the optical centre of the lens for a number of different focal length settings. You then use the nodal plate to offset how your camera rotates on the tripod and this eliminates the curve of the subject material that is close to you. Needless to say, this is a bit of a time consuming exercise that has to be repeated (and recorded for every lens that you use).

Manfred, thank you for the suggestions I will keep these for my next attempt. I almost always shoot in manual but never thought about taking an "average", probably because that is totally new to me :) For my focusing I have recently moved the focus to a button on the back of my camera rather than having it on the shutter button. For this series I focused once and left it at that, is that the sort of idea you mean in #2? I will read up on nodal plates as these are completely foreign to me.

Hi Rita,
I was just looking at the misalignment of the horizon under the sun (or where it used to be) and wondered if you levelled the horizon in each shot before stitching?

Quote:

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Originally Posted by Rita

Manfred, thank you for the suggestions I will keep these for my next attempt. I almost always shoot in manual but never thought about taking an "average", probably because that is totally new to me :) For my focusing I have recently moved the focus to a button on the back of my camera rather than having it on the shutter button. For this series I focused once and left it at that, is that the sort of idea you mean in #2? I will read up on nodal plates as these are completely foreign to me.

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This is what I use along with an L-bracket:

http://www.kirkphoto.com/Long_Rail_Plate__LRP-1.html

Hi Rita,

Ummmmm?

The first thing that strikes me is that you have changed what would have been an area of intense light of the sun which would be yellow to an area of 'blue tone' which does not tie up with the reflection directly under. I'm not sure what you use for PP or skill levels but personally I feel that the original posted although the bright area was clipped was far better.

For me this crop works as would one that includes a part of the foreshore on the right, but this is up to personal taste of course.

As for the stitching anomaly at the centre here's a crop of what I was referring to, look dead centre in area from sun to horizon.

http://i62.tinypic.com/von0u8.jpg

Please note that my comments are purely in the interests of assisting you to take this first great panorama of yours to an even higher level with what you have:)

Grahame

Greg, I did not straighten before stitching. I did it after. There is a good lesson in there for me :)

Manfred, thank you for the link. Now I have an idea of what it is.

Grahame, I am most grateful for your help! Wow, I looked and looked and looked for that one under the sun and I couldn't see it at all. I see it now in your crop and I will work on that. I also see what you mean by me darkening the sun itself and it not matching up with the reflection. I burned this area so I will fix that. For PP I am using photoshop cc but I am just learning it :)

Quote:

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Originally Posted by GrumpyDiver

Rita - nicely done. Let me make a couple of suggestions that might make doing a pano easier next time.

. . .

4. The curvature in the foreground is due to you rotating your camera on the tripod mount centre, rather than the optical centre of the lens. There are two ways to fix this; the easy one is to trim this in Photoshop. The more difficult way is to get a nodal plate for your camera and determine the optical centre of the lens for a number of different focal length settings. You then use the nodal plate to offset how your camera rotates on the tripod and this eliminates the curve of the subject material that is close to you. Needless to say, this is a bit of a time consuming exercise that has to be repeated (and recorded for every lens that you use).

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I am afraid I don't understand this statement. Firstly, there seems to be a genuine curvature of the shoreline, as indicated by the wave motion the water, which is not introduced by the way the photograph is taken. Perhaps Rita can confirm or contradict this.

I understood that the reason for rotating the camera about the no parallax point of the lens is that two points in the scene which line up with the point of view in one shot should stay lined up in the overlapping shot. With a distant scene like this one, the error is likely to be small anyhow so that this is not so important. There seems to be some confusion about where the no parallax point is in relation to the nodal points. A lens has a front nodal point and a back one, which I think would depend on the focal length of a zoom lens and perhaps on where it is focused as well. What I read on this was a bit ambiguous but it does seem that the no parallax point is coincident with the front nodal point.

Tony, there is a curvature to the shoreline but in the image it has become accentuated. Hope this helps.

Rita, I thought about the geometry of this some more. If you take a photo looking to the left and then take another looking to the right, the perspective is changing because of the different angle of the sensor plane. This exaggerates the curvature of the shore line especially as you were using quite a wide angle lens and probably changed direction a fair bit between shots. I downloaded your file and played with it using perspective warp in Photoshop. With this, I was able to reduce the curvature of the shore line and it made the picture look more natural to me. Without knowing how it looks in real life, I could not be sure how much to correct it.

The image looks fantastic at full screen.

Tony, I am not familiar with perspective warp yet. I would love to see your edit :)

This is my edit. It is not a very big difference but if you look at the two together you can see it. I have not changed anything except the perspective.

This is the first time I have used perspective warp. It was a good exercise for me.

https://farm6.staticflickr.com/5567/...a146c639_o.jpg

Thanks for posting this Tony. Yes, it does make a difference and it looks much closer to the real view. I am too tired now but I will take a look at how to use that tool tomorrow.

Quote:

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Originally Posted by TonyW

I understood that the reason for rotating the camera about the no parallax point of the lens is that two points in the scene which line up with the point of view in one shot should stay lined up in the overlapping shot. With a distant scene like this one, the error is likely to be small anyhow so that this is not so important. There seems to be some confusion about where the no parallax point is in relation to the nodal points. A lens has a front nodal point and a back one, which I think would depend on the focal length of a zoom lens and perhaps on where it is focused as well. What I read on this was a bit ambiguous but it does seem that the no parallax point is coincident with the front nodal point.

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Tony - I can't remember where I got this information, but in my experience, the curvature of nearby straight object disappeared when I started rotating the camera around the optical axis of the camera using the nodal plate rather than just around the tripod mount. It's possible I changed something else in my technique as well.. If I still have the two original images, I'll try to located them; the difference is quite astounding; both involved the railings of the bridge I was shooting from. All I can think of is that the additive impact of parallax is more noticeable as the object gets closer to the camera sensor plane.

In the case of Rita's image, I can't say for certain regarding the shoreline; it just looks surprisingly similar to a shot I took that showed the same effect.

Found it. Note the curvature of objects near the bottom of the image. Both these images are close to 180 degree panos. The camera was rotated on the tripod mount.

Nikkor f/2.8 24-70mm @ f/16 36mm

https://farm4.staticflickr.com/3742/...cd20a8f0_k.jpg


This pano was shot using the nodal plate. Note how straight the railing is.

Nikkor f/2.8 14-14mm @ f/5.6 24mm

https://farm4.staticflickr.com/3785/...9c2be234_h.jpg


If someone has a better explanation; I'd love to hear it.

Manfred, even though these scenes are not as distant as Rita's, I still find it hard to believe that it is the axis of rotation of the camera that makes the difference. In the second one in particular the stitching is so good that I can't see the joins. I would need more information about the individual shots and how they were assembled to understand the difference. Were they put together manually or with an automatic stitching program?

Hi Tony, the image improved with your edit indeed. I use PS CC too but I wasn't aware of perspective warp because I'm still learning. Thanks for mentioning and sharing an edit about it :)

Quote:

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Originally Posted by TonyW

This is my edit. It is not a very big difference but if you look at the two together you can see it. I have not changed anything except the perspective.

This is the first time I have used perspective warp. It was a good exercise for me.

https://farm6.staticflickr.com/5567/...a146c639_o.jpg

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Quote:

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Originally Posted by TonyW

Manfred, even though these scenes are not as distant as Rita's, I still find it hard to believe that it is the axis of rotation of the camera that makes the difference. In the second one in particular the stitching is so good that I can't see the joins. I would need more information about the individual shots and how they were assembled to understand the difference. Were they put together manually or with an automatic stitching program?

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Automatically stitched in Photoshop using Photomerge using the auto setting. I've found that this has always worked best for me.

The first one was done using Photoshop CS6 and the second on Photoshop CC; I don't believe Adobe made any changes to this function between these two versions.

The reason I got the nodal plate is after asking around (may have been here at CiC) that someone suggested that I should be shooting with a nodal plate to fix the "curvature" issue. The images were shot about 6 months apart, i.e. June 2013 and Dec 2013. Camera was set to manual and the shots had around 10% - 20% overlap between the shots on either edge. Other than the lens, the same equipment was used in both shot. Lens correction was done in ACR during the import process; all shots had the same ACR profile applied to them. Basically, same shooting and photomerge technique used in both image used in both other than using a different lens, the nodal plate and possibly a different tripod.

Rita - just to give you more of an idea of the setup I use:

https://farm8.staticflickr.com/7447/...dcf17c1f_b.jpg

This is my camera, on an "L" bracket which is attached to the nodal plate. I've exaggerated a bit; but you can see that the camera sits further back and rotates at a point that is offset from the tripod mount.

This looks huge Manfred :eek: Is it the device which is big or your camera? I'm afraid I will have to buy a bigger camera bag in the future :o

Quote:

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Originally Posted by GrumpyDiver

Rita - just to give you more of an idea of the setup I use:

https://farm8.staticflickr.com/7447/...dcf17c1f_b.jpg

This is my camera, on an "L" bracket which is attached to the nodal plate. I've exaggerated a bit; but you can see that the camera sits further back and rotates at a point that is offset from the tripod mount.

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