Merging problem

[ar14]

As you can see there are six lines in this panorama where images are merged. Does anyone know how can I avoid this? I have another night panorama and it's the same thing.

I used Aperture priority mode (f5,6) but forgot to use exposure lock, so not all images were shot with the same shutter speed. In the first two images, the shutter speed was 8 sec, in the next four 10 sec and in the last 13 sec.
Although, as you can see, the largest difference appears where two images with different shutter speeds come together, there are still slight differences between the middle 4 images which were shot with the same shutter speed. Why is that?

Just a side note: how does aperture affects long exposure shots? Would these shots that I took be sharper if I used a smaller aperture?

Thanks for your help

[wulf]

How are you merging the images? Manually, with a program like Photoshop or The Gimp, or with an autostitching program?

Wulf

[PhotoNewt]

The answer to your question is on your post; by using aperture priority you allowed the camera to set different exposures on each image causing this problem. Panos MUST be shot using a tripod, manual focus and manual exposure (not changing any between shots) to avoid this kind of problem.

Panos should be shot fairly fast to avoid changes in the light or the scene. The problem of shooting after sunset is the light will fade very fast, obtaining even exposures of several panos becomes very difficult. This is likely the reason why even at the same shutter speed your photos don't have the same exposure so there is some difference between them.

Your third point regarding aperture; for landscape photography work, you should use the highest f-number available (smallest apertures), on a dSLR is between f/16-f/22. This will maximize your DoF making more of the scene to fall into acceptable focus from front to back. This is true for landscape panos or any other regular landscape work.

[ar14]

I used photoshop.
How can I remove them? If it's possible of course.

Thanks PhotoNewt.
I am kind of new to photography and I'm often still forgetting the obvious stuff. This was my first time using a tripod

[inkista]

Originally Posted by PhotoNewt

...for landscape photography work, you should use the highest f-number available (smallest apertures), on a dSLR is between f/16-f/22.

Actually, you probably don't want to stop down farther than f/16, because diffraction will begin to affect the sharpness of the photo. Just FYI. Film didn't show it, but it shows up with the ever-decreasing pixel dimensions we've now got on sensors.

Have you tried restitching the images with something like Autostitch? or Hugin? They include software for blending over any visible seams.

One last thing--don't forget when shooting panos to make sure you set the White Balance to a non-auto mode--that can also color shift your images between shots.

[PhotoNewt]

Originally Posted by inkista

Actually, you probably don't want to stop down farther than f/16, because diffraction will begin to affect the sharpness of the photo. Just FYI. Film didn't show it, but it shows up with the ever-decreasing pixel dimensions we've now got on sensors...

You are certainly right on this point. Keep thinking about film photography!

[wulf]

See this thread on hand stitching a panorama.

Wulf