Panoramic issue - DPChallenge Forums

Canon EF 28-135mm f/3.5-5.6 IS USM

12/14/2004 06:57:02 PM · #1

I've made some panoramics and i'm having a problem with the exposures it seems when i stitch the photos the have some parts that are darker than others, especially on the places they stitch. Can anyone help me, is it the way i took the photo or can i make a correction with software?

BikeRacer

Canon EOS-300D Rebel

12/14/2004 07:00:51 PM · #2

what software are you using to stitch?

Canon RF 24-70mm f/2.8 L IS

12/14/2004 07:01:44 PM · #3

the panoramic factory

kirbic

Canon EOS R5

12/14/2004 07:05:25 PM · #4

It's not unusual, especially if all the setings weren't locked. the camera may have changed exposures from shot to shot. You also might be seeing the natural light fall-off of the lens if you shot at ver wide angles. All lenses have this to some extent.
A third possibility is changing polarization of the sky, which does vary naturally, and which will be very pronounced with a polarizer in place.
Even relatively noticeable changes can be usually be corrected in software. When you stitch, you need to output the final file in a layered format, such as Photoshop (.psd). Then adjust each one to closely match one that you choose to be a "reference image". Next, use masks to adjust the images selectively to make up for remaining mismatch.
The above proces does take some practice, but once you get the hang of it, you'll be surprised how well you can match.
As a final note, some software claims to be able to ccolor match automatically, but I've never been satisfied with the results.

BikeRacer

Canon EOS-300D Rebel

Canon EF 28-135mm f/3.5-5.6 IS USM

12/14/2004 07:05:51 PM · #5

well, you should be able have it automatically compensate individual exposures - they call it exposure matching. sometimes the problem is vignetting, and PF can fix that too - i think they call it brighness falloff. make sure you have the latest version.

12/14/2004 07:10:27 PM · #6

Originally posted by BikeRacer:

Is there any tutorial i can go with?

Canon EF 28-135mm f/3.5-5.6 IS USM

12/14/2004 07:10:56 PM · #7

Originally posted by BikeRacer:

I'm using version 3.0 is it the latest or don't you know this?

BikeRacer

Canon EOS-300D Rebel

12/14/2004 07:13:13 PM · #8

i think they're up to 3.3 - //www.panoramafactory.com/

Message edited by author 2004-12-14 19:13:32.

Brad

Olympus OM-D E-M1

Olympus 40-150mm f/2.8 PRO M.Zuiko

12/14/2004 07:30:22 PM · #9

Hi Frederico,
I have dabbled with panos a bit and through trial & error (mostly errors), have figured out what seems to work.
1) Don't use a polarizer if the sky is being shot. Light & dark bands will give you fits.
2) Don't shoot in a wide-angle mode, as the curvature makes it difficult to stitch using basic stitching tools.
3) Try and overlap the shots around 50% to minimize distortion.

Here is a shot I did this past Sunday from a friend's house about 2 miles from mine:
A View of my Valley (click on screen image to see panoramic)
It is four 2240x1680 shots stitched together using the Olympus Camedia software, horizon adjusted and cropped to 3000x800.
Little else was done other than NI for noise in the sky and USM applied to the lightness channel in Lab color mode.
The Camedia software has a setting for exposure compensation to help adjust for light/dark areas and seemes to do well.
HTH

Message edited by author 2004-12-14 19:30:57.

Olympus 40-150mm f/2.8 PRO M.Zuiko

12/14/2004 07:34:22 PM · #10

Originally posted by BradP:

Great pano. And where can i get that software?

Brad

Olympus OM-D E-M1

12/14/2004 07:46:22 PM · #11

Originally posted by Discraft:

Great pano. And where can I get that software?

What you have now is actually probably better. The newer Camedia software (v 4.X) will only support panoramic mode if it was taken with a camera in pnoramic settings.(weird) The 2.5 version originally came with the Olympus E-10 and many other digicams I assume.
The Panoramic Factory software from what I remember (demo) functioned very well, and was much more suited to genertating a pano than the Camedia software.
I still think it has more to do with how you are shooting, at what focal length and how much overlap you are allowing yourself.
Any examples?

Canon 12x IS USM (S3 IS built-in Lens) -- 36-432mm (35mm EQ)

12/14/2004 07:58:28 PM · #12

I'm making the upload of the images when they are availabel to see i'll let you know. I'll put the two photos i took and then the result of the panoramic shot. The original photos aren't the greatest capture. but these are just some examples i have another shots that are better but they are going the same way as this one.

GeneralE

Canon PowerShot S3 IS

12/14/2004 07:59:58 PM · #13

My Canon S1 IS came with stitching software for both PC and Mac, but I haven't tried it yet. You can set the camera in a special mode which bot only locks the exposure, but after you shoot a frame, it shows part of it in the viewfinder to help guide the overlap for the next frame. These frames are named differently from the usual stills to make it easy to find them with the stitching software.

If anyone's used this software, I'd like to know if it's worthwhile installing it.