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View Full Version : Stitching vs cropping a wide angle shot for a panoramic image



HelenClaire
14-06-2015, 10:09pm
Just curious for feedback. Have never stitched photos and was going to learn how, then I got my Canon 16-35mm lens and am now wondering if I really need to stitch. If I compose a picture with the main subject in the middle I can crop in PP to a 3:1 ratio and hey presto I have my panorama. So my question is are there any benefits to stitching over my cropping method?

farmmax
14-06-2015, 11:59pm
Stitching adds pixels from numerous photos so you have lots and lots of pixels to play with, whereas cropping takes even more pixels away from a single photo. The larger the number of pixels in the photo, in theory the better the quality of the image and the more leeway you have to edit the photo.

If you ended up with a stunning cropped photo which you wanted to enlarge into a large canvas on your wall, the file probably wouldn't be high enough quality to produce a good quality enlargement, then you would kick yoursel :D

Mark L
15-06-2015, 12:07am
Even with your new lens you may want to go wider sometimes. Going to the Grand Canyon soon? Also using the lens in portrait mode may give you more of what you want and thus you might need two or three photos to stitch (I know what I mean).
FWIW if you want to stitch, this is a very good free software ...... http://research.microsoft.com/en-us/um/redmond/projects/ice/

arthurking83
15-06-2015, 12:08am
Cropping means lost pixels(data) .. so resizing(upwards) is more restricted.

Stitching means adding pixels(data) .. so resizing(upwards) is less restrictive.


eg. using the same camera with an arbitrary pixel dimensions of 6000x4000 .. and say you have a scene similarly framed for both methods:

* with the crop method, because you are cropping your final pixel dimensions will be less than 6000x4000 .. more like 6000x2000 or something like that.
* with the stitching method, because you are taking multiple images(lets just say 2 for the sake of easy maths) .. for an overall image you may have 12000 x 4000 pixels to play with.
.. but in reality most stitched situations will produce some small errors which results in the programs advising that a crop to smaller dimensions than you otherwise would have had as a maximum.
This may be something like 10000x3500 or something like that.
Either way 10000 x something is still considerably larger than 6000 x something! .. allows you more freedom for printing or whatever.

FWIW: I generally crop, as the D800 has pixels to spare .. but if you try to explain that to the anti hi res camera brigade .. they just wont have it! :p
The reason I crop is simple .. as you describe, I have an UWA lens that allows you to see more .. but in my situation I have the Sigma 12-24mm lens.

Don't get me wrong tho, I also do stitches where I can .. if I can, subject to time constraints and conditions and other variables like that.

My largest attempt at a stitched pano was a portrait orientation 15 image 360° view of Lake Eyre. The resultant pano is 44733x6933. I made sure I had a fair amount of overlap between each image too tho.
The D800 has pixel dimensions of 7360x4912, so 44733/4912(about 10 images) means that I basically wasted about 5 of those images for the security of a cleaner transition from one image to the next(overlap).
I don't remember that the stitch took a long time to create(using PTGui) .. but it takes any(and all) image viewing software an eternity to load the 2Gig tiff file for viewing.

If I had to declare a preference for either method .. my head would probably explode from the endless loop such a topic would create.
I prefer both methods.

HelenClaire
15-06-2015, 12:20am
Thanks guys for the feedback above. Really appreciate your wisdom. Food for thought :umm:

ameerat42
15-06-2015, 10:43am
Thanks guys for the feedback above. Really appreciate your wisdom. Food for thought :umm:

Fine, however, I disagree with your original premise, highlighted in the quote below:


Just curious for feedback. Have never stitched photos and was going to learn how, then I got my Canon 16-35mm lens and am now wondering if I really need to stitch. If I compose a picture with the main subject in the middle I can crop in PP to a 3:1 ratio and hey presto I have my panorama. So my question is are there any benefits to stitching over my cropping method?

Your method simply produces a crop with a wide (sometimes called "panorama") aspect ratio. A panorama is a wide field of view of something. (Actually, see better description in 1st sentence here). (https://en.wikipedia.org/wiki/Panorama)

You have the means of capturing the wide field, particularly with the 16mm end of that lens.

Just my 2 "benefits" that stitching has over cropping: 1) potentially wider field than the lens alone can give; 2) ability to capture more detail in the larger resulting image.

You don't always need to capture more detail, so in many case a single wide-lens cropped image will suffice and be a panorama. My reply was to point out that the "Hey presto!" part
of your method does not always work.

Am(al la AK:D).

- - - Updated - - -

PS: an extra benefit of stitching images: you learn to stitch images. :nod:

Zarniwoop
15-06-2015, 11:13am
Just adding another aspect to this whole stitching versus cropping thing. Remember when stitching you have to ensure that you rotate the lens around the nodal point in order to ensure that you get a level horizon and do not have to adjust the image too much. One way around this is to use a tilt shift lens which will just move in a single plain.

My main thoughts are crop is quick and can really add to not-so-well-composed photo. Stitching takes extra time and may mean more balancing of shots in order to make the photo appear seamless.

Mark L
16-06-2015, 10:14pm
Remember when stitching you have to ensure that you rotate the lens around the nodal point in order to ensure that you get a level horizon and do not have to adjust the image too much. One way around this is to use a tilt shift lens which will just move in a single plain.



So does using your lens a bit wider and cropping closer once you've stitched get over this?
Generally the nodal point won't worry must here. Using manual to get the exposure correct across all of the stitched photo may be more important?

Zarniwoop
16-06-2015, 10:33pm
So does using your lens a bit wider and cropping closer once you've stitched get over this?
Generally the nodal point won't worry must here. Using manual to get the exposure correct across all of the stitched photo may be more important?
Sure getting the exposure consistent across all the shots. If you do not rotate the camera around the nodal point your images will show parallax and be difficult to stitch.
See this article for further information on Parallax. (http://wiki.panotools.org/Parallax)