Stitching multiple images to increase resolution

DMJ

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Yes, I have used PTGui for stitching 16mp images but you are not increasing the resolution, only creating a bigger image. There is the new Photshop's "Super Resolution" tool that actually does increase the resolution of the images.
 

Chan Tran

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Yes, I have used PTGui for stitching 16mp images but you are not increasing the resolution, only creating a bigger image. There is the new Photshop's "Super Resolution" tool that actually does increase the resolution of the images.
Then we need a definition for resolution then. Not that I disagree with you but in this case the term resolution isn't clear.
 

wiltw

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I agree with Charlie. The way I see it,
  1. if you start with one 2000 x 3000 image, stitch it witih two more 2000 x 3000 images, so the merged image is 2000 x 9000, this does result in a single 2000 x 9000 'higher resolution image' which has more pixel count resolution than the starting 2000 x 3000.
  2. OTOH, I understand fully that if I have an image of 200 line pairs per millimeter, stitching it to two more images of 200 line pairs per millimeter ends up with one composite 2000 x 9000 image that has 200 line pairs per millimeter of detail, no better detail.

So the ultimate detail content of #2 is no better than a single image (out of the triplet of images), but the composite does have more total pixels than the single 2000 x 3000 image of 200 line pairs per millimeter, and 3x the total detail of a single image
Semantics

Back to OP question. This is a composite photo of two shots taken with Canon G2 which produces 4MPixel images. Cashel, Ireland, shot in 2004


This photo was result of two very quickly taken shots on the side of a highway, hand held and not on tripod, two grab shots not carefully composed with careful angle shift at the lens node. I forget what I used for stitching, but it was a public domain utility. In short, one does not necessarily need to be meticulous and methodical in taking the shots for a stitch composite, but understanding that one needs 'identical exposure' with no differences due to automated exposure control helps. the more care and understanding in the planning can improve the result obtained.
 
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nmp

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You can improve the effective resolution if you use a long lens to take multiple images and get a single wide angle shot out of it by stitching as opposed to taking one shot with a wide angle lens. ACR Super Resolution does a similar thing by guessing new values between captured pixels.

:Niranjan
 

warden

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Anyone tried this with a lo-res camera, i.e. 6-12 MP? If so, any tips?
You can make an enormous image by stitching 6mp images together, just make sure you are consistent with the individual images (exposure, focus, elevation, etc) and you'll be off to a good start. Photoshop and other apps have quality tools available for stitching images together but they require experimentation to get the hang of it.
 
OP
OP

Horatio

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Thanks to all. I was thinking about getting a larger image overall without having to up-rez a single image.
 

MattKing

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"Resolution" is probably better used to describe how much information is packed into a defined area, but it seems to also be used as well in place of total information available.
 

sfphoto

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My method to stitch:

1) make 2 photos with:
- same manual exposure setting and the same white balance setting (not auto)
- overlapped +/-20 percent

2) duplicate both image files and reserve

3) open left one in PS/PSE then select canvas size, in dialog window place imaage at center left then overall new size to double the original width

4) open right image then drag to empty right hand spot in your canvas, move until happy with position

5) choose box select tool set to 30px feather and select a small section of the overlapped portion, then delete

Re-do if improvement is needed.

Images made LEVEL at a distance with 'normal' focal length setting/lens work best.
Grid lines in finder help composition.
Wide angle, esp. if close require camera rotation on the nodal point.

If you are going to stitch several, Hugin for Mac is free and uses same PTools engine as PTGui, just does not have such a nice G.U.I.
If you do not have PS/PSE the latter is very inexpensive on CD and PSE v8 or older does not 'Phone Home'.

For repro work one needs to set up a system for moving the camera parallel to the subject.
 

grat

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The "original" gigapixel image was taken nearly 20 years ago with a 6 megapixel camera, and stitched 196 images together:

https://www.tawbaware.com/maxlyons/gigapixel.htm

And then he did another one:

https://www.tawbaware.com/maxlyons/gigapixel2.htm

As for the resolution aspect, if you're digitizing negatives, zooming in farther and stitching will produce a final image that is a higher resolution "scan" of the negative than a single picture. Using my Epson scanner, I can produce a 3200 PPI scan of a medium format negative. In theory, it should be capable of 6400 PPI, but as a rule, I don't go higher than 3200. Using my DSLR, and stitching, I can produce an image with a resolution of about 6800 PPI from the same negative.
 

DMJ

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Impressive. Around that time I got my first digital camera which I still own, a 5mp Panasonic Lumix TZ1
 
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