Panorama vs Stitching

[PaulEC]

Usually I find that the Panorama tool works well, but (and I do realise it's called a Panorama tool!) it doesn't do so well if you try to stich several flat images together. (For example, several A4 scans of a larger document.) Sometimes it works, but sometimes the result is distorted. It would be really handy if there was an option to tell the Panorama tool that the original images are flat ones that need to be stitched, rather than actual panoramic images. Currently the tool seems to try to "correct" distortion that isn't there.

[i5963c]

Hello @PaulEC,

Unfortunately, little (actually nothing) is known about how the internal stitching algorithms in Affinity Photo work (projection system, ghosts removal, lens corrections, exposure equalizer, perspective, masking, parallax corrections, ...). In Affinity Photo's panorama tool, all this is processed fully automatically, without user defined parameters. Of course, this is one of the strengths of this tool. At the same time, it's also one of its weaknesses...

I'm unsure about what you mean precisely with 'flat images'.

However, if the purpose is just to 'stitch scanner images', I wonder whether that can't be achieved manually by 'precisely positioning the different scans' on a larger canvas?

I fully agree that such manual procedure is less user-friendly than something that works automatically, but you might probably reach your results faster with such manual process than via 'trial and error' with an automated tool?

 

[PaulEC]

2 minutes ago, i5963c said:

I'm unsure about what you mean precisely with 'flat images'.

If you have an A4 scanner and need to scan something that is bigger, say a painting, (A3, A2, some non-standard size etc) you have to scan it in sections, then stitch them together. You can do it manually but, especially with larger originals, it can be quite tricky to stitch them accurately. It's not a big deal, I just think it would help to have a few options like you get in some other panoramic/stitching software. 

 

[i5963c]

Thanks for reply.

OK, I understand better now.

In the meantime, I did some quick searches, and I noticed indeed that some panoramic tools seem to provide such 'flat image' functionality as well.

As I said, the internals of the panorama stitcher in Affinity are unknown, and there is currently (almost) no way to influence the process. I was preparing a feature request for some other enhancements of the panorama tool, hence I was interested in your thread as well.

[i5963c]

Just something that came to my mind when considering the need to scan A3 or A2 sized documents with an A4 scanner. Not to downplay this feature request, but probably just a practical suggestion / option(*).

I believe that scanning an A3 document will require at least 3 A4 scans, for each A2 document it's even 9 scans.

In the end, it might be much simpler to just take a picture with a digital camera of the A3 or A2 document. Of course, some specific requirements (e.g. special resolution specs, but unknown to me) might still enforce the use of a scanner?

With a good prime lens and e.g. a high-res camera, you get tack sharp images of the documents in a fraction of the time spent on scanning and stitching. Even a moderate lens and 'normal' resolution camera will most likely provide sufficient detail in the final image.

 

(*) I'm currently in the process to digitize my archive with +3000 old color slides. Originally, I started this project with a photo scanner, but the scanning process took way too long (also considering the required scan resolution). A while ago, I did some research on the topic, and discovered that it could also be done with a camera, a macro lens, a tripod and a light box. Because of the repetitive, high volume work, I also made a temporary 'construction' to freeze the relative positions of camera, light box and slides. For low volume work, this is of course not needed. For larger documents (like A3/A2), a camera and a lens could be sufficient.

I could easily process +150 slides per hour (including blowing away some occasional dust). Such throughput was simply impossible with my scanner...

Currently, still busy with post processing the bunch of pictures😠... But, this effort would be the same with stitched scans.

[PaulEC]

Thanks for your input. You can certainly use a good quality camera, but it's quite an effort to set it up, (preferably without key stoning - that then has to be corrected!) and to light it evenly. I'm often scanning artwork that needs to be evenly lit, high res. and as sharp as possible. I suppose an A3 scanner would help; but a half way decent one is way beyond my budget! 😐

[Old Bruce]

4 hours ago, PaulEC said:

I'm often scanning artwork that needs to be evenly lit,

And that is harder than you'd think.

[DeadArtist]

I scan my art. I have a ccd scanner that I bought in the $500 range and it works well. My question is, should I go for a minimal amount of scans ( right, left or multiple scans (right, middle, left)? Is it better for the system to have more to work with or less. 

[Old Bruce]

11 hours ago, DeadArtist said:

I scan my art. I have a ccd scanner that I bought in the $500 range and it works well. My question is, should I go for a minimal amount of scans ( right, left or multiple scans (right, middle, left)? Is it better for the system to have more to work with or less. 

More is better. One caveat is if the art is made up of highly regular geometric shapes, or has big monochrome areas. 

I try for 30 to 50 percent overlap when shooting my photos for panoramas.

[Chris Kangsan]

On 10/25/2021 at 3:56 AM, PaulEC said:

Usually I find that the Panorama tool works well, but (and I do realise it's called a Panorama tool!) it doesn't do so well if you try to stich several flat images together. (For example, several A4 scans of a larger document.) Sometimes it works, but sometimes the result is distorted. It would be really handy if there was an option to tell the Panorama tool that the original images are flat ones that need to be stitched, rather than actual panoramic images. Currently the tool seems to try to "correct" distortion that isn't there.

I also criticized Affinity Photo for the same thing. The programmer developers completely forgot to add flat/linear axis panorama stitching algorithm to their software. If I were a better programmer, I would apply to work Serif to fix their most obvious programming issues, but I'm not a good programmer. They must fix a lot of bugs in this most current update as well as add more combative and challenging tools against Photoshop and Illustrator. I love Affinity but they need to step up their game against Adobe and start thinking outside the box instead of the within the box with a 10ft pole. I hope they fix the linear photo stitching algorithm soon.

[Archangel]

On 10/25/2021 at 11:56 AM, PaulEC said:

Usually I find that the Panorama tool works well, but (and I do realise it's called a Panorama tool!) it doesn't do so well if you try to stich several flat images together. (For example, several A4 scans of a larger document.) Sometimes it works, but sometimes the result is distorted. It would be really handy if there was an option to tell the Panorama tool that the original images are flat ones that need to be stitched, rather than actual panoramic images. Currently the tool seems to try to "correct" distortion that isn't there.

Sounds like a job for Serif's Scan Stitch and Share. Unfortunately, it was a legacy product and has been discontinued. It was limited to 300dpi and only existed on Windows. You might be able to get a copy on Ebay.  However, as it was based on Serif's Panorama Plus then serif might be able to tweak Affinity Photo's Panorama algorithms to provide a similar function.

Nuance PaperPort may have offered a similar function, but I cannot remember.

[PaulEC]

11 hours ago, Michael S Harvey said:

Sounds like a job for Serif's Scan Stitch and Share.

Thanks for that. I did use Serif's Scan, Stitch and Share many years ago! (I could be wrong, but I think it came free with an old version of PhotoPlus.)

Actually I did need to stitch some screen grabs a couple of days ago, 'tried using the Panorama tool in APhoto, but, again, I got a slight horizontal distortion. As it's not easy (possible?) to correct horizontal and vertical distortion (not perspective!) separately in APhoto, I used Microsoft ICE instead, which has options for planar motion, and it did the job perfectly!

[MAMS]

Just started using Affinity. The very first thing I tried to do is trying to stich images together (NO PANORAMA!) does not seem possible.

Very dissapointed in Affinity.

[Hangman]

@MAMS, welcome to the forums...

These tutorials may help...

 

[John Rostron]

Hello @MAMS, and welcome to the forums.

How do your requirements differ from stitching a panorama together? The Photo panorama has worked for everything I have thrown at it.

John

[tvgm2]

I ran across this today in Photo 2.1.1 today while trying to stitch together parts of a representation painting taken by my phone on a tripod while raising the painting part by part on an easel. It was only 1 column of photos.

If the background behind the painting was blurry it did well enough. However if something is in the same focus plane as the your subject, it doesn't seem to know what to do and results in the subject bending or being stretched super wide.

I was able to fix this by cropping each part of the painting.