Photomerge unable to combine images

[Kerrowman]

Hi all,

I am having an issue with Photomerge, that I have seen other people on the Adobe forum bring up, but I can't see how to implement their suggestions.

I have a stack of 25 JPEG images, obtained first as screen grabs from a video of a land survey, and then converted from PNGs to JPEGs.

The steps I have used are:

Open all the images in PS
Go to File/Automate/Photomerge/Browse
Select 'Add open files'
It comes up with a message saying' Documents must be saved before they can be merged'.

If I save some of the files as PSDs, then select those using 'Browse' (see pic), again nothing happens.




If I try another route of opening one of the images first then
In Photomerge select the remaining using 'Browse' so they show in a list in the window
Click 'Ok'
Nothing happens.

I have seen a post on another forum saying that removing the EXIF data might help but I'm not sure how to do that at the moment or if it would work here.

I'm using a Mac Mini with PS version 23.2.0

Any thoughts would be helpful.

 

[thebestcpu]

Hi @Kerrowman
I am assuming that you are trying to create one continuous image since that is the purpose of the Photomerge command.
It is unclear to me if you have 25 images in a full linear program or if you are trying to create a full xy grid of images patched together from your description.

If any of the images being merged are changed in any way before the merge process, they must be saved to disk as their own file before the photo merge.
I don't remember the details, so I suspect it is to protect your modified images.

So once you are only merging files that have had no edits right before merging, you should not get that warning message. That does not mean you don't have other issues to address yet that should get you past the first problem.
Hope that helps

Also, when you say "nothing happens," does that mean it is giving you the same message about saving the files, or is it a different issue?
John Wheeler

 

[Kerrowman]

I am trying to create an orthophoto of an area of land using screen grabs taken at regular intervals from a video with a -90 degree gimbal angle (straight down). I have since found that using regular images from a phone, camera or drone works fine, so it must be the fact that the screen grabs contain little or no EXIF data? It seems Photomerge needs some of that to do its thing.

I am going to get around the issue by using a still image capture on the flight path and spacing them accordingly with about 25% overlap, forward and sideways, to give Photomerge something to get its teeth into. I just hope it won't mind working through 60-70 images to build its composite using 'Reposition'.

 

[Kerrowman]

Having said that I had sorted it, I have tried the process with some drone images and again it does nothing, but will work with iPhone camera images.

Here is what I get when I try to merge files already open:



I have tried saving each as a jpg again and that makes no difference, as does browsing for them.

This is clearly a deeper problem and must have something to do with their metadata.

 

[thebestcpu]

Hi @Kerrowman
I am pretty sure the error you getting is accurate. And yes there is something different about the files yet it could be something else than the metadata.
You will get that flag if anything is changed with the image.
One simple way to change the image on input is through embedded color space.
If you have your "Edit > Color Settings" set so that if the incoming file has a different color space than your working color space, there is an option to automatically convert to your working color space. That change is flagged in Photoshop, and you will not be able to do Photomerge until you save the file with the changed color space.
To get around this issue without having to save the images back to the disk, change your settings to "Preserve Embedded Profiles."
The image below shows the settings I use and note the setting at the red arrow.
Also, I always have all the flag options set to let me know when an image comes in in a different color space than my working space so I can be alerted to that fact.



This may or may not be your issue yet I could reproduce your problem when my files were converted from the embedded color space to the working color space and without saving back.
Hope this helps you out.
John Wheeler

 

[Kerrowman]

Thank you for the suggestions.

I found a solution today which is to convert all the drone jpg files to heic files as a batch using the Quick Action option and then Photomerge is happy to work with them as normal. Why that works is not clear, but it may be that the file type conversion also converts to the working colour space and that might be, as you proposed, the real issue.

However, having sorted that the Auto merge option leaves big gaps despite the images having 40-50% overlaps. The ‘Reposition’ option assembles a few blocks of images widely spaced out on a big canvas and I don’t know how to move them manually.

I step forward, one and a half backwards