Thank you muchly for the responses. I will have to sit down and read them carefully, do what's suggested and absorb it all, learn what it means.
Meanwhile I had a thought in the night...
Isn't the crux of my problem my insistence upon getting the mix of photos onto one printout?
Together with letting GIMP decide the pixel size of the printout canvas?
GIMP has decided 180 ppi I suppose because that's the default on my setup when I ask for a new canvas.
Each photo actually has a different ppi because though all taken with the same camera at the same resolution my cutting a part out to use for the passport means I am making a different ppi for each one based on the number of pixels I've had to cut out from that photo - requiring each cutout to shoehorn into 48mm x 33mm. Is that right?
So that 737 x 1072 actually is meant to be a 33x48mm pic with a dots per mm of 22.3 which at 25mm per inch would be something like 558dpi.
So I, for that pic, should tell GIMP I want a new canvas measuring (4 x 558) x (6 x 558) in inches. And so on...
I think I've got that right have I? Learned something there?
I will try that and as I say I will try your suggestions and really learn something, hopefully.
One needs understanding isn't it? Not just blindly doing things. My current understanding is so miniscule. I don't know the difference between a mask and a layer. I don't know what to do, if anything, about 'floating layers', don't know about these alpha channels and whatnot.... don't know nuffin....
later: ah. not so difficult. both of you are simply talking about scaling. and it seems to be the answer. thanks. that way I don't need to make different printouts for each.
GIMP is that clever ? It actually changes the pixels per inch? What's happening there? It must be throwing pixels away on some edits, creating new pixels on others?
Meanwhile I had a thought in the night...
Isn't the crux of my problem my insistence upon getting the mix of photos onto one printout?
Together with letting GIMP decide the pixel size of the printout canvas?
GIMP has decided 180 ppi I suppose because that's the default on my setup when I ask for a new canvas.
Each photo actually has a different ppi because though all taken with the same camera at the same resolution my cutting a part out to use for the passport means I am making a different ppi for each one based on the number of pixels I've had to cut out from that photo - requiring each cutout to shoehorn into 48mm x 33mm. Is that right?
So that 737 x 1072 actually is meant to be a 33x48mm pic with a dots per mm of 22.3 which at 25mm per inch would be something like 558dpi.
So I, for that pic, should tell GIMP I want a new canvas measuring (4 x 558) x (6 x 558) in inches. And so on...
I think I've got that right have I? Learned something there?
I will try that and as I say I will try your suggestions and really learn something, hopefully.
One needs understanding isn't it? Not just blindly doing things. My current understanding is so miniscule. I don't know the difference between a mask and a layer. I don't know what to do, if anything, about 'floating layers', don't know about these alpha channels and whatnot.... don't know nuffin....
later: ah. not so difficult. both of you are simply talking about scaling. and it seems to be the answer. thanks. that way I don't need to make different printouts for each.
GIMP is that clever ? It actually changes the pixels per inch? What's happening there? It must be throwing pixels away on some edits, creating new pixels on others?