Lukabulla

Hi , I was recently sent some old family photos jpegs .
72 dpi and postcard size on screen .

I've been trying to enlarge with PS .. tried changing the 72 dpi to 150
but the image is pixelated and distorted , tried keeping the 72 dpi but
changed ' image size ' to larger but again the same bad result ..

But on one image I right clicked and saved as Desktop screen background
and it was blown up to my 27 inch monitor screen without distortion.

How does this work ? and how can I blow up an image to same size using PS ..

Cheers

In-lightened Loc: Kansas City

Topaz has a program....gigapixel that works really well. You could try do a trial and see what you think. We have 6 boxes of old family images...it will keep hubby busy foreverhttps://topazlabs.com/gigapixel-ai/

DaveMM Loc: Port Elizabeth, South Africa

Have you tried just doubling the pixel count from 72 to 144 dpi, instead of 150. No interpolation will be needed from the program so perhaps there will be less objectionable pixelation.

I haven't tried this, but it seems logical. However, you cannot put back what is not there so your results will always lack something.

Joexx

You need to find that "enhance" software they have on those tv crime shows :-)

JohnSwanda Loc: San Francisco

Does whoever sent them to you have higher res versions of the photos? Or are the original photos available for scanning at higher resolution?

gvarner Loc: Central Oregon Coast

First, resolution for a file is in ppi, not dpi. Second, to find the equivalent physical dimensions of the file, divide it’s pixel dimensions by the resolution of 72ppi. For example, a file that is 720x720 pixels per side would be about 10x10 inches square if it was printed at 100%. If you print it bigger than that, you would start degrading the result. The same would happen on a monitor if the file was zoomed up to greater then 100%,,it would start to pixelate. At least that’s the way I understand it.

FreddB Loc: PA - Delaware County

That's kid stuff
I had a friend - worked for the "government" - sent a picture of me standing on the flight deck of my ship in the Tonkin Gulf back in the day. Taken from a sattelite camera, it was clearer than my yearbook picture! Funny, but I haven't heard from him in years. And I haven't been able to find the photo since the last time we moved. Odd how things disappear, isn't it?
Have to go now, someone's at the do

Rongnongno Loc: FL

You know of any printer that still prints a 72DPI??? How old is it? Can you still find supplies for it?

Rongnongno Loc: FL

err, think again. Each pixel is magnified 4 times, not two to start with. 72~155 increase is 215%. The difference is not significant visually even if in math it is.

There are tutorials on the web that explain how to with mixed results.
One thing in common: Do not go up scale too fast. 200% is waaaaaaaaaaaayyyyyyyyyyy to fast.

Lukabulla

Thanks for all the Replies , but up to now ,
no one has answered the question .. How come it
enlarged a great many time when I right clicked
save as Screen background with out distortion .

Rongnongno Loc: FL

I would not worry about the PPI reported but about the overall size of the files (dimensions in pixels). Your printer DPI will determine the size of the print (size/DPI). This is the same for your monitor that has a fixed 'DPI'. It uses the image dimensions, not the reported PPI

Lukabulla

by the way I have no intention of Printing the image.
I just was a decent enlargement on file .

Rongnongno Loc: FL

Post a sample and use 'add attachement'.

CHG_CANON Loc: the Windy City

Resolution refers to pixel resolution. And pixel resolution is expressed by the length x width of an image as measured in pixels. Example: 6000px X 4000px = 24 megapixels (or 24MP).

Note there is no reference / relevance of 'dots' in the expression of pixel resolution. There are no 'dots' in pixel based technology and you should simply ignore this outdated value that only will lead to confusion as you try to resize your images to increase the pixel resolution.

Consult your display manual and determine the pixel resolution of your screen. Is it at or around 1920x1080-pixels? If you want to fill your screen (whether laptop, desktop or high-def TV), all you need is a file that matches (or nearly) matches to the pixel resolution of the target display. Note there are no 'dots' in the pixel resolution of a display device.

Any digital editor worth bothering with can increase (or reduce) the pixel resolution of an existing image. You mention using PS. That 'resize' option is easy to use in PhotoShop. Just express the target size (in Length and Width measured in pixels) and create the target file.

More details, including examples of popular software, are provided at: Recommended resizing parameters for digital images

gvarner Loc: Central Oregon Coast

I agree, it shows how little I understand about the relationships - pixels, inches, resolution, monitor image, printer image. This old brain can hardly keep up. And then they throw PPI and DPI at me. All I really know is how to get an image zoomed up on my screen and what it looks like when I try to print it too big. All the rest is buried in the weeds somewhere.