How to keep image quality for my instagram picture?

[Gregory Dubus]

Hi,

After opening a new document in 1080*1080 (Instagram size) in 400 DPI, I added a picture which is 50MG jpeg. Then, when I save it, the file is only less than 2KB which is not good as the image lost a lot in quality (I can see the lines not been straight anymore). As I would like to divide this page in 4 or 6 to send a few posts to get slowly my full image revealed on Instagram, I need to be able to keep an excellent quality of the image.

So, is somebody knows how could I keep a very good quality of my image when putting it in a 1080*1080 page? (So, image having a few MG instead of a few KB)?

Thanks in advance for your support,

Greg.

 

[John Rostron]

How big was your 50MB jpeg file? I would guess it is more than 1080x1080px. If you resize (Document > Resize) this to 1080 by 1080px, and tick the Resample box, you have the option of various resizing algorithms. For good quality choose one of the Lanczos options (try non-separable first).  When you export to Jpeg (File > Export), you can adjust the Jpeg quality slider and check the file size at the bottom of the dialogue. Note that it may take a moment or two to calculate the size. Note also that there is a compromise between quality and size!

John

[markw]

I would also note that dpi is only relevant when printing, (and even then is often misunderstood!)
A 1080 x 1080 image @ 400dpi has the same pixel count as 1080 x 1080 image @72dpi.
It’s the number of pixels that matter and Instagram will only let you have a total of 1,166,400px! in a square photo post.
They let you have slightly more pixels in a 1080 x 1350 image but still that’s only 1,458,000px