Resizing or compressing file sizes

[Kayla Groening]

Hello.

This is my first month posting a picture for the monthly art contest and I just read (after posting my entry) that the file size should be a max. of 500 mb.

I think mine is just shy of 2500 mb.

I need to lower the file size but am wondering which method is better: resizing the image or compressing it? Any thoughts and/or advice would be greatly appreciated. I'm thinking that compressing would be better but I'm worried of losing image quality.

I work with traditional mediums, but usually scan my art and do final touch ups with GIMP or INKscape.

[NessIllustration]

@kadelex Is this right? Max 500 mb? Yours is 2500 mb? This doesn't sound right.. When I export my files as a full size PNG with no compression, they're usually around 5 mb and rarely more than 20 mb. Even my original PSD files, layered, are rarely more than 100 mb! How big is the size of your canvas? If you're scanning and the file size is this big, your settings are probably not optimal. You should be scanning at 300-600 dpi, any more is not helpful.

But back to your original question, I always suggest reducing the size first, see if you can get it under the file size requirement this way without making it too small, and then only if it's still too large play with the compression. Resizing makes the image smaller without affecting image quality, whereas compression keeps the image just as gigantic but reduces quality. For the purposes of the contest I would think you don't need more than 2000 px wide for your image. Try resizing it to that size and see if it goes under the requirement. For your image to be 2500 mb the size of it must be gigantic!

[Amanda Jean]

Check your image resolution. It's possible that you scanned it at 150dpi or higher. Images for screens only needs to be 72dpi. You should be able to change this in your document settings.

Make sure when you save your images, they are *.jpg or *.png, and use the compression settings at large or highest quality. It should definitely not be 2500mb unless you are sending something to print, even then that's a bit ridiculous. Save it as a separate document.

Generally I upload files to this forum no bigger than 1000px in width (usually 800 if I can help it).
And a tip, if uploading for instagram, it doesn't need to be any larger than 1200x1200 pixels.

[DOTTYP]

@kadelex Are you scanning a traditional art piece,because when I scan A3 at 300dpi is usually around 27MB. I then I put in into Photoshop and resize it. If you change the resolution to 72dpi or even 144dpi it will automatically reduce the Mb size to something more manageable. I dont use Gimp or inkscape but most of the software is similar.

[Kayla Groening]

Oh dear. I just checked my numbers. I must have been way too overtired when I posted this question (I blame the baby...no wait the baby sleeps all day...the toddler on the other hand )

I was mixing up my mbs and kbs.

As per the monthly contest rules (link text the file size should be no more than 500 kb.

When I scan at 300 dpi, my image comes to around 3.5 mb (3500 kb); so I will still need to reduce the file size.

@NessIllustration , thanks. I'll try to re-size the image and see if I can get it a decent size.

Sorry for the confusion.

[NessIllustration]

@kadelex Oh that makes more sense! Alright so 500 kb is small for an image, meaning they want small and light files for fast internet viewing. I suggest to keep scanning in 300 dpi just to have a large version handy in case you need it later, then resize a smaller copy for the contest. 72 dpi is the standard for internet only images, and if you get the image between 1000-2000 pixels wide you should be good If it's still too big, try exporting in JPG and compressing the quality a little bit. I've noticed no significant quality loss when compressing between 75-100% quality.