How do you upload non iphone (DSLR) images to Instagram?

It is a very basic question.... How do you upload non iphone (DSLR) images to Instagram? It looks like I can only upload images I have taken with my phone....Is that ture?
I would like to upload my wedding photography work onto Instagram.
Please help!

i was using Dropbox to do it, upload to dropbox from your computer, then "add" to instagram from Dropbox on your phone. However, now I am using Hootsuite to do it. I can upload to Hootsuite from my computer and schedule images (up to 5 per day) for the future. Then the Hootsuite app on my phone notifies me to upload to Instagram. So it's not an auto upload but its pretty simple. Allows you to write all of the # and descriptions on your computer as well instead of having to do it from your phone which is something I really appreciate, I hate writing on my phone haha

There's a couple of options.

First of all, there's the windows application called 'Gramblr' which really worked well for me.

I have however left it in favor of running Instagram in a virtual machine, there are various software companies who offer (Free) software to do that with.

My favorite is Genymotion, but you do have to install google play manually and that requires installing some zip files from the internet, including x86 interpretation pack and such. So better if you are slightly geeky/inquisitive