Versperus said:
My only complaint is that I can't figure out if there is a way to get uploaded resolutions from that site.

From what I could tell, this seems to be the direct image format on newTumbl:

https://dn0.newtumbl.com/img/<blog ID number>/<post number>/<digit possibly relating to an image's upload order in the post>/<unique image ID number>/nT_<a large amount of alphanumeric characters>_<number derived from "300 * n" [where "n" is any number from 0 to 3] for recompressed previews restricted by either width or height>.<filename extension>

I looked at a few random newTumbl blogs and viewed their images directly to determine this format. The images in this post and this post worked out the best for me in determining this.

By the way, the preview size URLs (just before the filename extension) seem to be _300, _600, and _1200.

• _600 appears to be the default used in posts and appears to restrict images to a maximum height of 800 pixels, not 600. — e.g. [1], [2]
• _1200 appears to restrict images to a maximum height of 1200 pixels. — e.g. [1], [2]
• _300 appears to restrict images to a maximum width of 300 pixels. — e.g. [1], [2]
• It also seems that to get the original uncompressed images, either the number has to be changed to _0 or just remove the underscore and number at the end altogether.
• _0 examples: [1], [2]
• no-underscore-or-number-at-the-end examples: [1], [2]

Both formats appear to deliver the exact same image. If the image is of a relatively low res to begin with, then newTumbl doesn't tack on any preview size number and just delivers the original image as is on the post, like this one.

Update: I should also note that non-animated images will always be loaded with .jpgat the end, even if they're actually a PNG image. Changing the direct URL of an original quality image on the site for a JPEG to .png or a PNG to .jpg will load the same exact image either way.

Update 2: Same format is used for MP4 videos on there, just ending with .mp4. — [Post with video], [direct video link]