It seems the forum software automatically scales photo links. Some sites I upload photos to require you to manually resize the photo to, say, 900 pixels wide.
Since MR simply redirects the URL to another hosting site, THAT hosting site’s constraints are what matter.
Your picture looks great, and even better when I click on it. Another click, and it’s so big that I have to scroll, up and down and side-to-side, to inspect it all.
If you don’t mind telling us, where do you have the photo stored, so that it can be placed here with a simple copy and paste? (and get the successive enlargements, too?)
In days past when all was slow, it was rude to post a big picture that would take a long time to download.
So, you can reduce the size of your photo so that it will zip right in. You can even get a Windows add in so that you can do it right from your photo directory without opening a photo program to resize things manually.
And sometimes you just want a SMALL photo…
These are HO scale subway maps for use on my subway platforms.