What I used to do when I was working with photoshop. I opened the image, resized the image to 600px on the long end. Made the resolution 72ppi and then uploaded. I just did a bunch of screen shots and was going to post to illustrate my process, but they were all too big. I haven't done it like this for a long time, but I can see that it has changed quite a big since the last time.

I personally just upload from my website using the BCC code and just paste it into the body of the post I am writing. Works super easy.

I used to use picassa for posting since I kept a blog and had the photos readily available. When I did that, it clicked on the insert image icon in the task bar of the post. Used post from URL and pasted the image URL from picassa. It was pretty easy to do also. In picassa if you don't want someone to see your photos, you can set it to anyone that has a link or only you. You must use the anyone with a link if you want it to show on here. It won't allow someone to click on the photo and get to that album, but rather just displays the image here.

If you plan on posting images to more than one of the forums you read, I would suggest either going to flickr route or get a picassa album. They are really easy to use and share your stuff.

I believe the reason the sizes keep shrinking for uploads here are due to the storage they maintain for the forum. There are more members now than when the site first started the forum and I don't think they want to upgrade the storage for individual pictures since most use flickr, picassa, their website, or some other form of adding photos.

Sorry I wasn't more help. I tried....