size of background image

[swedeheart]

I'm helping a friend with her Blogger blog. She wants to use one of her own photos as a background image, which is fairly easily accomplished using Blogger's Template Designer, you just upload the picture, nothing to it.

My thing is, I want to keep the picture as small as possible - pixel-wise as well as kb-wise - to keep the page from loading slowly. But at the same time I don't want to reduce the size too much as this would mean that some users with big screens would see "beyond" the picture (=see the monocolour background that they're not supposed to see).

The kb issue is a non-issue as Blogger's allowed maximum for a background image is 300 kb anyway, so I don't have to think too much about that aspect. But pixel-wise I'm confused. Blogger themselves say:

"If you want a full-screen background, we recommend using an image that's 1800 pixels wide and 1600 pixels high, so that the background image can fill the entire screen even for the readers with large monitors."

A width of 1800 or even 1900 makes sense to me. But a height of 1600 pixels?? Is that really necessary? It's possible I have the answer myself but I'm not sure: When you upload your personal background image to the Template Designer, you have the choice of ticking a box that says Scroll with page. In other words, as you scroll downwards, you also move from head to toes of the photo. I can understand the need for a 1600px height if you tick that box, but if you don't? If you want the background image to be still, while the text moves? Would you still need 1600px?

I do really want to prevent ANYONE "seeing beyond the image" so don't want to compromise and "risk it". But nor do I want the image to be as high as 1600px unless it really is necessary.

[Mosaic]

If you have the option to 'scroll with page', then I suppose the normal proportions of a photo would be OK. Why not try it ans see what happens? you can always change it if it's not working as you want it to.

[swedeheart]

Mosaic she wants the background image to "stand still". Not a problem - just don't tick that box. My question is: Does the height STILL have to be 1600px?

Whether or not it will be working as I want it to is not all that easy to know, as I only have one computer and it may look very different on others. Now, I know there are sites where you can check what a page looks like with this resolution and that resolution and this monitor size and that monitor size... but it's very time-consuming and I thought somebody here might simply know the answer.

[Mosaic]

No, try it at the 'normal' proportions you'd get if you sized the image to 1900 px wide.

[swedeheart]

Thank you for wanting to help, Mosaic, but I do feel as if I'm not able to get the point of my question across. No great wonder, since British isn't my lingo and I'm not of a techie disposition:)