Rule of thumb that I often see is: width of chandelier should be equal in inches to the length plus width of room (in feet). Height of chandelier should be 3 inches for every foot of room's height. In your case that would give you a 14 inch wide and 57 inches tall. I doubt you'll find much with dimensions close to that. LOL! I'd probably go quite a bit wider than 14 inches especially since the foyer is open to the great room. Maybe up to 22 inches wide. But you need something to fill up some of that well-like space and give it some definition so definitely look for something that is taller than it is wide. I'd want at least 42 to 44 inches tall and I'd want to be able to hang it so that it is either centered in the foyer window or so that the bottom edge of the chandy is at the same level as the bottom edge of the foyer window. LightingUniverse.com lets you search on both width and height at the same time. It isn't a perfect search because height is sometimes measured from the ceiling to the bottom of the fixture and therefore includes the length of any fixed rod - or even sometimes the length of the chain! - rather than just giving you the dimensions of the "decorative part" of the fixture which is really what you want to focus on. But at least you can eliminate fixtures that are much too wide for your space and narrow down the search for some with a body height which is great enough for your space.

OMG, Chispa! That is awesome! I am currently living that problem, lol. We have a 20’ ceiling in our foyer and I have to do the hook thing from the upstairs hall, and I have the window washer people clean it twice a year when they come. I just dust it with this one of those huge extension duster from Sharper Image in between. I would LOVE to just lower it! I wonder if I can install it retroactively? Agree, you need a chandy with HEIGHT more than width.

The other thing to consider when choosing a size is the height that it will be hung at. Is there an exterior window that you want it to be centered in? Is there a stair in this space, or an overlook? If we were talking traditional candelabra chandeliers, I would start with the three tier version in most lines. For other styles I would look at fixtures with similar dimensions to these.

Ok, so the door is 8 and the ceiling is 10, you have only 1.5 feet to "hang anything so it not literally just missing the door. Personally, I would not hang anything i would opt for a flush mound about 12inches deep On the interior again, the door swings in at 8 feet the 7 foot i would go no larger than 12:: https://www.houzz.com/discussions/4769993/door-height-with-10-ceilings scroll about half way down to see her entry fixture these are probably 12-14 inch globes