I am a visitor..
I am going to Netflix, Uber or Airbnb, for example..
I specifically chose to go there..
They are "brands" I know what to expect, chances are I chose to go there, I may have even typed them directly into the address bar, minimum I know their name(s) when I see it ( them ) in SERP, and I click on it..
Am I going to " bail" ( go elsewhere ) because the page takes 3 seconds ( maybe more , maybe less ) extra to load due to a background image ?
Probably not..I know where I'm going..

You are website "x"..I have not heard of you, you have no "brand" ( I'm presuming much there ) maybe.. ..

Will I wait 3 seconds ( maybe more, maybe less ) extra ,for your page with background image to load ..

Maybe..
Do you feel lucky ?

If you make your background image really small ( data size ) and load it real fast..

Maybe you'll get lucky..

..

de rien :)

ps..If you are going to try it..may as well make the background image into a slide show..if your pages already depend on js..or if most of your visitors use browsers that can use CSS3 you can switch images with just CSS..for those who are not allowing js..

You can do other stuff with either method..whether or not it will "hook" your visitors depends on their "demographic" ..
Best way to know ( if you don't already) ..test ..a / b..

HTH :)

Yes good point. What is true for a great brand is not necessarily true for a lesser known website. But even for big companies, I am not convinced that the giant photos in the background are a good solution.

However, I note that the websites of Netflix, Uber and Airbnb are slow indeed ... but not extremely slow: the loading time is from 2 seconds to 2.6 seconds. I do not think this slow loading is sufficient to deter a user.

Thank you very much for your advice.:)
Merci de m'éclairer! :)

But obviously this slower loading speed might be sufficient for a web page (from a small or medium website) to have a lower rank in the SERPs.

It ( load speed) is also going to depend upon where you are hosting, and where your traffic is coming from ..
If France is where your visitors are coming from, better to host in France..load times will be shorter..
Btw..I just tried netflix, airbnb and uber..( I'm In Brittany )..current speed down on the DSLAM to my install is "upto 98 megs"..
ATM I have 40 megs down ( just tested )..netflix, airbnb and uber load lightning fast, but they will be using CDNs..
Tested Netflix again..
Their background images are both around 100kB..their html is around 100 kB..their complete page ( with scripts and CCS is around 1 meg ) so the images are not hurting them any..particularly when you note the images are each around 2000px by 1125 px..
Their k.js file is the biggest in there at 582kB ..ouch !

I'd say you generally want to stick to a solid background color unless the color is very faint and transparent looking..

Thanks for your replies Leosghost and WhatJUT.

Yes that is my opinion too. But I wondered if I was wrong, since many big websites do not do this.

I have to agree with Leo, I suppose it works well with big name companies. When we tested this with one of our clients, the bounce rate went through the roof.

Something I've seen some sites use is incrementally increase the resolution of the image. This way the page will load quicker. Alternatively, the large image download can be left for the end, so that the rest of the page can be rendered. This will make it seem like it's loading faster.

Interesting! :)
Thank you Domainchef.

Large background images are nothing more than wall paper. I look at the number of computers in the world ... how many users actually put wall paper on their systems? Not that many. I suspect most are interested in USE and content rather than pretty pictures. That said, if a client wants it, I install it with the most highly optimized image possible to provide the result desired.

1) Yes.

2) The customer is always right. ;)

Thanks for your insight Tangor. :)

I could add that most background images on websites are the result of graphics designers working overtime to hang on to a job, but I won't. :)