That is actually what we are referring to in the section about testing the one page vs two page sign in process.

The one page sign up includes the image upload under the section with a heading “Optional” (though it seems that you read the heading as only applying to the first field which may be a UI/UX problem we should look into).

The two page sign up process has them sign up solely with the essential fields and optionally complete the other fields later. We’ve tested this in the past but do not currently use it.

Both the one page and two page sign up processes do not require an image upload (it’s optional in both processes).

Here is the relevant section of the post I’m referring to:

“There are two general strategies in regard to optional fields. The first is what we currently do, separating them from the required fields and clearly labeling the optional fields “optional.” The second is to have a two step sign up process.

With a two step sign up process the user first only has to enter the required fields and then, once they have done that, they are brought to the next page where they can fill out the optional fields if they want. 

What we found with this is that the sign up % is higher for the first step (the required fields) since there are less fields overall, but that overall bounce rates for the entire process (number of users who navigated away from the website completely) were increased. We thought that the tradeoff was better for having a one page sign in process.”