Logging a Potluck dinner

just log the closest thing you can to what you had. Say someone brought in peanut butter brownies, search peanut butter brownies and log that, you will not be able to get it exact but it sounds like you saved your calories for this anyway so a aproximation is as close as you can get without getting everyones recipies and breaking them down via ingredients.

I had this same problem a few days ago. I logged what foods I had brought, then did the best I could with the "bites" of others. Then just added quick calories.

One cup of cooked cous cous is 176 calories. One cup of cooked quinoa is 222. One cup of brown rice is 216. One cup of cooked barley is 193. If you guess wrong, you'll still be in the ballpark.
If you think oil was used during cooking, as with rice pilaf, add an oil value. Just get approximations and guesses in the log.
Don't spend a lot of time sweating the small stuff.
And give yourself credit for doing your best in a tempting situation.
The standard potluck guideline is to fill at least half your plate with veggies, and sample only one dessert.

The first time I had to log a potluck, I searched the database for "potluck" and found several entries. I used one of them since some other member had already gone to the trouble of tallying or estimating it. The search results range from "Generic Vegan Potluck" (500 cal. plate) to "Potluck Gone Bad" (2,000 calorie plate). This might save you some time.

What are "quick calories"?

It isn't the calories that are "quick" as this makes no sense at all. Rather, this refers to a feature in MFP where you quickly add a number of calories for a meal rather than log exactly what you ate. You can use this, for example if you eat in a cafe or resturant and they have a calorie figure for a particular menu choice but no other nutritional info. It is also useful for situations when the best you can do is guess. I use the Android app and it's at the bottom of each of the lists of things to add to each meal, i.e. "Frequent", "Recent", "My Foods", "Recepies".

If these events are very occasional I'd not worry too much about it. If they happen more frequently then I'd plan the rest of the meals around it for example my having a modest breakfast and a light luch, for example salad.

I do pretty much exactly what everyone is saying..after dieting for years you can pretty much calculate in your brain what a plate of "bad" food, or healthy choices might be and just guesstamate what it is..the rest of the day I eat really really light and then try to add in some exercise or a walk to help cover some of it..as long as it's not a frequent thing it will work out in the end. Just be honest with yourself and try to pick out the best options if there are any, otherwise eat smaller portions..you'll have to eat that way in order to keep the weight off in the future anyway.

The problem is...I don't know what half of it was? Was it Quinoa? Or was it Farro? You know?

When I'm making a guess like this (very rarely, if ever) I often pick the one with more calories. For me, that accomplishes two things: It helps to ensure that I do not go over...and it teaches me a lesson for being unprepared or for eating a food I can't identify...haha.

Good luck to you.