sugar in boil kettle affecting pre-boil gravity?

[Otter]

I'm brewing a Belgian Tripel, and plan on adding 2.5 of table sugar into the boil kettle.

When I add it to the recipe, my pre-boil OG goes up. Is the recipe assuming that I've added this in already?

I usually use the pre-boil OG to determine what I should be getting out of my mash tun, but the sugar throws it off.

Anyone got any suggestions?

[slothrob]

You can uncheck the sugar for now, to calculate your preboil gravity.

Then you can post under Feature Requests and ask for a way to enter sugar to the middle of the boil so that it doesn't affect preboil gravity.

[jawbox]

doesn't it also only calculate the attenuation of sugar based on the yeast strain rather than 100%?

[slothrob]

I believe so.