New Donor Report vs Gift/Detail Summary Report

Hi! I am running reports on New Donors by year. I initially ran a New Donor report using a constituent query that was to only look at Individuals with a First Gift Date range. I plugged that query into the report again with the date range and then the campaigns, gift types I needed to look at. My development manager did not feel confident in those numbers so I suggested to try a Gift/Detail report. I ran the same constituent query with the same filters and date ranges and the New Donor report came up with about 60 more donors and $7,550.00 more total gifts. I would normally use a Gift query with the Gift/Detail report but it seems that there is no way to filter out the First Gift dates as you can in a Constituent query. Hope someone can help me sort this all out! Thanks!