A complete dataset of sunspot drawings recorded at Sacramento Peak Observatory (SPO) from late 1947 till mid-2004 has been digitized. We present the history of the observations and describe the data included in the drawings. We compare the sunspot number index calculated from the SPO data and the International Sunspot Number (S N v2), and we find that both series exhibit a similar behavior. The ratio of two sunspot numbers is relatively constant at about 1.2 – 1.3 during 1955–1995, with larger variations present at the beginning of the time series. This work represents the first step for the publication of the SPO sunspot catalogue in digital format. More information, such as positions and areas of sunspots, will be included in the next versions in order to provide the space weather and climate community a more complete sunspot catalogue with good quality observations.

中文翻译：

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萨克拉门托峰国家太阳天文台的太阳黑子图集（1947-2004）

萨克拉门托峰天文台 (SPO) 从 1947 年末到 2004 年年中记录的太阳黑子图的完整数据集已被数字化。我们介绍了观察的历史并描述了图纸中包含的数据。我们比较了根据 SPO 数据计算的太阳黑子数指数和国际太阳黑子数 (SN v2)，我们发现这两个系列表现出相似的行为。1955-1995 年期间，两个太阳黑子数的比值相对恒定，约为 1.2-1.3，时间序列开始时的变化较大。这项工作代表了以数字格式出版 SPO 太阳黑子目录的第一步。更多信息，例如太阳黑子的位置和区域，