We present a photometrically accurate restoration of the K- and F-coronae from white-light images obtained over 24 years [1996 – 2019] by the Large-Angle Spectrometric COronagraph (LASCO-C2) onboard the Solar and Heliospheric Observatory (SOHO). The procedure starts with the data set of unpolarized images of 512 × 512 pixels produced by the polarimetric analysis of the routine C2 polarization sequences (Lamy et al., Solar Phys. 295, 89, 2020) in which the F-corona, the instrumental stray light, and possible remnants of the K-corona due to the imperfect polarimetric separation are entangled. Disentangling these components requires a complex procedure organized in three stages, each composed of several steps. Stage 1 establishes the distinct variations of the radiance of these components with the Sun–SOHO distance, and generate a new data set of median images calculated for each Carrington rotation. Stage 2 achieves the restoration of a set of 36 stray-light images that account for the temporal variation of the stray-light pattern, in particular those associated with the periodic roll maneuvers of SOHO, which started in 2003. Stage 3 achieves the restoration of the F-corona, and a time series of daily images is generated. Combining these images with the set of stray-light images allowed us to process the whole set of routine LASCO-C2 images of 1024 × 1024 pixels (approximately 626,000 images) and to produce calibrated, high-resolution images of the K-corona. The two sets of images of the K-corona, that produced by polarimetric separation of 512 × 512 pixels images and that presently produced by subtraction, are in excellent photometric agreement. We extend our past conclusions that the temporal variation of the integrated radiance of the K-corona tracks the solar activity over Solar Cycles 23 and 24, and that it is highly correlated with the temporal variation of the total magnetic field. The behaviors of the integrated radiance during the last few years of the declining phases of Solar Cycles 23 and 24 are remarkably similar, reaching the same base level and leading to a duration of 11.0 years for the latter cycle, in agreement with that derived from sunspots.

我们通过太阳和日球天文台（SOHO）上的大角度光谱日冕仪（LASCO-C2）在24年[1996 – 2019]中获得的白光图像中，对K和F冕进行了光度学上的精确还原。该程序从通过常规C2极化序列的极化分析产生的512×512像素的非极化图像数据集开始（Lamy等，Solar Phys。295，89，2020），其中纠缠了F电晕，仪器杂散光以及由于不完善的偏振分离而导致的K电晕的残留物。解开这些组件需要一个复杂的过程，该过程分为三个阶段，每个阶段由几个步骤组成。第1阶段确定这些组件的辐射度随Sun-SOHO距离的明显变化，并生成为每次Carrington旋转计算的中值图像的新数据集。阶段2实现了一组36个杂散光图像的恢复，这些图像说明了杂散光模式的时间变化，特别是与自2003年开始的SOHO的周期性滚动操作相关的图像。阶段3实现了杂散光模式的时间变化。 F日冕，并生成每日图像的时间序列。将这些图像与一组杂散光图像结合在一起，使我们能够处理整个1024×1024像素的常规LASCO-C2图像集（约626,000幅图像），并产生经过校准的高分辨率K光晕图像。通过极化分离512×512像素图像生成的K-电晕的两组图像，以及目前通过减法生成的两组图像，具有极好的光度一致性。我们扩展了过去的结论，即K日冕的整体辐射的时间变化跟踪了太阳周期23和24上的太阳活动，并且它与总磁场的时间变化高度相关。在太阳周期23和24下降阶段的最后几年中，综合辐射的行为非常相似，