Deep-IR images of selected regions in Perseus

Description: Deep near-IR images (J,H,Ks) taken to produce high-resolution extinction maps. Regions neer dense clouds show some extended emission (cloudshine) which we believe to be Galactic starlight scattering off dust. One region, L1448, shows a number of remarkable outflows. Comments on Reduction: Cloudshine complicates data reduction. Regions covered by extended emission will be dimmer than in reality, since sky-subtraction will subtract out real signal. This process acts like a sharpening filter, enhancing contrast in these images. Telescope: Calar Alto 3.5-meter Status: Complete Sampling: Seeing during these observations was good, often 0.6-0.7 arcseconds. Areal Coverage: Each frame is 15.4 by 15.4 arcminutes. A total of seven science frames and two control fields were obtained.数据集说明：为生成高分辨率消光图（extinction maps）而采集的深场近红外（near-IR）图像，波段覆盖J、H、Ks。密集云团附近区域呈现出一定的延展辐射（云辉，cloudshine），我们认为该辐射源于银河星光经尘埃散射。其中L1448区域存在多处显著的外流结构。 数据处理说明：云辉会增加数据处理的复杂度。延展辐射覆盖区域的观测亮度将低于实际值，因为天背景减除（sky-subtraction）过程会扣除部分真实信号；该过程类似锐化滤镜，可提升图像对比度。 望远镜：卡拉阿托（Calar Alto）3.5米口径望远镜。 观测状态：已完成。 采样参数：本次观测的视宁度（seeing）良好，通常介于0.6~0.7角秒（arcseconds）之间。 区域覆盖范围：单帧视场为15.4×15.4角分（arcminutes），共采集到7幅科学帧图像与2幅视场对照场。