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Extensive results from the commissioning phase of PUEO, the adaptive optics instrument adaptor for the Canada‐France‐Hawaii Telescope (CFHT), are presented and discussed. Analyses of more than 750 images recorded with a CCD and a near‐IR camera on 16 nights in wavelengths from B to H are used to derive the properties of the compensated wavefront and images in a variety of conditions. The performance characteristics of the system are analyzed and presented in several ways, in terms of delivered Strehl ratios, full width half‐maxima (FWHM), and quantities describing the improvements of both. A qualitative description is given of how the properties of the corrected images result from the structure function of the compensated phase. Under median seeing conditions, PUEO delivers essentially diffraction‐limited images at H and K and images with FWHM ∼ 0 \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepac...

H and J band observations of 3C273 from the commissioning run of Altair are presented. The data are compared with HST data, and some new morphological results on the host galaxy are discussed.

Current astronomical adaptive optics (AO) systems are not able to fully correct the atmospheric turbulence. As a result, the quality of the AO long exposure images is degraded by a residual blur which significantly reduces the contrast of the fine details [1]. Removing this residual blur is the field of image restoration (deconvolution) and since this problem is general to many imaging applications, many different methods have already been developed. To achieve an accurate restoration however, an accurate estimation of the system Point Spread Function (PSF) is usually required. For adaptive optics imaging, the shape of the PSF depends on how well the deformable mirror is able to compensate for the wavefront distortions. This “degree of correction” in turn depends on the size and magnitude of the object used as a reference for wavefront sensing, but also on the characteristics of the turbulence, which is known to be a non-stationary process. As a results, the AO PSF is highly variable [2]. The usual way around this problem involves dedicating of significant portion of the observing time to the sole acquisition of a point source, from which the current PSF is estimated.