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We present ground-based optical (BVRI) and infrared (JHK) photometry for 15 galaxy fields previously observed with HST as part of the Medium-Deep Survey. We use the HST images to determine bulge and disk scale-lengths at 0.1--0.2'' FWHM for 70 galaxies in the V and I-bands. We constrain their star-formation history from their ground-based+HST BVRIJHK colors. For galaxies too faint for MMT spectroscopy, we use their BVRIJHK photometry to constrain their redshift-range through Bruzual's (1990) spectral evolution models. Comparing these photometric redshift estimates to spectroscopic redshifts for a brighter subsample, we find acceptable agreement.We conclude this is an efficient way of finding large numbers of field galaxies with z$\geq$0.8. Using photometric redshift estimates, we extend the $\Theta$-z relation for HST bulges and disks (using world models with q$_o$=0.0---1.0, see Mutz et al. 1994, ApJL, 434, L055) to z$\geq$0.8 (V$\geq$ 24 mag), beyond most ground-based spectroscopy.
We also observed three brighter (17.5 $\leq$ I $\leq$ 19.0) galaxies with spectroscopic redshifts of z=0.12--0.28 in the K-band with the Steward 90 inch FASTTRAC tip/tilt corrector system. Under seeing conditions of 1.75'' FWHM for a single image of 1.0 second, we derived K-band imaging with FWHM = 1.076'' for a stack of 158\ \ 60-second images. We present their V, I, and K-band light profiles, and V--I and I--K color gradients. The V--I and V--K color profiles show that the object at z=0.12 is likely an early-type galaxy with an exponentially declining star formation parameter $\mu$=0.4. The object at z=0.23 is an early-type galaxy with $\mu$=0.7. The object at z=0.28 is a late-type disk galaxy seen nearly edge-on. We discuss using FASTTRAC under better seeing conditions and at telesopes with a more optimal ratio of Fried-parameter to mirror-diameter. This work was supported by NASA/HST grants GO-2684-0*-93A from STScI, which is operated by AURA, Inc., under NASA contract NAS5-26555.
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