In this short review we briefly discuss all the extensive low dispersion objective-prism spectral surveys carried out in the last fifty years for the study of the surface and space distributions of late-type giant stars, namely C stars. In the light of data obtained and new discoveries, the expediency of undertaking a deep mI low dispersion spectral survey in the near-infrared spectral region is considered.

In order to check the utilisation of 4-degree objective prism spectra for the deep spectroscopic galactic structure study, Rose’s (1984) seven indices between 3500 Å and 4400 Å for 19 Hyades stars were measured on a Kiso Schmidt prism plate, L3496. By comparison with those of Rose (1984), it is found that his spectral indices, Hδ/FeI, Hγ/P(4325), and P(3912)/P(CN) measured on these low dispersion spectra, are still usable. This result gives good prospects for a deep spectroscopic galactic structure program with the 4-degree objective prism and narrow band interference filters.

We have begun a deep objective prism Hα survey of starforming regions using the CIDA 1 m Schmidt Camera. We report here on the performance of the telescope for this kind of work, based on the study of selected areas in the Taurus-Auriga molecular clouds and the Ophiucus molecular clouds. Up to now seven plates taken in Taurus-Auriga have been visually scanned in a search for pre-main sequence candidates, with a coverage of about 120 square degrees over the whole complex, plus one plate taken in Ophiucus covering the entire cloud (≈ 18 square degrees).

We are conducting a long-term deep spectral survey to investigate the distribution of Ap and Am stars in selected fields of the Milky Way and in open star clusters of different ages. The spectral survey is based on objective prism spectra obtained with an eight degree prism attached to the 70/98 cm meniscus telescope (f/3, 135 Å mm−1 at Hδ) at the Abastumani Observatory. Kodak IIIa-J emulsions hypersensitized by baking in nitrogen gas are used in combination with a 500 Å FWHM filter centered on Hδ. A limiting magnitude of mB = 14 was reached in an exposure time of 120 m. Study of the objective prism plates is still in a very early stage. Observations of the central part of the same field taken with a CCD resulted in a limiting magnitude mB = 16. On the basis of spectral material obtained, a wide range of spectra may be classified in the MK system.

The distribution of emission line stars in Orion is presented, based on our recent surveys and other previous ones. Particular attention is given for the central 10 × 10 square degrees to compare some properties of emission line stars and OB association stars. As a result, a possibility of bimodal star formation is suggested in this region.

One of the programs conducted with the Bosscha Schmidt telescope is the study of loose star groupings and extended galactic clusters in the southern hemisphere (The 1963; Hidayat & Wiramihardja 1978; Hidayat et al. 1994). The aims of the study are, in short, to:

1. 1. investigate or to confirm the physical reality of the loose groupings.

2. 2. study the relationship between extended clusters or loose groupings with their environment.

3. 3. derive their physical parameters which ultimately can be used to construct the luminosity functions of the objects.

The purpose of the present paper is to present one of our results for the extended cluster OCL 1104-584 (NGC 3532). The results of studies of loosegrouping objects taken from the list of Loden (1979) will be presented elsewhere.

A brief review of observational studies of Trapezia-type stellar systems is presented. The important role of such systems in investigating problems of star formation is discussed.

We report the result of our survey observations in the outer part of the Orion star-forming region which consists of six Kiso sky areas (150 square degrees). In total, we detected only 48 emission line stars. The low surface density suggests that the Orion star-forming region probably terminates around these areas.

Near-infrared photometry is reported for 76 emission-line stars in outer regions of the Orion molecular cloud complex. Most of our program stars are selected from the Hα emission-line star catalog of the large-scale Kiso Schmidt survey of the Orion region. We confirm that most of the emission-line stars with strong emission detected in the Kiso survey are typical T Tauri stars with masses in the range 0.5 to 2 M⊙. Low mass stars have therefore continued to form in the outer parts of the Orion region, away from present day massive molecular clouds, until at least as recently as a few million year ago.

We have analyzed time-series data for 160 stars in the old open cluster M67. Approximately 400 CCD frames from two nights on the Burrell Schmidt have been reduced differentially relative to an ensemble of seventeen stable stars. We present data on two new variables and evidence of four new suspected variable stars in M67.

To investigate the spatial distribution of various stellar groups in the Hertzsprung-Russell diagram, it is necessary to have homogeneous observational data of MK spectral classification and photometry. This enables us to perform some statistical analyses with sufficient accuracy.

This paper reports BV photographic photometry of about 700 stars complete to mV = 12, in the direction of galactic anticenter with (l,b) = (169°, −12.4°), (178°, −2.4°), (184°, 8.9°). For the MK spectral data we used the catalogue by Bartaya and Kharadze (1992), which contains spectral and luminosity classes of 6042 stars in Kapteyn Areas Nos. 44–67. The observational data for this catalogue were obtained using the Abastumani Astrophysical Observatory 70 cm meniscus telescope and an 8°objective prism with dispersion 166 Åmm−1 near Hγ. The errors in classification are equal to ± 0.6 spectral subclasses and ± 0.5 luminosity classes, with a limiting magnitude of mV = 12.5.

According to McCarthy (1984) the objects detected in objective prism surveys for Hα emission line are a ”most unnatural“ group. Of course they consist of many natural groupings whose identities or other peculiarities could become apparent after observing them with higher dispersion and resolution spectroscopy. In some cases, however, their galactic locations and associations with other known populations, can provide a clue to their population types.

The aims of the objective prism surveys using the Bosscha Schmidt telescope can be broadly categorised as follows:

1. 1. Searches for galactic planetary nebulae in the region 240° < l < 360 °; |b| ≤ 10°, initiated by The (1968).

2. 2. Searches for T-Tauri stars in some southern dark clouds (Shinohara, Ogura & Hidayat 1989).

3. 3. Searches for variations in Hα intensities and luminous emission stars in some selected galactic regions, such as in the Puppis and Carina regions.

The combination of the wide field of Schmidt telescope photographic plates with fast measuring machines such as COSMOS and APM, had a major impact on the study of the global properties of the Magellanic Clouds. Results (based on UKST data) regarding the stellar populations and dynamics of the Small Magellanic Cloud are described here in some detail. The stellar content and kinematics of the intercloud region are also outlined, with particular emphasis on the importance of this region in understanding the interaction between the Magellanic Clouds.

Large complexes of young objects are common features in galaxies and are called superassociations, complexes and supercomplexes according to their size. They contain HII regions, early-type stars, associations and young clusters. Such large structures are expected to trace the star formation regions within galaxies. Star counts and spectral classification over extended areas, using direct and objective prism Schmidt telescope plates are good methods of determining the boundaries of these complexes and supercomplexes where the spatial density of early-type stars is enhanced. A project of tracing the supercomplexes in the Magellanic Clouds has started using plates taken with the UK 1.2 m Schmidt Telescope.

By contrast-enhancing and colour-excess analyses of BV RI CCD images of the central 12’.5 × 12’.5 region of M31 taken with the Kiso 105 cm Schmidt telescope, we found a “face-on” spiral feature of dark clouds, which are associated with Hα spirals. The feature can be understood as being due to accretion of gas clouds from companion galaxies and/or from a merger galaxy in the past 108–9 years.

This paper describes the results of searches for planetary nebulae on seven objective prism plates which were taken with the UK 1.2m Schmidt Telescope and cover the entire Small Magellanic Cloud. A total of 62 objects were detected; their spatial distribution is discussed.

In spite of the lower S/N and smaller dynamic range of photographic plates compared to those of CCD data, Schmidt plates still have the advantage of a large field of view, which allows us to study the structure of nearby large galaxies and clusters of galaxies. Investigating the internal and external errors of our surface photometry, we show that a careful analysis of photographic plates results in reliable surface photometry data comparable to CCD data for galaxies brighter than ∼ 17 mag. Recent studies based on photographic surface photometry catalogues obtained from Kiso Schmidt plates are reviewed and it can be shown that surface photometry of galaxies on Schmidt plates is still useful for understanding the local universe.

We report on a new survey for low surface brightness galaxies using Kodak Tech Pan 4415 film on the UKST, and demonstrate the advantages of this film over conventional IIIa plates when searching for faint, extended objects. Recent experiments with films of the Virgo cluster have shown that the noise per pixel in deep exposures is only 0.7 % of sky, enabling known objects to be traced out to an isophote around 27 Rµ. In addition, a preliminary survey has revealed several new galaxies with central surface brightnesses around 24 Rµ. With the digital coaddition of several films, we expect to be able to measure objects out to the 28 Rµ isophote and detect galaxies with central surface brightnesses as faint as ∼ 25 Rµ, i.e. below 3 % of sky.

Equipping the 105 cm Kiso Observatory Schmidt telescope with large CCD cameras has initiated a new phase for galaxy photometry studies performed with the telescope. As part of multi-wavelength studies deep multi-colour CCD images were obtained of various types of individual galaxies, as well as pairs and groups of galaxies.

Simple photographic techniques are used to enhance and combine many images of (mostly) bright galaxies made from plates in the archive of the UK Schmidt Telescope in Edinburgh. The purpose of this project is to reveal extended faint features of these objects that are less than 0.5 % as bright as the night sky. Presented here are the preliminary results of what we intend to be a substantial atlas. The early results suggest that a remarkably large number of apparently normal galaxies reveal unexpected features when very deep images are produced.