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Monochromatic (∆λ ≤ 10Å) images have been obtained for seven large (2 − 10 arcmin) Abell planetary nebulae. From this deep survey, we found 4 to have normal bipolar shapes, whereas 3 have truly spherical shells. The structures of these nebulae are discussed using the absolutely calibrated intensity maps in Hα, [N ii], and [O iii]. An attempt to derive ionized mass using our (dereddened) measured absolute flux as a function of distance to the PN is also given.doi:10.1051/aas:1999107 fatcat:zfj3zkbyavfkbjfciijuds2rea