22 August 1980 Photographic Image Intensification By Neutron Activation Of Gold Toned Negatives
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Proceedings Volume 0232, 1980 Intl Optical Computing Conf II; (1980) https://doi.org/10.1117/12.958874
Event: 1980 Technical Symposium East, 1980, Washington, D.C., United States
A gold-toning neutron-activation process has been developed at NRL for the purpose of intensifying or amplifying the contrast in extremely weak images in photographic negatives where the exposure level may be as low as 1.5% of optimum. Such contrast enhancement of photoreconnaissance and intelligence films allows the recovery of image information which may be taken under adverse lighting or obscured in the shadows and which might otherwise be lost by conventional methods using chemical/photographic or densitometer/computer techniques. The gold-toning neutron-activation process differs significantly from the usual nuclear methods of photographic image enhancement in two important ways: (a) A nonradiochemical toning solution is used to gold plate the image silver grains before activation. This procedure eliminates all hazards of handling radioactive solutions. (b) The neutron activation of the gold image is superior to either direct neutron activation of the silver image or radiochemical toning of the silver image both with regard to the efficiency of image activation and the speed and ease of producing autoradiographs. Recent results of the optimized gold-toning neutron-irradiation technique clearly demonstrated the recovery of image information which was not detectable by standard densitometer computer scans of the original film at the 1.5% exposure level. Such analog nuclear techniques can complement the power and flexibility of computer enhancement by significantly extending the lower limit of optical detection.
© (1980) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Clarence D. Bond, Clarence D. Bond, } "Photographic Image Intensification By Neutron Activation Of Gold Toned Negatives", Proc. SPIE 0232, 1980 Intl Optical Computing Conf II, (22 August 1980); doi: 10.1117/12.958874; https://doi.org/10.1117/12.958874

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