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A series of digitised images from in-line holograms of the dinoflagellate Ceratium tripos. These hologram images showing different individuals in a variety of poses were recorded with a ruby laser (at 694 nm) and replayed with HeCd at 442 nm. The image magnification (for full capture images of 768x501 pixels) is
Width = 1040 micrometres x Height = 1025 micrometreswhich suggests that there is some anamorphic magnification in the Link109A with the RCA Ultricon tube.
The objects are typically about 200 µm long.
Peter Hobson
The camera shifts away from the best focus in increments of 0.50 mm. These hologram images were recorded with a ruby laser (at 694 nm) and replayed with Ar-ion at 514 nm. The object is about 200 µm long, and the change of image with defocus is very nearly symmetrical on either side of the "best focus."
Peter Hobson
These hologram images were recorded with a ruby laser (at 694 nm) and replayed with Ar-ion at 514 nm. The object is about 300 µm long (measured vertical projected length on the replayed image is 310 µm), and the change of image with defocus is very nearly symmetrical on either side of the "best focus."
Peter Hobson
Anyway, I've recorded some images of the rather well-known zooplankton image we all know and love. The image was replayed using a krypton laser at 647nm, and there are some residual aberrations in the image - with coma being the most noticeable.
The first series of images is showing the effects of variying the illumination beam diameter, effectively changing the f-number of the system. The maximum diameter is 59mm, and I've recorded a number of images at various apertures down to 7mm diameter without changing any other parameters. ( I've tried to make them a bit brighter as the aperture is closed. JJN)
The second series of images are through the focus images at an aperture of 38mm diameter, which was what I judged as giving the best overall image on the TV-monitor. These were taken at 0.2mm intervals over a +/-2.0mm range, and at 1.0mm intervals up to +/-5.0mm.
The images were recorded using a Ruby laser at 694nm. They were replayed using a Krypton laser at 647nm. The incidence angle on the plate is 59°20' from the plate normal. The incident light at the plate during replay is approx. 180 µWatt/cm2.
Helge Nareid
A series of digitised images from in-line holograms of the diatom Asterionella Formosa. These hologram images showing different individuals in a variety of poses were recorded with a ruby laser (at 694 nm) and replayed with HeCd at 442 nm.
Peter Hobson
A series of digitised images from an in-line hologram of Tetrahymen. These images cover a region about 1400µm wide by 1000µm high and were recorded with a ruby laser (at 694 nm? PH076) and replayed with HeCd at 442 nm.
The first set of images shows a number of different individuals. The second illustrates how volume holography allows us to gauge the spatial relationships between the organisms: the images show the the same area of the hologram at a series of planes in depth, each corresponding to a different individual.
Henry Nebrensky