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Scientific Illustrations
Holopogon sp.
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- About this illustration:
- This illustration depicts the male of an undescribed species of Holopogon (Diptera: Asilidae) with a metallic reflective surface on the dorsal surface of the abdomen used during mating behaviors.
- The reflective surface is actually made up of rows of small scale-like hairs, shown on the right.
- notes about the figure on the left:
- specimen was collected at Brackenridge Field Lab, University of Texas at Austin; drawing was made from a dried specimen mounted on an insect pin.
- used the camera lucida on a dissecting microscope at low magnification to create pencil sketches of the body and head
- a small ruler was used to draw a scale bar
- sketches were placed on a small portable light table and traced in pencil on vellum, combining both sketches and the scale
- a 35 mm macrophotograph of the specimen was used as a reference to fill in detail
- drawing was then traced with pigma permanent ink pens (sizes 005 to 03) and stippling was added
- labels for the image and scale bar were added by tracing a printout from Microsoft Word
- notes about the figure on the right:
- source image was a scanning electron micrograph taken in 1997 by the author at the University of Texas at Austin
- photograph was scanned into Adobe photoshop and enlarged to an appropriate size; the image was cropped to a circle
- the scale bar was preserved from the original micrograph.
- a printout of the photoshop image was placed on a small portable light table and traced in pencil on vellum
- the original photomicrograph was referenced to fill in detail
- drawing was then traced with pigma permanent ink pens (sizes 005 to 03)
- scanned with an ASTRA UMAX 1220U scanner into Adobe Photoshop
- scanner is ~5 years old
- scanning method: single pass with color CCD
- optical resolution: 600 x 1200 dpi
- data output: 36 bit (color), 12 bit (grayscale)
- Step 1: make sure the scanner bed is clean!
- Scanned as a grayscale image at 300 dpi
- In photoshop, I:
- adjusted the brightness/contrast to make the page bright white
- used the transform tool to rotate align the image properly
- used the eraser tool to remove specks and smudges
- cropped the image and saved as a JPEG at 72 dpi
- made a thumbnail version of the image
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Helicopsyche sp.
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- Notes about this image:
- source image was a scanning electron micrograph taken in 1998 by the author at the University of Texas; original specimen was collected from Dolan Creek, Val Verde County, Texas
- photograph was scanned into Adobe photoshop and enlarged to 8 x 10
- the scale bar was redrawn from the original micrograph.
- a printout of the photoshop image was placed on a small portable light table and traced in pencil on vellum
- the original photomicrograph was referenced to fill in detail on the insect and select portions of the case
- drawing was then traced using pigma permanent ink pens (sizes 005 to 03)
- labels for the image and scale bar were added by tracing a printout from Microsoft Word
- Scanned into Adobe Photoshop as a grayscale image at 300 dpi with an ASTRA UMAX 1220U scanner
- In photoshop, I:
- adjusted the brightness/contrast to make the page bright white
- used the eraser tool to remove specks
- cropped the image and saved as a JPEG at 72 dpi
- made a thumbnail version of the image
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