Translate

Friday 24 January 2014

A Beautiful Day In The Tropics

A recent trip to the Daintree Region north of Cairns was very pleasant. It is the height of summer in Australia and school children are just about to return to their studies and there are not many people about. For some, this is the best time to visit.
Miles of beach with not a soul around.
The water is warm, about 30C, but there are reasons to not enter. Stinging jellyfish are common this time of year and at least one species is fatal if encountered. And there are plenty of them about. Most public beaches have stations with bottles of vinegar to be used if you have the misfortune to be stung. Medical treatment is required if you do get stung.

But look carefully at the middle of the above photo. See anything?
Looks like a log, no? NO. It's Mr Croc cruising 50-100 metres offshore and heading to Cooper's Creek.

Buck Richardson photo

He's a biggie. We estimate more than 4 metres in length. Oh yes, that's another reason not to go into the water in the northern tropics of Australia.

Sunday 12 January 2014

Photography Tricks

My colleagues alan Henderson and Piotr Naskrecki use a variety of techniques to enhance photos for various uses. One method they use is good for taxonomic studies has value in general education. I thought I might share it as I use it from time to time and it is incredibly simple and quick. And since everything is done quickly in this day in age, "quick" might be the operable word.

The equipment is simple and not costly.

Remember: click on the photo to enlarge it.

 A plastic dishwashing bin is all you need to get started. Just toss the insect in the bin. Usually it will sit still for a few seconds or minutes and you can get photos as it adjusts to this environment.



It is cicada season in Australia and there are at least a dozen species that come to the lights here and a few more that never do.

This tessaratomid comes around on ocassions. The flat surface of the body is ideally designed for this photgraphic technique.

It allows you to see some of the important characters on this female of Teleogryllus commodus.

So what's the trick?
Once the photo is taken, adjustments need to be made since the background will be uneven and have highlights, shadows and bits of dirt etc.
Imprints on the bottom of the plastic and highlights can be removed using a number of tricks. The contrast/brightness controls can be adjusted to reduce the highlights and shadows. In Photo Shop the "curves" function in the "adjustments" category can remove most of the problems seen above and the "Smudge" tool can be invoked to get rid of spots and dust that might cling to the specimen.
 Personal preferences dictate whether a shadow might be useful or not
Same photo with shadows eliminated using "curves" in Photo Shop. (By the way, this seems to be a "click beetle year". Every night several species come to the lights. Some of the tiny ones come in huge numbers.
Stalk-headed flies make their appearance in the wet season when there is plenty of fruit for them to eat. To reduce their tendency to fly, a few minutes in the fridge slows them down. I have left the shadows here as it seems to make the photo less clinical.

These are very weird flies with the eyes of the males on the end of stalk.

Raspy Crickets, family Gryllacrididae, are lovely creatures with wonderful colours and patterns that tend to disappear in dry-mounted specimens. This is an ideal way to illustrate these insects with a minimum of fuss. You can use "photo-stacking" for an even better photo but this takes time.
 This may be too "flat". Use of the contrast/brightness control can tame it a bit.
So how do you look at the more "private" parts of the insect that may help you to identify it or use in a taxonomic publication.

I kill the specimen in ammonium carbonate (the smelling salts of the boxing and cage-fighting pastime).  This leaves the specimen very pliable and you can manipulate it into a desired position. Above is the "before", below is the "after".


Below are a few more examples of the results of using this simple photographic technique.

Brentid weevils are very photogeneic and cooperative. The "bits" on the legs are parasitic mites.
 An meloid beetle in the genus Zonitis.
Monteith's LEaf Insect, Phyllium monteithi comes to the lights a few times each year. This is a male. Females have not been seen at my place in Kuranda.
Some cockroaches are more amenable to this form of photography. This adult female Calolampra species just sat in this position for several minutes while the photo was taken. Males would have flown off instantaneously.

This little cricket measures about 4 mm in length. It is a female as indicated by the protruding ovipositor. It lives on the rainforest floor in leaf litter. It colours and patterns can be appreciated using the photo techniques discussed above.

But some folks never cooperate. This live weevil remained in this position for 18 hours before we both gave up and I released him back into the rainforest.

So wat doya think?