Core_5: riordan/Basic_V0/Core, $stg_pt = , $ident = 10809, PHP: 5.6.31

Core_29: Call load_info in Ld_input to load Cory_V0/Site.ndx
Core_31: $ndx_file has 64 entries
Core_58: Load Cory_V0/Albums/Curious/Folder.ndx
Core_145: $item = 4, $level = 1, $ent_id = 09, $wkg_item = 9
Core_196: Class = W Format = t, Including Format_defs.php
Curiosities/
Core_236: $image = , $img_pfx = corybas.com/, $act_pth = Albums/Curious/
Core_237: $image = , $img_pfx = corybas.com/, $act_pth = Albums/Curious/
Core_239: $format = t
$FDF['hdr'] = 1
$FDF['style'] = 1
$FDF['ftr'] = 1
$FDF['align_h'] = left
$FDF['align_v'] = top
$FDF['index'] = 0
$FDF['proc'] = Rnd_page.php
Core_240: $item = 4, $level = 1, WSE = 31, VSL = 16
Core_242: $incl_pth = Cory_V0/Albums/Curious/, $img_pth = corybas.com/Albums/Curious/, Temp_dir = , Fcb_dir = , Des_dir = , Hlp_dir = , Sys_dir = Basic_V0/, Home_dir = Cory_V0/, Utl_dir = , Is_local = 0, Sv_dsb = , Trusted = , Format = t
 
Core_301: $image = , $img_pfx = corybas.com/, $act_pth = Albums/Curious/
Core_302: $dvflg = , $item = 4, $level = 1, $format = t, $hdr = 1, $hdr_ht = 50, $style = 1
Core_303: Mnu_prc =
Core_304: Ftr = 1, Ftr_ht = 50
Core_305: Hdr_ht = 50, Body_ht = 650, Body_sp = , $body_sph = 640
Core_321: $format = t, $hdr = 1, $hdr_proc = Std_hdr.php, including Std_hdr.php
Home

Curiosities

Core_332: Error = , Including Basic_V0/Rnd_page.php
Rnd_P_71: Include Cory_V0/Albums/Curious/Aliens.php, Home = , Ident = 10809

1. Floor at the back door

Camera in normal mode

Early in April 2018 I was sweeping the kitchen, and when I swept in font of the back door and left the pile of dust in a sunlit spot I noticed some very small spots running back towards the door.


2. 'Aliens'

Normal mode; Maximum focal length

I was intrigued, and when I looked by the door I noticed that there were a number of tiny spots (which I presume are some sort of mite) wandering around. The floor is vinyl, with a glossy surface, and near the door it reflects the light from the sky, and if I look there the mites appear as black spots. There are lots of tiny spots of dirt on the floor, so I can only pick out the bugs if they are moving. There is a dark band near the door and they disappear when they enter this, so I can't tell if they are coming in somewhere there. They also disappear if they get near the benches, and they just seem to be wandering around, not going anywhere in particular.


3. Enlargement of 2.

(Dots moved together)

I don't know what they eat; I tried putting spots of honey, cheese and assorted food crumbs on they floor, and an hour later 2 had drowned in the honey, but the rest were ignoring everything. I decided to try to photograph them, and got out my Pentax X90. It is an excellent camera for photographing scenery and flowers (if it's not windy), but has difficulty coping with moving objects, and poor light. It weighs only 430 grams, has a 26:1 zoom range (focal length 4.6 - 120mm: equivalent to 26-675mm on a 35m), and a macro mode which will focus down to 10mm.


4. Bug

Length ~2mm

However it does not do well in poor light, or with moving targets, as it is slow to focus. I call it my delayed action telescope; I can photograph the You Yangs (hills on the other side of the Bay, and then zoom in on a distant water bird which is completely invisible in the first photo, but I can't see any real detail until I upload the images and look at them on the computer. The camera is not well suited to photographing the bugs - there aren't that many of them, they don't like to be in the sun and you can't use the flash in macro mode, and they zip around erratically at relatively high speeds, so it is hard to follow them. It would be useless to try to use a tripod so I have to hand hold the camera and hope for the best. The 'tile' in 2. is 65mm wide.


5. Another bug

Length ~1.6mm

Photos 1-3 were taken in normal mode against the light, so although the vinyl is a redddish color it does not show. The remaining photos were taken in macro mode, and revealed that the pattern on the vinyl is very obviously screen printed. The mites are a greenish yellow color which does not show up well against it, making everything that much harder. I must have taken at least 60 photos, but only got 4 or 5 reasonably good ones. As I was hand holding the camera every photo was a different magnification, and at a slightly different angle, and there is significant distortion in the lense.


6. Juvenile

Length <1mm

However the pattern in the vinyl gave me a scale I could use to measure the insects, so I photographed a ruler on the floor to measure the pattern, and worked out how to print each photo at the same magnification. The scale on the photos is 4mm long. I soon noticed there were some even smaller juvenile insects, and eventually found that the size varied from less than 1mm to about 2mm. Once the insects get off the bright area they are almost impossible to see, but one morning I noticed one coming into the room, and managed to follow it several meters into the laundry. However this was very painful as I had to keep my bad neck at an awkward angle, and if I took my eyes off it for a moment, or it stopped for more than a few seconds, I would lose it. I have not caught them misbehaving, and I doubt if I can discover much more about them, so I will abandon my research.

ps (26.4.18). Yesterday I dug up another clump of carrots, and before I went in for dinner I pulled off the leaves, and left them on a bench beside the back door. This morning, when I picked them up to put in the compost, there were dozens of mites running everywhere. Apparently they live outside, and like carrot tops.

Core_344: Include Std_ftr.php
 © Roger Riordan 2004-2018

Alien invasion

(Unknown mites)