petrochemist

Joined: 27th February 2010

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petrochemist
cardiff_gareth wrote:
You guys need to get out more lol !!
But it's too dark now to be stalking damsels

If my internet sources are correctly interpreted this is the female Banded Demimoiselle (from just over a week ago):

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Female Banded Demoiselle damselfly? by Analyst 1, on Flickr

Comment by petrochemist posted on Damselfly? Identification Needed Please at 07/06/2011 - 23:08

petrochemist
Anvh wrote:
grahamwalton wrote:
I would guess that the K100d would be partially sensitive to infrared.
There is a filter infront of the sensor that filter IR out sadly

I've the same problem with the K10D but if it's a sunny day and you got a tripod you can do IR photography but it takes quite some long shutter times.
The K100d has quite a weak hot filter (the one in front of the sensor) It's not difficult to get shutter speeds that can be hand held even with the kit lens. (Playing around last week I took an indoor 720nm IR portrait at 0.7s f5.6 200ASA that was reasonably exposed - slight camera shake, but that would have been fine at 800ASA)
Getting them properly in focus is more of a problem, as IR focuses at a different point then visible light. This difference varies considerably from lens to lens

Comment by petrochemist posted on Shooting an Infrared Image at 07/06/2011 - 23:00

petrochemist
My dominant eye has change around over the years.
About 20 years ago (with prescription glasses) I found at a fair my shooting was MUCH better with my left eye. (Despite the awkward sighting being right handed)

For most of the last 5 years (without glasses), my right eye was the one for distance views whilst the left worked well for close up. I found with both open I could chose which eye to use depending on what I was viewing. (My options claimed glasses to correct my eyes to work together would have too much difference & give me headaches.)

Now my left eye has been sorted, and is again the better of the two for distance work. Both are now rated at 6/6 (20/20 in Imperial) but the right has slight keratoconus (noticeable only with pinpoint lights - stars etc). Unfortunately for reading both now struggle

Comment by petrochemist posted on Which eye? at 07/06/2011 - 22:46

petrochemist
fatspider wrote:


The first three are of the Banded Demoiselle,
Indeed, & a male, the female being metallic green without the bands on the wings.

Cracking photos

Comment by petrochemist posted on Damselfly? Identification Needed Please at 07/06/2011 - 22:30

petrochemist
Assuming your tripod has a standard 3/8 screw (or a 1/4-20 screw) then yes other heads will fit OK. As far as I know all tripods with removable heads use one of these threads.

My Manfrotto came with a reasonable pan head but I found it too fiddly for long lenses & switched to a video head. (Pan & tilt in 2 dimensions with an adjustable drag control) A gimbal head may have suited me better but I find the prices excessive.
On the Uniloc tripod I find a decent ball head works well. (Cheap ball heads are IMHO even less use than cheap tripods!)

The only panning head I use is built into my lightweight budget tripod - not suitable for even remotely demanding shots - so I don't feel qualified to advise on them.

Comment by petrochemist posted on Benro Panning heads at 30/05/2011 - 17:34

petrochemist
I like No 1. In a quirky way I think the eye looking out, together with the heads tilting towards each other, works despite breaking the usual rules.
Personally I think I'd prefer no 2 at the 17mm end of the zoom, making the people clearer and doing without the pillars. I'm not convinced that the fish-eye framing helps this shot, perhaps only because it is off-set, whilst the distortion (& DOF) works brilliantly in the first one.

Comment by petrochemist posted on fish eye... at 26/05/2011 - 20:06

petrochemist
The TC used here is only a budget 3x macro focusing model, but it still proves useful occasionally. This uncropped shot is of a a tiny spiderling only about 2-3 mm long, which my 100mm macro struggled with on it's own.

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I these situations I usually add a reversed 50mm as a close up lens, but for a change I tried out the macro TC (Having just tried it out with the 600mm reflex)

The additional focusing power of this TC gets in significantly closer. (Its designed to be used to get to 1:1 with a 50mm prime.)

Comment by petrochemist posted on teleconveter on a macro lens at 25/05/2011 - 20:14

petrochemist
Great set, though I'd prefer them without the dramatic tilts - Can't understand why that is fashionable!

Comment by petrochemist posted on IR photos at 17/05/2011 - 23:09

petrochemist
PM sent in case Oriel doesn't buy it.
I've been cursing the A setting of mine for a while!

Comment by petrochemist posted on FS: Pentax 50mm f1.7 A at 17/05/2011 - 22:56

petrochemist
My first two accepted were an owl & a par of butterflies, so it's not just winged creatures - more like the usual random factor...

Comment by petrochemist posted on PPG judges hate birds! at 14/05/2011 - 07:40

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