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Glasseye Snapper

Member Since 11 Oct 2005
Offline Last Active Jul 09 2016 06:04 AM
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Posts I've Made

In Topic: Avoiding Damaging Reefs

15 June 2016 - 05:08 PM

I personally strive for zero damage, while accepting that some damage is implicit even if only by increasing economic development near shore.

 

The closer you want to get to the reef the better your buoyancy has to be. So either keep a distance or perfect your buoyancy, although not necessary by PADI or other course.

 

Do not touch any LIVING thing underwater. One or two fingers placed on a carefully selected piece of dead coral just to stabilize, no force, is much better than jojoing and kicking your fins to stay in place. You could do this equally well with gloves and the whole no-gloves rule is imho just because people expect you to be more careful without them. If you ever see parrotfish scraping the corals you also realize that if corals could not handle any mechanical contact they would have long been extinct (not an excuse to be careless, just some perspective).

I don't like diving sticks, assuming you mean the metal pins, as you don't get any tactile feedback and you create a point-pressure unlike a finger with or without glove.

 

Buddy signals to help each other out of a tricky position sound complicated to me. You really should not get into such situations in the first place.

 

Tucking away any dangling pieces of equipment is a good point as are most of the others. In the rare cases that I do touch the reef it is virtually always my fin tips. Retracting your legs while stopping finning and using your hands and/or lungs to move away from contact works well.

 

I also make an effort not to kick up a dust storm when swimming close to sand substrate, but I have no problem touching or even lying on the bottom after ensuring it is "clean sand".

 

Bart


In Topic: Two fish from the Revillagigedos Archipelago

06 June 2016 - 04:19 PM

The first is a grouper. I am not familiar with those waters but the same species for the same location is shown here

 

http://www.alamy.com...s-59071706.html

 

and named starry grouper, Epinephelus labriformis. Many other images of this species have more obvious starry white spots so you may want to double check but my feeling is that it is correct.

 

bart


In Topic: Two fish from the Revillagigedos Archipelago

06 June 2016 - 04:19 PM

The first is a grouper. I am not familiar with those waters but the same species for the same location is shown here

 

http://www.alamy.com...s-59071706.html

 

and named starry grouper, Epinephelus labriformis. Many other images of this species have more obvious starry white spots so you may want to double check but my feeling is that it is correct.

 

bart


In Topic: teleconverter for sigma15mm

03 May 2016 - 04:45 PM

A similar question was raised last year (http://wetpixel.com/...l=teleconverter) but did not get answers. I hope you fare better as my reply won't count as an answer. I just checked out the tread to find out why anyone would want to do this in the first place. It is much easier to make a 24mm lens than a 15mm lens, so why would you add the extra size, weight, glass, and expense of a TC, which also reduces light captured by the sensor, to fake a 24mm and not use the real thing? I also seem to recall that canon teleconverters came with the message that they were designed for use with long focal length lenses and not recommended for wide angle lenses, although that may not be a real concern.

 

Bart


In Topic: Are people leaving micro four thirds?

03 May 2016 - 04:35 PM

Full frame sensors not only need physically larger/heavier lenses. They also need longer actual focal length for the same FOV as a smaller sensor. In turn, minimum focus distance tends to increase with longer actual focal length. So m43 lenses tend to focus closer than their equivalent-FOV full frame lenses. In many cases that helps UW use by allowing you to get closer to your subject.

 

Bart