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A Guide to Underwater Wildlife Video & Editing: Part 7

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Underwater Video

Read Part 6 here.

A part serialisation of a book by Jeff Goodman

PART 7: Flat & Dome Ports

Having paid good money for your camera and housing, it would be a shame to now spoil your image quality with a cheap port.

The optical properties of your port are as important as the lens of your camera. A low quality port would be like putting the wrong pair of spectacles on a person, so although they could still see well enough, the images would be slightly soft or degraded.

Once again you usually get what you pay for. Often the problem of choosing your first port is solved for you by the housing manufacturer in that a particular housing and supplied port will be specially designed for optimum results with a particular camera and lens. It is always worth grilling the sales person that this is the case for the set-up you are interested in (In the semi-professional range of cameras and above, you can of course change camera lenses. It then becomes very important to use a compatible port).

No single port will cover all the types of filming you may like to do.

There are 3 main port types:

  1. The flat port which is mainly useful for macro work and good close ups.
  2. The standard dome port which covers most applications.
  3. The wide angle dome port for videoing ultra wide angle.
Underwater Video

Flat Port

Underwater Video

Dome Port

 

 

 

 

 

 

The flat or macro ports are great for filming close ups and macro but because of the refractive index effect as previously mentioned, this port will decrease the natural angle of coverage of the lens and so increase the apparent image size. These ports would not be the best for videoing large subjects such as whales or wrecks, especially if the water visibility is minimal and you have to get really close to see anything at all.

The standard dome port is a good option for covering a wide range of subjects and is probably the most widely used. These standard dome ports will compensate for the 1/3rd angle of coverage loss and restore your lens to normal coverage.

The wide angle port provides the maximum angle of coverage when used with a wide angle lens and is good for getting close to the subject but maintaining a wide perspective. These are particularly useful in temperate waters where the visibility may generally not be so clear. Many manufacturers of underwater housings put in a standard port by default.  More expensive housings will allow you to change ports which in effect is the same as changing lenses. Another option for some housings is to use a ‘wet’ wide angle adaptor which can be added to, or taken away from the flat port while still underwater. These ‘wet’ ports are very versatile but there is a small drop in quality when compared to a prime wide angle port.

Fisheye lens & port

Underwater VideoA fisheye lens and port give an even greater angle of coverage, but does so with a high degree of distortion. This will vary in degree from lens to lens. The effects can be quite dramatic and are usually better used with stills photography than video.

Zooming through a dome port

Not all dome ports, especially the cheaper ones, will facilitate a zoom and at the same time, keep focus. Auto focus can sometimes compensate for this but it is not guaranteed. And remember, if you do zoom in, then the depth of field will decrease. Generally zooming while actually filming can be very off-putting for an audience and so unless there is a very good reason for doing this then I would suggest you mainly use the function for re-sizing and framing your shot.

Scratched Ports

Underwater VideoA scratch or mark on your port can be a real pain. Scratches are more noticeable on glass ports than on Perspex ones. This is because Perspex or acrylic is roughly the same refractive index as sea water and so scratches are effectively filled by the water and visually removed. But with glass the refractive index is different and as light passes through a scratch it behaves differently from the rest of the port glass and becomes noticeable. Under normal front, side or top-lit situations, a scratch may not be noticed but may very quickly become apparent when back-lit. With glass I’m afraid it is time to change your port. With Perspex there is the opportunity to buff the port with ‘wet & dry’ to remove light scratches. This will take hours of patient work.

In short, take care of your ports. Glass is tougher than Perspex but is far more expensive. Your choice. If you can afford it, go for glass.

Condensation

Condensation and fogging in a housing can lead to missed shots and great frustration and, of course, it doesn’t become noticeable until you are underwater. The problem can occur when there is a slight amount of moisture in your housing and then that housing is put in the heat of direct sunlight. The moist air in the housing, upon being put into relatively cold water, will immediately condense on the thinnest and coldest part of that housing, which is going to be at the centre of the dome port.  It rarely happens with a flat port but it is not impossible. So, you jump in the water hoping for a great video session and all you get is foggy day shots. You can see the condensation right away, but just occasionally, if you are not paying attention and the amount of moisture is very slight, the effect will be to soften the focus of your image. You may think all this is obvious but be vigilant.

The solution is to make sure your camera and housing interior are thoroughly dry and you do not leave your rig out in the hot and direct sun at any time, especially while you are kitting up. Keep the housing shaded until you get in the water.

Next time we look at Colour Bars and Monitors.

Jeff Goodman is the Editor-at-Large for Scubaverse.com with responsibility for conservation and underwater videography. Jeff is an award-winning TV wildlife and underwater cameraman and film maker who lives in Cornwall, UK. With over 10,000 dives to his credit he has dived in many different environments around the world.

Competitions

WIN a Beuchat Air Light Bag!!!

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beuchat-logo-1-300x58.jpgFor this week’s competition, we’ve teamed up with our good friends at Beuchat to give away an Air Light Bag!

The Air Light Bag from Beuchat is a practical travel bag that takes up minimum storage space.

  • Material: 600 denier and 1,000 denier nylon/PVC
  • Soft roller bag, easily stored in its mesh bag
  • Internal retaining straps
  • Zip fastener with eyelets for padlocks
  • Side compartment for fins
  • Outer document pocket with coated zip and carry strap
  • Backpack style straps concealed behind the foam back-plate
  • Drainage vents
  • Red over-moulded wheels; detachable wheel block

To be in with a chance of winning this awesome prize, all you have to do is answer the following question:

In a recent post on Scubaverse.com (which you can read here), we reported that Mexico is to host the first annual Cancun International Boat Show and Marine Expo this year. But when is the event due to take place?

Is it:

  • A) 9th – 11th July
  • B) 16th – 18th July
  • C) 23rd – 25th July

Answer, A, B or C to the question above:

Beuchat Air Light Bag February 2021

Competition
  • Enter the country you live in
  • Terms and Conditions: This competition is open to all visitors to www.scubaverse.com except for members of the Scubaverse team and their families, or employees of Beuchat and their families or employees of Suunto Diving UK and their families. A valid answer to the competition’s question must be entered. If no valid answer to the competition’s question is entered, your entry will be invalid. Only one competition entry per entrant permitted (multiple entries will lead to disqualification). Only one prize per winner. All prizes are non-transferable, and no cash alternative will be offered. In the event that the prize cannot be supplied, no liability will be attached to www.scubaverse.com. When prizes are supplied by third parties, www.scubaverse.com is acting as their agents and as such we exclude all liability for loss or damage you may suffer as a result of this competition. This competition closes on 07/04/21. The winner will be notified by email. The Editor-in-Chief’s decision is final.

  • The following fields are optional, however if you fill them in it will help us to determine what prizes to source in the future.

  • Date Format: MM slash DD slash YYYY
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Miscellaneous Blogs

Jeff chats to… Jill Heinerth – underwater explorer, author and presenter (Watch Video)

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In this exclusive Zoom interview, Jeff Goodman, Scubaverse Editor-at-Large, chats to Jill Heinerth.

Jill is one of the world’s premier underwater explorers, and the first person to dive inside iceberg caves. According to filmmaker James Cameron, “More people have walked on the moon than have been to some of the places Jill Heinerth has gone right here on earth.”

An acclaimed polar explorer, cave diver, author, speaker, filmmaker, and climate advocate, Jill is the first Explorer-in-Residence of the Royal Canadian Geographical Society. She is the inaugural recipient of the Sir Christopher Ondaatje Medal for Exploration and Canada’s Polar Medal.

Jill leads expeditions into extreme environments to advance scientific and geographic knowledge. Her projects have been broadcast on the CBC, BBC, PBS, Discovery Channel, and television networks worldwide. Jill was announced as the recipient of the William Beebe Award from the Explorer’s Club and was inducted into the International Scuba Divers Hall of Fame in fall 2020.

Her bestselling book INTO THE PLANET – My Life as a Cave Diver  has drawn acclaim from the New York Times, Wall Street Journal, NPR, and O Magazine. Heinerth details her journey into the extreme world of underwater cave exploration, where she has had to overcome fear in order to go where no one has gone before.

Find out more about Jill and her work at: www.intotheplanet.com


Rather listen to a podcast? Listen to the audio HERE on the new Scubaverse podcast channel at Anchor FM.

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Competitions

Explore the amazing triangle of Red Sea Reefs - The Brothers, Daedalus and Elphinstone on board the brand new liveaboard Big Blue.  With an option to add on a week at Roots Red Sea before or after. 

Strong currents and deep blue water are the catalysts that bring the pelagic species flocking to these reefs. The reefs themselves provide exquisite homes for a multitude of marine life.  The wafting soft corals are adorned with thousands of colourful fish. The gorgonian fans and hard corals provide magnificent back drops, all being patrolled by the reef’s predatory species.

£1475 per person based on double occupancy.  Soft all inclusive board basis, buffet meals with snacks, tea and coffee always available.  Add a week on at Roots Red Sea Resort before or after the liveaboard for just £725pp.  Flights and transfers are included.  See our brochure linked above for the full itinerary.

This trip will be hosted by The Scuba Place.  Come Dive with Us!

Call 020 3515 9955 or email john@thescubaplace.co.uk

www.thescubaplace.co.uk

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