Avast Marine's top down camera portholes

[Brie]

I FINALLY got these for the using in the shop, after much pestering. I gotta say, it makes life ALOT easier photographing corals... They're awesome!! I love the fact that they make a macro size and a normal 50mm-ish size... With the macro size you can stick a good 8" or so into the water to get closer to your subject, or take a pic at different angles.

I'll get some pics up tomorrow that I took using both of them... Seems I took all of the pics of my memory card onto the work 'puter...

But yeah, just my 2 cents, these things are awesome and worth the money IMO for people trying to shoot colonies or corals top-down. MUCH better/easier then trying to do it through a standard lookdown box.

Macro size: AVAST Marine Works - Top-Down Porthole, Extra Long - Product Details

Standard size: AVAST Marine Works - Top-Down Porthole - Product Details

Quick cell phone pic of both of them next to my camera

 

[returnofsid]

OOOOhhhhh, I've been looking at getting one of those, for almost a year!! I've also considered making one, myself. But for the price of these things, I don't think I could make one. They're actually very affordable. Can't wait to see pics, taken with one!

 

[Sculpin]

Nice! For macro you mention the longer porthole, so I'm guessing you are shooting the 105mm?

Thinking the shorter one would work well with my 60mm.

 

[Brie]

Nah, its only a 90mm... The porthole is alot longer then the lens, to allow for external movement(instead of the internal focusing macros $$).

and yeah, i'm sure the shorter one would work for a 60.. Only thing to watch is how far out your lens extends... The acrylic scratches really easily.

 

[Sculpin]

To play it safe, it might be worth going with the longer porthole, which would also allow dipping it further into the tank. Only thing to consider for more wide angle lenses is possible vignetting on the longer porthole.

I assume there is no problem with the screws tightening enough to hold thinner lenses on either system?

 

[Faciosity]

I made one with a 14" plastic tube and a thin piece of acrylic. Works pretty good.

 

[Brie]

To play it safe, it might be worth going with the longer porthole, which would also allow dipping it further into the tank. Only thing to consider for more wide angle lenses is possible vignetting on the longer porthole.

I assume there is no problem with the screws tightening enough to hold thinner lenses on either system?

yeah I wouldn't use the longer porthole with a <55m lens. It would definately show in your image, and even at 55m prolly show some dark vignetting.

Yeah the screws are LONG. Can definitely hold any size lens, from huge to micro. The only problem I came to is making sure you tighten the screws so that the lens is completely level with the porthole bottom so your image isn't distorted or blurred. And the lens does move around a bit with the deep porthole because of its buoyancy, so some occasional adjustment is needed.

 

[returnofsid]

So, when do we get to see pics taken with these?

 

[Brie]

Crap, I totally forgot. It was so busy on friday at the shop that I didn't even have a chance to sit down at the computer, and then didn't work on Saturday... So i'll try to get some uploaded tomorrow.

 

[Brie]

Ok guys, here ya go. You asked for it. LOL.

As usual, click on pic for full size version.

 

[J-Ranko]

Whoa, lovely shots, Brie! Are those new arrivals? I don't remember seeing those at the store.

 

[Brie]

Thanks.

Only 3 or so are new.. The rest have been there a while...

 

[spllbnd2]

Very cool. I'm going to need to get me one of those.

 

[bodycology21]

Those look awesome

 

[returnofsid]

Very nice!! One question, on this photo, the focused field of view, seems to be perfectly circular. Do you think this is because of the look down tubes? It almost looks like you used a filter, to blur outside the perfect circle, though I'm sure you didn't.

 

[returnofsid]

Very nice!! One question, on this photo, the focused field of view, seems to be perfectly circular. Do you think this is because of the look down tubes? It almost looks like you used a filter, to blur outside the perfect circle, though I'm sure you didn't.

 

[Somethings Fishy]

Wow, i love it! wish my underwater vids were that clear!!!!!

 

[Brie]

No, its just a very wide aperture causing alot of bokeh. I think I was at f/4.5 or 4.0. All of the photos were taken with the tube, and they have varying degrees background blur. I think maybe the reason the in focus vs bokeh area of the chalice macros is due to the level plain of that hump... If it had more of a point to the front, it'd like just have one or two eyes in focus... But the front of the hump was pretty flat so a group of the eyes were in focus. Hope that makes sense. LOL.

 

[Brie]

Check these out.. they might give you some better info then what i'm able to explain. lol.

Aperture - Wikipedia, the free encyclopedia

Bokeh - Wikipedia, the free encyclopedia

 

[NC2WA]

Nice, Pretty darn clear pics.