Jump to content


londonsean69

Member Since 09 Apr 2007
Offline Last Active May 25 2012 06:57 AM
-----

Topics I've Started

Possible Egyptian visa changes

09 September 2011 - 08:09 AM

Well, this could really hurt tourism in Egypt :)

http://english.ahram...in-advance.aspx

Lighting with mini-dome

12 August 2011 - 09:00 AM

I am really struggling with lighting when using my mini dome :) Especially when shooting stuff right on the dome. I seem to be getting hotspots, and find it exceptionally difficult to evenly light a subject.

Does anybody have any pointers? I have tried dialling down the power and having them right next to the shade, out a bit, out further etc.
The vis out here (Bahrain) can be very soupy at times, lots of particles in the water.

It's an Ikelite housing, UWCamerastuff mini-dome (5") with 2x S&S YS110. I have 2 segment arms, so can use just one or two segments. I currently have the diffusers on all the time.

Thanks for any pointers

Sean

UWCamerastuff mini dome for Ikelite - mini review

08 May 2011 - 06:06 AM

Before I start please note;
  • I have absolutely no connection, financial or otherwise, with UWCamerastuff.com
  • I paid the list price for my dome.
  • This review is based on 3 shortish dives
  • I don’t shoot test charts

UWCamerastuff 5” dome
I was having a bit of a Google, and came across this website - Underwater Camera Stuff, where they were offering a 5” mini dome specifically for the Ikelite housing and Tokina 10-17mm lens. This piqued my interest so after a couple of emails I put my order in.

You can get one from here 5" Modular Dome for the ikelite modular port system

Dome ports
I know very little about domes and dome port theory, so all I can put here is my own opinion based upon my own results. For a much more in-depth article on mini domes, please see this by Alex Mustard - Thoughts on Mini Domes :: Wetpixel.com. His example images are a lot better than mine as well!

I have, and use, the Ikelite 8” dome. This is an acrylic modular dome. By modular, what occurs is you buy the dome and then add the correct port body for your lens, much like any other dome.
I have also had, and used, the Ikelite 6” dome. This is also acrylic, but they are not modular. You buy a dome per lens.

From my limited experience (around 20 dives with each Ikelite dome) I can conclude the following when comparing the Ikelite 6” & 8” domes;
  • Big dome is much easier for split shots
  • Small dome is much easier for travel (it is both lighter, and more compact)
  • Big dome gives much better corners (I have shot the Nikon 10-24mm lens through both domes – it may well have been better in the small dome had I used a dioptre)

So, why should I use a mini dome instead of the 8” dome I already use? In a word, travel.
The 5” mini dome is very small, yet gives (to my eye) a much better result than the 6” dome.

OK, enough uneducated waffle, what did I get, and what can it do?

Ordering – simple, email Bill and he puts you on the list for one of the next batch. No deposit was asked for, I paid (via PayPal) once it was ready for delivery. Bill is keen to point out that he is a one-man band, and he wants as much feedback as possible from users so that he can keep improving the product. VAT was payable on arrival, but have a chat with Bill for the customs bit.

What’s in the box? – 5” dome port and a new port lock (much nicer than the Ikelite version). Also in there is a neoprene dome cover, and a plug for the back of the dome port. Everything was very well packed, with the all important dome having an extra couple of layers of protection.

5” dome – its acrylic, and optically I cannot find any defects. I placed it over some fine-print newspaper and no matter what angle I viewed it from there was zero visible distortion. The dome has been designed to use with the Tokina 10-17mm fisheye zoom, and the Ikelite superwide port body. The dome also has a port shade fitted, although as it is a hemispherical dome, it is not possible to rest the camera dome down, as it protrudes past the shade. You can see this in the photos further down. The threads for the port body are good and tight, rubber strap wrenches are a must!

5” dome
Posted Image

Port lock – the Ikelite superwide port body fits in a different way to other ports, and has a locking kit supplied with it to stop the port rotating. The Ikelite kit is a piece of metal that screws into the side of the dome, stopping the dome rotating the port off its latches.
The version supplied by UWCamerastuff is much neater, and consists of a moulded piece of plastic, that is screwed into the focus light mount on top of the housing. This locks the port solidly to the housing.
The instructions suggest you secure the port lock using the longer set screw supplied with the superwide port body. Rather than remove this from my big dome port, I just used the threaded ball mount normally reserved for my focus light. I shall be removing this longer screw as I now know the new port lock works perfectly.

Port lock installed on port body (normally hidden by the dome)
Posted Image

Neoprene dome cover – this is Ikelite branded, and whilst I stand to be corrected, I think it may just be the standard Ikelite 6” cover, as it does have some excess material.

Dome port plug – obviously, an acrylic dome is prone to scratching. The neoprene cover does a good job of protecting the outside surfaces, but the insides are also vulnerable. To this end, Bill provides a plug for the dome, threaded to match the threads on the dome.
My initial thoughts on this were that it looked a little ‘rough and ready’, however after speaking with Bill, it seems he is trying a few different methods, as the plastics involved are pretty hard to glue. To be fair to Bill, they are only minor scratches, and I am probably being a bit picky.
As it stands, once the superwide port body is fitted, I leave it on whichever dome is currently in use, so the port plug resides on whichever dome is in storage.

Port plug
Posted Image

By way of comparison, here are some photos of the housing with the 8” dome, and the 5” mini dome fitted. I no longer have the 6” dome, so no photos of that on the housing, sorry.

8” dome installed – front view
Posted Image

8” dome installed – top view
Posted Image

5” dome installed – front view (port lock omitted)
Posted Image

5” dome installed – top view (port lock omitted)
Posted Image

5” dome installed – angled top view (port lock omitted)
Posted Image

Example images
I’m not a professional photographer, just an enthusiastic amateur, so make of these images what you will.
I did not have the chance to shoot all 3 domes back to back with the same lens under the same conditions, as such, I shall only be showing sample images from the 8” dome and 5” mini dome, both using the Tokina 10-17mm fisheye zoom.
For completeness sake however, I have also included a single image shot using the 6” dome with the 10-24mm lens, and a single image with this lens behind the 8” dome This is not a fisheye, and may well need a dioptre behind the smaller dome, so do not read too much into it.

Please note that these images are ‘real world’, as such the aperture varies, as does the subject matter. This isn’t exactly the most of scientific tests.

I have only shot a few 100 frames with the mini dome, and am still trying to work out lighting when the subject is right on the dome, so no comments on the actual image content please!
As I mentioned in the preamble, I don’t shoot test charts, I don’t really see the point. Instead, I have chosen a couple of images of typical reef scenes, shot at typical apertures (Note: as a result of Alex’s article I shoot the mini dome at a smaller aperture). I don’t care if a corner is soft when the lens is wide open as I don’t shoot wide open when underwater. I want to know how a lens/port behaves under the type of conditions I will be using it. For the pixel peepers I have also provided 100% crops from one of the lower corners (resampled to 72dpi).

10-24mm with 6” dome
Posted Image
10-24mm @ 10mm, 1/125 @ f/11

100% corner crop (bottom right)
Posted Image

Forum/thread style

04 February 2011 - 01:03 AM

Morning

When I logged in this morning, the display of threads has moved to a 'tree' structure, rather than a list of all the posts.

I much prefer the old style, is there anyway I can change my display settings? Or maybe my morning blindness means I can't see/find the option

Thanks

Sean