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Paul Kay

Member Since 27 Nov 2003
Offline Last Active Yesterday, 02:02 PM
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Posts I've Made

In Topic: Housing maintenance

Yesterday, 01:57 PM

FWIW, Seacam recommend 300 dives as far as I can remember. That said if housings are used heavily in chlorinated water (swimming pools) then they need short service intervals as the chlorine may damage nitrile 'O' rings (I've seen an 'O' ring disintegrated after very, very, very extensive pool use - fortunately the second kept the housing dry and the control itself became progressively stiffer forcing the issue of servicing. And I do know of a friend's housing which I suspect may well have done over 1000 dives before factory servicing!


In Topic: Half and half rig flotation

21 April 2017 - 12:56 PM

Hi Pete

 

Half and half in mangroves sounds fun - different from the Menai today anyway.


In Topic: What gear for 120-130m?

09 April 2017 - 10:13 AM

Without a Seacam hat on (I supply Seacam in the UK), they are used to 120m as Seacam sell modified items for this depth. I believe (from what I have heard) that Seacam have been used at 150m. Probably your best bet is to query manufacturers and see what depths they are aware of their equipment being used to. I suspect (I may be wrong) that most equipment is simply not pressure tested to more that 10bar and although the seals may well be ok beyond this, some parts may not operate correctly (they may tighten or push in) or be overstressed beyond this.


In Topic: Any hands on experience with Nikkor 20mm 2.8D ?

23 March 2017 - 04:57 AM

 I understand that this isn't the ideal lens to go buy for UW photography, or the most popular choice for focal length (and fixed on top of it).

I really don't know why. I find fixed focal length lenses make you really think a lot more about how you shoot. I've used 20s, 24s and 35s underwater and I'm thinking about using a 28 in the near future. Many are excellent lenses and can be set up to be very good underwater. Limiting, perhaps but actually are (as above water) a very good discipline, and can give a better appreciation of how to use a specific focal length (and FWIW I've not shot on a zoom for about 5 years below or above water and I do think that this has improved my photography).


In Topic: Any hands on experience with Nikkor 20mm 2.8D ?

21 March 2017 - 09:33 AM

Caveat - I-ts a long time since I used a 20mm f/2.8D Nikkor underwater but I used to and I liked it well enough and it should still work well enough if situated correctly behind a reasonably sized dome port (Seacam, which I supply, certainly suggest that it is ok behind both the WidePort and Superdome, and I'd guess it will work ok behind the CompatPort too). Basically a lens with a 90 degree field of view is about the limit of what used to be considered viable - in the (film) days when smaller domes were more the norm - although often they were used with diopters behind smaller ports. Today we are more critical but you should be able to get it to work well enough. If its not 'supported'-  I assume that simply means that there is no recommended port/extender combination - this is possibly because fewer people use fixed focal length lenses these days and little data is available (I'm surprised nobody who uses one has posted). On the Seacam it simply sits behind the port with no extension and this is where I would start. Personally I prefer fixed focal length lenses and would happily use this 20mm lens if I shot on Nikon - Canon's offering has not impressed me above, let alone below water!