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bvanant

Member Since 01 Apr 2002
Offline Last Active Yesterday, 09:52 AM
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#388257 DIY - Make your own fiber optic cable for your underwater flash - works with...

Posted by bvanant on 09 October 2017 - 02:12 PM

Well, the 613 fiber cable by itself is quite expensive, in small quantities it is like $6/foot.  You can get it cheaper though if you need 500 meters worth. For me I make my own fiber cables because I like to mess around, not because of price so much.  In any case I buy the 2-hole bushings from Inon for $5 each (http://reefphoto.com...roducts_id=3932) and buy jacketed 1 mm fiber from Asahi for $1.25 per meter. If you use only one fiber then things don't work so well but if you use two fibers (one in each hole) you can get a 1 meter cable that works well with the Nauticam trigger and Inon or S&S strobes for less than $15.

 

Cheers

Bill




#385685 Can you use Nauticam silicone on Sea&Sea blue o-ring?

Posted by bvanant on 08 July 2017 - 12:51 PM

Not so much. There are silicone greases and fluorosilicone greases and each has specific uses. For example Silicone grease (the stuff in the big trident tub) can swell silicone o-rings and lead to troubles.  That is why we keep recommending either the Tribolube or Christolube (or Krytox if you can find the right one) since they are good for all types of o-rings.

 

Bill




#383705 How to get sharper corners when using E-mount 12mm Zeiss in Ikelite housing a...

Posted by bvanant on 30 April 2017 - 09:20 PM

Firstly, why are you worried so much about the corners. Your photo looks fine to me and unless you are pixel peeping why worry. Secondly you can shoot at smaller apertures (like f:16) but most likely won't help too much. Getting a bigger dome will help but at a cost and pain for travel factor. Using a diopter on the lens can often help and is quite inexpensive compared to a new dome.  One thing to check on is the corner sharpness of the lens on land; test it in the garden; it can't be much better UW than it is on land.

Bill




#382052 Oops... Did I just mess up my kit?

Posted by bvanant on 07 March 2017 - 08:50 AM

No worries; think about what forces are on the o-rings and seals. All commercial planes run around the equivalent of 1800 meters (6K feet) or slightly higher than say Denver. Taking your housing to Denver is not such a worry.

Bill




#381149 And you think UW shooters are obsessed...

Posted by bvanant on 01 February 2017 - 05:16 PM

Sort of like the psychedelic frogfish in a sunball

Bill




#377775 TTL flash trigger for M43 Panasonic/Olympus cameras?

Posted by bvanant on 13 October 2016 - 02:18 PM

I don't think anyone has a TTL flash trigger for the u4/3 cameras and it is not clear that the Nauticam trigger will fit in your housing, check this carefully.  Getting an LED to drive TTL is not terribly simple for optically triggered strobes. As you know typically TTL is obtained by the internal strobe sending out a weak signal then measuring the resulting intensity then sending out the true strobe signal.  Neither Olympus nor anyone else has published the inner workings of their TTL (except in some difficult to understand patents) so this is tricky.

Bill




#376140 Macro lens: Olympus 60mm, or Panasonic 45mm?

Posted by bvanant on 16 August 2016 - 07:49 AM

Clearly Bokeh is subjective but for me the Leica/Panasonic wins. We were just in the Northern Sea of Cortez and I shot a lot of brown cheeked blennies with both lenses in similar backgrounds, will try to post some later today.

Bill




#376097 Macro lens: Olympus 60mm, or Panasonic 45mm?

Posted by bvanant on 14 August 2016 - 04:20 PM

I have and shoot both. In my opinion the Bokeh on the Panasonic is much better than on the Olympus but the 60 is slightly sharper and focuses slightly faster for me (EM-1, Subal Housing). Neither are hard to handle in my opinion but neither are as simple as a 60 on FF. In terms of macro both lenses shoot 1:1 so the magnification (i.e. the macroness) is identical for either lens although adding a diopter to the 60 will get more mag than the same diopter on the 45.

 

 

Cheers

Bill




#375541 Inon S2000 for wide angle

Posted by bvanant on 26 July 2016 - 08:50 AM

Think about strobes for WA. The S2000 has a GN of about 20 and the YSD2 has a GN of 32. This sounds like a lot but in reality it is only one stop or so. NO strobes can light up a reef or a whale shark and any strobe can give you good CFWA stuff. WA photos are really about natural light and getting your composition correct.

 

For the s2000 with a GN of 20 (in air) or say 7 in water this means that 

GN = Distance (meters) * f stop

so 7 = distance (meters) * 11 (for f/11) so we can light up something about 2 feet (0.63 meters) or so away 

with the D2 and a water GN of 11 we can light up the same thing one meter away at f/11

so the D2 is only good for an additional foot of distance.

 

Hope this helps

 

Bill




#374377 Guide number of a strobe

Posted by bvanant on 06 June 2016 - 04:07 PM

The guide number of a strobe works like this. 

GN = Distance x F-stop

For a strobe with a GN of 20 (meters ISO 100) on land, I would estimate a GN of 10 (or less) underwater. If I want to shoot at f:11 then I can be around 0.9 meters or a bit less than 3 feet away.  That is why (even with strobes) the rules about get closer and closer are what they are.

Bill




#374097 OMD-EM-1 flash (FL-LM2) no longer works?

Posted by bvanant on 29 May 2016 - 02:04 AM

This flash is very suspect to random failures. On a recent Indonesia trip three separate flashes in different rigs all failed. I buy them on eBay and always carry a few spares.

Bill




#373561 Wee yellow things on wee black stuff.

Posted by bvanant on 12 May 2016 - 02:31 PM

A very interesting little beast with very cool sexual trimorphism. 

http://www2.nau.edu/...S.M. 1987_2.pdf

 

Bill




#369345 Best option to backup and view RAW pictures while travelling?

Posted by bvanant on 15 January 2016 - 06:40 PM

Laptop is my choice, lets me do real editing (haven't tried the surface pro) on the fly, macbook air is light and relatively fast, my wife uses it for video editing (Final Cut Pro X) as well.

Bill




#368955 Shooting 1:1

Posted by bvanant on 05 January 2016 - 08:48 AM

The 105 Nikon lens has a minimum focus distance of about 1 foot (30 cm or so) measured from the focal plane line on the camera body (not the front of the lens). At that distance you get true 1:1 i.e. a beastie 36 mm or so across fills the frame. What you should do  if you are interested is to mount your camera on a tripod and shoot a ruler at various distances from the ruler and you will see that even relatively large movements away (say an inch or 10%) you will still get 38 mm or so filling the frame. If you play that way you will find out how important (to you) that last little bit of magnification is.

 

Bill




#368740 Z-240 to Olympus PT-EP08 Optical Cable??

Posted by bvanant on 29 December 2015 - 08:25 AM

On the camera it looks like a standard S&S connector (just a straight plug). On the Z240 end you need the screw on cap. http://www.bluewater...vMt8aAsfj8P8HAQ

or something similar.

bill