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bvanant

Member Since 01 Apr 2002
Offline Last Active Today, 04:25 PM
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#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




#368212 Definitive Macro for Canon?

Posted by bvanant on 12 December 2015 - 02:48 PM

There supposedly is a new Kenko Tele-Plus converter for the EF-s lenses so the Canon might work, but i have not been able to find one to buy.

Bill




#368158 OMD EM-1 in Nauticam housing with Nauty Viewfinder - viewing pics though LCD...

Posted by bvanant on 10 December 2015 - 06:30 PM

You can turn off the proximity sensor.

BVA
 




#368157 Definitive Macro for Canon?

Posted by bvanant on 10 December 2015 - 06:29 PM

For me the definitive macro setup is the Tamron 60 + a 1.4 teleconverter. Great versatility, more magnification out of the box for little things and great results with external diopters.

Bill




#366409 A6000 >> Macro >> has anyone succeeded using the canon 60mm m...

Posted by bvanant on 23 October 2015 - 10:43 AM

I have shot with the canon 60 and adapter. What I do is set the focus long before shooting; and use the manual move the camera forward and back to get the shot.  Works fine if a bit slow.  Trying to use autofocus with any of these adapters (so far) seems hopeless.

Bill




#366192 Metabones Smartadapter IV with Sigma 15mm

Posted by bvanant on 15 October 2015 - 11:30 AM

It works (kind of) but in my hands at least it is terribly slow.

Bill




#365400 What is the purpose of a Dome?

Posted by bvanant on 19 September 2015 - 09:08 AM

I think we are talking apples and elephants here. I thought the OP was asking about a dome port, not a dome diffuser for a strobe. Bill




#365299 Using a UV fill light added to strobes for stills (i-Torch Pro6+) (?)

Posted by bvanant on 16 September 2015 - 03:29 PM

You will need both. The bits that I use regularly are from NightSea and FireDiveGear. Both companies make great stuff.

Bill




#365298 What is the purpose of a Dome?

Posted by bvanant on 16 September 2015 - 03:25 PM

Dome ports allow you to shoot wide angle photographs more easily. You can use them with any lens but in general you want them for wider lenses both rectilinear ones and fisheyes. The dome is acting as a big optical element and it allows you to shoot a wide scene but of a "virtual image" that is created by the dome. The virtual image is between 1 and 15 inches from the dome (depending on the dome size, larger domes lead to virtual images further away). 

http://scubageek.com...es/wwwdome.htmlis a great tutorial on domes. 

Bill