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Basil

Member Since 02 Dec 2012
Offline Last Active Aug 24 2015 08:00 PM
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Posts I've Made

In Topic: Is TTL possible with Panasonic LX100 and Nauticam housing?

24 August 2015 - 08:00 PM

To answer the question, YES you can do TTL with a Sea & Sea strobe, and the LX100 in a Nauticam housing.

 

I screwed this up for several days, before I finally started to get it right (with the help of a more skilled photographer friend on my last dive trip).  So here is how I got nice results:

I have a single Sea & Sea YS-D1 strobe, connected to my LX100 camera flash by fiber optic cable.  I have the Nauticam housing.  The YS-01 is the previous Sea & Sea strobe model, it probably is not that different from the YS-D1.

 

I made sure to turn the pre-flash OFF on the camera (the AF assist lamp - page 3 of the custom menu (the one with the wrench and the letter C next to it)).  What I was told is that it is difficult to get strobes to work (at least with a fiber optic connection) when your camera is doing a pre-flash.  That makes sense to me, since the camera & it's flash are actually blocked by the housing, and don't actually illuminate the subject.  I also made sure the red eye removal is OFF (in page 5 of the camera menu)

 

I then I set my strobe to TTL, and my White Balance on Auto White Balance (AWB) (since you have a lot of light).  It worked really well.  Some shots were a touch overexposed, but I shot in raw, and it was very easy to dial that back a bit in post.  

 

Alternatively, you can try the strobe in manual mode, but use the single lightening bolt setting on the strobe, NOT the double lightening bolt setting (I assume the YS-01 has a similar setting to the YS-D1).  That is where I screwed up for 2 days -- I was using the double lightening bolt setting -- which means the strobe is expecting a preflash (focus light) from the camera, followed by an actual flash.  The strobes mirrors this, by sending out its own pre-flash, followed by the strobe's main big bright flash.  However, my camera was not firing a preflash at all, just firing off the main flash, but I had effectively set my strobe to only be firing a teeny tiny preflash, which just illuminates a small circle with very weak light (as opposed to a big strobe flash), and then the strobe is waiting for a 2nd pulse of light from my camera's flash, which then never comes.  The end result was that my pictures were WAY WAY underexposed, and I was...confused.  Once I figured out the strobe problem (with my friend's invaluable help) I just went with using the strobe on TTL, and it made a HUGE difference.  (It makes me want to go on another dive trip, just to play more with my strobe!)

One other thing to note -- the LX100 has a leaf shutter (several higher end compact cameras have this feature, as do medium format camera/lenses -- which cost thousands of dollars).  As best as I understand it, basically the shutter is in the lens, not on the focal plane with the sensor.  The benefit of this, is that you effectively have less of a limit on the flash synch speed you use.  Most cameras have a flash synch speed of around 1/250 or 1/320 of a second, which is a ceiling for the maximum shutter speed.  The LX100 does not have that same hard limitation because of the leaf shutter -- you can shoot up to 1/2000 or 1/4000.  The shutter speed does not determine how much light hits your subject from the strobe -- that is controlled by the camera's aperture, and more importantly, how much power you give to the strobe.  But the shutter speed does control the ambient light which is lighting the background.  There may be shots, where you are really tightly focused on your subject, and you  want the background to be a bit darker to better isolate the subject --- and so you can bump up the shutter speed from 1/250 up to 1/500, or even 1/1000 (the max you would probably use underwater).  

I hope this is useful to you (and not too confusing). 


In Topic: Sony a7s and MWB

24 August 2015 - 01:57 PM

On my Sony NEX-5R, I would set a manual WB, shooting usually at sand (that seemed to work best), although sometimes my white card would work (sand actually seemed to work better).  I would get an error message, but would just press "OK" -- basically telling the camera that the crazy WB reading was ok, and it would accept it. Additionally, I had a Magic Filter (gel) affixed on the backside of the lens.  Those 2 together seemed to get me a decent WB.


In Topic: LX100 - Underwater video shot on the Red Sea

24 August 2015 - 12:54 PM

I love the LX100. I sold my NEX-5R and housing and got this instead.  I love the camera's ergonomics (it's very old school), and I love the assurance of the vacuum pump option on the housing!

 

I used the dome port most of the time, but towards the end of the cruise, I switched to the default flat port.  The dome port give a wider field of view, but I found a little quirk -- the autofocus does not work well on the dome port, except when you are shooting wide (24-26mm) -- fortunately, I usually am shooting close focus/wide angle, so it is not a problem, just a "quirk".  I conferred with one my very expert photography friends on the dive cruise, and we decided that it must be because the "virtual image" created by the mini-dome port is pretty close to the camera, and is closer than the minimum focusing distance for the lens, except when the lens is at a short/wide focal length (the LX100's lens can focus on something within 1.5 inches, when the lens is at 24mm).  So, in theory, you can zoom in using the dome port, but then you have to manually focus, which can be difficult when you are drifting along.  When I switched to the flat port, this quirk just went away -- the autofocus performed well at all focal lengths, because the camera is focusing on the actual object, as opposed to a virtual image.  Sometimes, for fish that were extra skittish, it was nice be able to zoom in a bit to get the image, although that is less practical underwater than on land because of the limitations of lighting.

The colors are great, the lens is really fast/bright (F1.7 - 2.8) which helps offset the limitations on the ISO performance -- I tried to keep the ISO at 400 or below for most shots to keep the blue background from being too grainy.  The resolution is great -- there is plenty of details in the shadows, which can be recovered.  I did a bit of tweaking with the video clips (final cut pro), usually just boosting the color on midtones, and reducing the exposure on highlights, and that really seemed like enough to make things pop!  The custom white balance is excellent and easy to use.

I have the CMC, but truthfully, I never did much macro shooting.  I still have to learn how to use a wet lens correctly.  One step at a time -- this camera is a great tool to learn on!!


In Topic: Underwater World of Anilao

07 July 2015 - 07:39 AM

Moses,

 

This is gorgeous!  You should be very proud of your work. It's really lovely!

I have a few questions:

Correct me if I am wrong -- you don't use Magic Filters -- you rely only on manual white balance. 

 

Which "picture profile" did you use on the LX100 underwater?  Did you change the Noise Reduction, Contrast, Sharpening or other settings?  (I have been playing with those on land, but still haven't decided what works) 

Did you use one of those contrast curves (shadows/highlights)?

When you edit - do you edit the video in 4k and then export it to 2k  or HD, OR, do you edit the video on an HD or a 2K timeline? (I'm trying to figure out which one works better, still haven't decided).

 

Forgive me for peppering you with so many questions -- I was away over July 4, and while I was gone, my Nauticam housing came for my LX100.  I am so excited -- I haven't even had the chance to open up the box yet (I'll do that tonight), but I am trying to get ready for my big dive trip to the Red Sea (Egypt) at the end of the month!

Basil
 


In Topic: 4K: Current Pro- and Semi-Pro Underwater Filming Options

22 June 2015 - 07:24 AM

Ikelite does not make a housing for the Samsung NX1 -- its not on their website.  I asked them directly if they would, and they said no.