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tdpriest

Member Since 22 May 2005
Offline Last Active Yesterday, 02:38 PM
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#343668 Wet Macro Lens Comparison

Posted by tdpriest on 22 February 2014 - 04:36 AM

The Fit diopters are of intermediate strength and easy to use...

 

... just to add more to the mix!

 

Fit +8D (equivalent to Subsee +5D) with step-up adaptor:

 

Fit +8.jpeg

 

Pygmy seahorse, Lembeh Strait, 105mm + 1.5x T/C + Fit pro +8D

 

2013 Lembeh 43 682 Nudi Retreat 1 Hippocampus bargibanti Pygmy seahorse.jpg

 

I like the combination of a teleconverter and the option of greater magnification with the wet diopter. I think it's a good idea to set up for supermacro and not to switch between 1:1 and supermacro on the same dive, although the macro lens and the +8D don't change the setup and mindset too much. I do believe in planning the shot and diving the plan, if possible. My planned shots are definitely better than my opportunistic efforts...

 

... I really wouldn't start with a +10D Subsee: it's too big a step, too different a technique and the learning curve is very steep.




#342835 New website

Posted by tdpriest on 04 February 2014 - 08:37 AM

Less is more!

 

I would think hard about using a really strong image on the home page, moving your biog to the inside and also putting the galleries inside except for, perhaps, a small (20-30 images) portfolio that sells your style to the browsing public.

 

I like Rob Bailey's gallery, but perhaps I shouldn't talk because I've never put my own images into order...




#342495 Whale Shark Slaughter

Posted by tdpriest on 28 January 2014 - 08:19 AM

They are clearly taking juveniles, too. Cutting the whale sharks' throats to spite their own, destroying the giants to satisfy a very short-term greed.

 

Horrible.

 

Even as a tourist spectacle, whale sharks are magnificent:

 

2013 Maldives 247 Dhidhdoo whale shark and crowds.jpg




#341411 Post processing every time?

Posted by tdpriest on 04 January 2014 - 05:03 PM

I want to achieve great photos straight from camera.

 

A great ambition, but one confined to transparencies in the days of film. Darkrooms have been part of photography for most of its existence, and are fundamental to photography as art. I learned how to shoot by working in a darkroom, by seeing what worked in the negative.

 

Morten is right in two ways: the better the image in the camera, the better it will be when projected, printed or seen on the screen; he's also right  to say that learning to make those excellent images requires a lot of practice.

 

I would point out that some of that practice can be in front of your computer.

 

 

A parting thought:

 

:evilgrin: Is ur-theory like a photograph in Plato's cave? :evilgrin2:




#341369 Testing ttl strobe accuracy on a film camera?

Posted by tdpriest on 03 January 2014 - 08:15 AM

The YS-D1 with a Nikonos sync cable certainly does ttl with a Nikonos, this should work with the F100 as well...

 

I'm surprised: this isn't noted on the Sea & Sea website. It would mean being able to switch between different circuits on the strobe: how do you do that? 




#341093 New to Underwater Photography

Posted by tdpriest on 26 December 2013 - 05:52 AM

What camera and lens(es) are you using? The exposures and focus look good, but the composition and framing are a bit off.




#341046 Your Favourite/Best Image of 2013

Posted by tdpriest on 24 December 2013 - 05:20 AM

 

 

 

Hello all! :uwphotog:

 

These are two of the pics I liked from this year. Both taken in the Canary Islands during the spanish CMAS championship:

 

Enjoy the holidays!!! :beer:  :beer:  :beer:

 

Both great, but the turtle is gorgeous, too!




#340928 Your Favourite/Best Image of 2013

Posted by tdpriest on 20 December 2013 - 04:08 PM

11436568234_df0c984b10_b.jpg

 

He looks miserable to me…  :diablo:




#340924 Stitching images

Posted by tdpriest on 20 December 2013 - 03:54 PM

I used to use Hugin, but I've been very happy with CS6 and now use that all the time:

 

 

2013 Shetland 027 126 Dore Holm panorama 02b.jpg

 

Dore Holm, Shetland (300mm + 2x T/C, tripod)

 

 

2013 Lembeh 16 992 Lembeh Resort panorama.jpg

 

Lembeh Resort (35mm, hand-held)

 

 

BSoUP Spash-in panorama Rame Head 02.jpg

 

Plymouth Sound (15mm + x1.5 T/C, hand-held)

 

 

I've noticed that D800 files stitch much more reliably than D300 files.




#340661 Your Favourite/Best Image of 2013

Posted by tdpriest on 15 December 2013 - 06:56 AM

I shall have to cheat in style, and offer one from each of my big trips; first, though, an image combining land, air and sea:

 

2013 Shetland 086 480 Sumburgh puffin.jpg

 

 

Then, from the Bahamas:

 

2013 Bahamas 59 544 Tiger Beach Lemon shark b.jpg

 

 

From Shetland:

 

2013 Shetland 107 345 Bressay wall nudibranch.jpg

 

 

From Lembeh (and not even a macro image):

 

2013 Lembeh 64 731 Nudi Falls Giant frogfish.jpg

 

 

And from Ari Atoll in the Maldives:

 

_WET7749.jpg

 

 

Oh, OK: a macro-ish image from Lembeh:

 

2013 Lembeh 61 131 Aer Prang 1 Hairy striated frogfish.jpg




#339802 Sigma 17-70mm + dome port or Canon 60mm + flat port????

Posted by tdpriest on 23 November 2013 - 04:43 AM

Your lens is probably too wide for most of Lembeh's creatures and your dome too big for close-focus wide-angle on most of the larger "macro" life. Look at the workshop thread. I hope to post my final selection of images soon, from an FX sensor and mostly shot with a 105mm lens, but some with a teleconverter and diopters...

 




#339740 Dive Destination while recuperating from shoulder surgery

Posted by tdpriest on 21 November 2013 - 08:25 AM



I had a cervical fusion last year...
...a supraspinatus repair is quite common...

 
Well, not to rain on your parade, but as specialist in chronic pain I see a fair number of repairs that remain painful, and a fair number of supraspinatus injuries that do well with physiotherapy and pain-killers. Rehabilitation with good physiotherapy and good perioperative analgesia could easily be as important as your surgeon in preventing long-term and intractable shoulder pain.
 
I've noticed that there's a tendency to treat musculoskeletal pain with analgesics and injections on the East coast of the USA, with surgery in the Midwest, and with psychology and exercise in California!

Repeated surgery for pain in the same or related areas of the body rapidly becomes ineffective, as the functional disturbance contributes more to the continued pain than the anatomical damage.


#339697 Dive Destination while recuperating from shoulder surgery

Posted by tdpriest on 19 November 2013 - 04:41 PM

I'm currently diving with an unhealed right collar bone. Its uncomfortable, but not enough to stop me...

 

I'm sorry to hear it. I suspect it's rather worse than diving with a broken rib, and that wasn't too much fun.




#337903 Strobe "Shutter speed"

Posted by tdpriest on 08 October 2013 - 07:39 AM

I couldn't find any info for Ikelite strobes so I emailed them explaining the above and they said that the cause was in fact due to the flash duration.  I asked them about DS160's given they are more powerful and they said the full power flash duration on a DS160 was longer than a DS125.

 

At this stage I just let it go as I was out of my depth.  It would be really interesting to hear from someone with technical expertise in this area and see hard data for different strobes at different power levels.  Maybe I'm completely off track with this and maybe it has no practical application in the underwater world but I would be curious to know - particularly if the make of strobe influences ability to achieve sync speed.

 

Cheers

 

There was concern about colour film being incorrectly exposed at very fast and very slow shutter speeds (reciprocity failure). As far as I know this isn't a problem with electronic sensors, and the duration of a strobe's flash has little impact on underwater photography. Sync speed depends on the camera, not the strobe, and is highest in cameras with an "electronic" shutter (ie data from the sensor is registered rapidly and not integrated over the time that a mechanical shutter allows light to fall onto the sensor):

 

http://electronics.h...utter-speed.htm




#337901 Strobe "Shutter speed"

Posted by tdpriest on 08 October 2013 - 07:26 AM

... you seem to contradict each other as a strobe "lit" duration of 1/1000 puts it within the shutter speed range? Am I right in thinking my fastest shutter is 1/8000? How do the "lit" durations vary with light emitted strength?

 

Strobe power is determined by the duration of the flash, except at very low power when the colour of the flash can also change. I can't find the specifications for a Subtronic strobe, but a typical flash's duration is indeed about 500 microseconds to 1millisecond. It takes a typical camera's shutter about 1/200 second to open and close, so faster shutter speeds (where both shutter curtains are moving at the same time) are incompatible with flash photography, as only a band is illuminated. In practice the only things that you can't freeze with a strobe in underwater photography are the strike of a mantis shrimp and the snap of a hungry frogfish's jaws...

 

... you need studio lights and a fast shutter speed or highly specialised and expensive strobe lighting to freeze a hummingbird's wings!