daveinwilton

<p>As an aging Xray technologist, I remember some facilities that used Polaroid xray film in the operating rooms. A big advantage in development times to the operating surgeon. Today everything is near instantaneous, but wet tanking operative films in the day, was the height of stress for all.</p>

<p>A glossy ibis working on a lobster lunch. Taken earlier this year, at Cosumnes River Conservancy.</p><div></div>

<p>Fall has reached the Sierra Nevada. The aspens have caught fire in their crimson and golds. </p><div></div>

<p>Just a little something, as I do not visit often enough.</p><div></div>

<p>Landrum, I second David Schoen, I believe you can not do better than the Sigma 150 - 600mm Contemporary for hand held birding, particularly birds-in-flight.</p><div></div>

<p>Thank you David and Adrian.</p>

<p>The cloud leopard was making his feelings known...</p><div></div>

<p>Then over to the Lion enclosure.</p><div></div>

<p>My family took me to the local zoo for my birthday. My favorite stop, the orangutans.</p>

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<p>Perhaps not the finest capture for me, but I am sure the Heron enjoyed his captured "Lobster" breakfast. Acquired at the Cosumnes River Preserve, Galt, California.</p>

<p>Canon EOS 7DII & Sigma 150-600mm F5-6.3 DG OS HSM / Contemporary @ 600mm. Technicals = 1/2500 sec; f/10; ISO 800. With a severe crop!</p><div></div>

<p>The Great Egret standing tall at the edge of a newly tilled field.</p><div></div>

<p>Who am I to argue with Canon, but I have been using lithium batteries manufactured by the drum playing rodent for about two years now without a problem in my 580II.<br>

<br /> -Dave</p>

<p>Rob,</p>

<p>I find your, and a lot of others, definition to be far too limiting. Besides, there is historical proof of single exposure HDR dating back to the mid 1950's:</p>

<p><em>Film capable of directly recording high-dynamic-range images was developed by <a title="Charles Wyckoff" href="http://en.wikipedia.org/wiki/Charles_Wyckoff">Charles Wyckoff</a> and <a title="EG&G" href="http://en.wikipedia.org/wiki/EG%26G">EG&G</a> "in the course of a contract with the Department of the Air Force".<sup id="cite_ref-23"><a href="http://en.wikipedia.org/wiki/High-dynamic-range_imaging#cite_note-23">[23]</a></sup> This XR film had three <a title="Photographic emulsion" href="http://en.wikipedia.org/wiki/Photographic_emulsion">emulsion</a> layers, an upper layer having an <a title="Film speed" href="http://en.wikipedia.org/wiki/Film_speed#ASA">ASA</a> speed rating of 400, a middle layer with an intermediate rating, and a lower layer with an ASA rating of 0.004. The film was processed in a manner similar to <a title="Color photography" href="http://en.wikipedia.org/wiki/Color_photography#.22Modern.22_color_film">color films</a>, and each layer produced a different color.<sup id="cite_ref-24"><a href="http://en.wikipedia.org/wiki/High-dynamic-range_imaging#cite_note-24">[24]</a></sup> The dynamic range of this extended range film has been estimated as 1:10⁸.<sup id="cite_ref-25"><a href="http://en.wikipedia.org/wiki/High-dynamic-range_imaging#cite_note-25">[25]</a></sup> It has been used to photograph nuclear explosions,<sup id="cite_ref-26"><a href="http://en.wikipedia.org/wiki/High-dynamic-range_imaging#cite_note-26">[26]</a></sup> for astronomical photography,<sup id="cite_ref-27"><a href="http://en.wikipedia.org/wiki/High-dynamic-range_imaging#cite_note-27">[27]</a></sup> for spectrographic research,<sup id="cite_ref-28"><a href="http://en.wikipedia.org/wiki/High-dynamic-range_imaging#cite_note-28">[28]</a></sup> and for medical imaging.<sup id="cite_ref-29"><a href="http://en.wikipedia.org/wiki/High-dynamic-range_imaging#cite_note-29">[29]</a></sup> Wyckoff's detailed pictures of nuclear explosions appeared on the cover of <a title="Life magazine" href="http://en.wikipedia.org/wiki/Life_magazine">Life</a></em><em> magazine in the mid-1950s.</em> -<strong> <em>http://en.wikipedia.org/wiki/High-dynamic-range_imaging</em></strong><br /> <br /> Certainly, a single digital exposure parallels this type of sourcing in kind. I believe that the supposed multiple exposure requirements often held onto, are nothing more than a vestigial belief held over from when RAW digital data was not available to most photographers for use in post processing.<br /> <br /> -Dave</p>

<p>Ron,<br>

I have had my best results with five image groups bracketed at 1.5 EV spacing in Photomatrix Pro 4.2. I do not use exposure bracketing, but instead shoot RAW, post processing the EV spacing. I found too much difficulty with image motion artifacts doing bracketing.<br>

-Dave</p><div></div>

<p>Back in the "Stone Age", I used to purchase disposable film cameras just for these types of uses. All waterproof housings have an indefinite life expectancy, and their seals are reliant on all sorts of variables. Just one stray piece of hair trans versing an O-ring will cause travesty at 30 feet.</p>

<p>Personally, I would suggest renting an underwater camera (like the PowerShot D30) from a reputable company: Lensrentals.com, Calumet, or the like. Spend the extra couple of dollars for the insurance, and enjoy your vacation nearly worry free. Most the p&s underwater cameras are rated for 66-99 feet, well within most of the snorkeling and scuba diving parameters of the Bahamas.</p>

<p>Best regards...<br>

-Dave</p>

<p>1+ Stephen Lewis. Bring camera out of warm shelter for a shot or two, then back into the warmth. True winterizing can be quite expensive.<br>

Best Regards...<br>

-Dave</p>

<p>Everyone here seems to be sharing the same tune, and I will jump on board...</p>

<p>At 18, I too wanted to be a photographer, but discovered that one really needs a funded "real job" to make ends meet. So I went into medical imaging; X-ray, CAT scan and M.R.I. The healthcare field keeps a roof over my families' heads and food in our stomachs. I shoot on the weekends, and during vacations. I have built up a bit of a client base over 30 years, but still not enough to fly without the net. </p>

<p>So, I concur, stay with your studies and work into the photography field in your "spare" time. I would also advise, do not burn bridges, and always keep any licensures in effect. Life always keeps happening, and you never know when lightning will strike (for good or bad).</p>

<p>The Mendocino County coast, near Westport, California.</p><div></div>

<p>And gaze out on the limitless horizon of our future.<br>

Happy 2015 everyone!</p><div></div>

<p>We reflect upon the wonders we have seen,</p><div></div>

<p>After a long absence from this forum...<br>

As the sun sets upon the year 2014,</p><div></div>

<p>Spring is coming to the High Sierras. Secondary to the relatively warm, dry winter we have had on the west coast, I thought I would take the trip up and check on Hope Valley. Not surprisingly, I was early. But I did find a consolation prize at Silver Lake along the Carson Trail on the way home. Even better viewed at 1500px size (<a href="http://d6d2h4gfvy8t8.cloudfront.net/17735080-lg.jpg">here</a>).</p><div></div>

<p>. </p><div></div>

<p>A bit on table-top work.</p><div></div>

<p><strong>Artist:</strong> David Lee Anderson;<br /><strong>Exposure Date:</strong> 2014:03:18 15:27:45;<br /><strong>Image Description:</strong> An old truck left to rust away... Perhaps in retirement, after many faithful years of service. May she find solace under the shade of the mighty oak, while her fenders are gently caressed by the wind blown grassy field.;<br /><strong>Copyright:</strong> David Lee Anderson / www.DLAndersonPhotography.com / All Rights Reserved;<br /><strong>Make:</strong> Canon;<br /><strong>Model:</strong> Canon EOS 6D;<br /><strong>Exposure Time:</strong> 1/640.0 seconds s;<br /><strong>F Number:</strong> f/2.8;<br /><strong>ISO Speed Ratings:</strong> ISO 100;<br /><strong>Exposure Program:</strong> Other;<br /><strong>Metering Mode:</strong> Other;<br /><strong>Flash:</strong> Flash did not fire, compulsory flash mode;<br /><strong>Focal Length:</strong> 70.0 mm mm;<br /><strong>Software:</strong> Adobe Photoshop CC (Windows);</p>

<p>A larger image can be seen <a href="http://d6d2h4gfvy8t8.cloudfront.net/17713480-lg.jpg">here</a></p><div></div>