Disqus - Latest Comments for BWJones

Re: The Human Eye is So Sensitive, It Can Detect a Single Photon of Light

BWJones — Mon, 25 Jul 2016 17:57:51 -0000

This result was originally shown/published back in the 1940's... This new study claims to measure, but they are still calculating the quanta. More precise that the original study, but not new.

Re: Awesome Find: Mint Condition Zeiss Planar 1.5/50 Lens… for 10 Bucks

BWJones — Mon, 09 May 2016 15:54:10 -0000

"So I put the filter back on and told the women selling the camera that it was non functioning and would be used as a paperweight. I managed to bargain her down to $10 for the camera and lens both."

That is a jerk move...

Re: In 30 Years of Photography, I’ve Never Had a Service Experience Like This

BWJones — Mon, 11 Apr 2016 17:47:46 -0000

I am glad that you have experienced good service from Leica. Perhaps the service in Germany is better than it is in the United States?

Re: In 30 Years of Photography, I’ve Never Had a Service Experience Like This

BWJones — Mon, 11 Apr 2016 17:47:07 -0000

Then, Jason... I will not be expecting you to visit my site. The story was mine and it was placed on my blog for context and information. You may choose to interpret what you will.

Re: A Retinal Neuroscientist’s Rebuttal: Why Humans Can’t See Near Infrared, No Matter What They Eat

BWJones — Mon, 25 Aug 2014 23:44:19 -0000

Ah, sorry. I did not scroll down this far and load comments from the iPad, so I did not see this. You can see that I answered Bill's post above.

Oh, and you might want to rein in glims... I've not been put off quite that badly by an exchange in some time. It reeks of ignorance and unprofessionalism and I will not respond further to him and waste time with that.

Please do read the comments in reply to Bill above as there are some safety issues associated with exposure to IR radiation that you should know about. Also know that there have been *many* studies on the properties of opsins going back to the turn of the century and the Kolb reference in Webvision is certainly not alone. Also understand that there are many kinds of opsins in many species and lots of the studies that were performed were done on everything from cow eyes (lots of rhodopsin available in the big eye) to frog eyes (some of the first experiments in photobleaching) to mouse eyes (genetics). So, spectral response curves in the literature can vary somewhat. Also the ragged ends of the spectral response curves can always be revealed through the application of more power. But as I discussed in the response to Bill above, those are non-biological and are potentially dangerous.

Also know that many of the studies in the evolution of opsins were done by T.D. Lamb, whom you reference. By the way, Trevor Lamb is also a contributor to Webvision: http://webvision.med.utah.e... and his experience with the evolution of opsins and visual systems is unparalleled.

Re: A Retinal Neuroscientist’s Rebuttal: Why Humans Can’t See Near Infrared, No Matter What They Eat

BWJones — Mon, 25 Aug 2014 23:35:48 -0000

Hey Bill,

Thanks for that article. The answer is a little complicated, but bear with me. Yes, the early studies did push stimulation down to the near infra-red and you can get responses.

But here is the deal... You can get any molecule to excite and induce resonance. The problem is that it is not biological and it causes damage. In the UV spectrum, those energies cause vibrational energy to chemical bonds and break them. In the IR range, you cook proteins.

So, after 1947 when optics and light energy started becoming more of an interest (lasers, etc...), it was found that IR and near IR radiation is dangerous to ocular tissues. Most of the studies performed have been looking at mid and far IR, but its been found that the cornea absorbs most of the wavelengths above and beyond 1400nm to around 3000nm. The real problem with the IR-A or near infrared is the lens which absorbs IR energy from around 900nm to 1400nm. When this happens, you get cataracts. Bad ones. This has been known since at least the 1700s when people started using telescopes to look at the sun or when glassblowers in Italy started developing cataracts.

Below around 1400nm, that energy is absorbed by the retina. That means heating of the retina and heating of structures that are already operating on the edge of oxidative damage. The interface between the photoreceptors and the retinal pigment epithelium is the area of your body with the highest oxygen turn over per unit volume and its running on the ragged edge of its ability to detoxify and deal with oxidative damage.

So, if the cornea allows (its bandpass function) most of the IR radiation between 700nm and 1400nm, that radiation is passed directly to the aqueous humor and the retina. Once it reaches the retina, most of that energy is absorbed by the RPE or retinal pigment epithelia. The neural retina then is heated through conduction. The scary thing is that heating can happen in literally fractions of seconds. I did some consulting for the US military a few years ago where we discussed heating with respect to the proliferation of laser weapons on the battlefield and this is a big deal, particularly as many of the lasers and emitters are in the IR range covering near to mid IR. As I recall, the IR studies done on primates by the US Army revealed exposures from 700-1400nm took around 15 minutes to cause obvious burns which is why most optical coherence tomography devices have absolute limits on how long exams can take. However, those studies were gross clinical studies with no protein expression, metabolic or even histology that occurred, so we don't really know yet what the exposure time is for damage to visual function. Psychophysics studies were not performed on those animals to my knowledge.

Re: A Retinal Neuroscientist’s Rebuttal: Why Humans Can’t See Near Infrared, No Matter What They Eat

BWJones — Mon, 25 Aug 2014 20:58:56 -0000

I think we are done here. This is the most unprofessional exchange I've had since getting trolled on Slashdot. Please post the results of your plagiarism checker here for the record.

This is *precisely* what I wrote: "For instance, there is an excellent summary here on Webvision, the Internet’s very first online textbook:
In short, there are 4 kinds of photoreceptors in our eyes, rod photoreceptors which detect electromagnetic spectral energy from ~400nm to ~580nm with maximal sensitivity at 496nm (blue/green light), and long, middle and short wave cone photoreceptors."

That is clearly an attribution of record, not plagiarism.

Re: A Retinal Neuroscientist’s Rebuttal: Why Humans Can’t See Near Infrared, No Matter What They Eat

BWJones — Mon, 25 Aug 2014 19:18:31 -0000

Oh, you have got to be #@$&ing kidding me... Seriously?

You are referring to this paragraph: "The long wavelength sensitive, L-cones (“red cones”) are known to be maximally sensitive to wavelengths peaking around ~560nm, medium wavelength sensitive, M-cones (“green cones”) peak around ~530nm and short wavelength cones, S-cones (“blue cones”) peak at ~420nm respectively."

That is paraphrased from the Webvision chapter that I edit and is cited there deriving from (Bowmaker and Dartnell, 1980; Bowmaker et al., 1980). Its hard to accuse me of plagiarism when I cite Webvision as a source for the material in the previous paragraph.

Re: A Retinal Neuroscientist’s Rebuttal: Why Humans Can’t See Near Infrared, No Matter What They Eat

BWJones — Mon, 25 Aug 2014 19:05:55 -0000

Wald is not the author. Helga Kolb was the author of that article and nothing was plagiarized. Be careful... You are rapidly losing credibility here.

Re: A Retinal Neuroscientist’s Rebuttal: Why Humans Can’t See Near Infrared, No Matter What They Eat

BWJones — Mon, 25 Aug 2014 19:03:28 -0000

Show me please. Show me what is directly copied as opposed to summarized.

Also note that I work with Helga Kolb closely on Webvision.

Re: A Retinal Neuroscientist’s Rebuttal: Why Humans Can’t See Near Infrared, No Matter What They Eat

BWJones — Mon, 25 Aug 2014 18:35:24 -0000

Where are you claiming that this is copy and pasted from whose writing? Are you accusing me of plagiarism? Is that where this is going?

Furthermore, you are aware that I am an editor for Webvision, right?

Re: A Retinal Neuroscientist’s Rebuttal: Why Humans Can’t See Near Infrared, No Matter What They Eat

BWJones — Mon, 25 Aug 2014 16:53:51 -0000

I'll look forward to reading it.

Re: A Retinal Neuroscientist’s Rebuttal: Why Humans Can’t See Near Infrared, No Matter What They Eat

BWJones — Mon, 25 Aug 2014 16:49:02 -0000

Hey Carl,
Why don't you do some calculations on how much energy would be required to activate those bonds from IR energy sources... Go ahead, I'll wait. Never mind, I'll tell you that in essence, yeah, you can do it, but the heat energy being absorbed would start cooking the tissue.

Also, that thing where you see stars when pushing on your eyeball? Yeah, those are TRP channels. Completely different mechanism. You can also hit yourself in the back of the head and see stars. Neither one of those are vision nor are they visual processing.

Re: A Retinal Neuroscientist’s Rebuttal: Why Humans Can’t See Near Infrared, No Matter What They Eat

BWJones — Mon, 25 Aug 2014 16:37:03 -0000

You did not read what I wrote... The biophysical limitations of the long-wavelength cone is absolutely at its limit at ~650nm. Shifting that biophysical performance >50nm is simply not within the boundaries of possibility. And the curves you *DID SHOW*, indicated responses at 850nm and 950nm... Beyond credulity.

Re: Giveaway: Win a Fuji X-T1 Kit AND Battery Grip!

BWJones — Thu, 27 Feb 2014 23:24:53 -0000

I'd use the X-T1 as a true photojournalism tool, covering the commissioning of a brand new US Navy submarine in the very near future. The Fuji small size will be ideal for navigating tight quarters on board.

Re: Media Day: A Freezing Start To SHOT Show

BWJones — Tue, 15 Jan 2013 03:30:04 -0000

I suspect that the first thing homo sapiens did when acquiring language was to complain about the weather... and in particular about how cold it is. That said, after a hot shower and two hours inside the hotel room processing images from Media Day, I am still cold.

Re: Prof. Richard Crandall dead at 64

BWJones — Fri, 21 Dec 2012 08:58:42 -0000

My condolences to Richard's family and the community at Reed. I had the distinct pleasure and honor of visiting with Richard a couple of years ago in conjunction with Apple's Advanced Computational Group, and was impressed by his hospitality, candor, thoughtfulness and intellect. Thank you Richard.

Re: Eyeball the size of a softball washes up on a Florida Beach

BWJones — Fri, 12 Oct 2012 12:19:53 -0000

How could it take them that long to figure out what the eyeball came from? 6 muscle insertion points makes it from a mammal. If its a vascular retina, then its a mammal... Its probably from a fish, like a marlin as a squid iris is less round. Ship that eye up to some vision scientists... like us. :-)

Re: Firing a pistol underwater

BWJones — Sat, 29 Sep 2012 21:24:57 -0000

Cory, you are including a photo (uncredited) from my friend Andrew's (@VuurwapenBlog) site: http://vuurwapenblog.com/20...

Re: Born Standing Up, by Steve Martin

BWJones — Sun, 15 Jul 2012 17:01:21 -0000

I remember seeing Steve onstage in Kingsbury Hall opening for the Deseret String Band in Salt Lake City, Utah some time around 74 or 75... Was just a small kid, but did not understand what the whole rabbit ears and arrow through the head meant, even though the entire hall was teary eyed from laughing.

Re: Student's brain flatlined during classes

BWJones — Mon, 30 Apr 2012 13:10:17 -0000

Note: This is electro*dermal* activity, NOT brainwave activity. Honestly, the interpretations of this study are kinda silly as people are presuming this is the level of cognitive activity and its nowhere near that level of data.

Re: Blue Moon Moonrise

BWJones — Mon, 01 Aug 2011 12:48:18 -0000

Naw man, this *totally* works. I love it.

Re: Canon 5D MkII Sensor Zapped by Lasers

BWJones — Mon, 11 Jul 2011 12:19:30 -0000

And what do you think that the lasers are doing to your retina? The use of lasers have historically exploded in places like the battlefield ( http://prometheus.med.utah.... ), but the use of increasingly powerful lasers for club shows and entertainment is seriously concerning.

Re: Feathery Friendly Sunday — Sandhill Cranes

BWJones — Sun, 17 Oct 2010 22:36:07 -0000

Gorgeous animals! Every time I hear them, I think that is what at least some dinosaurs must have sounded like.

Re: Greetings from Honolulu

BWJones — Mon, 04 Oct 2010 23:50:58 -0000

Very much looking forward to your work on the JMSDF. Theirs is a mission that will be growing substantially over the next decade.