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jeff_conrad

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  1. If by your “sun surveyor,” you mean the Sun Surveyor app, you have many ways to get the Moon’s position vs. time. Dragging the time slider with the Moon in the info panel will adjust the values, and if desired you can show the path on the display (most useful with the map). The videos do a pretty good job of showing how to do this. You can also use the “augmented reality” feature, but you need to be on site—preferably before it gets so dark that you can’t see anything.
  2. In Clearwater on Dec. 2, the Moon’s altitude was about 10° at 6 PM and about 16.3° at 6:30 PM. These seem mighty high; are these indeed the correct times? In any event, tonight the Moon will be at 10° at about 6:55 PM and at 16.2° at about 7:25 PM. At 6:55, the Moon’s path will make an angle of about 64° with the horizon, and at 7:25, the angle will be about 65°—essentially the same. You can get the path angle from the Sun/Moon Calculator. At 80 and 110 minutes after sunset, it’s going be very, very dark—I estimate almost a 24-step difference between the Moon and the sky. So aside from your lights, it will indeed be a silhouette. I estimate the Moon’s luminance at about EV 13.7 for ISO 100; this is of course a mid-tone placement; I’d probably give a step or two additional exposure.
  3. The “Moon illusion” doesn’t work in a photograph. But you’re right that a long lens and large subject distance will make the Moon large in comparison with the subject. The Moon’s angular diameter will be about 0.56°; with a 400 mm lens and a 1.7× converter (is there such a thing?), the diagonal FoV with a 1.5 crop camera will be about 2.4°. Changing subject distance will change the size of the subject but will have no effect on the size of the Moon. I’d set the distance to make your subject the desired size; the Moon will be as it will be. If 300 ft (or whatever) isn’t enough, you’ll need to crop the image. You didn’t say where you will be shooting, so it’s tough to give you specifics. In San Francisco, the Moon will rise about 51 minutes later tomorrow night; at 36 minutes after sunset, it’s going to be mighty dark, so the foreground lighting will be provided almost entirely by your lights (perhaps that’s what you want). You can get better information from any of a number of mobile apps, including The Photographer’s Ephemeris, PlanIt! for Photographers (Pro version), and PhotoPills. If you want to work on a computer, there is The Photographer’s Ephemeris web app and the Sun/Moon Calculator.
  4. <p>The original version actually has one advantage: the DoF scale is larger and more usable. Of course, this may not matter on a 24 mm lens unless you’re doing extreme near/far.</p> <p>One caveat, though: when the lens is tilted, the marked distances don’t mean anything, so you need to determine focus points visually. And you need to remember that “near” and “far” are angular rather than linear distances. But it’s easy enough once you’ve done it a few times.</p> <p>I have the original. It’s not perfect, but it’s pretty good nonetheless. I’ve never used the Mk II, so I can’t give you a comparison.</p>
  5. <p>Roy, these values seem reasonable. They’re slightly different from mine because I already have Version 1.3 installed, but they follow the same pattern. I suspect that these entries aren’t the problem, however.</p> <p>The README for Version 1.3 calls for uninstalling the existing version before proceeding with the installation, and then inserting the CD, cancelling the installation if Autoplay is enabled, and then running the 1.3 installer to complete the installation. It doesn’t call for removing the CD until the process is complete; I have no idea how often the installation process checks for the CD.</p> <p>One way to find out what the installer is looking for is to install the Sysinternals suite (if you don’t already have it)<br> <a href="https://technet.microsoft.com/en-US/sysinternals">https://technet.microsoft.com/en-US/sysinternals</a>:</p> <p>and run Process Monitor during the installation; if you capture file, registry, and process events, you may be able to see what the installer is looking for. It may take a few tries to see how to set the filter so that you don’t need to visually scan thousands of events.</p> <p>It may turn out that you simply need to have the CD, which is what the README suggests and what I recall.</p>
  6. <blockquote> <p>However, on trying to install the 1.3 version of the software, I am asked for the disk.</p> </blockquote> <p>As I recall, I was similarly prompted, though I had not previously created the EOS Link registry entries.</p> <p>Seems to me that Canon should provide a workaround for this—it’s hardly going to cut into their EOS Link sales ... Unfortunately, as several posters to this thread have noted, the typical response from all too many companies is “Screw you, Mr. Customer.”</p>
  7. <p>Interesting; let us know how it works out.</p>
  8. <p>Roy, as I recall, you can’t—but it’s been quite a number of years since I installed the software.</p>
  9. <blockquote> <p>I contacted a friend of mine who is an LAPD beat cop and she confirmed my hunch</p> </blockquote> <p>Marc, you get your legal advice from the police? Thank goodness Nee, Moore and Quentin had better sense.</p> <blockquote> <p>It was determined that the officer acted within LAPD protocol</p> </blockquote> <p>They investigated themselves and found no wrongdoing ... um, no comment.</p> <p>The telephone tip probably gave Sgt. Parker reasonable suspicion to detain Ms. Watts; he did so and determined that no crime had occurred. Even had a crime been committed, however, there is nothing Sgt. Parker could have done because the offense (a misdemeanor) was not committed in his presence.</p> <p>Sgt. Parker’s assertion that he had a “right to ID” Ms. Watts—and your friend’s apparent concurrence—is simply misinformed, and I challenge you to cite any <em>authoritative</em> source to the contrary; I can cite many to support my assertion.</p>
  10. <blockquote> <p>In Canada that used to be called 'justifiable cause'. That is a phrase I haven't heard for many years</p> </blockquote> <p>Gup, that sounds the same as “reasonable suspicion” in the US, and it’s as applicable today as it was in <em>Terry v. Ohio</em> in 1968.</p> <blockquote> <p>Just wish chief justices would be more specific in their wording of a righteous ruling or POV</p> </blockquote> <p>Tim, in this case, they couldn’t really be much more specific—the courts interpret the laws, but they don’t make them. And <em>Duran</em> was less about grounds for a stop than about protected speech. It seems that Mr. Duran got pickled and ejected from a bar by police. On the way home, Mr. Duran apparently shouted obscenities at the officer while extending the middle finger, causing the officer to <em>fear for his life</em>. Proceeding from <em>City of Houston v. Hill</em> (1987), <em>Duran</em> held that the obscenities and finger were speech protected by the First Amendment (though I wouldn’t suggest trying either at home).</p> <blockquote> <p><strong>an imminent danger to persons or property</strong></p> </blockquote> <p>Absent violation of a law, this would be a mighty shaky justification for a stop. Of course, most things that would pose such a danger are probably illegal anyway.</p> <blockquote> <p>If the police ask me for my ID, they get my ACLU membership card.</p> </blockquote> <p>Lannie, you’re a braver man than I (and I’ve been a card-carrying member for over 30 years). My guess is that police—especially ones making illegal stops—would not be amused by such an approach, even though it’s probably perfectly legal.</p> <p>How you’re required to respond depends on where you live. In <em>Hiibel v. Sixth Judical District Court of Nevada</em> (2004), the Supreme Court upheld a Nevada law requiring a person detained on reasonable suspicion to “identify himself” to a peace officer; apparently the Nevada Supreme Court and the US Supreme Court interpreted this to mean simply giving one’s name [Tim—here’s a case where the Nevada Supreme Court definitely could have been more clear]. Although only the Nevada law was specifically upheld, it has been generally assumed that similar laws in other states that have them are also valid. It’s not that simple however, because the meaning of a state law is determined by the state’s highest court, so conceivably, laws in different states with identical wording could have different meanings.</p> <p>In California, I’m not aware of any completely dispositive ruling that says a detainee other than the driver of a vehicle need not identify himself. But California statutory law; US, Ninth Circuit, and California decisional law; actions of the Legislature; and recommendations of the California Attorney General’s office strongly suggest that a detainee need not identify himself.</p> <p>None of this may matter to police, of course. Recall the detention of actress Danielle Watts by an LAPD officer who insisted he had the right to “ID” her. He had no such right, of course, but he did have a gun and handcuffs, proving yet again that a Glock beats four aces.</p> <p>I think it’s important to remember that the ACLU deal with the LASD isn’t a new legal ruling. Detention without reasonable suspicion has always been illegal; the LASD agreement is simply that deputies will obey the law—which is not always something the LASD have been noted for. If they have also agreed that photography is expression protected by the First Amendment, it’s a stronger protection than that an activity simply isn’t illegal.</p> <p>As I said before, we’ll see what actually happens.</p>
  11. <p>What constitutes “aesthetic value”? Porn? Would the average cop recognize “aesthetic value” if it bit him? OK, perhaps I’m being a bit too harsh.</p> <p>I’m sure there are more than enough things that are prohibited without the police inventing more. But this is irrelevant; what matters is that in most cases, police lack the authority to invent more—that’s the prerogative of legislative bodies such as the Legislature and city council. And even they are constrained by the Constitution, which well might bar prohibiting photography except in the most extraordinary situations (e.g., certain military facilities). There is now a fair amount of jurisprudence suggesting that most photography is protected by the First Amendment, but I don’t think there is anything dispositive—such as a Supreme Court decision.</p> <p>Is there any such law prohibiting “suspicious” photography in LA? You can be sure that had there been such a law—valid or otherwise—it would have been cited, and there would have been no settlement. Basically, unless there is a law barring an activity, the activity isn’t illegal, and police have no authority to detain someone for engaging in that activity. And in some cases, there is a specific right—such as granted by the Constitution—to engage in the activity, which is stronger protection than the fact that an activity simply isn’t illegal.</p> <p>Alex Kozinsky—now chief judge of the Ninth Circuit—summed it up nicely in <em>Duran v. City of Douglas</em>, 904 F.2d 1372 (9th. Cir, 1990):</p> <blockquote> <p>If there is one irreducible minimum in our Fourth Amendment jurisprudence, it is that a police officer may not detain an individual simply on the basis of suspicion in the air. No matter how peculiar, abrasive, unruly or distasteful a person’s conduct may be, it cannot justify a police stop unless it suggests that some <em>specific crime </em>has been, or is about to be, committed, or that there is an imminent danger to persons or property. Were the law any different—were police free to detain and question people based only on their hunch that something may be amiss—we would hardly have a need for the hundreds of founded suspicion cases the federal courts decide every year, for we would be living in a police state where law enforcement officers, not the courts, would determine who gets stopped and when. (904 F.2d 1372, 1378; emphasis added)</p> </blockquote> <p>As we have repeatedly seen, however, what happens on the street is not always what is prescribed in the courtroom. We’ll see what happens in LA. And Ferguson.</p>
  12. <p>Bob, I have the utmost respect for Chuck Westfall. But I still don’t buy his “7/17” assertion, for several reasons.</p> <ol> <li>Again, it wasn’t stated whether this ratio applied to the object or image side of the lens. I’d probably assume the former (as you seem to do).</li> <li>A “7/17” ratio would make no sense on either the image side or the object side, except at one distance.</li> <li>Though I certainly don’t know the details of Canon’s AF system, implementing a “7/17” ratio would seem difficult on either the image side or the object side. The machinations of adjusting the image distance to achieve a “7/17” ratio on the object side are pretty involved—work the math if you don’t believe me.</li> <li>I tend to believe what I observe more than what I hear. I consistently got the same results from two different cameras introduced about eight years apart, and with several different lenses, both zoom and prime; about half were L’s. I don’t suggest that I was able to determine focusing distances to the nearest millimeter, but the tests were nonetheless designed so that I could not possibly have mistaken a “7/17” ratio for an approximate harmonic mean distance. And I repeated the tests a few months later and got essentially the same results.</li> </ol> <p>I got the distinct impression from Canon that DEP was gone and never coming back, so we’ll probably never get a definitive answer. But I measured what I measured, and what I measured makes a lot more sense than the “7/17” ratio.</p> <p>Another way to look at it: DEP actually worked much better than the “7/17” ratio would suggest.</p> <p>Getting back to Al’s original question: as ridiculous as my suggestion of using a rangefinder and calculator may seem, it’s about all I can suggest other than to just wing it. I used to think that DoF discussions that concentrated on the object side were misplaced, but I guess AF—and the demise of DEP—make them relevant once again.</p>
  13. <p>My sentiments are about the same as Ted’s—DEP (the real one) was one of the reasons I switched to Canon in the early 1990s. As Marcus notes, whatever Live View may offer, it’s far slower than DEP. And I’m not sure it’s any more accurate—unless you have all day to set focus and <em>f</em>-number.</p> <p>I never understood the alleged “7/17” focus distance (and it was never stated whether this was the object distance or the image distance). So I decided to do a few tests with an EOS-1v and an EOS-5, and determined that DEP did no such thing. Rather, it appeared to set something very close to the harmonic mean of the near and far distances, probably setting focus to the middle of the image distances—just as was done with DoF scales on manual-focus lenses. In short, the focus set by DEP was as good as I ever could do with DoF and distance scales, and it took a fraction of the time. The <em>f</em>-number was supposedly determined using a circle of confusion of 0.035 mm, but I found this a bit optimistic, and preferred to close down about a step whenever possible. The 0.035 mm criterion was a bit loose—purportedly based on enlargement to 5x7—so I’d often go down one additional step. The nice thing, though, is that the optimal focus distance is independent of the <em>f</em>-number, so the process was simple and fast. It was especially easy on the EOS-5, working much like program shift. The EOS-1v took a bit more work, changing to manual mode after letting DEP set the focus and <em>f</em>-number.</p> <p>The theory behind this isn’t rocket science, and it’s essentially what was done for years with large-format DoF calculators and DoF scales on manual-focus small-camera lenses. I discuss it in detail at <a href="http://www.largeformatphotography.info/articles/DoFinDepth.pdf">http://www.largeformatphotography.info/articles/DoFinDepth.pdf</a> (skip to Focus and Minimum <em>f</em>-Number for Given Depth of Field if you just want this topic).</p> <p>I discussed the elimination of this feature extensively with Canon USA, and they told me they were never given a reason, though they guessed—probably correctly—that few people used DEP. As Bob hints, you usually don’t care about DoF in a selfie. Most people don’t know much about DoF, and really never did. But elimination of DEP was a loss for the few who did understand it, and needed to optimize DoF in their images. Today’s multi-thousand-dollar DSLR’s cannot do what I could easily accomplish with a Pentax K-1000. Somethin’ ain’t right here ...</p> <p>I’m always amazed by people who extol the virtues of DoF calculators. No question, they give you the answers, but then how do you set the camera using a microscopic distance scale? And most of the calculators don’t address the simple question of “What focus and <em>f</em>-number do I use to get everything sharp between point A and point B?” And of course the camera’s AF is nonfunctional with this approach. DEP handled this well and did it fast.</p> <p>Conceivably, you could do the job using a laser rangefinder to measure the object distances, and then use a calculator. The <em>f</em>-number could then easily be set, but what about the distance? I guess you could scan the scene with the rangefinder until you found an object at the calculated distance, and then focus on that distance using the camera’s AF. Again, somethin’ ain’t right here ...</p>
  14. <p>Though not expressly mentioned, the thrust of this discussion seems to be photographing the full Moon when it’s fairly high above the horizon. One thing to keep in mind is that David’s third image in the linked article is a very different animal from most of the others, because the Moon is close to the horizon. When the Moon is at the horizon, it’s about 11 steps less bright than at an altitude of 40°, and it gets brighter very fast as it rises. Depending on the time of day, the Moon can go from so faint it’s barely visible to so bright that it’s difficult capture against a landscape without making at least two different exposures. Although it’s possible to estimate the brightness for a given altitude, the actual brightness is very dependent on atmospheric conditions, so the estimates are rough at best.</p> <p>Once the Moon reaches about 20°, the luminance doesn’t change so rapidly, so the exposure is much easier to estimate. And as the article David linked notes, catching the Moon well above the horizon also reduces distortion and scintillation (the latter is a big deal in most urban areas). For a full Moon above about 20°, the exposure is close to that for daylight for a realistic rendering. As Hector (and Ansel Adams) noted, the Moon is often perceived as brighter, so increasing exposure by one step may give a more pleasing rendering (Adams supposedly placed the Moon on Zone VII in his <em>Moonrise, Hernandez, New Mexico</em>).</p>
  15. <p>I completely agree that this is getting blown out of proportion. If there is a problem, it is with the regulations themselves, and quibbling about the <em>Forest Service Handbook</em> isn’t going to fix anything.</p> <p>As I mentioned, the rules that governed photography in national parks for 47 years were changed in August 2013. The former 36 CFR 5.5(b) required a permit when photography involved “articles of commerce” or “models” “for the purpose of commercial advertising.” I doubt they cared much about commercial intent, but rather wanted to control large-scale, potentially disruptive activities. The FS had essentially the same rules covered by policy in the <em>Forest Service Manual</em>; the BLM had the same policy as the FS, covered a published policy. The new rules, the result of finally implementing Public Law 106-206, dropped the “for the purpose of commercial advertising” qualifier. A big deal? Hard to say; because “models or props” was take from one of several NPS publications, a legal analysis would undoubtedly reveal that the meaning of these terms in Pub. L. 106-206 could not have been different than similar words in 36 CFR 5.5(b).</p> <p>A legal analysis doesn’t always work with People with Guns. Unfortunately, the FS <em>did</em> define these terms in the FSH at 2709.11, Chapter 45. And the BLM, FWS, and NPS provided similar definitions in the new regulations at 43 CFR Part 5 last year. Suffice it to say that the definitions are novel. For the most part, they’re just weird, ultimately causing little harm. But the definition of “sets and props” in 43 CFR Part 5 states “The use of a camera on a tripod, without the use of any other equipment, is not considered a prop.” Grammatical problems aside, this could imply than <em>anything</em> other than camera and tripod is a prop. Anyone here ever use a flash? A handheld meter? A collapsible reflector or diffuser? A second tripod? A monopod? A laptop? A camera bag?</p> <p>Ridiculous? Perhaps. But I once met BLM ranger who told me the one positive indication of “commercial photography” was a handheld meter ... And the fee schedule proposed when the DOI rule was issued last August distinguished between “camera and tripod only” and “more than a camera and tripod.” Ever since Pub. L. 106-206 was signed by President Clinton in May 2000, the NPS have assured me that nothing will really change. Perhaps that will be the case; so far, I’ve not heard of any serious hassles for using “more than a camera and tripod.” I hope it remains that way.</p> <p>The regulations nonetheless read as they read, and I am always concerned when a reassuring stated intent is in conflict with statute, regulation, or formal written policy. If nothing else, it provides an opening for the very small fraction of field staff whose raison d’être is the exercise of petty authority. Hassles are probably a very small fraction of ranger–photographer interactions, but they nonetheless occur. There have been more than a few reports of photographers getting hassled for “commercial photography” when that never was a lawful criterion. Seems to me the last thing we need is an invitation to harass for a similar technicality.</p> <p>Again, I think the panic about the proposed FS rule is essentially much ado about nothing. If there are problems, they lie elsewhere, and focusing on this serves only to distract.</p>
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