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<blockquote> <p>Surprised you didn't see it in the viewfinder.</p> </blockquote> <p>Flares are often not obvious in the OVF. A digital display shows them better, but it may not be most useful in bright light either.</p>

<blockquote> <p>Sem, if it's fast or not depends only on the skill of the photographer. If you only shoot manual and use the spot meter all the time you become pretty fast eventually. And you only need to change the exposure when the light changes. The automatic modes are prone to change the exposure every time the subject reflectance changes. Of course, if you're just learning and need to think which way to spin the dials or which way the exposure meter goes for brighter or darker then using the spot meter becomes a very slow process.</p> </blockquote> <p>If one is shooting landscapes, spot metering is surely viable. But for certain sports or when chasing kids, it makes no sense, with the microprocessors in current cameras. I mean, I don't think my exposure routine is something particularly creative or something that couldn't be handled by a computer; it is just that the current meters don't do what I want.</p> <blockquote> <p>It's interesting what you write about the in-camera processing restrictions. As you say there might be restrictions based on pure processing power requirement or even memory requirements. It's of course impossible for us to know and it might explain some odd behavior.</p> </blockquote> <p>Well, yes, we see all sorts of computing restrictions in gadgets. Mainly because, due to economy and power consumption, the processors are barely capable enough to do what they are supposed to do. I guess some of the restrictions may as well be due to using limited precision (bit-length) in arithmetics, possibly fixed-point, which may be seen as a limitation of the dynamic range, etc.</p>

<p>Joe, </p> <blockquote> <p>Sounds good to me. It would be foolish to use up all the RAW headroom by effectively overexposing by 1 - 1.5 stops. Not many users need a 12 stop dynamic range for their everyday shots, but they <em>do</em> need a metering mode that doesn't blow highlights irrevocably.</p> </blockquote> <p>I think it is fair to have a HWM mode for JPG shooters, but it would be even better to have an additional one for raw shooters that wouldn't waste highlights headroom. <br> Pete, </p> <blockquote> <p> <strong>So one stop headroom for all practical purposes. ...</strong></p> </blockquote> <p>I'd agree that one stop is a likely result. But it may be different with some PCs like Vivid and in extreme WB conditions, with ADL... <br> I think an auto-raw-ETTR option would be welcome for many, because I think this is something useful and relatively straightforward for automatic implementation. I'm not saying that it is trivial, because it appears that it would require a certain degree of reengineering of Nikon's metering implementation.<br> I agree that small specular highlights are a problem here, because they make the right edge of the histogram ill-defined. With the OVF, the number of metering points is restricted, so one might still get blown pixels. This would appear not to be a problem in Live View where metering is done using the main sensor; however I assume only a subset of pixels or a half-processed image is used for metering for the sake of speed. But this should be considered by reasonable thresholding. (Further you get questions what to do with the sun and stage-lights in the frame...)<br> Of course, the spot meter is one alternative, but not a fast one. </p> <blockquote> <p>I wonder if this Nikon's answer to Canon's highlight tone priority mode.</p> </blockquote> <p>AFAIK HTP is a variant of ADL, DRO, ALO, etc, which underexposes the raw data by a small amount (compared to the default midtones-centric meter) like all the rest, then applies instant processing which emphasises the highlights range rather than lifts the shadows like most of the rest. I think this is mainly a rendering decision. In "harsh light", the scene DR is essentially wider than what the output DR (prints and current displays) can show. Therefore, tonemapping which involves substantial DR compression is used. Typically one can make both highlight and shadow details better visible at once, but contrast is killed along the way... there are compromises involved, and the computer doesn't know what is deemed important in the image. A capable raw converter (and PS further on) has several sliders avalilable to bring out the desired result which may be very different. ADL only has one manual "intensity" adjustment (there is more done under the hood). HTP offers a different approach which doesn't compress the highlights as much. <br> It is not clear to me why all these instant DR "enhancements" underexpose, except ADL used with the HWM recently, tend to underexpose raw data - in the sense that when the resulting JPG histogram looks right, the raw histogram tends to show two or more stops unused highlights headroom. Meaning that a substantial amount of the sensor DR gets wasted, and with earlier Nikons there was an obvious penalty in the noisy shadows. I suspect the underexposure was made to make room in the highlights for the instant processing - notice that the fill-light ("shadows protection" in NX) operation causes just about as much lift in the highlights as ADL underexposes the raw data. The unlogical bit is that the in-camera raw conversion in the D90 already has an exposure compensation parameter which should do the trick without a noise penalty. Unless there are other processing restrictions...</p>

<p>I guess the OP wants a quality variable-length helical extension tube, which may indeed be a difficult-to-find item. I've seen a new product like this (a bit longer, and with electronic contacts) for sale a couple of years ago, but the reviews were dismal on account of poor mechanical quality. <br> I recall some were using the Vivitar without the glass; though I've got no idea how difficult the surgery is, and if there happens to be vignetting with certain lenses (as with some other narrow-holed tubes used on FX). <br> Similar TCs used to be sold by Panagor. </p>

<blockquote> <p>The highlight metering mode is a special type of spot metering:</p> </blockquote> <p>As much as I understand it is actually a variant of the matrix meter. But unlike the usual MM it finds the brightest highlights and exposes so that they're not blown (in wide-DR scenes, the MM goes for the midtones, with some bias for what's under the active AF points, mostly resulting in brighter images and blown highlights).<br> I haven't tried it myself, but a number of exposure-sensitive people say that it doesn't do what they'd like it to do most, that is automatic ETTR for raw images - that the resulting raw files are often exposed lower than to the right edge of the raw histogram (RawDigger etc). I guess it is probably made for use with JPGs. </p>

<p>I guess such an issue would be more likely due to the camera profile used when importing images (selected or default)... that should certainly affect the default rendering & histogram. <br> On my laptop display I often see radioactive colours in the highlights due to its limited gamut, while the LR histogram doesn't show any blown highlights. </p>

<p>As I drag the LR window more than half-way to my external display or back to the laptop display, I see the image rendering change due to the switch of the monitor profile, but the histogram doesn't change. </p>

<p>Yes Nikon requires a chip in the lens for auto metering (actually, a bit newer Nikon bodies like the D90 and smaller do meter without chip, but only in live-view preview and movie mode, not for stills).<br> If you want auto metering, you can look for a "Dandelion" (Tagotech) metering chip, around $30. </p>

<p>Odd, I've been playing with the K1 & the D90 and I don't recall the angle issue. Had the 18-200VR which has a petal hood on it. Did some shaving for the lens AF contacts, and had to latch the aperture lever of the lens to open it up a bit. <br> http://www.dpreview.com/forums/thread/3034839<br> http://www.dpreview.com/forums/thread/3041926<br> I recall the K tubes are pre-AI, and there may be issues with the aperture sensing tab on the bigger bodies?</p>

<p>> My last question here is what people feel about comparison of the Nikkor 40/2.8 macro and the Nikkor 60/2.8 macro? Does the 60/2.8 offer that much more above the 40/2.8 with its increased cost? The shooting distance is 2+ inches more for the 60 but is it that much better for macro shooting and for using for portraits, too? <br> The 40/2.8 is DX only, and the working distance is even shorter. Short macros include a wider area of the background in the frame, which gets relatively less blurred, so you get an impression of more depth than there is DoF. The extreme effect of this is the macro modes of compact cameras at wide-angle; but there are no really-wide-angle 1:1 macro lenses, you can only workaround using a conventional wide-angle lens on a thin extension tube (but the achievable magnification at a still workable working distance depends on the lens). <br> With long macros, the included part of the background is small, relatively heavily blurred, and you may be able pick a clean part of it, and the working distance is more generous. But they are expensive, heavy, and the technique gets more challenging. You can workaround using a relatively weak diopter achromat on your 70-200 (Marumi +3, Canon 500D...). A thicker extension tube may work too instead of the achromat; or a 2x teleconverter. <br> For budget macro/portrait I'd recommend Tamron 90/2.8 non-VC (cheaper than the more recent VC) or 60/2 (DX) - both happen to have the working distance at 1:1 around 10 cm. </p>

<p>How does manual focus feel? Any "dead zone" or "stick-slip"?</p>

<p>The K-1 is useful for wide-angle closeups, with non-macro wide-angle lenses that don't focus close enough. No auto coupling is feasible with such short extension. AFAIK it is safe with modern cameras, but it is very tight on lens electric contacts, so I've shaved mine a bit. Some other AI-age (up to now, as they've never been electrified) Nikon extension tubes without "A" may also have issues; you should google up each one separately. <br> It is possible to stick a "Dandelion" metering chip to the BR-2A for some sort of auto metering. But mind these chips pretend to be G-type lenses but obviously don't supply the focus distance, which causes certain problems (which do not show up with AF non-D lenses also lacking the distance info). In particular, it confuses TTL-BL flash metering, so plain TTL should be used instead. </p>

<blockquote> <p>I don't see that changing the picture control settings will affect the raw file as such but since changes affect the jpeg they also affect what we see on the lcd in terms of the picture's appearance and the histogram. If we use the histogram to influence our choice of exposure, the picture control settings will surely be a factor?</p> </blockquote> <p>I think this is what is going on. Flat has lower contrast, so the histogram shows a wider dynamic range window. I guess this makes the meter more useful for raw, as the invisible "highlights headroom" shrinks. If you turn of autoWB, you get closer to the UniWB approach. And the shadows get slightly lifted too. But preview generally looks crappier.<br> I haven't checked out this new flat PC. One could edit the PC and set lower contrast before though, but the issue was that the dynamic range of the processing was narrower than the one of the sensor already on the D90. So one could get clipping on both edges of the histogram in certain limit cases where the raw data was in fact not blown by Rawnalyze. VNX would blow the same in a single conversion (but one could do multiple with different exposure slider positions and HDR blend), but LR and DxO OP were able to process this nicely.<br> I was hoping the new HWM would do Uni-WB-like auto-ETTR for raw too, but I hear from several reputable sources that this is unfortunately not the case (that it sometimes exposes lower than desired). <br> DPR claims that ADL no longer adjusts raw data exposure when used in conjunction with HWM. I'd guess this should make better looking previews while throwing the histogram less off than before (with my D90 on MM, ADL helps save the highlights sometimes if I don't have time to adjust EC for harsh light; on the other hand, one gets grossly underexposed raw data when tuning EC to ETTR using the camera's histogram).<br> There is however a rumour about an upcoming Nikon firmware update program supposedly bringing raw histograms. This is a sign of a new wind; if they see the need for raw histograms, they might see one for auto-exposure based on them, although there are a few practical issues (what to do with the sun in the frame; small specular highlights and the relatively low resolution of the exposure sensor). And eventually they could also consider how to render better previews in harsh light based on such exposure. </p>

<p>Nikon's VR has different operation modes for aiming (triggered by the half-press and probably also AF-on) and for the actual exposure. Mind the active element is re-centered just prior to the exposure, and this move is supposed to settle in the short time before the shutter opens. There is a chance that this behaviour causes some blur, especially if the system happens to get detuned somehow. </p>

<p>> Nikon D3100 10x High Definition 2 Element Close-Up (Macro) Lens (52mm)<br> First time I hear for this, and it doesn't seem to be in any relation with Nikon except trademark abuse? <br> It doesn't look thick enough for a +10 diopter two-element achromat. See this +5 Marumi http://www.amazon.co.uk/Marumi-DHG-52mm-Achromat-Lens/dp/B003DIR5DQ and +4 Canon 250D http://www.adorama.com/ICA52CU250D.html<br> The 52mm thread fits the 50mm f1.4D though.<br> See also: https://answers.yahoo.com/question/index?qid=20110502171809AAR7KrS</p>