darren_cokin
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Posts posted by darren_cokin
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<p>Thanks for posting Guillaume, I'm delighted people are still finding this.</p>
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<p>Taken with 105mm f/2.0 DC, mounted on a D200. f3.5, 1/500sec, iso100. I've never used the DC feature; periodically I experiment with it, but don't see much difference honestly. But I do love this lens! I considered the getting Micro-Nikkor VR when I was shopping for a 105mm, but decided the extra stop was more important to me than VR or macro focusing.</p><div>
</div>
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<p >I've had the 105mm f2 DC for about 2 years now, and it's been one of my most used lenses since then. But I haven't used the DC feature at all! I experiment with it every now and then, when an obvious opportunity pops up, like a branch in the foreground I can't get out of the way. I'll try shooting the same picture with the DC ring in all sorts of positions, and don't really see much difference honestly.</p>
<p >When I was shopping for a 105mm, I considered the Micro-Nikkor f2.8 VR, but decided the extra stop was more important to me than VR and close focusing. Don't regret my decision at all.</p>
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<p>Another option, is to add the GPS tags after the fact. More convenient in that you don't have a cable running into your camera, less convenient because you have a little more work later, and have to remember to turn on your GPS log before you start shooting. Another plus is that you may already have GPS in your phone, so there would be nothing to buy.</p>
<p>A free multi-platform program called "Geotag" is what you would use to add the tags to the pictures, based on the time stamps. (1st thing in the morning, synchronize your camera's clock with your GPS unit's.) Use a GPS unit that can save a log of your movements. "BBTracker" is one such tool that works with Blackberry's and some Nokia phones; I'm sure there must be similar tools for iPhones, and dedicated GPS units...</p>
<p>Darren</p>
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Not sure about San Clemente, but if you're spending time in LA, you could rent an underwater housing from <A
href="http://www.absea.net/rental.html">AB Sea Photo</A>, by LAX.
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Was reading Keith Cowing's NASA Watch blog, and saw <a
href="http://www.nasawatch.com/archives/2007/08/guess_what_came.html">an
article about a recent NASA procurement request</a>. They want seventy-six
Nikon D2Xs cameras, all manufactured in the same lot. Forty-eight of these
should be manufactured with braycote grease instead of whatever lubricant they
typically use. (Braycote is commonly used in vacuum and other harsh
environments. The other 28 cameras are probably just for crew training, or
conventional photography use on the ground.) Also, sixty-four SB-800 flashes,
33 of them with braycote. twenty-seven 12-24mm f4.0 DX lenses, twelve 10.5mm DX
fisheye lenses, 225 EN-EL4A batteries, and twenty EH-6 AC adapters.<br><br>
He also shared a link to this recent photo from the space station:<br>
<a
</a><br>
I see two D200's with vertical battery grips, four flashes, at least 3 of which
are SB-28's (which is odd, because they're not fully compatible with D200), a
bag of memory cards, and two very long lenses. Anyone recognize the models?
They use those for earth observation mostly.<br><br>
Darren
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Here you are; 3 choices all set up for recharging nikon batteries:<br>
<a href="http://store.sundancesolar.com/sobachforni.html">http://store.sundancesolar.com/sobachforni.html</a>
<br><br>
Browse the rest of the website if you want something more powerful; for more than just your Nikon...<br><br>
Note, I am not recommending any of these products; I haven't used them, it's just a link I had that seemed to be what you were looking for.<br><br>
Good luck.<br><br>
Darren
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Do you need something with accurate adjustments, or do you just want to make it easier to track the quick moving moon across the sky?<br><br>
You can use any ballhead with a panning base for that, if you flip it upside down. Here's a picture of mine, with a quick-release on both sides, so it can be flipped as needed. (Upside down position also used for stitched panorama's, which need to be leveled.)<br><br>
Equipment shown is:<br>
Nikon 80-400 VR lens, with <a
href="http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00HfRR&tag=">homemade
lens scope converter</a><br>
<a href="http://www.markinsamerica.com/MA5/M10-NQS.php">Markins Q-Ball M10
ballhead, version w/o quick release</a><br>
<a
Novoflex MiniConnect Quick Release Adapters (round version)</a><br>
<a href="http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00HfRR&tag="></a>Gitzo
tripod, with <a
fender washer</a> providing base for MiniConnect <a
release plate</a><div>
</div> -
<i>The SB-50 DX is on the small side, but it does not use AA batteries. Battery is a bit of a pain.</i><br><br>
I disagree. They're not a pain anymore; rechargeable CR123's have been available for a while now. Here's one option, with a convenient dual charger:<br>
<A href="http://outpost.com/product/4426066">http://outpost.com/product/4426066</A><br><br>
Darren
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"Everyone sit still for 6 seconds... Starting... now."<div></div>
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If you have any interest in stereoscopy, this would be a great opportunity to take some 3D pictures. You just have to make sure you're pointing to the side, 90 degrees from your flight path. (Tilting up/down is okay, but don't swing forward/aft.) Set the camera for continuous shooting mode, and take 2 or more pictures in a row when you're flying over the mountains, or in sight of a downtown area. Zoom in if you have to, to keep the wing out of the frame.<br><br>
General rule of thumb is that the distance between your right and left shots should be about 1/30th the distance to your subject, for the best 3D effect. So taking into account the speed of the aircraft and the camera's frame rate per second... it's best to just let-er-rip and take more than just 2 shots, so you have different widths to experiment with.<br><br>
You may wish to use manual exposure and white balance settings, so all the shots match.
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Joaquim,<br>
Any brand of lens should work, doesn't matter. The problem is the 45 degree erecting diagonal, and/or the extension tubes you're trying to use. There isn't enough room in the light path for those. Read Joseph Wisniewski's response to my first thread on this subject (follow link given in first post above); he explains the registration distance problem. Also have a look at the first picture I posted above, and notice how close the back of the eyepiece is to the ring where the lens is mounted. There's just a few millimeters between the back of the lens and the front of the eyepiece. <br><br>
If you get rid of the diagonal, and hold the eyepiece right up to the back of the lens, so close that they are <i>nearly</i> touching, then you should be able to focus on anything. But, your image will be inverted, unless you get that special eyepiece I described that has the erecting feature built in. That's why that eyepiece was such a find, and warranted me putting up this article in the first place. It seems to be the <i>only</i> one that will work to give you an upright image with a camera lens. <br><br>
Good luck. <br><br>
Darren
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<i>The command 34H needs to be sent to the lens to activate the VR feature according to fig.12.. So, you'd have to send a low pulse to the lens, wait for the signal low back from the lens, clock clk and simultaneously send 34hex on the si/o pin.</i><br><br>
I'm thinking (hoping) that isn't not going to be that complicated after all. Considering that the "power zoom" feature spelled out in the patent was never implemented, I bet the "motion control" features weren't either. The patent just covers lens-to-body communication. But the VR on/off switch is on the lens, not on the camera body. So I don't think the body knows/cares whether the lens has VR, and doesnﾒt have to command it on. (There's no EXIF tag for VR status, is there?)<br><br>
I think all I need to do is send the appropriate conditioned voltages. If the lens gets power, and the VR switch is on, it should work. (Or so I'm guessing.)<br><br>
I'll need to send one voltage between VCC (1st pin) and GND (mounting ring), and another between LBAT (6th pin) and LGND (7th pin). Probably okay to intermingle the grounds too. (On my kenko extension tubes, the 7th pin is connected to the mounting ring.)<br><br>
Remember above there was discussion about why VR and AF-S work on an N65 but not an N55? It doesn't have anything to do with # of focus points. The N55 only has 5 pins to the lens, instead of 7. It's missing pins 5 & 6, which includes LBAT. (Well, it may have the physical pins, but according to the circuit diagram, they're not connected to anything.) So that's why VR won't work, it's not getting power.<br><br>
Still, I haven't found definitive documentation on what the appropriate voltages and currents should be, I don't have the right equipment to measure those values coming out of my camera, and also, I don't have the knowledge to design and construct a voltage conditioner... So I've still got a bit of work to do before I can test my theory. Maybe this fall I'll have some time for further research.<br><br>
But if anyone else wants to step in in the meanwhile... Could be a fun project. <br><br>
Darren
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I'm going back to Maine next weekend. Here's one from last year.<br><br>
Darren<br>
<img
src="http://andrew-lorenza.atspace.com/album6/images/DSC_1179.jpg"
alt="Maine" width="902" height="600">
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Thank you Joseph, those old posts of yours you referenced were extremely helpful. I never considered that all the info would be in their publicly available patents.<br><br>
I don't really have a lot of time to delve into this project full steam right now, but I was very encouraged browsing the AF-S patent quickly. Lots of references to "motion compensation". According to figure 8, command 34H is what I'm after. Or, maybe that's a red herring and wasn't implemented (you can't disable the VR from the body after all), in which case probably all I need to do is close "switch 34" (the shutter button halfway down). According to Figure 6, pushing this button sends regulated voltage directly to the lens via the VCC pin (and also the camera's processor). The lens also gets unregulated battery power to another pin continuously. <br><br>
Figures 11 and 12 show various input voltages and waveforms, which would be necessary to send a command to the lens. (It doesn't seem to include an index of commands anywhere though.) But maybe I'm lucky, the "motion compensation" command isn't really needed, and all that would be necessary is sending those two voltages. <br><br>
I don't really have the equipment or experience to actually measure the signals/voltages coming out of my camera. I'm a MechE, not a SparkE... <br><br>
If anyone else is interested, you can view the full patent here: <br>
But, as that's a raster file, you can't search the text. But you could here: <br>
<a href=" http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=5,727,241.PN.&OS=PN/5,727,241&RS=PN/5,727,241">official US patent office website</a><br>
(That <i>should</i> include all the images too, but it's buggy on my computer, I only see the top inch of each page.) <br><br><br>
Making progress! <br><br><br>
<i>Robert wrote:<br>
VR almost hurts my eyes when I am shooting with its wacky movements and jumps.. I think I would prefer a scope without!</i><br><br>
To each his own... <br><br>
Darren
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<i>there seem to be 7 connections, not 8.</i><br><br>
Agreed, my D100 has 7 visible connectors too. (Maybe the 8th I saw in the schematic is a ground connected to the mounting ring?) <br>
My least advanced lens (50mm f1.8) only uses 5 of these connectors. But my most advanced lenses have 10 pins on them! Obviously, there's some future capability Nikon has planned for.<br><br>
<i>Apparently VR operates in different ways depending on whether...</i><br><br>
It depends on which lens. My oldest VR lens is the 80-400, which has a 3 way switch - VR off, VR on momentarily when you take a picture, and VR on continuously while you press the shutter halfway. But I doubt the camera knows or cares which way the switch is set, and sends the same signals to the lens either way. <br><br>
The newest models just have a simple on/off switch for the VR feature (or on/off plus active/normal in the case of the 18-200). <br><br>
So, maybe there isn't s special signal from the camera dedicated to communicating "turn on VR now". But there probably <i>is</i> one that says "the shutter button is now being held down half way". <i><b>That is the signal I'd like to replicate.</i></b><br><br>
Darren
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Peter,<br>
I doubt it's a multiplexed signal. Even if it were, what I'm proposing wouldn't be impossible, just a bit more difficult. But considering that really not all that much information needs to pass between the camera and lens, I doubt it needs to be that complicated. (Lens tells camera it's focal length, and focus distance. Camera tell lens to adjust focus fore or aft, to turn VR on or off, and provides power. Anything else?)<br><br>
And I believe Roberto is right, the VR and AF systems must work independently of one another. (Note that VR does not stop working in low contrast situations, when AF does.)<br><br>
A few months ago, I studied the repair manual for the N65, which includes a full schematic and circuit diagram. The Front Body FPC (flexible printed circuit) seems to have 8 connectors for the lens. They are identified as follows:<br><br>
VCC<br>
R/W1<br>
SCK<br>
SI/O<br>
R/W2<br>
LBAT<br>
LGND<br>
DGND<br><br>
But, I don't know what all those stand for. Any EE engineers recognize standard abbreviations? One could assume that LBAT and LGND are battery power and ground, and DGND is a digital ground for the signals, but I can't hazard guesses for the others.<br><br>
You can view the N65 repair manual, parts list, and plenty of other old Nikon documents here:<br>
<a href="http://www.micro-tools.com/pdf/Nikon/pdf/">http://www.micro-tools.com/pdf/Nikon/pdf/</a><br><br>
That would be a good place to start, if you're interested in reverse engineering.<br><br>
Darren
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I had my SB-800 for no more than 2 days before it went crashing to the floor. I
know, I'm a dumbass. The umbrella bracket I got came with a generic hot shoe
adapter, with a little screw on the side to "lock" the flash in place. But, it
just uses friction, it's not positively engaged in anything. I should have
known better. I went to adjust the umbrella, jostling the stand, and the flash
slipped out of the hot shoe. I managed to deflect it with my foot, so it didn't
hit the ground with full force, but the pop-out wide flash adapter / diffuser
was broken off.<br><br>
Bummer! <br><br>
(Okay, so now I know I ought to screw the AS-19 stand that came with the flash
into the umbrella bracket, rather than using the generic hot shoe. Or, I should
drill a hole in the generic hot shoe, so the flash's locking pin has something
to engage in.)<br><br>
Lucky for me, I don't live far from Nikon's west coast service center in El
Segundo, so I stopped by on my way to work Monday morning. I'm a heck-of-a-nice
guy, smile and say please and thank you, so they gave me the replacement part
for free. Nikon Service has always been good to me. <br><br>
It wasn't until later that I realized it was most definitely NOT designed to be
end user installed though... I guess the girl at the counter who gave me the
part didn't realize that either... I did manage to get it installed without any
disassembly, but only after a lot of frustration, cursing, etc... <br><br>
Don't attempt this if you are not mechanically inclined! <br><br>
The translucent part (that broke off) is attached to what I'll call a "slider".
You'll want to remove it, so you can have a look at it. It can't be pulled
straight out obviously, so you've got to rotate it sideways first. Make a hook
out of a paperclip to manipulate it. Be careful with the spring that's attached
to the front (that pops the diffuser down). <br><br>
You can now see how the diffuser attaches to the slider. The diffuser has two
hinge points, that slip into holes in the slider. (One of those points is what
broke.) Since neither of these parts is very flexible, you can't just pop them
together. One side of the slider has a notch behind the hole, so you can slide
the hinge point into place from the back. <br><br>
Now you need to get the slider back into place. And then, pulled out all the
way. Bend a paperclip to pick up those two hinge points, basically to make a
handle you can manipulate the slider with. Slide it in sideways, straighten it,
and pull it out. Be careful with that spring! <br><br>
With the slider centered, you can't get either side of the diffuser in place.
Push the left side of the slider in slightly, and you can make just enough room
to get the right side of the diffuser in it's hole. While you're doing this,
you need to be lifting the spring with a tiny jeweler's screwdriver. It needs
to be on top of the diffuser, you can see a little notch for it. This takes a
bit of dexterity. <br><br>
At this point, the right side of the diffuser is connected to the slider, and
the spring is pushing it down. Now, how the hell do you get the left side of
the diffuser in the hole? The notch is farther back, and is blocked by the
quick reference card and top of the flash! <br><br>
I considered <i>slightly</i> disassembling the flash head. I figured I could
just loosen the bolts, and separate the housings just enough to make room,
without actually taking the thing apart. But the screws were so tight! I was
worried I'd strip them. And I knew that would totally void my warrantee... <br><br>
The answer was a bit of elbow grease, and dexterity... With my smallest
jewelers screwdriver in the hole on the left side of the slider and acting as a
lever, I was pulling the slider out, so it wouldn't be forced back in. With a
slightly larger jewelers screwdriver, I was prying open a larger gap between the
slider and quick reference card. Basically, I jammed the end of that diffuser
in the gap between the quick reference card and the slider, and with a jolt, got
it back far enough to reach the notch and pop in place. Just a minor scuff on
the quick reference card. It all works fine now. <br><br>
Not easy! Hope I don't have to do it again. <br><br>
But, it is nice when you can fix your own stupid mistake so quickly!<br>
(And not have to leave your new toy at the repair shop for a week or more.) <br><br>
Darren<div>
</div> -
To get it focused, I first mounted my longest lens (the one with a collar) on a tripod, and autofocused on a distant subject. Then I removed the camera, and put my converter on the back of the lens, with the band clamp still loose. I adjusted the position of the eyepiece back and forth until it was focused, and tightened the band clamp. <br><br>
Viola! <br><br>
If you make one, drop me a line! <br><br>
And if you want to help with "phase II", adding a battery and circuit board to fire up the Vibration Reduction, please reply to my next thread... <br>
Darren
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I wonder if there's anyone out there, that either has access to internal Nikon
specifications, and wouldn't mind leaking a little bit of info, perhaps an
electrical engineer with an oscilloscope and a knack for reverse engineering.
<br><br>
I would like to know what electrical signals need to be sent to a VR lens to
turn the VR feature on and off. I assume it's more complicated than just
applying a given voltage across two pins (but wouldn't that be great if it was).
Rather, I assume a constant voltage is applied across two pins, and a binary
code with a "VR on" or "VR off" code is sent to other pins. I want to know the
appropriate pins, voltages, and on/off codes. <br><br>
Bonus points if you can also supply a circuit diagram on how to replicate that
signal with radio shack parts! <br><br>
What's this about? Read my last thread: <br>
<a
I built myself a Lens Scope Converter, but wouldn't it be so much nicer to have
a Scope with Vibration Reduction? It bugs me that I've got this really useful
feature built into my lens, but I don't know how to switch it on... <br><br>
I considered buying an old N65 and ripping the electronics out, but I found the
service manual, and became discouraged when I saw the electronics are
interspersed over several flexible circuit boards that would be difficult to
remove and repackage. Leaving the electronics in place, and removing the
shutter box and installing the eyepiece in it's place would be easier, but it
wouldn't be a very elegant looking contraption, now would it? <br><br>
Darren
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If you don't care about G lens compatibility, use any old rear lens cap. If you do care about G lens compatibility, I recommend you use one that came with a Sigma brand lens. <br><br>
When I started buying Sigma lenses, their rear caps really annoyed me. I was always fumbling to get them on. Whereas Nikon caps can slip on in any of 3 orientations, the Sigma only goes on one way, and the alignment dot is hard to see. For this reason, I had replaced all my Sigma caps with Nikon caps before I began this project, and had a few lying around. (Individually, Nikon caps are expensive, but I found a cheap 5 pack on Ebay.) Only going on one way is important, so the little doohickey you're going to attach will always be aligned with the aperture lever. <br><br>
With a G lens, you don't have an aperture ring to open up, so in order to let in the light, something has to be pushing open the aperture level that connects to the camera. Fortunately, it needs to be pushed in the same direction you twist the cap, so a simple 'stop' inside the cap will do the trick. It takes a bit of care to measure and place it in just the right spot. Since I knew I couldn't align it perfectly, and didn't want to risk bending the aperture lever by twisting the cap too far, I chose to make the little doohickey out of some high density foam I had lying around, instead of rigid plastic. The foam will give before the aperture lever does. This stuff had a self adhesive back, and was easy to cut, so it was convenient to use as well. (I think it came from an electronics shop, but I'm not sure. An old roommate left me with a few blocks of it.) If you can't find something like that, maybe cut off a bit of a kitchen sponge, and glue it in place. (Self adhesive weatherstripping foam may be a bit to pliable to actually push the lever, it has to be high density foam.)<div>
</div> -
I wanted to save my extension tube though, (for potential use in phase II of this project - see my next thread), so I fabricated my own attachment using a piece of a plumbing fitting I bought at Home Depot for $1. A pipe band clamp locks it in place. Here's a view of it disassembled. Notice in the pictures above, I put some black electrical tape around the band clamp, mainly for aesthetics.<div></div>
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What you need: <br><br>
Basically, this is pretty simple. Take a telescope eyepiece, and affix it to a rear lens cap. However, if you use a normal telescope eyepiece, you'll wind up with an inverted image. To get an erect image, you need to use an inverting eyepiece. Surprisingly, there seems to be only one such animal on the market! It's made by Skywatcher Telescope. Their info page is here: <br>
Unfortunately for many of us, they don't seem to have any dealers in the USA. Several Canadian dealers have it though. I got mine here: <br>
(After a debacle. I initially ordered one from www.mckittricks.ca, but they sent me something else. Apparantly they never even stocked it, and had mistakenly pasted it's description on their catalog page for another part.) <br><br>
European customers have many choices: <a href="http://www.obm.co.uk/products/db/794.htm">option 1</a>, <a href="http://www.1stoptics.com/pl/productdetail/2033?type=Telescopes&manufacturer=OVL%20-%20Sky-Watcher%20%2F%20Helios%20%2F%20%22Tal%22%2F%20Acuter&producttitle=10mm%20Erecting%20Eyepiece&productdesc=10mm%20Erecting%20Eyepiece%20-%2031.7mm%20format">option 2</a>, <a href="http://www.dhinds.co.uk/pages/fullProd.php?id=409">option 3</a>, <a href="http://www.pulsar-optical.co.uk/catalog/product_info.php?products_id=685">option 4</a><br><br>
It comes in a kit with a plastic extension tube, which you could cut down and glue directly to a rear lens cap you've cut a big hole in.<div>
</div> -
Here's it attached to an 18-200mm lens. This becomes a 1.8x - 20x magnification scope. The magnification is equal to the focal length of the lens, divided by the focal length of the eyepiece, 10mm is this case. With my 80-400mm zoom, I've got a 40x scope, which I use often to gaze at the moon.<div></div>
How to make your own lens scope converter for ~ $35
in Nikon
Posted