My MacBook Pro has been having issues recently with the mouse button that’s under the trackpad. Today it stopped working completely- and when I looked, my battery was swollen and disfigured. Thank goodness it didn’t explode or catch on fire- on the weekends, I generally use the system as a laptop- and well the result wouldn’t have been good at all!
I have a Kodak Wratten 100×100mm square filter. An ND 4 gives 13.3 stops of neutral density- allowing you to photograph stationary objects where people, animals or vehicles are moving past without getting the moving subjects in the picture. So far, my limited testing has made this a filter that should get a lot of use for urban city-scape pictures.
Well, I’m two weeks into my first major Asterisk install, and it’s been going relatively well. I still don’t have carrier-grade SIP service- apparently lots of companies can offer SIP over the Internet, but most carriers can’t offer it across a room unless it’s to an outdated vendor-sold PBX.
Call center features in Asterisk (queues, caller position announcements, call recording) are good, though I ended up sending call recording to a RAM disk. I’m going through an ATA to a POTS line for E911 service while waiting for a carrier or two to get their SIP act together.
This weekend’s trip to Cape May, NJ was half-successful. I didn’t get any shots of the crabs- bad timing on the high tide and weather didn’t cooperate. But I think I got some fair shots of Ruddy Turnstones, Red Knots and various Peeps. I haven’t processed the images yet, but a quick look in Aperture showed some with great promise. I also stopped by Forsythe WMA, but by that time the rain and wind were in full-force. The ultra-long migrating shorebirds where the main focus of the trip though, so success on that count, even if I couldn’t get as close as I’d liked to.
Fighting the ‘You do not have permission to send to this recipient’ errors battle is never fun, but changing the “Full Mailbox Access” permission to decouple “Send As” permissions for users is probably a good overall strategy, but the willy-nilly way you go about which version of Exchange has it, and the fact that you can’t seem to simply put the plain English version of Exchange anywhere just aren’t any fun. Come on, Exchange is a behemoth with its own database- surely you’re not trying to save thirty or so bytes!
The “Send As” permission has been implicitly included in the “Full Mailbox Access” permission. By customer request, this behavior has now been changed to allow granting “Full Mailbox Access” without having to also allow “Send As.”
This change is implemented in the following versions of Exchange Server 2003:
This change is not included with Exchange Server 2003 Service Pack 2. If you have been running the Exchange Server 2003 Service Pack 1 version of Store.exe that includes this change, and you upgrade to Exchange Server 2003 Service Pack 2, you must install the Service Pack 2 version of this hotfix to retain the new behavior. This change will be included in Microsoft Exchange Server 2003 Service Pack 3. (source: http://support.microsoft.com/kb/895949/) Too much fun for me, how about getting things a little more organized in Exchange land?
Someone on a forum asked about the basics of exposure and metering, and I penned a response that was
well-received,so I figured I'd update it slightly and repost it here...
Your camera's built-in meter tries to set the exposure values for a 12%[1] gray exposure
(due to historical paper contrast values adjusted somewhat.) Center-weighted metering just uses the light
values from the center of the image, spot uses them from a specific point.
In general, you can "trust" that your camera's metering database has seen enough "similar" scenes that
it'll pick the right value in matrix or full-scene metering mode, or you can select what to meter based
upon the tonal range in the scene.
For example, if you have a rock in the scene that's around 12% gray and in the same light as your subject,
you can spot meter the rock, and use that to set your exposure value for the entire scene. If there's
something with the same tonal value as 12% gray, but in color you can do the same. If you know that say your
fresh snow is 2 stops higher than 12% gray, then you can meter off the snow, dial in two stops of
exposure compensation (or change either the exposure manually) and shoot away with the snow where you want it.
The same goes for a black subject- the camera is going to say "Hey, that's 12% gray!" so you need to dial in
negative exposure compensation to compensate for the fact that the black object is darker than the gray. You can
purchase gray cards to carry around, then you can spot meter off the card and get the lighting in the scene
matched to the camera's meter. Obviously, you have to put the card in the same light as your subject- such as
under a tree if you have someone sitting in the shade.With digital, it gets a little easier. You can simply shoot
something white, and examine your camera's histogram to see where the white part of the exposure lies. You want it
as far to the right as possible without going over if you want any detail at all, or right on/over the line if
you want to get a completely white, no detail exposure. If your white object is in the same light as your
subject, then you can set the exposure that way by spot metering (some advocate using a fuzzy white towel,)
but if your subject is in darker light, you'll have to open up the exposure to get a good shot- the easy way
is by dialing in an appropriate amount of exposure compensation. Learning to use your histogram is good- if your
camera doesn't do separate red, green and blue channel histograms, you may occasionally have an image where you
blow out one of the channels inadvertently. Learning what conditions that happens in is a good thing.Once you
meter a scene and figure out what your exposure is (because the camera will do the 12% gray thing, you may want
a scene to be darker and moodier, or lighter so there's no one 'correct' exposure, you get to decide what's
important about a scene.
You have three exposure values that you can modify:
ISO
Shutter Speed
Aperture
ISO is the sensitivity of the recording medium, in the old days it was "film speed." On digital, it's the
sensitivity of the sensor to light. All sensors have a "base ISO" that is their natural sensitivity (usually
100 or 200.) above or below that, the camera's electronics modify the signal to gain more sensitivity. This
modification comes at the price of sensor noise, which make the pictures grainy. In film days it was the size
of the actual grains- so we keep the term "grainy." The closer you are to the base ISO of your camera, the less
noise the picture will have, but the more light you'll need.Shutter speed is how long it takes the shutter to
expose your medium (film or sensor.)
Aperture is how much light is let in by your lens. The aperture number is a ratio, so the smaller the number,
the bigger the opening, or the more light that is let in.
High shutter speeds allow you to freeze subject movement and make it so that camera movement is less apparent in
the image. Large apertures have narrower depth of field, or parts of the image that are in apparent focus from
the plane of focus, which is parallel to your lens and sensor plane on most cameras (I won't distract you with
the exceptions.)
Each full value of ISO, shutter speed or aperture is what's called a "stop" of light. It halves or doubles
the amount of light necessary for an equivalent exposure. So, if you have 1/60th of a second at f/8 at ISO 400,
and you change any single value one stop, one of the other values must be changed in the opposite direction
to get an equivalent exposure- say 1/30th at f/11 at ISO 400 or 1/125 at f/8 at ISO 200.
There are a some "rules of thumb" that apply here in terms of getting a sharp image- the first is that it's best
to hand-hold a lens at a shutter speed that's 1/focal length or faster. So a 500mm lens needs 1/500th of a second
to hand hold for most people (some can go down to 1/250th, some need 1/1000th.) Obviously, this is only in terms
of camera/photographer movement- you need fast shutter speeds to freeze a subject's movement. Image stabilization
gives you one to three stops of photographer/camera movement above this rule of thumb. So, if you need 1/500th
you can shoot at say 1/250th or 1/125th and still not see much photographer-induced vibration. In real tests,
you'll often find that using a tripod provides a visibly sharper image than IS/VR does at slower shutter speeds,
and as you go down the scale, the effects are less noticeable, as they are on shorter rather than longer lenses.
The amount of impact depends highly on the implementation, in body or in lens. Currently, in-lens implementations
are better, but obviously have to be purchased for each applicable lens.
A new rule of thumb with digital is that you should try to keep your aperture at f/11 or wider (lower number.)
That's due to the diffraction limits of the physics of light combined with the sensor's photosite size. The
smaller the sensor, with equivalent resolution, the more diffraction comes to play, as well as the larger the
number of photosites. That's one of the reasons that a 6MP camera is "better" than a 12MP camera with the same
sensor size in terms of diffraction- which is not what the megapixel fans will have you believe.With people and
animal shots, a shallow depth of field isolates the subject and makes for nice images. With things like
landscape shots, generally you want a larger depth of field, and with a larger depth of field you don't have to
be as exact with your focusing. With a 6MP 1.5x crop factor (APS-C sized sensor) diffraction starts to impact
sharpness at about f/12.9. With 12.4MP, it comes in at f/8.9. So, you get about a one stop difference between
a Nikon D40 and a Nikon D2x, and the "pro" camera is more limited by diffraction than the "consumer" one. I think
that about covers it...
[1] Like most folks, I originally wrote 18% grey until I read http://www.bythom.com/graycards.htm
If you attended Secure Toronto and liked the image that I showed from my Niagara Falls trip at the start of my presentation, I’ve got it available online as a fine art image.
http://PaulDRobertson.imagekind.com/
I had a great time, and the interaction was some of the best this year.
Paul
Presenting at GAO was fun, and I’d like to thank everyone who participated. I wish we’d had more time to delve into some areas more deeply. I hope the information will be useful in the auditing environment as you move forward, and that I sparked enough thought about emergeing technology and security to help you prepare for what’s coming.
Anyone who attended the Citi Webinar Monday may contact me directly via e-mail if they have any follow-up questions from my presentation. I thought the event went extremely well, and hope to do more such training in the future.
I’ll be presenting on Creating A Forensics-Friendly Environmnet for ISC^2 In Boston on the 13th of November for SecureBoston. ISC^2 are the folks who do CISSP certifications. Their new continuing education requirements are met in part by attending training sessions they put on. My understanding is the training is seating-limited, but free to CISSP holders. More information is available at this link:
https://www.isc2.org/cgi-bin/events/information.cgi?event=38
Paul