Lens question
in [Digital Cameras]
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From: Ray Fischer on 3 Nov 2009 13:04 John Navas <spamfilter1(a)navasgroup.com> wrote: > J�rgen Exner <jurgenex(a)hotmail.com> >>John Navas <spamfilter1(a)navasgroup.com> wrote: >>>Standard Optical Zoom "only" goes up 1o 480 mm, >>>and Extended Optical Zoom goes up to 860 mm, >> >>What is "extended optical zoom"? An addon-lens? > >Automatic cropping of the image. What makes it better than cropping in >post-processing is the ability to see a magnified final image. A "digital zoom" as it's more commonly known. Reduced resolution. -- Ray Fischer rfischer(a)sonic.net
From: Ray Fischer on 3 Nov 2009 13:10 John Navas <spamfilter1(a)navasgroup.com> wrote: > -hh <recscuba_google(a)huntzinger.com> wrote in >>John Navas <spamfilt...(a)navasgroup.com> wrote: >>> Bob Larter <bobbylar...(a)gmail.com> wrote >>> >John Navas wrote: >>> >> tony cooper wrote: >>> >>> Chickens, perhaps. �Turkeys, ostriches, >>> >>> emus, and caged birds maybe. >>> >>> Large birds that you can close enough to touch. � >>> >>> >> Standard Optical Zoom "only" goes up 1o 480 mm, >> >>Versus a dSLR combination of 448mm at f/4.0 .. > >What lens (including price, size and weight, >and how long you've owned it)? A 70-300 zoom can be had for $200. That's a 112-480 equivalent on a 1.6x crop body. I've had one for many years now, although I don't use it anymore since I prefer better lenses and my camera le's me upgrade to a better lens. -- Ray Fischer rfischer(a)sonic.net
From: No spam please on 3 Nov 2009 08:41 "John Navas" <spamfilter1(a)navasgroup.com> wrote in message news:p4rue5h5r358h3m9dlcps4nhus5e30hjj9(a)4ax.com... > On Mon, 2 Nov 2009 17:00:53 -0000, "No spam please" > <me(a)spamnotwelcome.org> wrote in <hcnkdu$vmm$1(a)adenine.netfront.net>: > >>I believe that the fuselage is a Faraday cage so it will alleviate >>interference from outside the aircraft ... > > RF signals can and do penetrate windows. > > -- > Best regards, > John > Hello John. Yes, RF signals can penetrate windows and there is a relationship between the size of the window and the wavelength of the RF signal. This is why Faraday screens designed to stop 50Hz or 60Hz mains radiation can be made from wire grid instead of solid metal. Regards, Rog.
From: No spam please on 3 Nov 2009 08:43 "Dudley Hanks" <dhanks(a)blind-apertures.ca> wrote in message news:RSIHm.50288$Db2.19440(a)edtnps83... > > "No spam please" <me(a)spamnotwelcome.org> wrote in message > news:hcnkef$vmm$3(a)adenine.netfront.net... >> "Dudley Hanks" <dhanks(a)blind-apertures.ca> wrote in message >> news:Q2CHm.50238$Db2.18755(a)edtnps83... >>> >>> ">> "Mister, at this time you are required to turn off your pacemaker. >>>> When we reach 10,000 feet, you may re-start it. Thank you." >>>> >>> >>> George, that's about as good a way of encapsulating the issue as I've >>> read... :) >>> >>> Take Care, >>> Dudley >>> >>> >> Hi guys. >> >> Nice analogy but the wrong way round. When you visit a radar site or >> broadcast site you should see signs warning those with pacemakers not to >> enter. Pacemaker is the victim, not the perpetrator. >> An acquaintance of mine works in the world of radio but can't accept site >> visits to broadcast sites because of his pacemaker. >> >> Best wishes, Rog. >> > > Not really, I think George was lampooning the practice of turning off ALL > electrical devices during take-off and landing. Followed too strictly, > nasty things would happen... :) > > Take Care, > Dudley > Hello Dudley. Ah - I see what George meant. Thanks for explaining it to me. My guess (I may be able to check with a retired medical electronics technician) is that pacemakers are well designed with regard to interference to/from them because they have to work in hospital theaters and ICUs. Personally, I want to keep as far away from pacemakers as possible. Hope the same applies to you and George. Kindest regards, Rog.
From: No spam please on 3 Nov 2009 08:53
"John Navas" <spamfilter1(a)navasgroup.com> wrote in message news:vhrue5phalna19cjlgcj6jq0fs4470omoe(a)4ax.com... >>I recall reading a book documenting a 747 flight over the pond. When one >>of >>its radio transmitters was used then one of the fuel gauge sensors lost >>track of how much fuel was in the tank. > > I don't see how that is any way relevant. > >>I know that my cordless landline phone upsets my FM radio - not when I'm >>talking over the phone but when it is being charged. > > Your FM radio is cheap junk compared to aircraft systems. > > -- > Best regards, > John Hello again John and thank you for the posting. I'd better clarify the comment about the 747. If one system on the aircraft (the fuel gauge system) was not immune to intererference from another system on that aircraft (the radio transmitters) then why should we expect any immunity from electronic systems brought on board by passengers? Regards, Rog. |