Board Camera Lenses

NO U CANT
u cannot take a camera on a internation flight cause of Terrioust alert that has been happing in uk. u cant take on lquids or shampoos even drinks r banned

2006-08-15 20:34:49 by David C

These board camera lens are most common used in different CCTV cameras with different viewing angles, from 11 Degree to 170 Degree. They are all ...

I have seen many people with their camera on board.
I guess your question is related to the recent incident at the London airport(s) where due to a terrorist warning, there was a strict rule in place where you couldn't carry really anything on board. So if you're flying from London, you may still have problems unless the situation is back to normal.

2006-08-16 18:01:28 by David C

Special optic glass for CCTV Cameras
Designed for use board camera modules such as those in fixed lens dome and case cameras
Horizontal Angle of view: 81.1°

i am curious as to what the best high def camera there is for a reasonable price. it would be getting used to film a short film and skate boarding type of videos. good quality camera with removable lenses possibly for no more then $3000

"Best" video quality is from miniDV tape getting HDV format video. The list is pretty short:

Sony HDR-HC9
Canon HV30
Sony HVR-HD1000U
Sony HVR-A1U
Sony HDR-FX1 (maybe)

The HV30 is the least expensive consumer cam that has 24p and 30 options. Because of its price, you can get accessories like an additional high capacity rechargeable battery, Glidecam/Steadicam device, good tripod, 2x tele lens, wide angle lens, fisheye lens, external mic, camera bracket (to hold the external mic), sturdy case... and as a MiniDV tape based camcorder your computer needs a firewire port - so if your computer does not have one, hopefully, it has an available expansion slot so you can add one... and a firewire cable... and an external 500 gig drive JUST for the video project work (HDV uses 44 gig of computer hard drive space per hour of imported video).

The lenses are not removable for any consumer or prosumer camcorder - but with threads at the lens, you can add different lenses and filters.

Don't bother with hard drive camcorders - the potential for shock in the rough environment you will be in could park the hard drive heads and prevent video capture. If you must go that route, go the direction of flash memory - AVCHD compressed high definition can be a challenge to edit, so be sure your editor can handle AVCHD video from the specific camcorder model you select. AVCHD compresses a LOT more than HDV, so quality is not quite there, so be very careful.

Don't bother with DVD based camcorders - they barely make decent doorstops.

2008-10-16 19:18:04 by Rawr1984

Mount: 12 * 0.5mm
Angle of View: 54 Angle
Focus Length: 6mm

Looks long, but is Highschool stuff.


Imagine that you work for NASA. You are thinking of requesting funding to send a new probe to Mars. You need to work out roughly how much it will cost.

There are two possible techniques you can use to get into orbit around Mars. As your probe approaches Mars, it will be traveling very fast (a high speed is necessary to get from the Earth to Mars in a timely way). If it is to go into orbit around Mars or land, it needs to slow down dramatically as it gets close to the red planet. This is known as the "orbital insertion maneuver" and is fraught with difficulty - many probes have failed to make this and have been lost.

There are two basic approaches. One is to use retro-rockets to slow down the probe once it gets to Mars. The trouble with this is that it adds to the weight (and hence cost) of the probe, as you have to carry lots of fuel plus a large rocket system with you all the way from Earth. Also, the rocket fuel will probably have frozen solid during the trip from the Earth, so you have to build in heaters to warm it up before firing the engine. This doesn't always work well, and even a small blockage could spell disaster.

The alternative approach is to use aerobraking. You dip your spacecraft into the upper fringes of Mars' atmosphere, and use friction to slow it down. In principle, this allows you to dispense with retro-rockets. But it does require very accurate targeting - you have to hit a very narrow "target window" in Mars' atmosphere. Too low and the friction will be too great, your space-probe will break up and crash. Too high and the braking won't be enough, you will skip off the top of the atmosphere and plunge on in the general direction of Jupiter. This "target window" can be only a few hundred metres wide.

You are planning to use the aerobraking technique. This means that you will have to navigate your spacecraft with great precision. Great precision can be achieved, but it comes at a price - you have to work out how large that price needs to be. The cheapest method is to use gyroscopes to measure the orientation of the space-probe, but they tend to get shaken up by the launch vibrations. More accuracy can be achieved by having star tracking cameras on board. The bigger the lenses of the camera, the more accurately it can orientate the space-probe. Greater precision still can be obtained if you use ground-based telescopes to regularly monitor the position of the probe en route, and have an on-board set of small thruster rockets which can nudge it back to the correct path, if it has drifted off.

In addition to pointing the right way, the rockets that propelled the probe away from the Earth have to give it a very precise speed. Mars is a moving target, and any error in the initial velocity will mean that you arrive at the right place at the wrong time, when Mars is somewhere else.

Imagine that you have to hit a target window that is 500m wide. Your spacecraft leaves from Earth, which is a distance of 100,000,000 km away. Assume that the spacecraft travels in a straight line. You work out in what direction the spacecraft must set off. But what uncertainty can you tolerate on this direction, and still be sure it will successfully aerobrake? You may use the small angle approximation if you wish.

x degrees.


Your probe will travel at a speed of 10 km/s. But Mars is moving sideways, as viewed from the Earth, at a speed of 20 km/s. If the space-probe was aimed precisely at the middle of the aerobraking window, what uncertainty in its travel speed can you tolerate?

y km/h

What are x and y??

o = 250m
a = 100000000000m

x = tan (o/a)
x = 4.3633231299858239423119959717081e-11 degrees maximum trajectory deviation

Mars moving at 20000m/s so it will move 250m in .0125 seconds, since we're initially aimed at the center of the 500m window then that .0125s will put us out of the window. To go the 100Gm at 10km/s it'll take 10 million seconds and since we will miss the window if we are .0125 seconds too late or too early, and .0125 is 1/800000000th of the total time of the trip then if our speed is deviated by 1/800000000th either too fast or too slow then we will miss.
y = (10,000m/s)/800,000,000
y = .0000125m/s uncertainty

2009-03-10 04:19:54 by Top of all Answers

I have finally made the plunge to a digital SLR. I've ordered my Cannon Rebel XSI with an 18 to 55 mm zoom lens. In my ancient past, when I shot film, I had a good selection of lenses. And I had a pretty good idea of the degree of magnification for the range of focal lengths. For example, I knew what my 100 to 200 mm zoom lens was capable of. But now, as I researched the specs on digital cameras, a whole new set of parameters had to be learned. On my point and shoot digital, I understood that 3X, 5X, 10X optical zoom could be pretty meaningless as what was 5X to one manufacturer was something else to another. But, when it comes to DSLRs, the standards seem to apply across the board, but that doesn't help me understand what to actually expect in performance.

My question is: Can someone copy a table, or please provide a link to one, showing a comparison of film camera lens focal lengths to those of digital camera lenses? Even if not a complete table, one that might show me what today's equivilant is to the old 50 mm 100 mm, 200 mm, 500 mm lenses would be helpful.

Thanks.
Thanks, "proshooter," for your quick answer.

So, if I got this right, if I wanted to find a digtal lens equivilant to an old 500 mm, I divided 500 by 1.6 and got 312.5. So, I'd be looking for something about 300 to 325 mm in the digital formats? Is that right?

the XSi has a crop factor of 1.6 so your 18-55 lens has the view of a
a 28-88 mm lens on a film SLR, or a DSLR with a full frame sensor.

Just multiply the focal length by the crop factor to the effective focal length for your camera , for every lens and focal length.

http://photography.suite101.com/article. cfm/digital_camera_lens_crop_factor

2009-03-23 15:58:36 by Vince M