Category: accessible Devices
Robozork made a topic about cameras recently, but he also made an excellent point about keeping it on topic, since his is for emergency use and alot of blind people can benefit from it. This one is for more relaxed times when you want to create pictures or videos of yourself for personal use, to put on Facebook, to show others etc. So let's start with stills. I want to take some pictures of myself, not only of my face but of me standing up, holding things, showing various clothing etc. I've got a camera in my Macbook but could never get the hang of taking pictures of me past my face. properly and even my face gives me trouble because it's not a movable camera. Since it's stuck in the screen, I can never figure out what angle is the best so that it's not taking images of the floor or the ceiling. It got so annoying that now, whenever I make videos, I cover the lens so I don't get nonsense from people about lighting or my face not showing up clearly/fully. What about if I wanted to take a picture of something that I'm holding or that's sitting on a desk or hanging up? How do I know that the whole thing will come out, especially if it's small? What about people? For some reason, I've been told that I tend to take good pictures of people, but these have only been with regular cameras. Back to the Macbook, how far should I be from it? Is it easier to use a detachable webcam? What about a regular camera like a Polaroid or a nondisposable? Do they work the same as the digital ones as far as technicalities or do they need to be more targeted? What is autofocus and does it come in varying levels? For example, robozork said that the disposibles don't have the autofocus capacity needed for emergency situations like he was discussing. What does that mean and does this carry over to fun pictures too?
Now onto video. The same questions hold true for the ISight camera in the Mac as for stills so I won't repeat them. But what about a regular video camera? I've heard that it's better to get one with manual as opposed to automatic controls, but is that only true for the sighted? In other words, are the automatic controls on video camera the same as the autofocus on the still ones, thereby enabling us to just put the camera on a tripod and video ourselves? What should I look for in such a camera? What features are the most important and what don't I need? I know of the zoom feature but is that truly usable for us? While it's easy enough to scan a photo with my flatbed and then have someone sighted crop it etc. How do I convert from vhs to a digital format, incase I want to put it on Youtube or something? I know that there are many programs for this but what's the most accessible? I was told, by Jesse, in my "Looking for a Camcorder" post that I'd need
"1- Video capture solution, such as an interface that plugs in with the AV cables from the vcr to a converter box, which would plug in via Firewire to your computer.
2- a program to decode such recordings once they get into the computer."
But I don't use firewire and the only computer that even has it is the Mac. Then again, there may be another option if I understood this correctly. Chinchillac said, in the same thread, "As far as I know most VHS recorders weren't available when computers came out originally so it may be difficult to find that has a USB cable that will attach. You might have to go with the older prong cables." I have serial, parallel and vga ports and pcmcia slots available. So which prongs are necessary and do I still need the actual converter box or can the software handle it? There are many vcrs in this house, but the one I'm using right now is built into the television. Would it be better if I used a separate one or would the connectors be the same? When did software for converting from analogue to digital first come out. Finally, if I wanted to buy one of those compact flash cameras, what should I be looking for as far as features and quality? Can anyone recommend a camera for me and do you take videos the same way with those as with the regular vhs ones? No matter what I buy, I want to stay under $100 (maybe $150 at the most), though, as was said, if I buy the conversion gear, it might go above that.
will try to answer your question 1 by 1.
firstly, as far as how to set up your webcam goes in a correct angle, assuming that you are sitting, and have your macbook oon the desk, in a 45degree posission (means the screen is on the strate line of your macbook, facing you. usually in such angle, you will pretty much get your upper body, from chest to let say neck. to take a self protret, try to bend the screen forward, in about 60degree angle, you will mbe most likely get a view of your neck, face, and head (provided that you sit strate on the chair in front of the macbook, working like how you work on your computer without banding forward, in about 2 to 3 foot away from your screen).
as far as the still camera and digital camera goes, is a tough question to answer. you are ask to compare a technology back in 1980/ and a technology that is in 2000s. one, as the name suggest, using digital, is all digitalize. a normal person can view the photo within second of taking it, and can use photo edditing software such as photoshop, and so on to make it look even better within minutes. one can choose what they want from the shots they taken, and save them, and delete those that they dont want. all these proces without the need of develop the photograph or print them. a digital camera can now up to 17megapicsal, but a normal person seriously dont need that. for less than $100, perhaps around $70, you can get a good decent camera that could last you 20years, and the maintainance of it is relative easy and low cost, always able to produce a better photograph.
for still camera, not too sure how many of those left in the market at the moment. is relatively bolky, have no capacity of viewing it once you take it, and high maintainance cost as to develope the photos, battery etc.
what is auto focus, well as the name suggest, auto focus basicly helpp to focus an object, or a person in a better condition. most camera (digital camera) nowadays come with this fitures, regardless of how much you pay for it. it is great for a blind photographer, cause it will help to focus the object you taken, in a better condition, better brightness, better zooming and things like that.
Thanks for the excellent explanation, especially of the angle needed for the Macbook. Is it possible to take one of me standing or just sitting?
if you want to take a standing pic from your webcam, will be harder, but is workable, you perhaps need to move the screen forward, talking about perhaps about 75degrees, and standing about 5foot away from the camera. you most probably will get a half-body pic. if you want full body pic, try standing about perhaps, 8 to 10 foot away, posissioning your webcam in a 50degree angle. you will be most likely to get yourself, in a very small and blur figure.
be aware, so far, a webcam only come in either 0.3, 1.3 or 2mega picsal, it don't have that strong capasity. also, the webcam in macbook, aint one of the better one, as far as webcam goes so, just be aware of that.
I really don't know anything about mega picsals. Is this like the picsals on the tv screen, vertical and diaginal? How is quality of a regular still camera measured? I know most use 35mm film but how do you distinguish between high and low quality cameras and is there a high quality film as there is with magnetic tape? I'll try out the suggestions for the Mac cam. They certainly sound easy enough, though I might want to get a protractor at some point. *smile*
if you want to take a photo or vedio on a camera (not webcam), assuming your target is right in front of you in a strate line, hold your camera still, in about 45 to 60 degree angle, (depends on the target's distant from the camera)and snap.
Well, if it's a video camera, the tape should usually be roling, unless I start it after I aim for the target. I'm betting, in that case, it's probably best to start before hand, since I don't want to lose my angle while fumbling with buttons. Then again, a tripod could probably work, providing it has the right position. I just need to make sure that I'm within the camera's lens if I'm videoing myself. As for still cameras, what about flash? When do I need to use it? If I get a Minolta Talker, it will actually tell me when it's too dark touse flash, but I mean in general. Do some cameras have a flash that automatically turns on so I don't need to worry about it? lol I'm asking way more photography and video questions than I thought I would.
*sigh* yes an no. megapixels are basicly a tiny little dots that make everything to be in one piece. so, in order to answr your question, it is quite right that a TV, print magazine, books newspapers, you name it, as long as they are print and or digital, made up of millions of dots.
however, to answer your question properly,
How to Define Megapixels
In The Beginning
The foundation of megapixels is the lowly pixel.
A pixel is one dot of information in a digital photograph. Digital photos today are made up of millions of tiny dots (Mega = Million).
This means that a 10 megapixel image contains approximately 10 million pixels, while a 14 megapixel image contains 14 million pixels.
Since a photo has a rectangular shape, the dimensions of one side aren't equal to the other. If we assume that we're looking at photo in landscape orientation:
•A 10 megapixel photo measures 3888 pixels wide by 2592 pixels high
•A 14.5 megapixel photo measures 4672 pixels wide by 3104 pixels high
If you take the width and multiply it by the height, you get the total number of pixels that make up the digital image:
•3888 x 2592 = 10,077,696 pixels = 10 megapixels
•4672 x 3104 = 14,501,888 pixels = 14.5 megapixels
This is just the tip of the iceberg - there's a lot more information required to define megapixels.
Is More Better?
So a camera with more megapixels takes clearer photos right?
After all, if one camera is capturing 14 million pixels and another is only getting 10, then the photo with 14 million pixels should look better.
Not exactly.
While a digital photo that contains 14 million pixels is physically larger than one with only 10 million, when viewed and printed at small sizes they are hard to tell apart.
The real notable difference is not one of quality, but one of file size: 14 megapixel cameras create larger digital files than their 10 megapixel counterparts.
A larger file size means:
•You need to purchase higher capacity memory cards (4GB or more)
•It takes longer to transfer an image from the memory card to your computer
•You need more hard drive space on your computer to store your photos
•You need a more powerful computer to organize and edit your images
•You must dramatically reduce the size of photos to send via e-mail
•It takes longer to upload the original images to an online gallery
This leads us to ask an important question: what's the point of cameras with more megapixels if image processing takes up so much time and space?
Large Print Sizes
First, the most obvious advantage:
You can print photos with more megapixels at large sizes.
Let me define this another way: if you print an 10 megapixel photo and a 14 megapixel photo at 4x6 inches (standard print size) you'll be hard-pressed to tell which one is which (just like when you compared the small images above).
But if you print both photos at 20x30, then you will see a difference in quality.
The 10 megapixel photo won't look as clear and as sharp as the 14 megapixel photo when printed at this large size.
Here's how to read the megapixel print size table:
•With a 10 megapixel camera, any print that you make that is 12x16 or smaller will look fantastic
•With a 6 megapixel camera, you can make high-quality prints at 9x12 or smaller
Can you print your photos larger than the acceptable size? You bet.
There's nothing stopping you from printing your 6 megapixel photos at 20x30, or even billboard size if you so desire.
But there is a catch: as you increase the size of a print above the acceptable print size, the image quality deteriorates.
A 4 megapixel photo printed at 4x6 will be perfectly clear. It will also be clear at 8x10. But a 4 megapixel photo printed at 11x14 will show a loss of image quality. The same image printed at 20x30 will show considerable loss of image quality.
BOTTOM LINE: If your goal in life is to make really large prints, then compare cameras with lots of megapixels. If you just want to print at 4x6 and e-mail photos to friends, then spending a lot on more megapixels is a bit of a waste.
More Image Cropping Options
You can now define megapixels in one way: more of them lets you make larger prints.
There is a second benefit to having a lot of megapixels in your photos: it gives you freedom to crop.
Let's say that you've taken a photo with an 8 megapixel camera - you're able to make nice 12x16 prints with this.
On a photo safari, you take a photo of an egret, but you're too far away from the bird and you don't have a telephoto lens to get up close and personal.
The primary subject of your photo is tiny. You decide to crop the shot so that the egret appears larger.
No problem...except that you can no longer print at 8x10.
You need 8 megapixels to print at 12x16 before the image starts to deteriorate. When you crop the image, you are eliminating pixels - let's say that you crop out 2 megapixels from your photo.
You wind up with a 6 megapixel photo - you can make a nice 11x14 print, but that's about it.
Now imagine that you take the same shot with a 10 megapixel camera.
With this shot, you can crop out a full 50% of the image (5 megapixels) and still make a high-quality 9x12 inch print.
But be aware that cropping and adjusting your photos takes time. In fact, it takes a lot longer to edit photos than to take them in the first place.
BOTTOM LINE: If you don't want to spend your time sitting in front of the computer editing and cropping your photos, then a camera with tons of megapixels doesn't provide you with an advantage.
Buying Tip
Let's conclude our introduction to megapixels with a quick summary of some of the reasons for and against getting a camera with more megapixels.
Get a camera with a high megapixel count if you:
•Want to make very large prints of your digital images
•Want to crop out large portions of your photos and still make large prints
Don't spend all your hard-earned money on lots of megapixels if:
•You rarely make prints larger than 4x6 inches
•You just want to upload images to an online gallery
•You enjoy sharing photos with friends via e-mail
There you have it: the mystery of megapixels has been clarified. That wasn't so hard, was it?
Now that you know what they're about, get out there and define megapixels for others so they don't have to stay in the dark!
http://www.digital-slr-guide.com/define-megapixels.html -
Wow! That was an absolutely fantastic article! Thanks! I understood it and I'm terrible at maths. *smile*
interesting