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OT: Camera Guys get in here....


BottomHeavyKate

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How does that work? The human eye can see a field of almost 180 degrees.



Not really, out of BOTH eyes you can see probably about 120' or so, talking focusable area, being actually able to percieve detail.. significantly less.

One eye probably has an angle of view somewhere around 45'-60' which is somewhat similar to a 50mm lens in 35mm format, a 45-60' angle lens say in a medium format (6X6 film) is around an 80mm lens, it to do with the angle of focusable area..

this is a pretty lame way of explaining it sorry, its easier with diagrams.. I failed optics at Uni :facepalm:

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How does that work? The human eye can see a field of almost 180 degrees.

 

 

It's not so much about angle of view as it is spacial relationships.

 

Telephoto lenses compress space and make background objects appear much closer than they are to foreground objects. Wide angle lenses expand space and push things away. A standard lens (50mm) will keep spacial relationships equivalent to what the human eye sees and look more "natural".

 

It's hard to explain, but I hope that helps.

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To try and explain the distortion issue and the 'more light per f stop' bit...

A proper wide angle lens does not distort the view as such (at least a well designed one, though there are badly designed lenses, and fish eyes that do muck this explanation up somewhat). So the image on film is undistorted and exactly as the camera sees it through the lens.
What it does do though, is change the perspective shown - our eye is used to being able to see a set field of view (equivalent to the 50mm 'standard' lens used on a 35mm film body) which is what we percieve as natural. A 28mm lens on the other hand has a much wider field of view, so fits 'more' into the image, which seems unnatural to us and hence looks 'distorted' despite being optically perfect.

On the point about aperture/light gathering ability - I think someone has gotten mixed messages before, as the explanation includes a couple of extra factors.
f2.8 lets in exactly the same amount of light whether the lens is a 28mm f2.8 or a 300mm f2.8, which is a set fact and cannot be argued.
What does change, and was possibly missed out before is the depth of field - If you take both lenses and focus on a point say 10m away, you will find the depth of field of the 28mm lens will be much larger than the fairly narrow dof of the 300mm lens. So if you want a depth of field of x size, the 300mm lens may require an aperture of f11 to get everythign in focus, while the 28mm will have a much wider aperture of f4 or whatever - so in these conditions you will get a much faster shutter speed with the 28mm lens which is where I think the idea of the wide angle bringing in more light per f stop (it doesn't, but you will get more depth of field per f stop)

How does that work? The human eye can see a field of almost 180 degrees.



The human eye is a rather fancy device, to which it is actually surprisingly hard to generalise in such a way without being wrong in some form or another.
The eye is really split into two areas - a fairly small area of 'sharp' view, and the surrounding area of periphery vision. To focus on an object your eye uses a rather narrow field of view to gather the image, but continually moves around to piece the full picture you see in your head. At the same time your periphery vision scans around elsewhere, which is how you can glimpse something out of the corner of your eye - your periphery spots the movement, but as you didn't 'look' at the subject with the accurate area of your eyesight you cannot see it properly. In this way you can spot something over a fairly wide field of view, which your eye doesn't really have the ability to use...

In the end your eye is a hugely complicated tool, with a huge array of movement and complications all far outwith out control, though most bodies do a good job on their own ;)

Comparing the eye to camera optics, a 50mm lens is roughly the equivalent to what your eye will see, and produces an image as natural looking as possible (without the shift in perspective of very wide or long lenses)

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So I'm looking for a new digital camera. I've decided first to go with the Olympus Water/Shock/Freeze proof camera. It will be great for my hunting, fishing, camping trips, and hold up better to my clumbsiness - which is the reason I'm shopping for a new camera anyway
:facepalm:

So I've got all the models lined up and I basically have to decide between the standard one and the wide angle lens one.....


What the hell is a wide angle lens? How does it affect the pictures?


Here are the ones I'm looking at....


http://www.newegg.com/Product/Productcompare.aspx?Submit=ENE&N=2070070012%2050001000&StoreType=-1&CompareItemList=N82E16830111211%2cN82E16830111240&bop=And


Then I start saving for the big fancy DSLR
:love:




A wide angle lens is what I use to take pictures of the in laws......:lol:

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My mom works at a chemistry lab and she went to an Olympus conference. She said they had these on display under running water and it worked perfectly.


I fish and I routinely drop my camera from my tree stand
:facepalm:

The wide angle lens will be cool for those mountain landscape pictures I love to take too....





You fish from a tree?

Maybe a good laynard might be a good idea to go with the new camera :poke:

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Back in my teens I used to sell cameras on weekends and Olympus were always a good bet (having said that, nearly anything from Canon, Nikon, Olympus or Pentax is ok)..


I like the Oly compact digitals, very user friendly, take nice pics, well made, can't really go too wrong and the waterproof, shock proof thing is pretty cool, we get a great TV commercial here on OZ TV for them with a big mastiff dog named Norm!


Foy you, the wider one would probably be better (landscapes n stuff), the zoom tele difference between a 102mm and a 114mm is fairly minimal, but the difference between a 28 and 38 is huge.. 38 is about as hopeless as can be for a wide angle..


I'd definitely pony up the extra for the wideangle one..



Thank you for mentioning Pentax...no one ever does.

:thu:

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Couple of points to consider.


First, the earlier link to DPReview is excellent - lots of great info there. Also check out
- TONS of excellent info/reviews/etc. on all things digital camera. If anything there is too much, and it's easy to get overloaded.


About the wide angle thing: The little graphs posted earlier explain "wide angle" kind of but they leave out a crucial consideration. It's not simply a wider frame that you get (that's actually a panorama, not a wide angle). It's more like a wider view
compressed
into the same frame. You DO get some distortion of the image & perspective with a wide angle lens. You've probably seen pictures taken with a "fisheye lens", yes? And you've seen how everything is all scrunched together and sort of bent, right? Well, a fisheye lens is nothing more than an extreme wide angle lens. And all wide angle lenses distort like that to some degree. A 40-50mm lens is sort of "normal", like what the human eye generally sees. An 18mm lens is pretty much a fisheye and is obviously distorted. Anything in between will be distorted in varying degrees depending on which end of the scale they fall. So be mindful of this when purchasing a "wide angle". The effect isn't necessarily "wrong" or anything - it can of course be really cool. Just be mindful that you WILL get SOME distortion of your images and make sure that's what you want.


Another nice thing about wide angle lenses is that they have a deeper field of focus, and generally bring in more light per f-stop, so it's a bit easier to catch a good shot sometimes. For this reason, something like a 32-34mm is great to have for a "snapshot" camera or one that is mostly used for action shots (sports events, concerts, etc.).


One more thing about digital cameras - and my pet peeve. Just about all affordable digicams have a bit of an evil little thing called "shutter lag". This is a short time between when you press the button and when the actual photo is taken. I find this unbelievably annoying and extremely frustrating. If you take anything other than posed still shots or landscape scenery pics, this delay often makes the camera essentially useless. So, when shopping for cameras, look very hard at that spec. Make sure that there is the smallest possible lag that you can get, or better yet none at all. Try the cameras out and don't even consider ones that have a noticeably long delay. Many of them feel like it takes seconds between "click" and shutter release. Be prepared to spend more for one that has no appreciable lag.

 

 

you really consider 18MM fisheye?

 

I thought fisheye was the manner in wich they made the lens concane like a fish's eye.

 

10-16 MM is generally considered super wide angles from what I have seen.

 

to me 18-50mm is what the human eye sees.

And lets not forget sensor size in relation to lenses.

 

the sensor in my Kodak z 612 is much smaller that my almos full frame sensor in my Pentax.

 

makes a big difference when going 8X10 or bigger

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you really consider 18MM fisheye?



Not any more :)

The two middle paragraphs of my post have been "corrected".


But, the point was that an 18mm lens doesn't just widen the frame (that would be a panorama, not a wide angle). It distorts the image to some degree relative to say a 50mm lens, and spatial relationships are changed. As well, the ones that are not corrected are certainly more "fisheye" than a "normal" lens. But I kind of mis-stated it.

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Not any more
:)

The two middle paragraphs of my post have been "corrected".



But, the point was that an 18mm lens doesn't just widen the frame (that would be a panorama, not a wide angle). It distorts the image to some degree relative to say a 50mm lens, and spatial relationships are changed. As well, the ones that are not corrected are certainly more "fisheye" than a "normal" lens. But I kind of mis-stated it.




I was just asking wasnt critisizing your statement.

And yes there is some vignetting on the edges of 18MM

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