....and the floor won

[Anonymous]

No, its not a train but my camera.
I need to buy a new digital camera as I had dropped it on the floor the other day, and the floor won. What camera is everyone using?

[jimhaleyscomet]

I can not tell you the best camera...however...beware of any camera with a tiny lense.  In photography you need a fair amount of glass to get in enough light.  A tiny credit card camera with a tiny lense is going to take lousy pictures except when you have a ton of light (like outside) even if it has 8 or 10 megapixels.

I currently use an Kodak EasyShare Z612 with a 35mm lense that I got at Walmart recently for about $300. It seems to be a very nice camera.  It would be better with interchangeable lenses  but that  would double the price. 

Jim H.

[riverrailfan]

I second the Z612. I have a Z7590 and it takes great pictures and the battery life is very good. I wouldn't touch a digital with less than 10x zoom. Kodak makes a good digital camera. The Z612 is 6.1 mega pixel, 12x zoom lense and image stabilization. One option I wish my Z7590 had. I also own a Pentex DSLR to.

[luther_stanton]

I can not tell you the best camera...however...beware of any camera with a tiny lense.  In photography you need a fair amount of glass to get in enough light.  A tiny credit card camera with a tiny lense is going to take lousy pictures except when you have a ton of light (like outside) even if it has 8 or 10 megapixels.

If you consider something along the lines of the Nikon CoolPix a credit card camera, then I would disagree with the statement about lens sizes.  There are many more factors that simply lens size that determines picture quality.  The quality of the optics is one.  Cheaper cameras typically have fewer features with lower quality optics.  Specifically regarding what comes through the lens in terms of the amount if light, it is a combination of the aperture setting combined with the exposure time (shutter speed) that determines the quality of the picture.  I have both a Nikon and a Canon Digital Rebel XT.  One is a 4.5 Megapixel while the other is an 8 Megapixel.  Both take excellent pictures.  Of course the Canon has a the Nikon beat hands down with features, but they cost!  Many of the point and shoots now offer scenes or modes that will allow you to get a little more creative with your shots.

I wouldn't touch a digital with less than 10x zoom.

I suggest you look at optical zoom - not digital - as a fator.  Many of the digitals state large zoom factors when in fact they are using digital zoom which manipulates the pixels after the shot is taken - it is not truly changing the optics of the camera.  This is similar to what you do in your processing software - in fact the digital zoom will limit how much you can "blow up" your images for printing before pixelation sets in.  Of course, with a higher mega pixel camera this will be less noticeable.

I suggest you buy as much camera as you can afford, especially if you do a lot of photography.  I shoot a lot of moving train shots so the burst rate was important to me.  Many of the point and shoot models can not take "back to back" pictures quickly - my Nikon took about 2 seconds to process the picture and set up for the next shot after clicking - that is a long time when your subject is coming at you at 40 mile per hour.   Typically the SLRs will offer more features, quicker recycling times - my Canon can burst to 3.5 frames per second for 9 shots - but they traditionally command a higher price.  Also, there is often a longer learning curve to understand and take advantage of all the features.

- Luther

[Birds]

 

[ben10ben]

"I wouldn't touch a digital with less than 10x zoom."

In contrast, I would strongly suggest avoiding a superzoom. Zoom lenses are compromises anyway, and one with that much range typically will have lots of problems. You usually get a whole lot of barrel distortion on the wide end, and pincussion distortion on the telephoto end. In addition, most 10x zoom lenses have a maximum aperture of f11 or so at the telephoto end, which is difficult to deal with even in good sunlight. In addition, they typically sacrifice some distance on the wide end for more on the telephoto end, which I can promise you'll really miss if you're ever in a tight space and can't just keep backing up.

The only superzoom lens I would even consider using is Nikon's 18-200 3.5-5.6 VR lens, which has a retail price of $700 by itself. This lens still has its problems, although it's a lot better than what you'll find on a $500 fixed-lens digital camera 12x zoom. The 5.6 maximum aperture on the telephoto end is tolerable, although not great.

Were I buying a digital camera for myself(even though I still use film almost exclusively), I'd get a Canon A530. It sells for around $150, and has all the features any serious or not so serious photographer could want in a compact camera. I believe it has a 3x optical zoom(equivalent to 35-105 on a 35mm camera), and around 5 megapixels.

[jimhaleyscomet]

Luther,

While it is true that a good lense helps....all things being equal a tiny lense will require longer exposure times and/or a shorter f stop (limiting focus range).  Light gasp is proportinal to the square of the lense diameter so a lense twice as large collects 4x more light.  My son purchased a Sony 5MP camera with a zeiss lense.  He takes a lot of great pictures because it is so portable, but the low light capability is very poor.  We often end up with dark/blurred pictures inside.  The other thing about tiny cameras is the flash is so close to the lense you get more red eye.

Jim H

[ben10ben]

Jim,
F-stops are equal to the focal length of the lens(in mm) divided by the diameter of the aperture of the lens(in mm).

Most point and shoot digital cameras have lenses with really short focal lengths because they have really tiny image sensors. A lens with a focal length of 10mm on a digital camera, for example, may have provide the equivalent field of view of a 50mm lens on a 35mm camera.

Considering both equation for F-stops and the short focal lengths of most digital camera lenses, you can see how it's possible to still have a tiny lens on a digital camera that still lets in a lot of light.

Right beside me, I have two SLR camera lenses. Both have a maximum aperture of f2, however one has a focal length of 24mm and one has a focal length of 135mm. Both let in the exact same amount of light, however the rear of the 24mm lens is tiny, while the rear of the 135mm lens is huge.

In the past two years, there are a couple of areas where digital cameras, particularly compact digital cameras, have really improved. The first is in the area of high-ISO noise. At one time, digital cameras started showing showing noise(that stuff that looks like grain) at ISOs above 100. Now most compact digitals can shoot at ISO 400 with tolerable amounts of noise, and DSLRs can shoot at ISO 400 with almost no noise. The second is in the area of noise in long exposure. My 3-year old digital camera gets so noisy after a 1/4second exposure that you can't see any detail in the image. Todays cameras can easily go up to several seconds with no noise. These two improvements, combined with Image Stabilization/Vibration Reduction let cameras shoot in lower light without flash than they could before.

[lionelsoni]

I find it hard to believe that a 12-millimeter-diameter lens lets in "the exact same amount of light" as a 67.5-millimeter-diameter lens.  What happens to all those extra photons that hit the extra glass of the larger lens?  They wind up on the proportionately larger sensor.  For the same sensor performance, that results in 32 times as strong a signal as on the smaller sensor.  The lenses have been getting smaller not because size doesn't matter but because sensors have been getting more efficient.

If lens size were not important, the astronomers who have been putting the largest-diameter mirrors they can afford into their telescopes are on the wrong track.

[ben10ben]

Bob,
In my example, both of the lenses in question are designed to take the light reflected from a particular scene and project it onto the film in a circle that's 43.5mm in diameter.

The difference is that the 24mm lens is gathering light over a very great area. As a matter of fact, it's gathering light over 74 degrees on the horizontal dimension.

By contrast, the 135mm lens is only gathering light over 15 degrees,

Even though the 24mm lens has a smaller diameter, there are more photos being reflected back from the greater area it's seeing. The 135mm lens needs such a large opening because it's collecting fewer photons anyway.

Astronomers use big lenses and mirrors because they're working with long focal lengths.

All of this is, of course, assuming that the image circle size remains constant. If you need to increase the image circle size(to support a larger film format or sensor), you start seeing reductions in the amount of light being transmitted to the film. As a matter of fact, you start losing light as you focus a lens closer(move it further away from the film), as the image circle increases as a consequence. If a lens for 35mm has a maximum aperture of f2 when focused at infinity, it will only transmit the equivalent of f4(two stop loss) when focused such that something in sharp focus is the exact same size on the film as it is in real life(1:1 reproduction).

F-stops are used in photography because one f-stop represents the exact same(relative) amount of light regardless of the focal length of the lens in use.

[csxt30]

Here's my real hi-tech camera I've had since I was a kid. Can I still get film for it ? !!

Thanks, John

[lionelsoni]

Ben, you said that, "Considering both equation for F-stops and the short focal lengths of most digital camera lenses, you can see how it's possible to still have a tiny lens on a digital camera that still lets in a lot of light."  But, as you make the lens diameter smaller, keeping the field of view, the focal length, and the image size the same, you lose light in proportion to the square of the lens diameter.  In fact, for any particular field of view and resolution, the light available for each pixel is proportional to the square of lens diameter, however realized with respect to sensor size and focal length.

Astronomers use long focal lengths because they're working with big mirrors, not the other way around.  In fact, it is perfectly easy to make a small mirror with an arbitrarily long focal length.  The long focal length of a big mirror makes no difference in an image seen through an proportionately long-focal-length eyepiece (or instrument).  There is no practical reason for resolution better than the 1-arc-second ballpark for a conventional terrestrial telescope, which is about the best "seeing" that can be hoped for; so magnification of the image is not a goal.

[jimhaleyscomet]

As usual lionelsoni is right on the mark. 

The reason for longer focal ratio's in telescopes is to bend the light less.   The more you bend the light (ie the shorter the focal lenght) the better your optics and focus need to be.  Longer focal lenghts are more forgiving to lense and focus imperfections. 

There is a saying in astronomy  "Aperture Rules" .  You want the biggest lense and the longest focal length (ie focal ratio) you can afford, handle, and transport.    The same applies to cameras.  It is just portability is much more important and only recently have cameras regressed to such small lenses that light gathering suffers.

Can a small lense with great sensor do better than a poor large lense with a lousy sensor....yes.  However, all things being equal you want the largest lense that is convenient to use and is affordable to you.   To my daughter that is a tiny lense in a credit card camera....to me it is a larger lense in a palm sized camera...to a sports or bird photographer it is a huge lense on a monopod....to an astronomer it is a large lense (4" - 20" for amatures, 48" on the Hubble and up to 200" diameter for professionals on the earths surface).

Jim H  

[daan]

I've bought a simple and sturdy camera that fits in a pocket. Simply because everyone has to be able to use it and it shouldn't give too much problems using it. Even then there was a huge amount to choose from. Next I went to some photoshops and asked a few testpics of the camera's I wanted to know better. Luckily the person selling the stuff worked previously as salesman for one of the bigger companies.

About all pocket camera's are technically equal as far as hardware goes. Even the really cheap ones have rather good lenses and sensors, but the ones more expensive work with a library of settings. A professional photographer made with the exact same hardware photo's of (up to 900) different light, atmospheric and distantial subjects, picked the perfect ones out and stored the settings of them on a chip. When you make a picture, and everything is on automatic, the camera compares your image with the library and uses the settings in it to make the picture. It automatically flashes if that gives a better result. For a small, lightweight pocketcamera 10x optical zoom is rubbish. Even with 3x optical zoom you need a tripod to keep the photo sharp, simply because it's lightweight and small.

I normally shut off the automatic pilot, because I'm used to do it the oldfashionned way, but the camera itself, without me interferring, makes much better pictures.

Eventually I choose the Rollei da5324, with 5 meg. pixel and 3x optical zoom because it's built more sturdy then the others and because it takes normal AA batteries, so you don't have to stop photographing when the battery is empty. Every shop has new ones.

It has been on holiday in a bag on the back of the motorbike, my daughter even took it with her to school (without permission, so she was grounded..) it has been in the dashboard of a car in hot sunny day's etc, but it workes great and spits out very nice images/ films with sound.

[lionelsoni]

This is getting pretty far from trains; but here is a little story about a big telescope.  Years ago, I did a lot of work at McDonald Observatory, when their 107-inch telescope was new.  One night, a new employe went postal and tried to destroy the mirror.  He hit it a few times with a sledge hammer and fired a few bullets at it, but grossly overestimated its fragility.  I saw it the next day.  Afterword, the astronomers simply cleaned out and ground smooth all the fractured glass, resilvered the mirror, and painted the damaged areas flat black.  Compared to the total mirror area, the ruined part was tiny and has made no detectable difference in the telescope's performance, even though it's right near the middle of the mirror.

[jimhaleyscomet]

I have a tiny observatory on my Christmas layout.  It has a red light inside (Ctype christmas bulb).    There...that  ties astronomy to the toy trains on this forum....Oh...this post is about cameras and trains...Oh well...I tried.  ;-)

Jim H