Monday, January 16, 2012

What Camera Should I Get? (Basic)


If you're a beginning photographer or a nonphotographer and you're wondering what camera you should get, then this blogpost is for you.

First of all, I'm not going to say, "The best camera is the Canikon Ultra 2000EX Pro" or some other camera model.  Camera technology keeps evolving and the best model for you will change over time.  Besides, everyone has particular needs (e.g. camera size, budget, etc.) that makes it impossible to make any single camera the best one for everyone.  Instead, I would rather show you HOW to figure out what's the best camera for YOU.

More after the jump.



INTRO: HOW A CAMERA WORKS
Before we get to the answer, we need a crash course in how a camera works.  Basically, to record a picture, the camera has a hole that lets light shine on a sensor.  The recorded light becomes the image.

There are three things that a camera needs to adjust to record the image properly: how large the hole is ("aperture"), how long the sensor stays exposed to the light ("shutter speed") and how sensitive the sensor is ("sensitivity"):
- Aperture is indicated by the "f-number" such as f/2.8 or f/5.6.  The LOWER the f-number the WIDER the aperture.
- Shutter speed is usually shown as a fraction of seconds like 1/60 or 1/125 sec.
- Sensitivity is usually measured by "ISO".  Higher ISO means higher sensitivity.  Unlike film, digital cameras have changeable ISO.
The three variables work together.  You can widen the aperture and use a proportionately slower shutter speed.  You can increase the sensitivity and use a smaller aperture.  You get the idea.

HOW TO GET CLEARER PICTURES
The most common quality that people ask for in a camera is clearer pictures.  Here's the tricky part: blur can be caused several ways.
1. The subject could be moving too much.  The solution is a faster shutter speed.
2. You might not be holding the camera steadily.  The solutions are a faster shutter speed, and/or a tripod, and/or "stabilization" (the camera will move the sensor or the lens to counteract camera shake).
3. The sensor might have poor quality.  If the sensor sucks, the image is not going to be very clear no matter what.  To illustrate this, compare the pictures from a cheap webcam, old cellphone, or sub-$50 camera vs. a picture from a "normal" digital camera.
4. The subject could be out of focus.  You can tell that this is the issue when part of the image is clear (just might not be the part you wanted).  In cameras these days, this is usually not the issue except for occasional mis-focusing.
5. The lens might have poor quality.  As with the sensor, if the lens is poor quality, the image won't be clear.  In the real world though, any half-decent camera will have a reasonably functional lens.  So this is not likely to be the issue.

QUALITIES OF A GOOD CAMERA
Although there are many causes of an unclear image, the good news is that you need to look for a few things in a camera to address all those issues:

A. Good sensor.  When a camera increases its sensitivity, the image will have more "noise."  A noisy image looks very grainy and/or there are colored splotches on the image, especially in the shadows.

A picture with lots of noise. Click and zoom in to see the grain.
Camera makers have a way of "fixing" noise.  It's called noise reduction which removes the appearance of noise but sacrifices detail.  When the noise reduction is very strong, the image looks blurry, like it was painted with water color.
An image with high noise reduction resulting in some loss of fine details and texture.  Click to zoom in.
A good sensor can increase sensitivity without having too much noise (and won't need very high noise reduction).  When a camera can have high sensitivity with low noise, you can shoot with a high shutter speed, addressing issues 1, 2 and 3 at the same time.

Please note that just because a camera has a high sensitivity setting doesn't mean it necessarily has low noise.  There are some compact cameras that tout sensitivity as high as 6400 but look like crap at that ISO, so it's not useful.

To find cameras with good sensors, check out many sites that show high ISO comparisons of cameras such as DPReview.com. Or google "high ISO" with the camera you're investigating.  The difference between sensors usually becomes very visible at ISO 1600 and above.  Another way to compare is to see the size of the sensor.  Generally, larger sensors have less noise than smaller sensors, although new small sensors can have less noise than a larger but older sensor.  And if YOU can't tell the difference then don't sweat it - no matter what the review says.

B. Stabilization.
Stabilization can solve issue #2 above.  With stabilization, a camera will try to counteract the camera shake by moving the lens and/or the sensor.  Some cameras have effective stabilization while others don't.  Some cameras have no stabilization at all.  Others will claim to have stabilization but actually do nothing but increase sensitivity (to raise shutter speed so as to make camera shake less noticeable).  See http://www.dpreview.com/news/2007/1/5/notimagestabilization .

To find out the effectiveness of a camera's stabilization, read reviews from sites such as DPReview.com.  They will usually comment on how effective the stabilization is.

C. Wide aperture.
The wider the aperture available, the higher your shutter speed can be.  This can solve issues #1 and 2.

The aperture of lenses is not unlimited.  Lenses have a maximum aperture that will be shown in the specifications.  You'll often see a number like f/3.5-5.6 or 1:3.5-5.6.  That means the lens' widest aperture changes as you zoom in.  The first aperture (3.5) is the aperture when the lens is at its widest.  The second aperture (5.6) is the aperture when the lens is at its longest.  I would pay attention to both numbers and probably give greater weight to the second number.  In other words, I much prefer a camera that has an aperture range of f/2.0-3.3 over another that has f/1.8-4.9.

What about lens quality?  Fortunately, camera manufacturers know their market pretty well.  They know that any buyer who is looking for a good sensor will be particular about the lens quality.  So all cameras with good sensors have decent if not good lenses.  If you want to be particular about it, you can see reviews to compare resolution, contrast, color, distortion, chromatic aberration and other lens characteristics.

IF YOU WANT TO LEARN PHOTOGRAPHY
In addition to the foregoing factors that have the most direct impact on image quality, there are other features that you may want in a camera if you plan to learn photography, even though you might not think they're useful now.

D. Manual controls.  If you really want to learn photography, look for a camera with the four primary exposure modes (PASM), PSM, or at least Manual mode.  However, not everyone is willing to take the time to learn photography and in my view, it is possible to get good pictures even with fully automatic controls.

E. Wide angle.  A wide angle is useful for capturing more of a scene or for shooting subjects in smaller spaces.  In terms of composition, a wide angle has a unique look that cannot be easily simulated (except by stitching several shots).  In this regard, many compact cameras have the not-so-wide equivalent of only 35mm or so.  True wide angle would be 28mm or wider.

24mm equivalent

F. Hot shoe.  A very important aspect of photos is lighting.  In that regard, having a hot shoe allows you to use external flashes which give you many more options for controlling lighting.  Good flash technique can also address issues 1, 2 and 3.  Almost all cameras use a "standard" hot shoe, which makes many flashes partially interchangeable.  The exceptions are Sony and the Nikon 1 series which have their own kind of hot shoe.  If you don't plan to learn photography, you don't need a hot shoe.

G. Raw mode.  Another important aspect of photography is postprocessing (editing the photo after it's taken).  To have the most options for changing the image during postprocessing, you need raw mode, which means means the camera can give you an uncompressed and unprocessed image file instead of a picture file that has already been processed according to what the manufacturer thinks.

There are other factors that determine quality of a camera such as its dynamic range or whether it has certain features that are important to photographers.  But those are the basics.

CONTROLS
Before buying a camera, I also suggest handling it to see if you like the controls, menus and ergonomics.  For some people, this can be the deciding factor.

MISSING THE SHOT
I should mention that the other most commonly requested feature is a camera that can "shoot quickly."  They usually complain that they are trying to take a photo of their kid or pet but the camera takes too long to capture the shot, thus missing the photo opportunity.

Comments:
- There's a unique camera out never needs to focus yet will always take perfectly focused shots (in fact you can change the focus *after* the photo has been taken). But it's not cheap and has many limitations.  Lytro $399.
- Next fastest-focusing option: DSLR.  Most DSLRs can focus faster than compact cameras.  There are exceptions (a few DSLRs are slow to focus) and focusing speed is affected not just by the camera but by the kind of lens.  See below: "Should I buy a DSLR?"

For most people, though, the best answer to capturing the moment (other than avoiding cameras known to have slow autofocus) is through shooting technique.  Specifically, by pre-focusing and anticipating the moment.  Reducing "Shutter Lag."

QUALITIES THAT ARE NOT IMPORTANT
- Megapixels.  More megapixels doesn't mean that the sensor is better.  It's much more important to have a sensor with less noise.  Unless you plan to print huge posters, anything that has 6 megapixels is more than enough.  Moreover, having too many megapixels usually means a sensor with higher noise.
- Digital zoom.  Digital zoom doesn't mean anything more than the camera cropping the middle of the photo to make it appear larger. Digital zoom doesn't offer any additional detail and you can do it yourself in a computer.
- Very long lens.  Manufacturers sometimes make a big deal about their camera having a very long lens (let's say over 300mm). However, for most people, there are only a few situations that require a very long lens, such as bird photography, animals, or stadium sports.  Even then, you would need a tripod to hold the camera steady.  For most people, it's not practical.  Another thing to note is that when the lens is fully zoomed in, the aperture is usually very small (thus often forcing a slow shutter speed, which is ironic, given that animal and sports photos usually need high shutter speeds).

CURRENT EXAMPLES OF GOOD COMPACT CAMERAS THAT *MAY* BE RIGHT FOR YOU
As of December 2011, these are some compact cameras that in my opinion meet the needs of many family photographers:
  • Fuji X10 - has all of the foregoing.  Much more than what most casual photographers need but if you have the cash...
  • Canon S90, S95, or S100 - has all of the foregoing except a hotshoe.
  • Panasonic Lumix LX-5 - has all of the foregoing. Reviewed here.
  • Nikon P300 - has all of the foregoing except a wide aperture, hot shoe, and raw mode.  Reviewed here.
If you don't need a camera that is so compact, you might consider moving up to a mirrorless or DSLR.  See below.

SHOULD I GET A DSLR or MIRRORLESS CAMERA?
Almost all DSLRs and mirrorless cameras have superior image quality compared to compact cameras.  99% of the time, a photo with one of these larger cameras will look better (less noisy, more detail) than a photo with a compact camera taken under the exact same circumstances simply because these larger cameras have larger sensors and more specialized lenses (rather than a lens that tries to do it all, and at low cost).  Moreover, these cameras have controls that a budding photographer can grow into.

It goes without saying that when you're getting one of these interchangeable lens cameras, the image quality will also depend on the quality of the lens you choose.  I hate to say it but when it comes to lenses you generally get what you pay for.

I should also caution you that getting an interchangeable lens camera will not necessarily guarantee that your photos will actually look good.  That's because...

FINAL REMARKS
...I'll let you in on a secret: none of this really matters.  If what you care about is having good photos, the way to get that is through learning photography techniques. Start with good composition and lighting.  When you get decent at that, I suggest learning post-processing.  If you have at least a decent (even if not great) camera, learning photography will have a greater impact on your photos than buying a high quality camera.

RELATED POSTS:
Simplified Guide to Exposure
Roadmap for Family Photographers
Basics of Lighting
Should I Buy a DSLR?