Why a D-SLR can give a better picture?
by hjfok - 4/16/09 6:27 PM
In Reply to: SLR vs Digital Compact by mKlipper
Thanks for all the comments. Let me apologize for a long answer, because I'm trying to answer the several responses above. I did not post a low light action photo from a PS camera because it simply cannot take a decent action photo in low light. I usually do not even try, but even if I do try, it usually end up blurry and I delete it right away from the camera. I don't save obviously bad photo to waste space in my memory card or computer.
The purpose of the comparison above is to illustrate a couple of points. One point is that one can absolutely take good photos with PS camera in the right conditions, and you may not notice much difference from a D-SLR. The second point is that there are however challenging low light conditions that can limit the use of PS cameras and may require the D-SLR (usually low light actions). Sorry I did not save bad low light action photos from a PS camera to illustrate the difference. I was trying to show what a D-SLR can do in low light actions (by the way, these are all done handheld and I am just an amateur taking family and travel photos, so practically anyone can do this or better with the right equipment).
Now regarding the question, why a D-SLR can do a better job in low light? The short answer is due to the larger sensor and better/faster lenses. The actual size of the apertures for D-SLR lenses are much bigger than the compacts. The prosumer models have larger lens but the sensors are still much smaller.
We can start with the basics. Photography is basically recording light reflected by the subjects and background. The recording is either done on film or converted to electronic signals on the sensor. The film has a photochemical reaction whereas the digital camera sensor has photodiodes that can react witht the photons and convert to electronic signals. We will focus the discussion on digital cameras. We are used to the nomenclature of pixels in digital camera. Each camera pixel has a photodiode (except the Fuji camera, there are 2 photodiodes per photosite and Fuji count them as 2 pixels per photosite). The bigger sensor has bigger photodiode whereas smaller sensor has smaller photodiode(higher pixel counts will also decrease photodiode size). The bigger photodiodes will give the D-SLR the advantage of better dynamic range (less blooming and clipping artifacts). The noise is also much lower in the larger sensors in D-SLR due to the electronic circuits are not as densely packed as the smaller sensors. As one can see the difference between CMOS vs CCD, CMOS generally has slightly lower noise due to less complicated circuitry.
In general, the shutter time or speed is adjusted to how much light is available (automatically or manually). The lower the light, the longer the exposure time, the slower the shutter speed, and the more chance you will get blurry action photo. Having larger lens openings is an advantage for D-SLR or DSLR sized prosumer cameras because more light/photons can reach the sensor, thus a faster shutter speed can be used and able to freeze action in lower light. And the D-SLR has the additional advantage of a larger sensors with better sensitivity and lower noise. This enables D-SLR to get decent quality photo as high ISO, thus faster shutter speed can be used compared to prosumer models. The better lens and faster lens speed and generally large lens diameter all contribute incremental advantage to D-SLR in low light actions.
So in conclusion, PS cameras and prosumer cameras are very capable cameras but they don't perform so well in low light condition. D-SLR still easily outperforms in low light action photos. You can still get a decent low light still picture with PS cameras but it is not as easy especially without a tripod. The photos above just illustrate what can be done with either types of cameras, but I can tell you it is much easier for me to use a D-SLR for any low light photos compared to a PS camera.
I don't mean that everyone should or need to get a D-SLR to fully enjoy photography. Photography is a very flexible hobby, you don't need to spend a lot of money to enjoy it. You just need to open up your eyes and use your imagination and creativity to make a great photo. You also need to know the limitations of your equipment and how to make the best use of what you have. I love my dog photo done from a 2MP PS camera as much as the low light actions photos from my much more expensive D-SLR and hefty tele lens. So pick your subject and focus point wisely and use your imagination to compensate for the lack of performance in equipment.
Was this reply helpful? (0) (0)