1. Leaving the lens cap on
Amateurs are guilty of making some of the most cardinal of mistakes. Although, we do tend to blame amateurs but professional are also guilty of the same mistakes from time to time. Call it oversight or just plain callousness, but leaving the lens cap on and then wondering why the viewfinder is so dark is something that we are all guilty of at one point of time or other. To overcome this issue, I have personally made it a point to look at the front of the lens before beginning every new photo session. This is just to ensure that I am not guilty of having left the lens cap on. It saves me from the blushes and the missed photo opportunities.
2. Switching to monochrome and then forgetting to switch back on
Black and white photos are able to capture the essence of a scene without the distracting colors. When you take away the colors all you are left with is the inherent beauty of a subject or a story that slowly unfurls in front of the viewer. Monochrome photos appear somewhat dark and mysterious, but if done rightly they also tend to result in breathtaking compositions. Beginners often are inspired to experiment with monochrome compositions. But after having experimented with shades of grey and black they forget to change back to normal color. The result is unintentional monochrome images when color should have been the better option.
3. Using the exposure compensation option and forgetting to reset it afterwards
The exposure compensation button is a really helpful control. It is an override of sorts for the priority and programmed auto modes. In some sense it is like using your DSLR in the manual mode without actually changing to manual. Regardless of the reason for you to use exposure compensation you will need to remember to switch back when you are done. Depending on the amount of exposure compensation used, if you do not revert back, it will continue to affect all your images from thereon. Depending on whether you have used positive exposure compensation or negative exposure compensation, you will end up with all your images either over-exposed or under-exposed. Sure you can correct the affects in Lightroom or Photoshop, but at times this may extend your post processing workflow by a considerable extent.
4. Forgetting to download the images and getting stuck with a full memory card
Make it a habit to download all your images on to your computer hard drive after you conclude shooting for the day. A simple folder structure could be year > month > day or year > month > event_day. I use the second to ensure that my images are never out of place and also so that I can locate an image when I need it in a jiffy. An additional advantage is that when I arrive at an event, I am never stuck with a memory card full of images that I have not yet downloaded.
5. Selecting a big ISO number for shooting in darker conditions and then forgetting to change back, or vice versa
ISO is a measure of the sensitivity of the sensor to light. It is expressed as a number. Higher the number, higher is the sensitivity and vice versa. Usually when shooting in low light conditions, a photographer would use a higher ISO number to increase the sensitivity to light and thereby make a proper exposure. When shooting in broad daylight that same higher ISO will, however, create an over-exposed image. Amateurs often make this mistake. They forget to revert back and thereby lose photo opportunities. The best way to handle this is to check for the ISO settings at the start of a new photo session.
6. Choosing the incorrect focus mode
Focusing modes denote which focusing option you have selected. There are three focusing modes available in most digital SLR cameras. They are AF-A or auto-servo AF, AF-S or single-servo AF and AF-C or continuous Servo-AF. AF-S is the ideal auto focusing mode when you are shooting a stationary subject. AF-C is ideal for a subject that is moving around and AF-A is the option which you should go for when you are not sure whether to go for AF-S or AF-C. In this mode the camera decides the AF mode. This extended explanation was necessary because as a beginner most are guilty of selecting the incorrect AF mode. Sometimes this is due to pure ignorance and at other times due to laziness. This results in poor AF performance and blurry images. Let’s say you are shooting a kid playing in the yard. The ideal AF mode is AF-C. In this mode when the subject moves from one area of the frame to the other the corresponding AF point overlapping that area acquires focus. The subject, as a result is never out of focus. If you select AF-S, and if the subject moves after focus is locked, you will need to re-acquire focus. Otherwise the subject is out of focus.
7. Selecting shutter-delay mode and then forgetting to change it back
This is a classic example of forgetfulness. If it makes any better I have, myself, been guilty of this on a number of occasions. Shutter delay mode is primarily used for group shots. Which is absolutely fine. Except, when you forget to revert back. I remember having set my camera on a ten second delay so that I could run and fit myself in a group as well as have the time to pick up my daughter. It was a hit. The embarrassment was when I forgot to revert back while shooting a portrait image. Imagine my predicament when I clicked the shutter and realizing my mistake had to keep pretending that I am still composing until the shot was finally taken!
Most of the above mistakes can be avoided by checking your equipment before leaving home and taking a couple of test shots upon arriving at the venue and before starting the main shoot.