Readers' Questions

Hi Steve,
You could add in a question to the fireworks photo basically as an amateur photographer, what settings would I use to get the best results with fireworks at night?
Regards,
Gary

 

Fireworks are always fun.  Most compact point and shoot cameras have “picture modes” built into their programming and these picture modes almost always include a “fireworks” mode.  Give this a try and see if the results improve?

If you don’t have a fireworks mode and you use a regular automatic mode, what you’ll end up with is a overexposed image with blurry fireworks.  I recommend a tripod, beanbag, or other steady support and adjusting your settings as follows.

  1. ISO.  Set this to the highest settings where you can accept the noise.  On a DSLR ISO 1600 will give great results with fireworks.
  2. Aperture.  With fireworks you don’t need to be concerned with depth of field (DOF) because the fireworks are so far way.  Choose the widest aperture that normally provides good results, say F4 for instance.  This will allow the minimum shutter speed.
  3. Now, frame your scene and adjust your shutter speed so the sky is dark (vs. an overexposed orangish color), and the fireworks are properly exposed.  You’ll find you can use a pretty short shutter speed and capture great images of the fireworks suspended.  You can also ‘drag’ your shutter and catch the fireworks falling and blurring together, but be sure your camera is will supported so your entire image isn’t blurry.
  4. Auto White Balance is usually sufficient for fireworks, but if on your LCD you see colors that you don’t agree with, adjust your white balance until the colors are as close  to real as possible.

I hope this helps.  I’ll be taking some sample firework pictures next time we have them here and I’ll share those with more instructions in the future.

Hi BKKSteve,

I was meant to post this question way back when you covered ASA/ISO, but now you have already done shutter and aperture!!

Anyway, not bothered if this gets posted or not, just want to dip my toe into your font of photography knowledge (FPK).

ASA indicates the sensitivity of a particular film to light - understood.

ISO is the same thing for digital cameras.

Herein lays my quandary.  We do not have film in a digital camera, only a sensor of some description.  Therefore, why do we not only have shutter and aperture to worry about and not ISO?  Basically, what does the ISO on a digital camera relate to?

Many thanks, keep up the good work, it's a great addition to Stick's site.

Shaun

Shaun –

Nice to hear from you.
Thanks for the question.  I’ll answer it here and in next Saturday's weekly because if you have this question I’m sure others do as well and could benefit from the answer.

Film has the ASA value and as you know we’d buy different emulsions of film with a different sensitivity to light.  25-6400 ASA was commonly available.

Sensors of course aren’t changed out like film, there is only one sensor in a given digital camera yet it has an ISO “range” that might be from 50-12,800 or more in the newest digital cameras.  You’re asking “what does the ISO on a digital camera relate to?” and since I’ve already said in the column that you can equate ASA to ISO values directly between film and digital cameras, you must be wondering what changes with the sensor since it’s the same sensor, while with film we’re putting in completely different films to achieve different ASA’s?

Think of the sensor in a digital camera has an stereo amplifier.  It has a volume knob where you can adjust the volume to a range of settings which takes the input from your CD player (think of this as light into your camera) and amplifies it through a range of adjustment (think of this as the range of available ISO values), producing a different level of sound from your speakers (think of this as the image on your computer monitor).  At the lower settings the sound will be most smooth and pure and free from distortion, but as you crank up that stereo to higher volumes you induce clipping and other forms of distortion.  A digital camera sensor is capable of producing different levels of sensitivity to light (from the same sensor), however you sacrifice different levels of output quality.  In the case of digital camera sensors this would be detail, noise (like film grain), dynamic range, and more.

I hope this helps.

Steve

 

Please submit your questions to QandA@Bkkimages.com  All questions will be answered and most will show up in the weekly column.