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In the spirit of the gallery here that the moderator has worked so hard to organize, I prefaced this post with Camera Tips... as opposed to VIDEO Tips or something else....
Terms
Shutter Speed. The faster the shutter speed the more likely you are to 'stop motion' or 'freeze' the image. This is a good thing if you want a clear image of your rocket. Of course if you want a blurred effect then that is a different story. Lower speeds let in more light, higher speeds let in less light. So 1/250th of a second is seems fast, but 1/1250th or better is desired for freezing a rocket in flight.
Aperture Almost all cameras have a variable opening in the lens or in the light path. There are subtleties I won't get in to, but for now. The bigger the opening the more light gets in. Smaller the opening the less light gets it. A side effect is the bigger the opening the smaller the range where things are in focus. This is known as Depth of Field. Aperture looks like f/2, f/4, f/5.6, f/8, f/10, f/13 etc... larger numbers equal smaller openings which means less light, more depth of field (more range of stuff in focus). Also with zoom lens so prevalent, high apertures tend to take sharper pictures, lower apertures not as much. Lens are a compromise. The less compromise, the higher the cost. Most consumer lens/cameras are at their best at f/5.6 and above.
ISO Back in the old days film chemistry was altered to make certain films more sensitive to light in varying degrees. So ISO 100 film was not as sensitive to light as ISO 400. So if you were shooting in low light, ISO 400 was preferable as it was more sensitive (I am being simplistic here). The trade off was ISO 100 gave better looking photos than ISO 400. In modern digital cameras the terminology is the same AND the result is the same. All that is different is we are turning up the gain (amplification) on the digital chip instead of changing the chemistry. We still have the trade off on image quality (to varying degrees depending on $$$$ spent). High ISO has more digital noise than lower ISOs. (chip size and makeup play a role here as well - but lets leave that out)
Focal Length
For now, and for simplicity sake, lets just say focal length is what you are changing when you zoom in or out (if your camera has a lens that moves - internally or externally). Not digital zoom. That is something else. I am referring to moving optical components in the lens. Generally the more you zoom, the high the Aperture number goes (unless you spend $$$$), so the less light you get, the more shake you get, and the narrower the area the lens covers (called Field of View). Nothing wrong with zoom, you just need to balance it with everything else.
For rocketry I try and MAKE the camera optimize a high shutter speed and small aperture. That way I freeze the motion (high shutter speed) and maximize the amount of range that is in focus (higher aperture). Obviously to do that I need a lot of light. Normally getting enough light is not an issue as it's daylight. If the amount of light IS an issue, I try to raise the ISO rather than open up the aperture. That way I keep my fast shutter, wide range of in focus area in return for somewhat worse image quality (noise).
How we MAKE the camera do that is a subject for another post....
Comments?? Thoughts? Additions?
One last item... you can mitigate a lot of what I said were 'trade-offs' by buying high end DSLR cameras and high end lenses. But you still have to know WHAT to do with them.
Terms
Shutter Speed. The faster the shutter speed the more likely you are to 'stop motion' or 'freeze' the image. This is a good thing if you want a clear image of your rocket. Of course if you want a blurred effect then that is a different story. Lower speeds let in more light, higher speeds let in less light. So 1/250th of a second is seems fast, but 1/1250th or better is desired for freezing a rocket in flight.
Aperture Almost all cameras have a variable opening in the lens or in the light path. There are subtleties I won't get in to, but for now. The bigger the opening the more light gets in. Smaller the opening the less light gets it. A side effect is the bigger the opening the smaller the range where things are in focus. This is known as Depth of Field. Aperture looks like f/2, f/4, f/5.6, f/8, f/10, f/13 etc... larger numbers equal smaller openings which means less light, more depth of field (more range of stuff in focus). Also with zoom lens so prevalent, high apertures tend to take sharper pictures, lower apertures not as much. Lens are a compromise. The less compromise, the higher the cost. Most consumer lens/cameras are at their best at f/5.6 and above.
ISO Back in the old days film chemistry was altered to make certain films more sensitive to light in varying degrees. So ISO 100 film was not as sensitive to light as ISO 400. So if you were shooting in low light, ISO 400 was preferable as it was more sensitive (I am being simplistic here). The trade off was ISO 100 gave better looking photos than ISO 400. In modern digital cameras the terminology is the same AND the result is the same. All that is different is we are turning up the gain (amplification) on the digital chip instead of changing the chemistry. We still have the trade off on image quality (to varying degrees depending on $$$$ spent). High ISO has more digital noise than lower ISOs. (chip size and makeup play a role here as well - but lets leave that out)
Focal Length
For now, and for simplicity sake, lets just say focal length is what you are changing when you zoom in or out (if your camera has a lens that moves - internally or externally). Not digital zoom. That is something else. I am referring to moving optical components in the lens. Generally the more you zoom, the high the Aperture number goes (unless you spend $$$$), so the less light you get, the more shake you get, and the narrower the area the lens covers (called Field of View). Nothing wrong with zoom, you just need to balance it with everything else.
For rocketry I try and MAKE the camera optimize a high shutter speed and small aperture. That way I freeze the motion (high shutter speed) and maximize the amount of range that is in focus (higher aperture). Obviously to do that I need a lot of light. Normally getting enough light is not an issue as it's daylight. If the amount of light IS an issue, I try to raise the ISO rather than open up the aperture. That way I keep my fast shutter, wide range of in focus area in return for somewhat worse image quality (noise).
How we MAKE the camera do that is a subject for another post....
Comments?? Thoughts? Additions?
One last item... you can mitigate a lot of what I said were 'trade-offs' by buying high end DSLR cameras and high end lenses. But you still have to know WHAT to do with them.
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