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kd_1014 wrote: ↑

Tue Oct 20, 2020 11:05 am

You want it to blur? If you do, the SS will be 1/30 or lower. To create a long blur when it's dark, you can set up a long exposure with a tripod with the SS set to 1 second to up to 30 seconds. The ISO will be set higher and higher depending on how dark it is. Aputure also will be better if it's wide open. 1/30 creates a blur in daytime and might be over exposed a bit but after editing it'll be just fine.

kd_1014 wrote: ↑

Tue Oct 20, 2020 12:32 pm

I haven't really figured out how to get a sharp picture without it being very grainy. I'll follow this thread for advice as well

GTWChris wrote: ↑

Tue Oct 20, 2020 8:58 pm

The short answer is you need a faster lens with a wider maximum aperture (lower f stop) that allows more light into the camera.

Three variables that affect image exposure: aperture, shutter speed, and ISO (film speed, sensor sensitivity). A wider aperture, slower shutter speed, and higher ISO all allow for a greater amount of light to penetrate the sensor, all of which you'd want in lower light. However, changing each of these has trade offs. A wider aperture decreases depth of field, a slower shutter speed can create a blur, and a higher ISO becomes grainy.

Since you want to stop motion and do not want a grainy image, you're left with increasing the aperture. You'll want to choose a shutter speed sufficient enough to stop the motion, an ISO that is not too grainy, and the maximum aperture that your lens allows.

Not all lens are created equal with regard to aperture. In order to stop motion in poor light conditions you'll want a faster lens with a very wide (lower f stop) aperture. Generally, the faster a lens the more expensive it will cost. The basic "kit" lenses that come with entry level DSLRs are typically slower lenses with relatively poor maximum apertures. For example, Nikon's basic 18-55mm lens has a maximum aperture of f3.5 (which is really not a full aperture stop but no need to get into that). For comparison, Nikon makes a 50mm f1.4 lens which is almost a full 3 stops faster than the basic kit lens. You'll notice a huge difference in lower light conditions using a lens that is 3 stops faster.

A prime lens (those that have a fixed focal point and are not zoom) are typically going to get you a faster lens than a zoom lens. My recommendation if you want a good lens for lower light is to buy a 35mm or 50mm F1.4 or F1.8 lens. These are all in the $200-$500 range new. On a half frame camera, a 35mm lens is more or less equivalent to a normal lens which yields a similar perspective to human vision.

If you use a DX Nikon, I would personally recommend the AF-S DX NIKKOR 35mm f/1.8G. It's a phenomenal lens and excellent in low light situations. New these go for $200, but there are plenty of used ones around and you can pick one up for around $100 used.

Hopefully this helps. I'm not sure how much you already know about cameras so I tried to provide a high level overview, but I'm happy to go into more detail.