Is there a big difference between f4 and f2 8?

The most obvious difference between an f/2.8 and an f/4 lens is in their “brightness”, i.e. in the maximum amount of light each lens allows to reach the sensor. An f/2.8 lens would usually be capable of giving a more shallow depth of field (and therefore a bigger background bokeh) than an f/4 lens.

Is f2 8 good enough?

If you have a fair bit of ambient light, a slow(ish) subject, IS and a camera with good high ISO image quality, then an f 2.8 lens will be adequate for almost all photos without flash.

What makes a lens more expensive?

Production Costs and Quality of Components – one of the main reasons for the high cost of professional lenses, is production costs and high quality standards set by the manufacturer. Consumer-grade lenses are manufactured in batches in a mostly automated fashion with very little human involvement.

Is f4 OK for portraits?

f4 would be OK depending on your subject to background distance (you might want to frame your subject relatively tight and make sure you have a good distance between your subject and background). 2.8 would be a bit better though for portrait work.

Is F4 fast?

f/4 is not considered a fast lens. Since you shoot indoors, and low light, the 2.8 lens is a better choice for you. If you have top ISO performing DSLR, so f/4 could be good enough for you.

Is F4 enough for astrophotography?

Focusing the lens is a straight forward process at 24mm, and even offers a little forgiveness at an aperture of F/4. Faster lenses that can open up to F/1.8 are beneficial for astrophotography but often result in a challenging focus routine.

Are expensive lenses worth it?

In most all cases, an expensive lens is better by a great deal. That cheaper, entry level lens, by contrast, may not be all that much slower, but it will have cheaper glass, and more plastic pieces to save money and weight. A cheaper lens doesn’t necessarily mean it won’t work for your purposes, it likely will.