Lowyat.NET: Latest topics by ebernie

What's a benefit of a constant aperture lens?

ebernie — Tue, 15 Apr 2008 00:03:25 +0800

I'm interested as to why constant aperture lenses are so sought after? Thoughts please

UPDATE: The purpose of this thread is to thrash out ideas as to what the benefit of having a constant aperture in a zoom lens. Now obviously it's more expensive to manufacture a constant aperture lens so why the need? Surely Canon/Nikon/Olympus/Sony cannot be churning these out for no reason. Even if they did, people wouldn't buy them.

Also, keep in mind that though a constant f2.8 is always thought of the only constant aperture lenses have, this is not true. There are zooms that have constant f4 throughout its zoom, usually very long telephotos used for birding.

If indeed faster lens is better and constant aperture lenses are more expensive, surely it's better to have a 80-400mm f3.5-f5.6 compared to a 80-400mm f4 because at least you get f3.5 at the widest angle.

But instead the manufacturers released a very pricey 80-400mm f4.

After seeing the thread grow to 3 pages without much progress, I wish to share my thoughts on this.

IMHO, shooting in manual exposure mode will shed light on why constant aperture lens is always better than a variable one. And this is generally agreed to be the benefit of having a constant aperture - a constant aperture will allow you to keep exposure constant throughout the zoom range.

It is as simple as that. Yes, you can adjust shutter to compensate for brightness. You can also fool around with ISO. In fact, you need to do this every time you change focal length on a variable aperture zoom. This is time consuming and error prone resulting in the frequent zoom - adjust - zoom - adjust cycle.

If you shoot in the one of the PAS/scene modes, the camera adjusts the settings for you but you open yourself up to the mercy of the camera which can result in camera shake (too low a shutter) and exposure errors (metering issues). But again the problem is inconsistency.

Thanks to all the seniors which participated in the discussion. I hope the newer folks entering the realm of DSLRs will come across this thread in the future and that it will help them answer this nagging question

Also the f-number is derived from the (focal length) / (size of the diameter of the lens opening).

Nikon buy over Canon, EOS is no more

ebernie — Tue, 01 Apr 2008 15:56:43 +0800

As reported by Fox News.
http://www.fox-news.com.nikon-buys-canon.n...Buys-Canon.html

Eat your heart out Canon fan boys! EOS is scrapped liau. Total cost 34.2 million.

Photog classes / courses

ebernie — Tue, 05 Feb 2008 00:48:58 +0800

So, what say you?

I've never been to a class officially, just a free workshop conducted by Nikonian Academy. They offer other more advanced classes though. Since three to four hundred ringgit is no small amount, I would like to ask the opinions here.

If you've attended before, do share the experience and opinion.

If you're against classes, why?

Rules of thirds

ebernie — Tue, 22 Jan 2008 02:11:55 +0800

For the uninitiated, the rule of thirds is simply placing your pictures in certain locations in your frame. To determine the location, break up your frame into a tic-tac-toe puzzle and place the subject photographed at any of the intersections

CODE

| |
| |
| |
----------------------------------------------
| |
| |
| |
----------------------------------------------
| |
| |
| |

Simple rule, no? But like all rules, sometimes they are meant to be broken. The question is, when? Any tips? One I've heard is that when photographing common subjects (your mum, bicycle, pencil), it is better to adhere to the rule. But when photographing subjects which gives a large impact by itself, do those head-on, centered and fill up the frame (beautiful model, old wrinkled face, etc). Sorry but no sample pictures but hope it's understood. I kinda like this exception to the rule and have seen sample pictures.

Any other exceptions to the rule?

Fast (f2.8 & below) potrait lens for D40

ebernie — Thu, 17 Jan 2008 13:54:12 +0800

Any suggestions?