Apature

[achuang]

The simplest way to prove your crazy theory to us Razr, would be to take a photo with a variable aperture lens (say f3.5-5.6) and take it at the telephoto end of the zoom and post the photo with exif intact and then you can show us how wrong the whole world is. If you're right then the aperture will be f3.5 even at the telephoto end of the zoom.

[Rooz]

i asked him to do that 6 pages ago. he won;t cos he doesn;t have a camera.

[achuang]

i asked him to do that 6 pages ago. he won;t cos he doesn;t have a camera.

I see, well that's unfortunate. Where's the fun in that? I was looking forward to being able to shoot my 55-200 lens at f4 all the way until 200mm.

[pas49ras]

Only if you are in "P" (PROGRAM) or "A" (AUTOMATIC) modes.
The aperture stays the same in "Av" and "M" (MANUAL) mode, no matter what focal length you choose, making any f/2.8-f4.5 etc. lens a "fast"-constant apeture lens throughout the zoom range.

This is the dreaded misconseption that started all the discussion...I have shot thousands of pictures in AV mode with a variable aperture zoom lens and as you zoom out the lens stops down..the aperture gets smaller. Its just the way that a lens is made. It would happen in any mode..AV mode just lets you select a aperture from the camera body, it can't (and will not) lock the aperture. The thing that is changing the aperture is the turning of the zoom ring.

[tim11]

Why would anyone pay more for Sigma 18-50 F/2.8 (me included) if one can just use Sigma 17-70 F/2.8-4.5 and 'lock' it at F/2.8 throughout the zoom range?
Maybe they don't know how to use A or M modes? LOL.
I can't wait to see what 'thesis' he will come up tomorrow morning and prove it's all possible.

[SpecialK]

I've already asked Jeff to close this thread about 4 pages back. I hope he will.

I suggest 2 things:

1. No one post another comment in this thread. We are wasting our time with someone who will never learn, nor wants to.

2. No one ever respond to RAZR in any other thread - ever.

Do not reply. Ever!

[r3g]

I suggest 2 things:

1. No one post another comment in this thread. We are wasting our time with someone who will never learn, nor wants to.

2. No one ever respond to RAZR in any other thread - ever.

Do not reply. Ever!

Oh your taking all the fun out of the internet.. Get real!

[fionndruinne]

That's right r3g!

It's funny how he seems to think there's a magic way of getting large-apertures out of variable-aperture lenses... as if no one else had figured out such an important concept, and weren't all using their 17-70mm f/2.8-4.5's for kicker cheap macro lenses at 70mm f/2.8.

It's true, though, the insults have gotten out of hand. Calling Razr all sorts of (apt) names isn't going to make him listen up.

But it's certainly been a chuckle or three. Makes little ol' DSLR-newcomer me feel all knowledgeable.

[Razr]

NO. YOU ARE WRONG. At full zoom of the lens in question (ie. sigma 17-70 f/2.8-4.5) only F/4.5 is available.

You are a bigger idiot than I previously thought you were since you keep denying you are wrong.

I'll report you for your insult.

[TheObiJuan]

I've already asked Jeff to close this thread about 4 pages back. I hope he will.

I suggest 2 things:

1. No one post another comment in this thread. We are wasting our time with someone who will never learn, nor wants to.

2. No one ever respond to RAZR in any other thread - ever.

Do not reply. Ever!

I blocked him a while ago and then was excited to hear Razr was banned, apparently it was a temporary ban. He needs to be PERMANENTLY BANNED.

He is a troll--no doubt about it.

BTW, it's good to know that my Sigma 70-300 f/4-5.6 is really a 70-300 f/4 in Av mode!
Whoopee, who needs a Sigma 100-300 f/4 when I can have a Razr version of the 70-300 with f/4 for 1/4 the cost!!