DPChallenge: A Digital Photography Contest You are not logged in. (log in or register) 
 

DPChallenge Forums >> Hardware and Software >> New Sigma 50-500 Lens, Now I gotta go out and play
Pages:  
Showing posts 1 - 9 of 9, (reverse)
AuthorThread
 11/05/2004 08:22:26 AM · #1
So far so good and within my budget $1050.00 Total including tax
Heres a shot or two of it... now I need(NEED) to go and play outside... ;)



Message edited by author 2004-11-05 08:22:46.
 11/05/2004 09:04:20 AM · #2
That's a hunk o'glass! You'll have to post some shots... I'd like to see something from both ends (50mm and 500mm). What is the minimum aperture range on that lens?
11/05/2004 09:18:02 AM · #3
I have the 170-500mm Sigma APO F5-6.3 and am very pleased with it. I think you may be having some fun with it.. bit slow for sports but great for wildlife and getting real close to a distant subject.
 11/05/2004 01:46:33 PM · #4
heres one at the full 500 from about 30ft away



Message edited by author 2004-11-05 13:48:07.
 11/05/2004 01:55:39 PM · #5
Pretty impressive.
 11/05/2004 03:05:02 PM · #6
Wow... I second that "impressive" resonse! Would love to buy some big glass, but I'm still recovering from the initial SLR outlay. Thanks for keeping the dream alive :)
 11/05/2004 03:28:09 PM · #7
Question...

Since Canon cameras will only focus using aperture settings of 5.6 or larger, does this lens lie to the camera to make the camera think that it is really at an aperture of 5.6 at full zoom? If this is the case, will the camera actually take the photo knowing that the lens is a 6.3 and exposure will be correct or does the lens continue to lie to the camera and the photo will be underexposed by a stop and one must use exposure compensation to make up for the extra stop of aperture?

Thanks to anyone who can help clear this up for me.
11/05/2004 03:50:23 PM · #8
Originally posted by wackybill:
Question...

Since Canon cameras will only focus using aperture settings of 5.6 or larger, does this lens lie to the camera to make the camera think that it is really at an aperture of 5.6 at full zoom? If this is the case, will the camera actually take the photo knowing that the lens is a 6.3 and exposure will be correct or does the lens continue to lie to the camera and the photo will be underexposed by a stop and one must use exposure compensation to make up for the extra stop of aperture?

Thanks to anyone who can help clear this up for me.


Canon cameras only focus using aperature settings of 5.6 or larger? News to me..
 11/05/2004 04:27:32 PM · #9
Originally posted by VisiBlanco:
Canon cameras only focus using aperature settings of 5.6 or larger? News to me..

Not quite. The maximum aperture of a lens must be Æ’/5.6 or larger (that is, a smaller Æ’-number) in order for the auto-focus on non-pro Canon DSLR's to function correctly. It doesn't matter what the working aperture is (i.e, you can be stopped down to Æ’/16 when actually taking the shot), but whenever you are composing your shot, the lens is always "wide open" (maximum aperture) in order to give you and the AF as much light as possible. Only when you depress the shutter button does the diaphragm quickly close to the working aperture and then open back up again.

The "DOF Preview" button also stops down the lens to the working aperture. This is a good way to show the brightness difference of an Æ’/6.3 lens, even if you don't have one. Put on your 50mm/1.8, go to Av mode, set your aperture to Æ’/6.3, and while looking through the viewfinder, push the DOF preview button. Notice the difference in brightness. That is the brightest the viewfinder would be when working with a lens that only opens up to Æ’/6.3...

If you have a zoom lens that has a maximum aperture of Æ’/6.3 at the "zoomed end", then one of two things happens:

1) the lens "lies" to the camera and says it is an Æ’/5.6 lens, resulting in flakey auto-focus and under-exposed shots when shooting at the zoomed end (can be verified by looking for bogus EXIF data when shooting at max-zoom)

-or-

2) the lens reports the correct aperture data to the camera, and the AF works sporadically, unreliably, or quits altogether once you reach the point in the zoom range where it shifts from Æ’/5.6 to Æ’/6.3.

Message edited by author 2004-11-05 16:35:00.
Pages:  
Current Server Time: 09/13/2025 07:22:14 PM

Please log in or register to post to the forums.


Home - Challenges - Community - League - Photos - Cameras - Lenses - Learn - Help - Terms of Use - Privacy - Top ^
DPChallenge, and website content and design, Copyright © 2001-2025 Challenging Technologies, LLC.
All digital photo copyrights belong to the photographers and may not be used without permission.
Current Server Time: 09/13/2025 07:22:14 PM EDT.