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View Full Version : Sigma 18-50mm f/2.8 EX DC



LR Max
11-30-2006, 06:46 AM
Some of you might know, but I am lacking a good lense in the 70mm and under department (other than the 50mm f/1.8). So I am looking for a very decent piece of glass, would like to stay at or under 500 bucks. This sigma lense looks pretty good.

I photograph in all sorts of conditions, including outdoors and a decent amount in low light. Hence why I chose this lense due to its apeture size. I just wish it had a little bit more zoom on it than 50mm. What is the general consensus on this lense? Pretty good? I couldn't find any reviews on this lense.

The other lense I was looking at was the Nikon 18-70mm lense. I tested one out, good glass there, but like I said before, I will be dealing with low light conditions and the extra apetureness is always welcomed.

Any other thoughts on the subject? Other recommendations? Thank you.

jcon
11-30-2006, 08:54 AM
Its a very good lens and will fill your needs just fine. If that reach is not enough for you, look at the Sigma 24-70mm 2.8. Youll notice though, it starts out a bad length for the wide end.

LR Max
11-30-2006, 10:01 AM
Thanks for the input. I looked into the 28-70mm but I wanted something that had a wider angle to it otherwise I would have seriously considered that lense.

Any input on how this compares to the nikon 18-70mm?

jcon
11-30-2006, 11:38 AM
That Nikon lens(18-50) doesnt compare, its not made for low light photographs, just look at the aperture numbers on it. The Nikon counterpart would be the VERY expensive 17-55 2.8, which is atop my list.

Id go with the Nikon 17-55 2.8 if you can afford $1200, If not, the next in line is the Sigma, then after that in a close third would be the Tamron.

LR Max
11-30-2006, 11:59 AM
Ah. Thanks for the added information. I think I am gonna go for that Sigma 18-50mm here directly.

ryan112ryan
11-30-2006, 12:08 PM
I have that 18-50 sigma EX DC (with the gold ring) and i love it!

the 18-70 woln't cut it for low light and it performs about the same, but that fixed 2.8 on the sigma is golden :D I shoot alot in really low light sitcuations and its worked like a charm

of course that 50 1.8 will out perform them all by a mile, but i never go shooting without both in my bag its deff worth the $400 i spent

eduardofrances
11-30-2006, 02:01 PM
Well since sigma sports a weird quality control system, you should read this review http://www.photozone.de/8Reviews/lenses/sigma_1850_28/index.htm If you are going to buy this lens (as with any sigma lens) go to a store and try it until you find a good copy.

LR Max
12-01-2006, 09:05 AM
Well since sigma sports a weird quality control system, you should read this review http://www.photozone.de/8Reviews/lenses/sigma_1850_28/index.htm If you are going to buy this lens (as with any sigma lens) go to a store and try it until you find a good copy.

Ah, very good advice.

Question: while testing out a lense, what should I be looking for to insure quality? I have only purchased one lense that didn't come with my kit, and it was just the 50mm lense (used Nikkor). Any advice on the subject would be greatly appreciated.

davew
12-01-2006, 10:04 AM
http://www.cambridgeincolour.com/tutorials/camera-lenses.htm

There is a short and sweet read on lenses

eduardofrances
12-02-2006, 09:04 AM
Ah, very good advice.

Question: while testing out a lense, what should I be looking for to insure quality? I have only purchased one lense that didn't come with my kit, and it was just the 50mm lense (used Nikkor). Any advice on the subject would be greatly appreciated.

Go with your camera and try the lenses check for softness in the borders and the center of the image, AF accuracy, if the lens doesn't performs well ask the clerk to hand you another one and test it, do this until you find a good copy :)

If the lens is used check for fungus they look like a spiderweb http://www.chem.helsinki.fi/~toomas/photo/fungus/

:) hope it helps you

tcadwall
12-04-2006, 09:24 AM
eduardo

Go with your camera and try the lenses check for softness in the borders and the center of the image, AF accuracy, if the lens doesn't performs well ask the clerk to hand you another one and test it, do this until you find a good copy

Could you be a bit more specific on how you accurately do this? How would you find softness in a lens in the camera store? Should one set aside hours to devote to this? Really, am I missing something here?

I assume you would have to
1) mount your camera on a tripod,
2) set up a resolution test chart somewhere in the store,
3) ensure your camera mode is set for AF-S so that it has a guaranteed focus lock.
4) Ideally connect your camera to your laptop via usb and use nikon capture to acquire the images so that you can immediately evaluate the images - or have your card reader with you to ensure you can swap it back and forth with the camera and laptop.
5) of course makes sure that your setup is in a place where lighting is not changing - not near a window
6) shoot at an aperature of 11 or so to get the largest depth of field without losing acuteness to diffraction
7) for each lens tested name the images or store them in a directory that reflects their serial number

I am sure that I am still missing something. Maybe I am making this out to be more difficult or more simple than it really would be... but I don't really see how you could easily judge to make sure that you were getting a good specimen - at least not without controlling some environmental variables, having good reference material to shoot, and viewing on a better screen than the camera lcd.

Open for clarification...

tcadwall
12-05-2006, 06:52 AM
bump... Really, I wasn't trying to be a pest. I guess I am just wondering if the softness we are talking about would really be evident through the lcd.

Since I have seen this suggestion quite a few times in previous threads over the last couple of months, I finally had to just ask if this is really a viable option.

I am certain that if I walked into Wolf camera (Ritz, etc) and bought a lens, took it home, was dissatisfied, etc. I might have trouble returning it for another of the exact model. Maybe not so bad the first time, but if I am unhappy the second time, it might not be such an easy swap. So trying them out it the store might be a good idea - I just don't really understand how to make that work without some type of variation on the theme that I sketched out below.

Takers?