Problem with Sigma 28-300mm f3.5-6.3 and Digital Rebel

[Sector001]

hello all...this is my first time here and my first post so please bear with the newbie question. and i apologize if it has been asked before.

i have purchased a Canon digital rebel along with a Sigma 28-300mm F3.5-6.3 zoom lens. This is a beautiful lens, unfortunately the autofocusing did not work half of the time. it would only work when the scene is really bright or when i extend the zoom to it's 300mm focal length to shoot a faraway subject...

also, when i look through the viewfinder, it's dark, i mean real dark. the sensors won't work. i was wondering if this was a compatibility issue with the digital rebel? coz when i tried the included Canon 18-55mm lens it worked as normal. but unfortunately i did not bring the included lens with me on my trip.

so if i got another zoom lens, from Canon, will it work normally with the digital rebel? i was disappointed that this sigma lens did not work properly with my digital rebel...

does anyone have any experience with this lens and camera? thanks.

[defordphoto]

Welcome to the forum. Several of the Sigma lenses do not play nicely with the new digital EOS cameras. If you contact Sigma they can re-chip it for free, if it's not too old.

[Sector001]

thanks for the quick response and the warm welcome. this sigma lens is brand new, less than 2 months old and the warranty is still active...so if i sent it in, they can fix it?

i sorta figured that was the issue...didn't think to send it for a service. i was gonna try and sell it.

[dn7elson]

i have purchased a Canon digital rebel along with a Sigma 28-300mm F3.5-6.3 zoom lens. This is a beautiful lens, unfortunately the autofocusing did not work half of the time. it would only work when the scene is really bright or when i extend the zoom to it's 300mm focal length to shoot a faraway subject....

Welcome. The problem likely is that the DRebel (as well as 10D) lose their ability to autofocus after f5.6. Since your Sigma lens reduces to f6.3 at full zoom, you will lose AF somewhere after 200mm or so.

[Sector001]

so should i send it in for a repair? will a Canon branded lens be more compatible with the digital rebel?

[Guillermo Freige]

so should i send it in for a repair? will a Canon branded lens be more compatible with the digital rebel?
No, and yes.´
The lens probably just work fine. Sigma has exceeded the minimum aperture for reliable AF with this zoom (the maximum allowed for a non 1-series body is f/5.6) so at f/6.3 AF can fail, and you can´t blame Canon because the lens is out of specs. No Canon lenses has a maximum aperture smaller than f/5.6, so AF will be more reliable. Said that, I must say some Canon f/5.6 teles (as my own 75-300IS) are not so reliable in low light situation either, and it was the case in the film EOS 5 and now in the Digital Rebel, so to push the envelope to even a smaller aperture seems a bad idea to me.

[Sector001]

i'm thinking of getting a Canon branded 35-105mm medium zoom lens (if such a focal length exists), is there a lens compatibility list available somewhere on this forum or another forum?

[Guillermo Freige]

i'm thinking of getting a Canon branded 35-105mm medium zoom lens (if such a focal length exists), is there a lens compatibility list available somewhere on this forum or another forum?
The closest is the 28-105. There is 2 versions, the good one (very similar to the 28-135IS but without IS) with Ring USM, distance scale, and a not so good one (more similar to the kit lens) with Micro USM, no distance scale, and a rotating front. Also the good one is faster (f/3.5-4.5) than the other one (f/4-5.6).
I have the 28-135IS and it works fine with my DRebel. Very fast and reliable AF

[Sector001]

how much is the Canon 28-135IS going to run me? i might get rid of the Sigma lens, even if i can get half the money for it, it be worth it. i paid $229 for the Sigma lens.

[Guillermo Freige]

B&H prices:

28-105 f/4-5.6: $130
28-105 f/4-5.6 USM: $150
28-105 f/3.5-4.5 II USM: $229
28-135 f/3.5-5.6 IS USM: $395 after rebate

The 28-105 II USM is as good, and maybe better, than the 28-135 IS in optical quality and AF speed, so if you don´t need IS or the extra tele, the 28-105 is a fine lens for almost the cost of your sigma lens

[dn7elson]

how much is the Canon 28-135IS going to run me? i might get rid of the Sigma lens, even if i can get half the money for it, it be worth it. i paid $229 for the Sigma lens.

You might want to bookmark this website. Many here have found them to be reliable, having good prices and excellent service.

http://www.bhphotovideo.com

You should be able to have all your, what's available and how much questions answered there. If you have "which is better" questions, you can sure get several opinions here and elsewhere :D .

Also, the Canon EOS lens page with all the information on compatibility,etc. is:

http://www.usa.canon.com/eflenses/

[Sector001]

thanks, i know bandh photo, i'm in the NYC area.

[robertwgross]

I have a different Sigma zoom lens, but when it was less than a year old, the autofocus failed. When I half-pressed the shutter button, it would hunt in and out and never hit focus. Now, if I had been doing that in dim light, then that would have been a user error for me. However, I was trying it in bright sunlight, and it still failed. At the same time, the viewfinder view seemed to dim considerably (as compared to a normally functioning lens).

So, my thinking was that something caused the diaphram to fail in a closed-down position, and that decrease in available light is what caused the autofocus mechanism to appear to fail.

Whatever. I called Sigma and they said to send it in under warranty. It was fixed in a hurry and then worked fine.

---Bob Gross---

[Sector001]

how long did it take for the repair and how good was Sigma's customer service?

[robertwgross]

I believe that I've gone over this history recently.

The lens failed autofocus when it was less than one month old. I called Sigma, and they said it sounds like it needs to be upgraded ( ! ). They said to send it in along with a copy of the receipt that shows the purchase date, so I did. It arrived at Sigma about six days later, and they turned it around and got it out two days later, and I got it back two days after that. It worked fine.

Then, when the lens was less than one year old, autofocus failed again, but in a different way. So, I called Sigma, and they said it sounds like it needs to be upgraded ( ! ). They said to send it in along with a copy of the receipt, and I also sent a copy of the earlier repair paperwork. It arrived at Sigma about six days later, and they turned it around in two or three days, and I got it back two or three days after that. It worked fine.

---Bob Gross---

[Sector001]

interesting, other than the shipping fees, did u have to pay any other fees?

[robertwgross]

There was the cost of telephone calls to Sigma.

---Bob Gross---

[Sector001]

i decided to contact sigma about the problem, i emailed them and got a response quickly. they wanted the serial number of the lens, i have replied. am still waiting a response from them.

it's definitely something wrong with the lens, i just tried the Canon EF-S 18-55mm lens, and it shot beautiful clear sharp pics.

the sigma just won't work anymore. i am in 8 months before the warranty expires. there's also another 3 years extended warranty, but i didn't send in the card... :evil:

i was also thinking of trading in the sigma lens for either another lens or another smaller P&S digicam...but i wonder if the lens will work with other EOS cameras.