Sigma 100-300 F4 DG

Hi,
I have this lens too - check out this review for more info :

Sigma 100-300F4 APO Review

And here for some of my Pics with this Lens - many of the Rhodes Holiday ones taken at the Wind Surfing are with this lens as are the ones from Leuchars Air Display.

Check this close-up Pic of my Daughter chillin to some sounds on the beach - handheld

See ya,

Mike

Boswell wrote in post #2088053
At F4 it is very soft and out of focus, at F9 its sharp and at F11 its very sharp, is this how the lens should be? could it be the camera. The JPG are much darker than raw, and there is an improvement if I slide the shadow bar to the right when in raw, but there is a gulf in quality between F4 and F9, F11. If Sigma cant get it right am I within my rights to receive a new lens?

Well that isn't right at all. This lens is pretty good wide open and I never used to worry about using that way at all. I'd be tempted to set all camera settings to default, then use RAW and put it on a tripod. Stick it in AV and shoot at 4.0 and 8.0. The difference should be there not not huge and the 4.0 setting should be perfectly usable. No UV on it either!

I have this lens to. No problem with it. Was getting the hang of hand holding it at 300mm, when I had to send the XT in to Canon. I'm glad you brought up having the warrenty card stamped. I'll have B&h do this on my next lens.

Boswell wrote in post #2088067
these are 2 photos one at F4 and the other at F11 both taken in raw with no adjustments

That doesmt seam to be that bad to me. No lens is as sharp wide open as it is stoped down. The wide open shot looks softer at the top, this may be due to you not having the paper perfectly parallel with the sensor plain. Have you checked to make sure the lense is no longer front focussing by a few mm.

The 100-300EX DG is one of the very best lenses I've used, and now it's in my bag.

Versus some other very good glass http://www.pbase.com/l​ightrules/15lbsd

Versus 70-200IS with 1.4xTC http://www.pbase.com …s/image/6806568​3/original

Versus 100-400IS http://www.pbase.com …s/image/6806568​6/original

Versus (post-recall) 70-300IS http://www.pbase.com …s/image/6806568​8/original

Taken at 300mm (480mm FOV on 20D), Wide open at f4, handheld:

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I used mine today. It's a perfect lens! Try sort it out with Sigma.

Shot my first duck today. AV, f/5.6, 1/640sec, 250mm with a monopod:

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Thanks for the posts guys

I spoke to Sigma today, who tell me the lens has been adjusted as best they can, and if I want I can send the lens and my camera back in again as maybe something happened during transit, but they doubt that very much.

I mean this is really a joke, if they were testing the lens for a fault they must be testinging it first on a camera they know is not faulty, and if its not working on that camera then the lens has an error, if it does work perfectly then its my camera, why do I have to to pay another £25 to send it in again.

They also told me they cannot replace the lens even if it does have a fault as I bought it in HK, I have to go back to onestop digital who must replace it, but they wont as I did not test the lens in their 3 day window.

Does anyone know my rights and who I should talk to, I can't believe the situation I am in.

I don't think there is any point sending it back to Sigmaand I have called canon to see if it could be the camera but that will take another 2 days for them to call back, the camera is still under a year old.

If there is anyone in the bournemouth / lymington area that would be willing to help test the lens on there camera I would really apreciate it.

Please help

Mike

I feel for you Mike.

If I was closer I'd happily meet up and do a compare. Hope you get this resolved. I am surprised at Sigma UK though, they have a good rep for fixing lenses spot on.

it might be the camera and not Sigma, its just the guy at Sigma said hed done the best he could, he didnt say it was perfect. Thats what worries me most.

Boswell wrote in post #2100700
Does anyone know my rights and who I should talk to, I can't believe the situation I am in...Please help

Mike, I'm sorry to hear of your situation. I think the best thing for you to do right now is to contact Sigma's International HQ's in Japan. Email is:

ntl@sigma-photo.co.jp

Sigma Japan is the "big boss", and at least here in the USA, they are the ultimate court of appeal. I (along with others I know) have had Japan rectify issues for me (viz., my Sigma 20 f1.8 ) and they gave me a totally brand new unit after examination. Sigma USA said they had done all they could, and I told them to elevate it to Japan; they did without any problem.

Sigma Japan is usually very helpful, at least with my correspondences with them. A good friend had his 12-24EX fixed there, and another buddy had his 120-300EX taken care of too at Japan. Whatever Japan says, the rest of the Sigma service centers will "obey", so get on Japan and tell them everything they need to know in a cordial yet informative email. They usually respond within 24-48 hours. Let us know how it turns out.

I didn't read all the post, so maybe my post will be irrelevant.

But normally, if you want maximum performance, you need to stop the lens at least
1 stop from wide open. So at 5.6/300mm it should be good. If you use a 1.4x, it's f8.
and with the 2x, it's normally 2 stop from wide open. So f11+ if you want very good
images from a lens.

Sure my 70-200 is very usable at 2.8, but sharpness is better at f4. So when I put my 1,4x on it, I use the lens at atleast f5.6+. I prefer stopping down the lens a little and bumping ISO up to 800. I find the image sharper this way. So in your original picture,
you have a too slow shutter. ( try to keep it around 1/500), you can bump the iso to 400
and stop the lens to f8.

Longtele lens are not used the same way as a normal zoom. Before sending everything
back, use it in real world condition, keep your shutter high, brace yourself... Anyway, you got the idea...

Raphael Emond wrote in post #2102134
I didn't read all the post, so maybe my post will be irrelevant.

Bingo...

This worries me

I also have a copy of this lens, also from Hong Kong, and also too late to get a refund. Mine exhibits strong front focus at 100mm (but I think it's OK at 300mm). I was planning on sending it to Sigma for calibration - I only hope mine turns out OK.

I've not been impressed with Sigma UK lately. I rang them on a couple of occasions about the new Sigma 50-150 f/2.8 that I'd bought. It suffers severe front focus at anything less than 2-3m distance, and particularly in low light. I tested 2 copies of this lens on a total of 4 different cameras and had the same problem in each case. Sigma insist that the cameras must be at fault, even though they all work fine with my other lenses. The first one I returned went back to Sigma and they sent it back to the shop as 'no fault found'. As luck would have it, a guy on the dpreview forum ended up buying that same lens (I noted the serial number!) - he has the same focussing issues with it as I did.

Fingers crossed that my 100-300 works out OK...

Mike - I'm over near Fareham. If you're over this way, I'll gladly try your lens on my cameras (a 350D and a 400D).

Ralph,

Its funny you say that as I got a mail when I got home from Sigma and they asked how far away the sensor was from the target inage and at what focal length, I replied 300mm and about 9 feet with the F11 shot at 1/60 speed and F4 at 1/500.

I'll wait and see what he says, but i will try it tomorrow at 4 meters or so, but in my opinion if it auto focuses then it should be in focus and sharp. I realise I wouldn't normally be using it to shoot so close up, but all my previous shots with this lens have all had the same results.

Thanks GC i'll keep that in mind

Mike