At f5.6 the Tamron is sharper, particularly at the edges.

At F11/F16 differences are harder to notice, infact the Sigma is perhaps ever so slightly sharper but it's very slight.

It also looks like my Tamron could have slight de-centering issues - the R/h side doesn't look as good as the left

simon

Still on my quest to decide whether to keep the Tamron or Sigma I've done a series of unscientific test shots.

Lenses are the Sigma APO DG & Tamron DI LD

I've already posted large images on another forum & as I think image sizes are restricted here (please let me know if this isn't the case) the best I can do is link to my original post

http://forums.dpreview.com/forums/read.asp?forum=1036&message=27476732


I'm sure if this isn't acceptable Mr Administrator will let me know asap & I'll remove the post

simon

Excellent card just bought one myself - as mentioned it holds 243 RAW files, although this is on a GX10, should be a few more PEF files

simon

I like the crashing waves and I can see your idea with the blurred foreground, for me though it's too dominant & really pulls my focus to it

just my thoughts

simon

I've had chance to try out the Sigma a little more over the weekend, taking a variety of shots.

I've decided not to post any more images as it's not really my intention to produce a "scientific" comparison - I'll just comment on my own user impressions...

-- Sharpness, inline with reviews my Sigma 70-300 does show quite soft corners at anything wider than F8 - reducing the aperture to F11/F16 does help.
Ultimately I would say that the Tamron produces generally sharper images, not a massive difference at F11 and above but there is a difference

-- colour/contrast, this is where I very much prefer the Sigma. It just seems to produce nicer looking images to me.

-- build quality, I personally prefer the Sigma - feels a nicer lens to use, zoom ring is a little stiff between 200-300mm but I guess this will probably loosen.

-- focus, I can't really see much difference here as both the sigma and tamron can hunt a bit at the long end.

-- Purple, the Tamron shows lots of purple in certain situations although not bad below 200mm, I haven't seen any from the sigma so far.

To be quite honest I'm a little torn now though. The Tamron does seem to produce the sharper images but I'm much more impressed by the colour/contrast and lack of purple with the Sigma - I definitely prefer the "look" of the sigma images, the colours on my Tamron just seem "muddy" in comparison.

Unfortunately I still can't 100% decide, I'll have to try more shots !!

simon

Based on visual impressions the Sigma is smaller - the MF ring is smaller in diameter as is the main barrel when extended.

Just checking them again now, yes the Tamron is probably slightly lighter - although on paper it looks a big difference comparing them "inhand" is difficult to feel much difference. This probably accounts for my thoughts on build quality too.

Received my Sigma 70-300 APO DG Macro today & have tried a few shots to compare it against the Tamron LD DI equivalent I already own. First impressions...

The sigma is slightly lighter/smaller - not a great difference though

Sigma uses 58mm filter, Tamron 62mm

Build quality - the Sigma feels better, less "plasticy" somehow

IQ, early days yet however..

I'm impressed by colour/contrast that the Sigma produces, nicer than my Tamron - the sigma also underexposes less than the Tamron, probably about 1/2 stop.

Sharpness seems quite comparable, taken several shots at 300mm and both are decent. I actually find the Sigma very good at F5.6/300mm.

Here are a few macro shots taken at 300mm (all slightly cropped) - not exactly a scientific test but my initial impressions are very positive on the Sigma, I think I'll be selling the Tamron although I need to do a bit more comparison to be 100% sure.

Simon

Tamron - F5.6 / 300mm Macro




Sigma - F5.6 / 300mm Macro




Tamron - F11 / 300mm Macro




Sigma - F11 / 300mm Macro

Agree with you all, I'll be ordering the Sandisk

thanks

simon

Looking for a fast SDHC card and was intending to buy a Sandisk Extreme III 4GB but just came across the Veho 8GB for less money...

Anyone used these or heard any reports etc ?

http://www.ebuyer.com/product/136210

Thanks

simon

I have the Sigma 17-70 I find it excellent, highly recommend it although it doesn't have F2.8 throughout its range

simon