steve_t wrote:
That's camera shake, not lens sharpness (higher ISO = faster shutter). Lay off the coffee for a bit.
I don't drink more than 2-3 cups of coffee a week or so.
As for the shake, I was shooting on a tripod, with remote release and mirror lockup, indoors, taking pictures of a static, inanimate subject, at both low and high ISOs. What more could I do to reduce shake?
saaketham wrote:
They all look horribly soft. Just like the Tamron 28-75 and Sigma 24-70 I recently bought on Buy & Sell. By f/4, images are much sharper and f/5.6, it's great. f/8 seems to be the sweet spot. Did you try shooting with higher ISO. I got sharper images at f/2.8 when shooting at ISO-400.
On those particular test images I shot ISO 100, it was too bright outside to use 400. Anyways, the shutter speeds were well over 1/150th so I imagine it wouldn't make a technical difference. The lens does sharpen up quite a bit at F4 and it's very good by F5.6. I guess it's just not a wonder lens @ F2.8.
I can't decide if my case is normal or to send it back and demand it be calibrated till it's sharp @ F2.8
I've read of many owners claiming "mine's incredibly sharp at f/2.8". But, when asked for 100% crop, sharp samples at f/2.8, nobody posts anything. Instead, some post sharp images at f/4 or narrower. These are 100% crops, no sharpening, only contrast adjusted. The links show actual image sizes.
- At f/4
- At f/4
- At f/11
- At f/2.8
saaketham wrote:
I've read of many owners claiming "mine's incredibly sharp at f/2.8". But, when asked for 100% crop, sharp samples at f/2.8, nobody posts anything. Instead, some post sharp images at f/4 or narrower. These are 100% crops, no sharpening, only contrast adjusted. The links show actual image sizes.
- At f/4
- At f/4
- At f/11
- At f/2.8
It looks like you got a really sharp copy, it looks decent even at F2.8. I should definetely do some F4+ shots to compare. What ISO/shutter speed were these taken at?
Also for a 100% crop did you just randomly crop what you thought was the middle and save the file or is there a better way to post a 100% crop?
saaketham wrote:
I've read of many owners claiming "mine's incredibly sharp at f/2.8". But, when asked for 100% crop, sharp samples at f/2.8, nobody posts anything. Instead, some post sharp images at f/4 or narrower. These are 100% crops, no sharpening, only contrast adjusted.
Them's fightin words. Here's a quick test of the Tamron @28mm and F2.8 through F5.6
Tripod mounted, ISO 100 & MLU enabled, best of three each on a 350D. http://www.pbase.com/sp_todd/image/43874337/original
Usable at F2.8 I think you'll agree.
steve_t wrote:
Them's fightin words. Here's a quick test of the Tamron @28mm and F2.8 through F5.6
Tripod mounted, ISO 100 & MLU enabled, best of three each on a 350D. http://www.pbase.com/sp_todd/image/43874337/original
Usable at F2.8 I think you'll agree.
Judging from your pics I think i've come to notice that almost all the lenses are pretty sharp @ F2.8-F4 when it's an up close shot within 5 feet or so. When I shoot the box the lens came in i'm not too dissapointed @ F2.8 and i'm actually happy with F4, however when I go outside and shoot something 100 feet away F2.8 it's another story.
[Judging from your pics I think i've come to notice that almost all the lenses are pretty sharp @ F2.8-F4 when it's an up close shot within 5 feet or so. When I shoot the box the lens came in i'm not too dissapointed @ F2.8 and i'm actually happy with F4, however when I go outside and shoot something 100 feet away F2.8 it's another story.
Is that an autofocus issue or an optical issue? What are the results when you focus manually?
