Just got my Tamron 17-50mm F2.8 XR Di II LD Asp

Neil79 · 15 Sep 2011 at 13:36

Lovely looking lens, heavier than the kit lens too!. However first shots looked abit soft, then more tests they got much sharper and i'm also having difficulty getting the exposure's right. They seem to come out a lot darker than my kit lens, Any tips?

Do i just need to get used to it, my previous lens didn't have a lens hood this one does

matthab · 15 Sep 2011 at 13:59

The stabilized version is not as good as the non stabilized version. At 2.8 it can be abit soft.

My Tamron 2.8f 17-50 non XR is sharp at 2.8 but gets even better if backed off to f4/f5.6.

Have you got any pictures you could show us?

Neil79 · 15 Sep 2011 at 14:19

It is the non VC, non stabilized...

Will do some pics soon

matthab · 15 Sep 2011 at 14:24

sorry thought it was, at work so I could remember if it was or not.

I do find on my 500D it can go soft but not very often.

Neil79 · 15 Sep 2011 at 14:31

No worries, Have only had a quick play of it so need to take it out in the field so to speak

Neil79 · 15 Sep 2011 at 16:43

f2.8

f3.5

f8

Neil79 · 15 Sep 2011 at 17:03

Is it because i'm shooting at 50mm the long end of the zoom at F2.8 is the cause of the softness?

Invertigo · 15 Sep 2011 at 17:18

Wide open, lenses will always be a bit soft. Optimum sharpness tends to be a couple of stops down, hence why the f/3.5 image looks sharper than f/2.8.

Neil79 · 15 Sep 2011 at 17:23

Invertigo said:
Wide open, lenses will always be a bit soft. Optimum sharpness tends to be a couple of stops down, hence why the f/3.5 image looks sharper than f/2.8.

So what's the point of having 2.8?, however I did some shots at 17mm f2.8 and they were pretty damn sharp. I'm still learning as i'm used to shooting at F8-11

An Exception · 15 Sep 2011 at 17:29

This is why I use a focus chart to test for front or back focus as soon as I receive a lens.
If it's accurate on a chart then it will be accurate in the real world (with a few exceptions).

Maybe try to make something similar to below, then you can see if the lens is front or back focusing.

At 50mm DOF get's thinner so if the lens is a little off, that is where you will see it.
ALL lenses are a little softer wide open at their maximum aperture, it's just a fact of life, however all my lenses are still 'sharp enough' to be shot at their maximum aperture, and so should that Tamron if it's a good copy.

Invertigo · 15 Sep 2011 at 17:30

Well, remember, if a f/2.8 lens becomes very sharp at f/5.6+, an f/4 lens will need to be at f/8+, assuming the optics behave identically of course. The Tamron does, as you seem to have noticed, become a bit softer through its range, being cracking at 17mm.

However, at this price there is nothing that can beat it really. The canon 17-55 f/2.8 is sharper at 50mm, but its also triple the cost. There's a reason the Tamron seems to be the 'go to' lens to replace the kit lenses

EDIT: As above, my Tamron is still sharp enough at 50mm f/2.8

D.P. · 15 Sep 2011 at 17:40

I tried 2 Tamron 17-50mm f/2.8 and neither were acceptably sharp, much less sharp than either a Nikon 16=85 wide open or a friends 18-105mm wide open.

Both lenses were returned. I would try a new one. If a 2.8 lens is not appropriately sharp at 2.8 then it is useless.

An Exception · 15 Sep 2011 at 17:44

^^^
Similar experience to me, my first Canon copy was excellent in every way, then wanted to get another Tamron when I switched to Nikon and tried 2 copies, both were crap, so went with an all prime setup instead.

Neil79 · 15 Sep 2011 at 18:03

D.P. said:
I tried 2 Tamron 17-50mm f/2.8 and neither were acceptably sharp, much less sharp than either a Nikon 16=85 wide open or a friends 18-105mm wide open.

Both lenses were returned. I would try a new one. If a 2.8 lens is not appropriately sharp at 2.8 then it is useless.

Now people tell me, Don't have the heart to tell my mum as it was a birthday present for me

An Exception · 15 Sep 2011 at 18:17

First of all you need to work out if it is mis-focusing, it might not actually be the lens at all and instead could equally be an issue with your camera, so it would be a good idea to maybe test another fast lens at a shop or something.

If the lens is at fault, then you need to tell your mum and get a replacement asap, else your left with junk and need to go through Tamron (if it's a UK copy).
Don't see the problem with telling your mum about it tbh, **** happens.

Invertigo · 15 Sep 2011 at 18:26

Samples from mine at 17mm and 50mm, f/2.8. Excuse the crap subject, just got home

17mm

50mm

Neil79 · 15 Sep 2011 at 18:31

^ Exactly the same quality as mine 50mm!, though my 17mm is sharper

Sharpness seems to go down if there is less light... hmm

2Thumbs · 15 Sep 2011 at 18:47

I've owned one (Non-VC) for about 6 months now, and it's very good. It's not great in all situations wide-open, but then very few zooms are. Outdoors for general photography it'll be soft due to all that light bouncing around. But if you can concentrate the light from one direction they're a lot better!

I took this at f/2.8 straight from the camera (RAW to JPEG conversion withstanding)

Excuse the dust.

But maybe that helps?

Neil79 · 15 Sep 2011 at 18:48

Guess I need to test it out on my church photography f8 at 17MM

, F4 does seem to be the sweet spot for close ups.

D.P. · 15 Sep 2011 at 19:33

Make sure you do tests on a tripod (and a decent tripod), mirror locked or delayed exposure, use liveview to focus, remote release or timer. Only then can you tell if the lens is working well.

Liveview is useful for finding focus errors in the lens, as liveview is absed on image contrast and wont have calibration mistakes.

Bewaye of filed curvuate when photographing closer objects like a wall or newpaper for sharpness testing.