Tamron 18-50 f2.8

[schdaefan]

Hey guys,

bought the Tamron 18-50 f2.8 for my K10D some weeks ago. Now I got my second lens, a Pentax 18-250 f 3.5 - 6.5. After some first shots it seems that the pictures with the Pentax are a lot sharper than with the Tamron, which I didn't expect.

I am wondering if my Tamron has some quality issues and if it is worth sending it to Tamron, because it will take some weeks to get them back.

Does one of you have any experiences with that?

Can it be a settings problem from the camera, which I haven't found yet?

thx for your help
Stefan

[spiraleyes]

Post some pictures that you think have problems. If you are setting the camera at a very low fstop (2.8), you'll get a lot of softness.

[jgredline]

I am with Jim. Post some pics.

[schdaefan]

Here are some pics. I hope this helps. I just resized them

[schdaefan]

Here are some more....

due to a lack of computing power on my current laptop, I didn't start to work on the pictures

I have the impression that details are often not sharp, e.g. trees, leaves, faces, letters....

btw: look at the clowed at the fourth picture

[spiraleyes]

I agree, those pictures aren't very sharp. Some of the pictures where you're in the forest could be having issues with sharpness due to some camera shake.

I notice that all of these are taken in multi-segment metering mode. I wonder if that has something to do with it?

Have you taken any shots on a tripod? I'm interested to see if they are still soft when set to a proper Fstop.

Javier, what are your thoughts on this one?

[PeteE]

What camera are you using? Shooting in Jpg or Raw? The reason I am asking sometimes the same picture shot in raw and jpg The raw will be fine without processing but the jpg will be soft. It may the way the camera is set up, more than the lens. Reading a post, the author was talking about a lack of sharpness in jpg's vs raw and suggested setting the sharpness in camera up two and contrast up one. I tried it and it seemed to help.

[jgredline]

Well, in looking at those images they are really not acceptable. Even the ones at F/5.6 are soft. I would be curious to see some images from another lens to eliminate the lens as the problem. Now from what I have read, heard and seen, the Tamron 17-50 F/2.8 , has had some quality control issues. When they are good they are very good, but when they are bad, they are very bad...Jim also brings up a ''very good point' Get out of the habit of using multi segment metering and consider using spot focus as well.

[schdaefan]

Hi
thanks for your replies so far. I am using a k10d, which I just bought some weeks ago. So I am still figuring out how everything works. It is my first SLR. I didn't use a tripod so far.

I received my Pentax 18-250 lens last week and it seems that these pictures look a lot sharper with the same camera settings. I made all pictures as jpg so far in the highest quality.
Having read that it might be a camera problem, I changed the sharpness setting in the k10d to +2. I had the impression it improved a bit, but still they are not sharp.

I will post my first test shots with the pentax lens here. It seems that it is a quality issue from Tamron.
So I guess I should send it back to Tamron. What do you recommend?

[jgredline]

Those images are much nicer.
A tad, I would guess a 1/3 to 1/2 stop underexposed but much better.

[spiraleyes]

Agreed, those pictures are much better, but a tad underexposed. You can correct that if you shoot in RAW.

As far as bumping the sharpness up, I haven't had to do that in my K10d. Then again, I haven't played around with those settings at all.

The lens is going to be the determining factor on sharpness.

I think this picture is a good example of a sharp subject and a good bokeh. Taken with my Pentax 40mm at 2.8. Shot in jpeg:

[jgredline]

Jim,
That's a nice image. Is that the pancake lens?

[spiraleyes]

Yessir, taken with the pancake.