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frank
20-01-2008, 17:06
A favour to ask, I have 2 lenses and one is either going to my son for free or going up for sale but I'm not sure which is the better/sharper one. I took 6 photos below on a Canon 40D, each photo is at F9 @ 1/15. the focal length is stamped on each photo, odd numbers belong to one lens even No's to the other lens. All were shot from tripod at the same distance and focused onto the knob on the hosereel. I've deliberately left out the name of the lenses so as not to influence anyone by a makers name. Any chance you can give me a opinion to the better lens from the pics, either the even or odd numbers.
I'll post the lens name after opinions have been cast
http://www.axvk01.dsl.pipex.com/lenscheck1.jpg
http://www.axvk01.dsl.pipex.com/lenscheck-2.1.jpg

Thanks for looking.

foodpoison
20-01-2008, 17:14
hrm. I would be pushed to say the one on the left is sharper. but I'm not sure.
Its really hard to tell.

TomB
20-01-2008, 17:14
Bit hard to tell from that size, and I'm rubbish at pixel-peeing, but the evens look sharper and more contrasty to me.

BRASH
20-01-2008, 17:17
Looks to me the evens are slightly sharper but really hard to say. There just appears to be better (ever so slight) detail on some of the areas of the wall I tried to compare.

Amp34
20-01-2008, 17:36
Yep, my first thought was the ones on the right too.

Take some shots of a piece of newspaper, it's a lot easier to tell sharpness then. :)

dcash29
20-01-2008, 17:52
i'd keep the even number lens

fabs
20-01-2008, 18:19
Even numbers definitely look sharper.

DinoS
20-01-2008, 18:34
after you have decided which lens to keep, what are they?

Canon Bob
20-01-2008, 18:38
I've pixel peeped and would agree with the general opinion that the right hand side (even numbered) shots have a little more fine detail. This may be simply the resolving power of a better lens but could be down to a heavier lens not being influenced by vibration at the low shutter speed these were taken...I assume without using mirror lock-up.

Bob

joxby
20-01-2008, 18:58
There isn't a huge difference between them, all compressed down to fit on the internet, your better off pixel peeping fullsize on screen.
I'd say the evens are slightly more exposed, there may be missing detail in the less exposed odds.
The evens show nicer colour rendition, but the odds might be more accurate.
To be certain one way or the other, you'll have to be more scientific than this.
Crop the hosepipe reel out of fullsize jpgs, and take a closer look

Les McLean
20-01-2008, 19:22
I think you need to take shots at different apertures to really spot any difference, at around f8 most lenses are at their sweet spot, it's only at the extreme ends that generally sort out the 'good' lenses from also rans, so opening wide,or stepping right down and compare may be a better way of helping make decision?

frank
20-01-2008, 19:28
Ok folks firstly thanks for taking the time to look at these for me and I agree that there is very little difference between the two and I have pixel peeped into the original raw files, I thought the even numbers were ever so slighly better..

The lens on the left pics (odd Nos) was a Tamron 28-75mm sp af aspherical xr di ld 28-75 2.8 , lens on the right (even Nos) was Canon 17-85 USM IS lens that Came with the 40D camera. I think I'll be keeping the 17-85 as it is lighter, has IS and well the quality is not much difference to the Tamron but has the wider angle, not the best I know. I daresay I could do more tests but where do you stop. I guess my son has got himself a decent lens for his 300D & kit lens which he also got from me. I think a good malt should be coming my way...would'nt you agree? ;)

inaneredstripe
20-01-2008, 20:58
i couldnt tell the difference myself, but having several IS lenses myself, thats the one to keep.works much better on those shakey days, and when snatching quick photo ops.:)

MGPhoto
21-01-2008, 12:43
Highland, Lowland or Islay?

Enjoy.

Mark

StewartR
21-01-2008, 13:45
There isn't a huge difference between them, all compressed down to fit on the internet, your better off pixel peeping fullsize on screen.
...
To be certain one way or the other, you'll have to be more scientific than this.
Crop the hosepipe reel out of fullsize jpgs, and take a closer lookAgreed 110%. If you're trying to test sharpness, you shouldn't do it with tiny 400-pixel images.