Zoom too soft?

garry71

garry71

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Name
Garry
Edit My Images
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I've got a Nikon D3100, and a Tamron SP 70-300 VC lens.
I realise zoom lenses aren't the sharpest around, but I thought this was looking a bit too soft at 300mm, especially as distance grows from the subject.

A couple of examples:
This one of the deer was at F11, about 50 feet away.


DSC_1608 by gvp1, on Flickr

This one at 30 feet away, wide open:


DSC_2050 by gvp1, on Flickr

This one at 6 feet away wide open.


DSC_2243 by gvp1, on Flickr

In camera sharpening is set at the factory default of 3/10, noise reduction is turned off, and vibration control is on, and seems good down to about 1/30th sec.

I know zooms aren't brilliant wide open, so are these what I should be expecting?

And does this one at 155mm look ok for sharpness?


DSC_2257 by gvp1, on Flickr

Thanks a lot
Garry
 
It would be wise to leave your exif intact when asking questions like this Gary. However #1 looks like you have missed focus altogether on the eye`s of the Deer, #2 only guessing but I would say shutter speed slower than the focal length used and handheld technique not perfected enough :shrug: #3 not even a clue as to what aperture or shutter so cannot really comment #4 looks good (y)
 
The last shot is pin-sharp, really good.

Looking at the EXIF for the last two shots because they're the same subject) there are many differences; the ISO changes from 400 to 800, the aperture on the top eagle shot is f/5.6 but f/4.8 on the bottom one. The shutter speeds are the same but the focal lengths have changed, which will have an effect.

I'd expect the last shot to be sharper, if only because you're shooting mid-way through the focal length of the lens where you'd expect lenses to be a bit sweeter. At the long end these cheaper lenses do have to compromise in order to fit their RRP, and usually that manifests itself as a slight softness at maximum focal length and often, at their widest aperture.

Hey, don't think it's only limited to cheaper lenses though; my 70-200mm is sharper at f/4 than f/2.8, but it's a minute differences that wouldn't really show on anything big bit reproductions.

The grey hawk has been shot at 300mm and at f/5.6 so you're pushing it for performance. plus you have ISO 2000 set on the camera, which won't help the perception of sharpness.

The deer shot looks mis-focussed and it's a busy scene anyway so had to clearly see the area of focus. And it's shot at 1/40th, which is a no-no, even with image stabilisation or VR. Plus, it's at f/11, which is where diffraction sets in on many lenses.
 
Thanks for the replies.
I'll go back out again and keep the shutter speed up this time, and rely less on the gismos. Have to admit I've been relying on the vibration control too much. I had it on auto iso as I'd have been going through menus every other shot otherwise, that's why it changed between the 2 pictures.

I thought getting a dslr and anti vibration lens would make more shots possible, but it's starting to look like you have to be just as careful as with a film slr. Probably just pushing my luck a bit.

Cheers
Garry
 
Garry - IS/VR/whatever will make more shots possible, but they'll be dictated by good technique and setting your gear up right. I see it as a safety net that may help me, not a crutch that I rely on all the time.

To avoid going into too much noise, can you set an upper limit on the Auto ISO, say ISO 800 or 1600, so you know you are controllable noise levels?

Also, combining this with Tv mode will help in many cases because you'll have a predetermined shutter speed inputted at all times (say 1/500th) and the aperture and ISO will be altered by the camera automatically to adjust exposure. Might help.
 
I'll do that on my next try then; leave it set to 1/500th and limit the upper iso.
The noise is fairly good on my D3100, even at 3200 I haven't had anything looking horrible, (apart from my input :shake:)

It's a shame you can't set cameras up to automatically adjust the minimum shutter speed to be suitable for the zoom focal length at the time. That'd give a bit more scope with aperture and iso (I think!)

Thanks for your help :)
 
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Sorry to but in Garry, Pat,you say diffraction sets in at F/11,.
I usually on bright days have mine set to that.
Would I be better at F/9 or 10.......I know it depends on't lens,but in the old days F/11 was the sweet spot on most lenses.:cautious:

PS
Garry,the last 2 photos are crackers..
 
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Gary,
By sheer coincidence I have posted a similar thread regarding the focus sharpness of my Nikon 55 - 300 lens on my D5100 only this evening.

I seem to have fallen foul of trusting the VR system to take care of shots which I should not have attempted.

Think I will up my shutter speed or use a tripod where I can.

V
 
I saw your thread, I was sorting mine out when you posted it! I would have gone for your lens, but I liked the manual override on the Tamron.
 
Can I suggest you take some test shots wide open on a tripod to eliminate camera shake? Shoot something static in the garden or similar.
 
Towershot - f/11 is a generalisation. Some lenses it may be a sweet spot (probably those designed for 35mm) but I know it's edging it on some of my lenses, namely my Sigma 14mm. I suppose it's all down getting used to the peculiarities of a lens and if that means doing test shots to show where it's good (and not so good), then that may be the way.

If you're getting good results at that f-stop then cool. :)
 
I've got some 100% crops from test shots today.
The camera was on a heavy steel tripod, and the self timer was used to avoid vibrations.

I showed these and some others to Jessops today, and they're getting another lens in for me, so hopefully that one will be ok!

Thanks
Garry



DSC_2514 by gvp1, on Flickr


DSC_2516 by gvp1, on Flickr


DSC_2519 by gvp1, on Flickr


DSC_2509 by gvp1, on Flickr
 
Garry - a change of lens will hopefully sort things. Those test shots are decidedly ropey, even the first shot at 1/400thsec.
 
I'll keep my fingers crossed!
Thanks for the advice as well Pat :)
 
Hope the new lens is much better Garry, as they certainly don't look good...

Unfortunately, no EXIF data on the photos, so just to check on the last set that you were on the tripod, you did switch OFF the VC on the lens ?

I'm not sure how the Tamron VC works - some have an automatic tripod sensor, some you manually switch the VC off - I always make sure I switch the IS off, if using a tripod / monopod, whichever type it is (hope this makes sense)...
 
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I picked up the replacement lens, and it's much better sharpness at 300mm than the first one. I duplicated the above test shots handheld this time, and they're loads better, even without the tripod.
Since I got the new lens, it's been grey and dull each day, so not worth going anywhere with it yet :bang:

Thanks for all the replies.
 
Glad yo got sorted, its horrible when you get something faulty
 
Yep good to hear and would be really good to see some shots with the new one(y)
 
Here's a couple with the new lens wide open at 300mm. Not mega sharp, but still much better than the old one stopped down.

Just need to work on my composition now!




DSC_3004 by gvp1, on Flickr


DSC_3091 by gvp1, on Flickr
 
Chr1stof said:
Glad yo got sorted, its horrible when you get something faulty
Click to expand...

Cheers. I find it's the aggro of taking it back that's worst. Having to show how it's faulty to someone who isn't listening properly, then having to tell them that their return policy isn't actually the law, etc, etc.

The girl in the shop basically admitted it'll be put back on sale again, so I told her it'll just be returned as faulty again.
 
garry71 said:
I find it's the aggro of taking it back that's worst. Having to show how it's faulty to someone who isn't listening properly..
Click to expand...

I hate taking things back to shops :( I just hope when I purchase my camera and lens there are no problems because not knowing anything about cameras, I'm sure I'd be at the mercy of those sales twerps.

Glad you've got your problem sorted though Garry & I love that shot of the deer . :)
 
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