Where to post? lens focus prob.

Forbiddenbiker

Forbiddenbiker

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Adam
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Evening peeps.

I've taken a picture today that helps me explain a focus problem I've noticed with my old Tamron AF 80-210 lens, now that I’m using my new DSLR (D70s)

For want of a short description; I find the new camera doesn't appreciate the lens.... it could just be me though.

Shall I post up the picture here or is there a more suitable forum to ask this question?
 
Stick it up here (ooer!) :D

We can always move it.
 
:)
Great thanks, here it is;

Is it me or the lens? 1/320 @ f 5.6 iso200 @ 165mm. Sharpened & detail extraction up to 16, a little contrast and saturation, all in Raw Shooter.
cropped in to about half the original.

Images seem generally ‘flat’ (un-dynamic) with this lens. All the fully zoomed shots where fractionally blurred, the feathers having no clear definition, almost as if my focus point was off, (I’m using auto focus)

I'm hoping the twigs for and aft prove that the focal point is correct, the speeds good…isn’t it? So is the lens just not up to providing a crisp shot? ( it is a cheep lens I know)

Best viewed large to see the lack of crispness. Large Image

heronsmall.jpg


Your thoughts please.
 
Well I don't see much wrong with that at all. I certainly wouldn't go binning your lens on the strength of one shot anyway.

As for whether it's sharp or not is a difficult call - the branches behind the heron may be fractionally sharper, indicating the focus being slightly off, but then again, it's always possible that the bird may have moved fractionally.

I'd do some test shots on a static subject with plenty of detail, but I don't see a lot wrong there to be honest. I'm sure your shot would still benefit from some slight unsharp mask tweaking, but all that apart, it's a good shot and one you can be well pleased with. :)
 
Yes sorry CT, thanks for the nice comment, its not a very scientific test is it, Its just that I notice the difference broadly across all images from this lens, and I tend to use it when taking pictures of wildlife, where as the 18-70 Nikon lens used in tandem shows nothing like the softness at the same speed.

I'll do some static tests, and use the Nikon lens as a comparison in some way..Don’t know how I'd do that yet...focal length?
Can the auto focus be slightly out, if the lens is worn or whatever?

Mr Heron here, is one of the main residence of the Victoria Park lake and today decided to sit very close to shore, giving me some lovely full frame shots of him, I guess that’s why I'm disappointed because I expected then to be 'right in my face' kind of photos, where as I have to satisfy myself with this cropped 165mm. :confused- :D
 
A brick wall is a good subject to test lenses - plenty of fine detail in the bricks and mortar. Mount the camera on a tripod to eliminate any chance of camera movement and make sure the camera is square to the wall. :)

Generally speaking, when photographing wildlife always try to focus on the eye, or at the least - the head. I use servo focus for wildlife shots.
 
If you are using Rawshooter make sure that you have noise suppression, colour noise suppression and hot pixel/pattern noise suppression at set to zero, and for testing at least, sharpness and detail extraction at zero or even minus numbers when converting the files. All these setting effect the detail outputted to the converted file and could add another variable into the equation to make potential problem solving less accurate.

Looking at the larger picture I would tend to agree with you though and say that it is not capturing the levels of detail that I would hope for but as CT has pointed out, until you have performed a more realistic and controlled test it is hard to point the blame 100% at the lens.

HTH
 
Excuse me for not answering sooner.

Thanks for your thoughts Steve.

I haven't been using Raw Shooter (free) for long, as I’m just trying to convert my photo workflow to Raw from jpeg, I didn't get on with the Nikon software (PP) at all, waaay to sluggish and slow for my machine.

I'm quite impressed with Raw Shooter though, and I seem to have more control over more (unknown at this point :D ) aspects of photo editing. Needles to say I haven't even touched the suppression controls. :confused:

I've just had a cancellation on a job this afternoon and I’ve got a few hours before visiting my son...so watch this space.

Some semi sharp pictures of a wall coming up....although it’s raining now....so it'll be a wet wall.
I won't do any editing, just size.
 
I took 3 photos, all at ten feet from a grey block wall at full zoom. It was raining on my camera, so these are shot out of my window onto a dry workshop wall :p ;) . All three photos where identical. (To the extent needed for this test anyway) No one photo could be chosen that showed any more or less sharpness than any other.

Straight out of the camera. Converted RAW in Adobe to jpeg, resized for web in fireworks.
210mm, 1/13 sec, f6, iso200.
Edit; On a tripod using the timer to fire the shutter and out of the wind
I've just realised some of you may consider the speed a bit low to do this test justice....

This photo is full frame.

wallenstest.jpg


And this is a cropped section of the above. (A crop of the full sized original)
zoomwallenstest.jpg


Seems really obvious now, what do you peeps think?
Should I be able to get more from this lens?

I've also noticed the dirty part of the block on the left seems to be affected more...other shots of cleaner blocks show the same level of detail across the whole image. :confused-
 
I have to admit that pictures are not great but neither is your technique. A grey wall with very little contrast to give good focus lock, 210mm, 1/13 sec, f6 with anything other than mirror lockup and taken of a sturdy tripod (not resting on a wall) could also easily introduce camera shake.

Is it not possible for you to pick a "normal wall" use a tripod, mirror lockup, F8 and preferably a faster shutter speed as well? You will probably need to wait until better lighting conditions and no rain to do the test but there really is no rush.
 
Incidentially both shots are well underexpossed too, which will also not help much :(
 
wallenstest.jpg


Your first picture with exposure corrected and some sharpening applied in Photoshop. Although it doesn't answer the question you have directly, it does show what can be done and the level of detail that can be extracted.

HTH
 
I don't think the 1/13 sec exposure matters as long as the camera was on a tripod and the shutter released with either a remote release or the delayed timer.

The fact that the pic is sharper on the right than the left seems to indicate that the camera wasn't square to the wall, which is vital for this sort of test to mean anything at all. Certainly looking at the line of mortar it seems you weren't parallel to the wall - you need to set up for this very carefully. A brick wall would be better and contain more detail.

It's not unusual for digital photos to need sharpening from the original, in fact it's fairly normal, so I wouldn't pass judgement on your lens until you've taken a better set up shot. :)

Tamron lenses have a pretty good reputation. It's possible to get a bad lens of any make, but you really need to take a better control pic. ;)
 
Yep - looking at Steve's edit, the detail is there, and I'd put the poor detail on the left down to the camera not being parallel with the wall.
 
OK Ok, I’ll do them all again. :( I’ll get me motorcycle frame laser alignment tool out next time. ;)

Although I’m not totally sure the infill dirt hasn't affected the amount of detail extractable myself, but I did rush the job, and I agree it doesn't look straight, so you’re all probably right….strange though, as all the other test shots before the 3 are ok. I'll add mirror lock up to the list too.

I can understand the auto focus being aided by higher contras, but didn't think that would be a problem with the reasonable light, although I’m sure your right to suggest I get it right. I just thought the finer surface would be more suitable.

Steve said:
Incidentially both shots are well underexpossed too, which will also not help much :(
Click to expand...
I was using Auto and that always seems to underexpose occasionally...or have a biased toward underexposing occasionally. And I had my ‘don’t fiddle with the image’ head on.
Well that’s my excuse and I’m sticking to it. :smilenod:

CT
You’re absolutely right, I have no intention of wasting a good lens, and the thought of forking out for a new lens only to find is was my technique makes me shudder. :doh: That’s what I’m sacred off! It could all be me after all.

I’ll do some googling and Then I’ll do it again on a normal wall, I'll pay close attention etc.
I'm kinda hoping it is my poor technique as that would be more rewarding photographically...IYKWIM. Although that kinda suggest that I’m unable to take an in-focus picture of a flat wall ten feet away...which I’m sure is not true. :D
Thanks for your thoughts everyone. I'm really looking forward to finally understanding this problem.
 
Steve said:
Your first picture with exposure corrected and some sharpening applied in Photoshop. Although it doesn't answer the question you have directly, it does show what can be done and the level of detail that can be extracted.

HTH
Click to expand...
yeah, I've just had a look zoomed in 200% (which is about the same as the original zoom) You've done a great job there Steve details way up, although I think I still see the slight fuzz....and I realise its not the original or anything.

Just shows what can be done with a bit of knowledge I guess..
I've got a few more shots if you want to have a go. ;) :D
 
Just a thought FB and nothing to do with your lens test, which you should still do, but a common cause of unsharp photos with autofocus cameras is using Single Shot focus. There's nothing wrong with Single Shot, but when you press the shutter halfway and get the green focus confirmation light, the focus is locked at that point. The longer you hang onto that half pressed position the more scope there is for you and your subject moving sufficiently to throw your shot out of focus. For this reason I always take my finger off the button completely having attained focus and when the decisive moment arrives, press the shutter smoothly all the way, which allows for any slight re-focus needed for your own or the subject's movement.

It's not the best way to work anyway with wildlife shots, which is why I prefer servo focus, where focus is continuous all the time you have the shutter button half pressed. :)
 
Thinking about it now I tend to constantly re-focus by reapplying in single shot mode. I've tried servo focus a few times as well, very impressive and fast I find, but with this longer lens it tends to shoot off whilst tracking into blur land and I lose touch with my subject too often. (I realise that’s all my poor technique.)

I have thought about using the 'dynamic focus area' on servo focus, the five segment thing, which might help keep me in touch. Haven’t tried that yet though.

Thanks for the tips CT, much appreciated.
 
My old man has been doing photography for donkey's (30 years i guess) he has used digital for many years and currently runs d2x's as his main cameras and he has always said to me that all digital pictures need to be sharpened it is just the nature of the beast.
 
Hope you like it. :fingerscrossed:
This is what kitchen walls look like round here by the way. ;)

210mm, f6, 1/100sec iso200. About twenty feet.

Some contrast/colour and 'sharpen edges' applied.
What do you think?
lenstesttwo-01.jpg


Large Image:
I think with a little effort way more detail could be pulled, but even at this ^^ stage I can still see the fuzz when zoomed in, but perhaps I have to agree with the majority of you, the lens does seem to focus, although its just not high in detail.

Am I expecting two much from this lens do you think? I know little to nothing about lenses. :)
 
Seems to be sharper on the right than on the left again. Weird.
 
Yeah it does doesn’t it. It’s not the set up. All the images are like this. 30 adjusted shots in all, all because I kept going back and trying again because of this exact problem.

I double checked and triple checked my angles, 90degrees everywhere.
I do motorcycle frame alignment as one of my main specialities...so I do know what’s straight or not, or how to measure straight...please believe me. :( ;)

It’s not the setup, so it must be the lens. ???

Anybody else?
 
If the setup is correct as you say then it could well be one or more of the glass elements in the lens could be out of alignment, that would cause the results we are seeing. The big question is, if thats the case is it worth getting fixed or for the cost would it make more sense and be better to spend that money on a new lens?

Its a tough call...
 
Try doing a portrait photo as well next time, if the blur moves with the camera then its the lens.

:)
 
It doesn't look good does it? :(
 
I just gave everything left of the red line a one shot sharpen - the detail is there to be extracted and it would still stand a little USM.

walltest.jpg


You shouldn't have to go to these lengths though, and the lens does seem to be out of whack.

Great wall though! :D
 
I've just been through every photo again, And it seems obvious now, doesn't matter what the focal length is it always appears slightly out of focus on the left.

It’s not worth getting it fixed eh, but it’s also not a bin job either...although I’ll probably steer away from using it... or just place subjects on the right of frame.

Kind of wish I hadn't asked now. :( :D

Many thanks for your efforts and thoughts chaps; it’s good to finally know.

... It wasn't me. :D

:)
 
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