Sharpness problems please help

[abitfishy]

Hi all.

I've done a few shoots and can get some really sharp pic, and then some that look sharp until I view sections of them 100%, then its obvious they are pretty soft.

I decided to do a test with 3 lenses. Tamron 17-50, Tokina 50-135 and a Nikkor 50mm, all at 50mm focal length, at a variety of apertures. I've got 16 crops of the photo I took. All were done on a tripod.

I am not overly happy with any of them, although a couple I would say are acceptable.

Advice as to why these are all so soft would be great. The camera (D90) is near new with 1200 or so actuations on it. Am I expecting too much at full size to expect great sharpness???

Rather than post them all in a thread I've posted the link to the set on Flickr if people would be so kind as to take a look for me.

http://www.flickr.com/photos/4943723...795936/detail/

It would be appreciated as I'm getting a little put off about my photography not even being able to get sharp photos most of the time.

Thanks a lot.

[ricktas]

First off, all digital photos need to be sharpened.

Secondly, to get the very best results you need to have your lenses calibrated to your camera body. When lenses come out of the factory, they are all slightly different, and that can mean micro adjustments are needed to the focusing systems.

I am not sure if the D90 allows AF fine tuning, but check your manual and if it does, you can usually set it up and calibrate up to 5 lenses to your camera body.

You can also use manual focus if your eyes are good. Looking at your photos, focus is WAY off, you did not accidentally have it on manual focus and it just didnt focus in the first place?

[Roof]

I am not sure if the D90 allows AF fine tuning, but check your manual and if it does, you can usually set it up and calibrate up to 5 lenses to your camera body.

Sorry for half taking over this thread but Rick how do i do that ?

Or should i google this ?

[ricktas]

Sorry for half taking over this thread but Rick how do i do that ?

Or should i google this ?

It is NOT a feature of all DSLR out there, the more current models have it. It is called AF micro adjust. It lets you do a series of tests with your camera and lens combo, and adjust the AF system to ensure focus is accurate. The camera body can 'remember' up to 5 lenses and when that lens is attached it takes into account your settings and adjusts focus to ensure that focus accuracy is as accurate as possible.

Here is an instruction page : http://www.focustestchart.com/chart.html

[David]

It is NOT a feature of all DSLR out there, the more current models have it. It is called AF micro adjust. It lets you do a series of tests with your camera and lens combo, and adjust the AF system to ensure focus is accurate. The camera body can 'remember' up to 5 lenses and when that lens is attached it takes into account your settings and adjusts focus to ensure that focus accuracy is as accurate as possible.

Here is an instruction page : http://www.focustestchart.com/chart.html

Thanks to the OP and Rick for this thread: I think I have never read people talking about the need to have lenses calibrated to suit the camera body I have. Might explain some of the softness apparent in my shots more often than I want to remember.. will get them checked out when I take my body to the dust bunny assassin.

[PerfectPicture]

It is NOT a feature of all DSLR out there, the more current models have it. It is called AF micro adjust. It lets you do a series of tests with your camera and lens combo, and adjust the AF system to ensure focus is accurate. The camera body can 'remember' up to 5 lenses and when that lens is attached it takes into account your settings and adjusts focus to ensure that focus accuracy is as accurate as possible.

Here is an instruction page : http://www.focustestchart.com/chart.html

ohh Geez .. THANK YOU soo much for this info, l was feeling sometimes my pictures were not sharp at all, and blaming myself .. never heard of AF Micro Adjusting your Lens to the Camera Body before!

thanks for the original post and everybody who replied, have to re-read it again.
after l googling the heck out of "AF Micro Adjust" .

Now how do you do it on the Canon 50D??

life's a learning experience .. all right

[abitfishy]

Looking at your photos, focus is WAY off

Exactly the point of this thread! All done on AF, with the focus point shown in Viewnx as the leaf you see in them middle of the crops. I couldn't believe it when I zoomed into full size.

And yes, they are crops, not resized images so there shouldn't be loss of quality from resizing.

All exif data as far as I know is intact and shown when I choose 'properties' in the Flickr link.

Single point AF, taken at a variety of apertures from 1.8 (for the 50mm) all the way down to 22 (or maybe 32).

Lack of PP sharpening aside, and just using my Slik tripod, I really think they should still be a lot sharper than they are.

[Adrian Fischer]

might help if there was exif embedded in them. Is the the only test youve done, as in the only subject matter?

[arthurking83]

as someone already said... make sure the exif data is intact!

what software do you use?

if ViewNX( if not, then why not!?) open a file in ViewNX and make sure you click the 'show AF area' button at the top left of the toolbar, so that you can see where the focus point is.

Are you using a single(central) focusing spot?
Is the lens wide open? in very bright, harsh light some images will look a little bit more blurry if care isn't taken to minimise that risk. It's more of a lack of contrast than bluriness.. but it looks the same.
Try underexposing by -2/3Ev top see if that makes any difference.

The images in your link are way too small to form an opinion on whether there is an issue with any or all of your lenses, your camera, your technique or your processing ability.

Resizing an image(and not cropping it) makes it look much less sharp, so the resultant smaller puixels size image will need a teeny amount of 'output sharpneing too' ... but you have to keep that very minimal so you don't get haloing.

At 50mm all your lenses are capable of producing super detailed images.

Tammy17-50 @ f/2.8 and beyond, Tokina(I have no idea, but many folks rave about how good this lens is), Tammy 18-270 is very capable up to about 100mm and at one stop down from max aperture it should produce excellent detail, Nikon 50/1.5 is excellent from f/2.8 and beyond in hard light.
make sure you're using lens hoods if there's any chance of getting light directly onto the front of the lens.

name your tripod!!! weak tripods can be a frustrating source of confusion as to their misunderstood ability(depending on camera setings of course).

D90 doesn't have focus calibration/micro adjust.. but I doubt that'd help anyhow given the described symptom.

IF!!! there's an issue, it could be camera related.. but ATM I'm inclinded to assume it's operator error.. or more accurately operator misunderstanding.

As an example of how to tell what's going on with some of these images:

Image #10 in your series looks to be back focused. Probably shot with the 50mm f/1.8 @ very wide aperture(up to about f/2).
Reason: a lot of lateral CA. Red fringing along the fence palings, and the focus point seems to be on or just behind th every last paling on the RHS, where it seems to get slight sharper.
(lens used could also be the Tammy18-270 wide open as you'd expect to see a bit of fringing with that lens too).
My suspicion is that if you used the 50/1.8 wide open in that shot, there'll be some green fringing starting to show behind the point of best focus.

Are these images all crops of the originals?

etc, etc.... more info will help us to help you.

[ricktas]

How windy was it, how steady is your tripod, etc! This could also be caused by movement of the camera/lens during exposure. Did you do mirror lock-up, prior to taking the photos?

[abitfishy]

Maybe I'm expecting too much at full size. These 2 photos at full size cropped on the face were badly soft too, but resized to these sizes I think are perfectly acceptable (and I quite like the photos too). So is some lack of sharpness at full size really an issue? Should I resize the images down somewhat before I supply them to a model? I'm pretty new to all this....

Edit: After looking at the second one I think thats a bit soft too.

[abitfishy]

After having a think and a look at some of my photos I think I might be having trouble, particularly with my portraits, by using too large an aperture (usually 2.8), not having perfect focus on the eyes and therefore having such a shallow DOF I'm not getting all of the models face in focus.

I've played around with my lenses with a model on Saturday and much prefer my 50-135 as being more practical, so might give it a go next time I head out trying to stick to around F4 and see how I go.

Any suggestions for in camera mode to do with sharpening etc? I've been using Portrait Picture mode (not to be confused with the program exposure mode), and wondering if I should stick to Standard or Neutral? I assume portrait mode probably decreases the sharpness.

In addition, if I did happen to want a better portraiture lens, will a 90mm Tamron Macro be a good choice for something pretty sharp at larger apertures?? Or should I go for the famous Nikkor 85mm? I like this type of photography so definitely think I will stick to trying to get attractive young ladies in focus!

[ricktas]

f2.8 is way to shallow depth of field. Try about f8.

[farmer_rob]

... Am I expecting too much at full size to expect great sharpness???

... It would be appreciated as I'm getting a little put off about my photography not even being able to get sharp photos most of the time.

Thanks a lot.

Firstly, DON'T GIVE UP. It is solveable, and it is likely to be straightforward. You have a good camera, and good lenses.

It seems to me that you are taking on a lot very quickly. It is difficult to track a problem when there are so many variables. I've had a look at your photos on flickr, and there are so many variations, it is hard to get an idea of what is what.

Spend some (more) time on subjects that don't move (e.g. a brick wall) and work it out before trying to take photos you want. I find autofocus a deceptive beast - it promises a lot, but will not actually deliver unless you work at it.

So, some suggestions and comments:

1. At 100%, it is hard to get a really sharp photo - although not impossible - and pointless. You've got heaps of pixels in the D90 - don't waste them on parts of the shot that you will drop later - move closer, zoom in or change lenses. (I try to avoid cropping as much as possible, as the image is invariably degraded.)

2. Sharpening can be issue - if you are using RAW, you must sharpen in PP. If not, you have to be really careful about the picture presets (I do understand the ones you mean.) In the camera menu, you will find some adjustments available for the picture presets. Sharpening is one of these. You may find that portraits have less sharpening. (I don't know - I shoot raw and do sharpening in PP.)

3. Softness can come from
i) wide aperture and hence thin DOF, and then missing focus on the point you want.
ii) Camera shake. VR helps, but you should be at a shutter speed over 1/60 hand held.
iii) Camera shake 2 - mirror slap, light tripod, wind: often apparent at slower shutter speeds (which is why you use the tripod )
iv) small aperture. Above f16 you get diffraction problems on most DSLRs. I noticed some of your flickr samples were f22. There will definitely be diffraction at f22 on a D90, which will appear as softness. Open up (rule of thumb - no smaller than f11.)
v) focus error - the focus points in the camera are not absolutely spot on in the viewfinder on all cameras. This can be a problem at wide apertures (see i).
vi) focus error 2 - back/front alignment. Adjustable on some cameras. Best checked with a focus chart - and I don't think this will be your problem.
vii) bad focus - you just aren't focussing on what you should be.

4. With your test shots, you have a subject (fence?) that will have some parts in focus and others not. Pick a picture with an aperture of f8. Look at the whole picture. Are there sharp spots? If not, then you have a problem with camera shake. If there are sharp spots, are they forward or back from where you want focus? Then you have a focus error problem. (Your lens should have a point in focus - it is just a matter of making sure the focus point is where you want. If there is no point in focus, it is typically because of camera movement.)

5. Work with one lens first. Choose an easy subject that will show something in focus. Work to focus on what you want. Work on a mid-range aperture - f8. Work with a fast shutter speed (1/125 at least.) Get consistent test images, then move on to other apertures and other lenses.

It seems that you manage the light and composition well - getting the sharpness is well worth the effort.

[etherial]

Firstly, DON'T GIVE UP. It is solveable, and it is likely to be straightforward. You have a good camera, and good lenses.

It seems to me that ...

It seems that you manage the light and composition well - getting the sharpness is well worth the effort.

Great post Rob, I appreciate the effort you have put into this thread, your advice seems very logical and well thought out to me.

Good discussion everyone, very helpful!

[kiwi]

AF micro adjusting is a massive furfy

The issue here as Farmer_Rob pointed out could be a range of things, unlikely to be a gear issue at all

Where are you anyhow ? Perhaps you could hook up with a local more experienced photographer who can review your technique

[ricktas]

AF micro adjusting is a massive furfy

I disagree with this comment. In some circumstances AF fine tuning can make a world of difference. Agree that it may not be the case in this instance, but AF fine tuning is not a massive furfy in my opinion.

[kiwi]

I disagree with this comment. In some circumstances AF fine tuning can make a world of difference. Agree that it may not be the case in this instance, but AF fine tuning is not a massive furfy in my opinion.

quote "sometimes its sharp and sometimes its not"

adjust the microfocus ? Hows this help ?

[ricktas]

quote "sometimes its sharp and sometimes its not"

adjust the microfocus ? Hows this help ?

As I said in my post, it might not help in this case, but your comment "AF micro adjusting is a massive furfy" (full stop) is what I replied to. As a statement by itself it is incorrect, and if I took it as a global, overall statement about the benefits of AF fine tuning, others might have as well, and I wanted to correct that.

[ricktas]

Sharpening can help : http://www.ausphotography.net.au/for...ead.php?t=8579