some photos not sharp, others are, why? [larger img]

[OreoCookie]

I was the semi-official (read: unpaid) wedding photographer at a friend's wedding and for the most part, I'm very satisfied with what I've produced. However, I've noticed that some pictures are not sharp, although they should have been. I want to exclude errors on my part before I consider giving the camera into service.

Here are a few examples, all of them are shot at 1/60 s, the usual maximal flash sync time in A. The aperture is always around 4, I chose ISO 400 and my Nikon D80 produced jpgs (I had to). In the following four pictures, the first three are not as sharp as I'd have liked them to be, the last one is what I expected. I've linked to the original.

This is the `good one'.

All shot with a Nikon D80, 18-70 kit lens; shots with my 80-200 zoom are sharper if you compensate for the dof and the longer focal length. Is something wrong with the lens? Or is it me, the photographer?

 

[baby duck monge]

1) please! (Just kidding, but even with your warning expect someone to say it.)

2) ISO 400 will make things a bit less sharp just due to noise.

3) The kit lens is not the sharpest tack in the bunch. It's no wonder you see improvement with the 80-200 (as long as you're shooting nearer to 80).

4) f/4 is going to provide a fairly narrow depth of field. If you miss your focus at all, you're not going to have satisfactory results. Light permitting, you should really close it down at least one, if not two or three, stops if you're having trouble hitting your focus.

5) You may have just missed your focus slightly on the first three shots. Auto-focus may be quicker, but it's not always as accurate as manual focus.

 

[OreoCookie]

Yeah, one of the things I found out is that I should not use the 80-200 zoom with AF-S, but always with AF-C. At first, I thought my camera had focussing issues with that lens, but then I found out that the dof is so small (literally a few centimeters!), that the subject has either moved out of the plane of focus or that the AF was accurate and focussed on the nose, for instance, but the eyebrows were already too far away from the focal plane

I should mention that I'm an experienced amateur (taking pictures for over 20 years now, 10 years with slrs) and that I haven't noticed such problems before. Perhaps because you can't with run-of-the-mill digi prints that use only 3 MP.

 

[teleromeo]

the good one looks wide angle, the others are zoomed.

If you have photoshop you could apply some smart sharpen before printing.I have goods results at 300 dpi with these settings :

smart sharpen
lens blur
amount : 100 %
radius 1 pixel

I always print on a professional photo lab (fuji frontier)

 

[ChrisA]

You can determine if it is a focus error, if so then some other part of the image will be in focus. For example in a group shot everyone was to be a slightly different distance. If no one is sharp then it is not a focus error, it's just a not-sharp image. So you look at subject motion or camera shake as the source. The kit lens is prety good for the money but does not compare to Nikon's f/2.8 zooms or a prime.

Try a simple test at home. To see if you should blame the equipment. Tape a newspaper to the wall and shoot a few frames of the paper at your normal distance using different f-stops and focal lengths. Newspaper makes good test subject. A decent lens will let you read even the small print an better lens will let you see the imperfections of each letter were the ink interacts with the grain in the paper or the shape of each dot in a halftone image. Next get a tripod and repeat the newspaper tests.

Don't expect sharp images from the kit lens zoomed all the way out and running at f/5.6 hand held with normal indoor ilumination bcause you will be using high ISO and slow shutter.

You can check for a focus error. I actually had this problem on one of my cameras. There is an adjustment, done with shims so that the optical path length to the focus screen and the film plane are equal. If they are not equal then a best focus in the viewfinder means a poor focus on the film. Easy test is to shoot a bunch of books stood up at different distances. get a tripod. Focus on one book and see if another is sharp in the recorded image. But this should effect all lenses. This error happened after I sent a camera in to have the shutter replaced. The technition said "sorry, my fault" and fixed it.

 

[GyroFX]

wow, i give you credit for your bravery, not only using a kit lens, but using a lens with more than F2.8 indoors at a wedding.

the 18-70 is a relatively good lens for normal usage, with adequate lighting. But under your circumstances, the results will vary. A faster lens with a constant 2.8 or less should produce better results, with easier focus as well.

What type of flash did you use? I'm thinking you need a diffuser on that thing so the light can be evenly spread out. i.e. having the light bounce off the ceiling, and soft lighting in front of the subject as well. Sort of like using umbrellas...except not.

 

[OreoCookie]

@ChrisA
I'll definitely give it a try tomorrow.

@teleromeo
I'll sharpen the pictures at the end

wow, i give you credit for your bravery, not only using a kit lens, but using a lens with more than F2.8 indoors at a wedding.

Thanks
I told them that I'd be happy to be their wedding photographer and they'd have to cover my expenses only ... needless to say, even though I've offered to rent equipment, they denied.

In the church, my bazooka (2.8/80-200 zoom) was my main gun. I didn't know how to pull it off, but I think the results are quite nice for handheld shots with a 1.5 kg lens. (I leaned against pillars to stabilize it.) For group shots it certainly isn't the right tool.

the 18-70 is a relatively good lens for normal usage, with adequate lighting. But under your circumstances, the results will vary. A faster lens with a constant 2.8 or less should produce better results, with easier focus as well.

So basically, you're saying I don't need to have my camera serviced, it's what's to be expected from the equipment?

What type of flash did you use? I'm thinking you need a diffuser on that thing so the light can be evenly spread out. i.e. having the light bounce off the ceiling, and soft lighting in front of the subject as well. Sort of like using umbrellas...except not.

I used an SB-400 -- sufficient for parties and all, but a tad small for a wedding. I bounced a few times, as a matter of fact, the group pictures were taken with a bounced flash. In the church with a 10 m ceiling, this was a pointless endeavor, though Ditto for the dinner (5-6 m ceiling).

 

[saltyzoo]

One word of advice. Pun intended.

Monopod

 

[Doylem]

Wow... you've reminded me why I hate weddings so much...

 

[Westside guy]

So basically, you're saying I don't need to have my camera serviced, it's what's to be expected from the equipment?

I don't think this is correct - certainly not when combined with a flash. I had the 18-70 and it is quite sharp. 1/60 shutter speed with the flash should have given you sharp pictures.

My first thought was focussing errors, but a cursory glance at the pictures didn't bring any obvious "wrong point of focus" to mind. Were you being careful with your technique? Could the answer be as simple as blaming small camera movements while depressing the shutter?

 

[GyroFX]

Thanks
I told them that I'd be happy to be their wedding photographer and they'd have to cover my expenses only ... needless to say, even though I've offered to rent equipment, they denied.

I guess if you're using flash indoors, it's a different matter. I've only helped film weddings before, never photos

So basically, you're saying I don't need to have my camera serviced, it's what's to be expected from the equipment?

for me, i'd have to take pictures under normal light to see the difference. Do some focus test as well. Maybe there is a problem?

I used an SB-400 -- sufficient for parties and all, but a tad small for a wedding. I bounced a few times, as a matter of fact, the group pictures were taken with a bounced flash. In the church with a 10 m ceiling, this was a pointless endeavor, though Ditto for the dinner (5-6 m ceiling).

Maybe you need a more powerful flash like an SB800 or so for the higher ceilings, etc.

I like naturally lit pictures myself, without the aid of flash, so I'd lean towards a 35mm or 50 mm 1.8/1.4/1.2 prime. I'd only do flash if I knew I can get away with a more natural looking photo. But that's just me.

 

[teleromeo]

I'll sharpen the pictures in a last step

I believe that is the way you should do it.
Just play a bit with the settings so you have the best result when they are printed.

Wow... you've reminded me why I hate weddings so much...

you're not the only one ...
IMO, the only good thing about weddings is the champagne

 

[OreoCookie]

IWere you being careful with your technique? Could the answer be as simple as blaming small camera movements while depressing the shutter?

I think so. I'm used to heavier cameras (I was using a 1.3 kg Olympus E-20 before that) and the 18-70 + D80 combo is quite light. I've been shooting in church with my big gun (about 2.5 kg altogether), so I am fairly certain I can exclude that.
I'm experience when it comes to the technical aspects of it, that's why I'm a bit surprised. To be fair, the lens has been used extensively (it's a used lens) and a once, a few months before the wedding, the AF was blocked.

 

[OreoCookie]

I've taken pretty pictures of letters on my wall.
So I've tried different combinations at different focal lengths and apertures. I've also varied the lighting in my room to simulate the environment at the reception. It seems to be a combination of several factors:
(1) The kit lens is quite weak at 18 mm. Even when you stop down to f6.3, the sharpness is meh. Sharpness of other focal lengths, in particular tele is very good. I've excluded jitter as a culprit by using the flash and 1/200 s. Tele shots were sharper than at 18 mm.
(2) The lens has trouble focussing with the kit lens when it's darker (also obvious, doh), the accuracy of the AF improved when I turned up the light.

Then I put on my bazooka zoom. When I inspected the pictures, it hit me: pictures can be this sharp?!? (Trust me, I have never taken pictures of my bathroom tiles to test my lenses …) Handheld shots @200 mm were pristinely sharp. At first I thought my camera had a problem as the sharpness varied across the picture a little. Then I noticed that the paper was slightly wavy! I couldn't even really see that on the other test pictures. Keep in mind that this is the one of the second-oldest AF version of the 2.8/80-200 zoom (the ED version of the push-pull zoom), so I'm sure the IQ has improved in newer generations.

Now I can rest assured that I haven't suddenly begun screwing up pictures. Or that my camera needs to be serviced, thanks guys!