Does my D70 have any focus issues?

Hi,

I have been using my D70 for a few months now and I have had good and bad results.

Whatever the results are I am aware that a certain degree of post processing is

required.

I usually use levels, curves and a bit of un-sharp mask and that?s about it,

however I feel that the images a rather blurred and have a soft, almost hazy

look about them.

I have followed a few manual set up suggestions but have never achieve the

desired results.

 

I have taken a few test shots to give you an idea of what I am talking about and

I would appreciate some comments and suggestions I could try to improve my shots.

 

http://i72.photobucket.com/albums/i178/analtwat/test2.jpg

 

http://i72.photobucket.com/albums/i178/analtwat/test3.jpg

 

http://i72.photobucket.com/albums/i178/analtwat/test1.jpg

 

I shoot mainly in aperture priority, AF-S, 250 ISO, single focus mode and I use

auto focus (AF assist is off).

Should I have the lock on ?L? or set to the dot?

I have the camera body set to AF and also the lens AF (standard Nikkor 18-70mm).

Are these settings ok? or am I counteracting something by having something on

the wrong setting?

 

Any advice would be gratefully appreciated!

 

Regards,

 

Alan

I checked your test3 image, the one with the boats. If you look at the histogram in PhotoShop, it is shifted towards the left, indicating that the image is under-exposed. I brightened it up a bit and got the corrected image below.

 

The EXIF data shows the exposure being 1/250 sec at f8 at ISO 250. Given the "sunny 16" rule, at ISO 250 and 1/250 sec, the aperture should be f16. If anything, the image should have been over-exposed by 2 stops at f8. You might want to get your camera and lens checked.<div></div>

Hi,

Thanks for that and for taking the time to alter the image.

I have just thought of 1 cause for the under exposure ? I had a circular polarizer on for the shots.

This does not explain the out of focus problem. If I am in aperture priority mode how do I know if I have the correct exposure? Under shutter priority I know I have the in camera light meter but not for the aperture priority (or am I missing a simple thing here).

 

Regards,

 

Alan

Sorry, I wasn't aware of the polarizer, which reduces the exposure by approximately 2 stops. So the sunny 16 rule checks out. There is still a bit of underexposure, though.

 

I am not aware of any obvioius focusing issues. To check that, you need to provide a crop of the center of the image at the pixel level.

 

Incidentally, for outdoor shots, the light is usually best early in the morning and late in the afternoon, when the angle of the sun is low. The shadows will give you the sense of depth in your images. However, I would try to avoid major shadow areas. For example, in test1 and 2, it is like one half of the image is in the shadows.

Try shooting without the polarizer. As these filters are quite thick they might influence image sharpness and even prevent focus to infinity.

The thing is I only just bought the CPL and images before were all slightly blurry too!

From the info above can anyone tell me what settings I may find work better?

Hi, Alan

Make a new test using this chart

 

http://www.scribd.com/doc/266756/Camera-Focus-Test-Chart

 

and post again your results.

 

Juan Parmenides

Alan you are using the kit zoom lens?

For testing sharpness I would always use a tripod, lens hood and no filter. Use manual focus to infinity. Choose a scene with the center AF sensor on a nice contrasty structure like a building to test AF. Best conditions for the D70 is a bright slightly overcast day. Set WB to automatic and use a low ISO speed. A mixed landscape with a few buildings perhaps one near person will give you images to practice your skills in post-processing and let us see if the camera and lens seem OK .-)

 

What is your software for post processing? Best to shoot RAW for testing and have all adjustment as "neutral" as possible for a start.

The D70 may seem a bit outdated but it is actually a nice camera and got a nice capable sensor. The kit lens is great for the money and excellent near f8.

Sharpness issues with the D70 and the 18-70mm kit lens.

 

First, the AF system in the D70 was originally designed for the N80, a 35mm SLR. The result of this choice is that the D70 has AF areas that are a bit too large for the DX format. This can cause the D70 to take in too much detail in the AF area. If you have detail at multiple distances within the AF area this usually results in the D70 focusing at the most distant detail. So, you have to be very careful about choosing your focus targets.

 

Second, the JPG engine in the D70 is NOT very sharp. I can nomally print my JPG files up to 11x17 inches without any sharpening. However, if I want to make a larger print I have found that it's best to shoot in the NEF (raw) format. Try comparing some JPG versus NEF images and you'll see an obvious difference.

 

Fourth, be real careful about using the Closest Subject AF mode. That one is a real "gotcha" because all of the AF areas are active in this mode and the focus will be driven by whatever is nearest to the camera. In a landscape, this means the camera will usually focus at the grass at your feet.

 

Lastly, avoid using any aperture smaller than f11 because diffraction effects degrade the images noticably.

 

I would also suggest that you try making some unaltered prints before you decide that your images are soft. When viewing images on a computer monitor at a 100% zoom level you end up looking at a fairly high magnification image. On a 17 inch monitor running at 1024x768 screen resolution this is equivalent to looking at a piece of a 24x36 INCH print.

 

Hope these tips help. The D70 is a great camera with some quirks that take some adjusting to. However, once you learn it's foibles it's capable of taking some pretty stunning pictures.

Fred Picker used a very simple method for checking focus. He would set up his camera (on tripod) and photograph a diagonal picket fence. He would put something like a handkerchief on the picket he used as his focusing target. Looking at the print would tell the tale.

 

One of the annoying "features" on the D70 is the closest object focus option. Several of the programs use it. While it is not the default on aperture priority, it would be worth checking to verify that you are indeed using single point instead of closest object.

 

I agree about testing with no filter.

 

Ken

Hi and thanks to all who responded.

I will run some more detailed tests.

I already shoot in RAW, aperture priority, AF-S and keep the ISO low.

Should I use single focus for still shots? E.G landscapes and close ups?

 

I also have it set up as sRGB is this a preferred setting?

 

Regards,

 

Alan

sRBG is fine for checking out the camera and the lens. The color space will influence the way colors are reproduced. Until you read up on color space and if your main output is the computer screen you might leave it this way. If your only or major output are prints you may want to use Adobe RGB but unless you know how to set up a color controlled workflow it will not help much. This will require a bit of studies and you may want to tackle one thing at the time :-)

Im a frustrated user of a Nikon d 70 residing in India...where we have no Nikon service centers to help us out on any case of any major issues with a camera.For years i have been blaming myself for the poor photograph outputs and kept changing lenses but nothing seemed to help.Then i came across photo.net and learnt about the backfocus issues with the nikon d 70.i tried twiddling with the AF stopper and used the focus test chart to try and improve the focus,...but it was never perfect.I need a little help from all of you gentlemen out there.Im uploading a pic taken straight out of the camera,...and posting it for u to have a look and give me a feedback as to my camera really has a focus issue or not.Im using the 18-70DX nikkor kit lens.

 

In the following pic,...i have actually focussed on the lady in the middle (single area AF) with only the middle AF sensor area.But take a look in full res,and you would notice that the camera has actually focussed on a camera a guy is holding to the right of her.Observe how sharp the focus is on the nikon cam and the black strap.also notice the sky blue sunlight shade behind the ladies which seems to be in great focus too! only the lady on whom i focussed in the middle is not in sharp focus.My question is....can it happen that my middle AF sensor may have changed position....or is it a backfocus issue?Im utterly confused....plz help!!<div></div>