poss. Ds meter problem

Looks like I have a metering problem with my new Ds, all my images seem to be approx 1.5 stops under exsposed when compared to my chums D70 pics taken same day same time. I have taken a couple of grey card readings/pics today and the peak of the histogram on the images is one division left of the centre, if I EV compensate 1.5 the histogram is central and my images apear to my eye to be about right. Am I on the right track ? has anyone out there had simillar problems ?

If that makes the pictures what you want them to be, then that's about right!

But it all depends on the metering method, the exact framing, and there is no guarantee that the picture your friend was taking didn't have a different distribution of tones, or a different metering pattern. To really compare, both cameras would have to be set up in a tightly controlled way.

Then there is the interpretation of the histogram. If the picture was full of dark tones, then it would be correct for the histogram to be shifted into the area of darker tones.

In the end, if you get the results you want then you don't really have a problem.

Thanks John, the problem I seem to have is I am finding that I'm having to compensate EV 1.5 approx. in each of the three metering modes to obtain what I consider to be the correct exposure. I am then left with only 0.5 if I wish to over expose. Am I correct in thinking that what the camera deems as the correct exposure should be EV 00, thus allowing me two stops either side to under or over expose.

If you were photographing a mid-grey wall then everything would be neatly displayed on the histogram, but the real world is not like that....

Over-exposure on a DSLR is about the last thing we need if we want to avoid totally blown out highlights. Under-exposure is preferable and can be adjusted in Photoshop (within reason).

If you are having exposure problems, there are lots of good books that cover the subject, and a thorough understanding is very helpful.

You could test the accuracy of your meter in a fairly accurate way by using the "Sunny 16" rule. On a bright, full daylight day a fully illuminated subject should record an exposure of f16 at the reciprocal of the ISO speed. So at 200 ISO that would be f16 at 1/200 sec. I know this isn't ultra-accurate, but it is surprisingly spot on much of the time and it might help you to ascertain if you do have a significant exposure error.

I wonder if the *istDS and the D70 were set to the same ISO speed?

It's a complex subject, so I hope all that was helpful rather than confusing!

Cheers John, not confusing, Re: the d70 we were both using c/w metering and thw same ISO. Today i was photographing a grey card, and hence my comments regarding the histogram, which coupled with the under exposed problems led me to believe the meter is giving me a false reading.

hi,
There is a serious flaw with the camera on underexposure which I posted on another forum and they did not like it and said it was me.
I have two digis an 0lypmus e 10 and the d.
Taking two indentical shots the d is up to 2 stops under exposed
bryan

Either you are doing something wrong, or you have a faulty camera. Take it back to where you got it from, and ask them to fix or replace it.

There's nothing anybody here can do to help you, other than to advise you to check that you are doing everything correctly.

G

Hi George,
It is not my single camera that is wrong but many many postings have been made regarding this problem which points to a firmware prog within the camera.
As an above post mentioned, 1.5 compensation is being made to obtain a decent exposure and I`ve learned to live with it and do the same.
It is too much of a coincidence that so many people have this problem.
Compared to the oly, I used a gray card/ spot meter and same light/ distance etc and the D was under exposed, the oly was spot on
Bryan

I have to say that I have no exposure problem with my *istDS - all the exposures have been spot on, as has the AWB. So I don't think it can be a firmware problem.

Hi everyone again and thanks for your comments, had a nice sunny 1/125 f16 day in Norfolk yesterday - reset custom function on the Ds just in case I had made a mistake in any of the settings and took some shots in auto-pic and in my opinion they all reqd. approx 1 to 1.5 compensation to give a decent image. I have just been into my retailer, they agree and are going to obtain another body to compere ( they did also sugest that Pentax digital tend to err on the underexpose compared to Nikon and Cannon, any thoughts anyone ?)

Hi,
Thank you.
I`m convinced that the first D that came out had these problems , but was addressed with the launch of the next camera.
It doesn`ts pay to be an early odopter
Bryan

Further investigation seems to show that there is, relatively speaking, less exposure given when using M series lenses. Whether this is 1.5 stops I wouldn't like to say, but the histogram definitely shifts to the darker end. However, images still perk up nicely after a levels adjustment and at least we don't get burnt out highlights.

What lenses were being used?

Interesting.

I have 100mm 2.8 lenses in both M and FA macro versions, and 28mm 2.8 in both M and F.

I have placed the camera (*ist D) on a tripod in the kitchen, and shot with all four lenses using ambient light on manual with the aperture set on f5.6 on the lens. I then pressed the green button to set the exposure.

These are the recorded shutter speeds:

M 28 1/3.3
F 28 1/5 (Definitely looks slightly under-exposed)
M 100 1/2
FA 100 1/3.3


I was using spot metering, so I tried again with matrix, but pointing in a different direction, with less light:

M 28 1/8
F 28 1/10
M 100 1/5
FA 100 1/10

and finally with centre-weighted:

M 28 1/8
F 28 1/10
M 100 1/6
FA 100 1/13 definitely under-exposed

All exposures were acceptable (except for the two marked otherwise), though always slightly on the under-exposed side. This is perhaps understandable given the preponderance of bright white surfaces in the kitchen.

So from this brief test it seems that the camera tends to under-expose more with AF lenses than with M lenses. This is completely opposite from JR's experience.

I have to say that in practice I haven't been conscious of any exposure problens, though I do always adjust levels in the computer. I usually shoot Jpeg and I usually use Irfanview for adjustments (because it's so quick), unless the picture requires the extra muscle of Photoshop.

G

Hee hee, just to add to this (when using the *ist-D)... I find the SMC-F 50/1.7 is always a tad over exposed, and setting an underexposure of -0.5 to -1.0 is helpful.

Additionally, I read somewhere that when the M series are used there is no matrix metering (ie the lenses without the electrical contacts). So maybe that explains the problem John is experiencing.

The link is here: http://www.robertstech.com/matrix.htm
(Makes for some interesting technical reading )

Matt

Hi all, me again, seem to started something here. Reff the last note from George, after playing at the weekend images from my old M lenses apear to be slightly better in my opinion than those taken with the 18-55 DA lens that came with my DS (this is the only auto lens I have) . Still waiting to try another body, but reading your coments I dont expect to see much difference.