Reading mode: Light Dark

Thom's remark on limits of MM and luminosity

Go to last post
When I use to shot with my Nikons analog camera I believe MM was better then what it is now. I hardly ever had overexposed pics.
 
"The limitation is a Program exposure mode thing. I don't believe it is operative in other exposure modes, but I'm still checking."

So, he'll likely be back to it, and I'll check my D80 if in, say, A or S modes and MM, it has the limitation as the manual says for P mode.
Graystar said:
win39 said:
I think it has something to do with the mapping of the matrix. The 16.33 EV has to do with the middle value in the scene. You still need higher values in the matrix to measure the highlights.

Put another way, if the maximum value were not limited below the maximum you would not have light measurement inputs from the highlight portions of the picture. The whole point of the matrix is to measure the brightest and darkest parts of the scene and to assign an overall weight. That overall has to be set below the maximum of the meter EV scale or it cannot map the brighter portions.
Click to expand...
I'd buy that.

.
Click to expand...
--
Renato.
http://www.flickr.com/photos/rhlpedrosa/
OnExposure member
http://www.onexposure.net/

Good shooting and good luck
(after Ed Murrow)
 
I can only speak for the D90, but I've already checked all the modes and it's a Matrix thing...not a P-mode thing. Even in M mode, the meter won't read more than 16 EV at ISO L 1.0. I can have my D90 pointed at the sun, and the meter in M mode will read zero at f/11 and 1/500s. I then switch to spot or center and the meter shoots to the + side.
rhlpetrus said:
"The limitation is a Program exposure mode thing. I don't believe it is operative in other exposure modes, but I'm still checking."

So, he'll likely be back to it, and I'll check my D80 if in, say, A or S modes and MM, it has the limitation as the manual says for P mode.
Click to expand...
.
 
Graystar said:
I can have my D90 pointed at the sun, and the meter in M mode will read zero at f/11 and 1/500s. I then switch to spot or center and the meter shoots to the + side.
Click to expand...
Was the sun filling the frame? If not, the less bright areas may be influencing the reading in matrix.
 
binary_eye said:
Graystar said:
I can have my D90 pointed at the sun, and the meter in M mode will read zero at f/11 and 1/500s. I then switch to spot or center and the meter shoots to the + side.
Click to expand...
Was the sun filling the frame? If not, the less bright areas may be influencing the reading in matrix.
Click to expand...
I would need a 2000mm lens to have the sun fill the frame. I used my 18-105mm at 105. The sun was in the center of the frame and small...probably too small to spot measure. Still, it was so bright that in Center Weighted it was still two stops too bright at f/11 and 1/4000s. Switching to Matrix at 1/4000s causes the meter to read more than 2 stops underexposed. The meter is centered when shutter is dropped to 1/500s. This is on a tripod.

.
 
Graystar said:
I would need a 2000mm lens to have the sun fill the frame.
Click to expand...
Yeah, I guess that was a pointless question. Just wondering if an evenly lit surface that fills the frame such as a white wall in full sun, or even a piece of white paper, would be a better test subject.
 
binary_eye said:
Graystar said:
I would need a 2000mm lens to have the sun fill the frame.
Click to expand...
Yeah, I guess that was a pointless question. Just wondering if an evenly lit surface that fills the frame such as a white wall in full sun, or even a piece of white paper, would be a better test subject.
Click to expand...
It probably would be better if it can be made bright enough. But even sunlight falling on a white paper isn't bright enough.

And I actually have a 1500mm "lens" in the form of my telescope. I attach my D90 to it for astrophotography...but I'm not going to risk shining a 5-inch mirror full of sun at my sensor! There are more than a few stories in the astronomy forum of smoking telescopes and car fires started when a scope ended up accidentally pointing at the sun.

.
 
No he did NOT! That is what YOU read into it. I converse with Thom often - about many things. By the way, it doesn't look like (from your posts) you even OWN a D7000.
Graystar said:
Steve Bingham said:
Graystar said:
All you have to do is test it yourself.
Click to expand...
But of course I did! Is that the sum of your evidence?
Click to expand...
Yes it is. Test it again...this time, correctly. If it still seems to work then take it up with Thom Hogan...he's the one who raised this point.

.
Click to expand...
--
Steve Bingham
http://www.dustylens.com
http://www.ghost-town-photography.com
 
BackInTheGame said:
You seem a serious person. If you don't mind, please tell me what you are seeing without all the slurs about Nikon camera design. I'm loyal to them for one reason, they have always delivered, and I simply don't trust anything else. If that makes me a fan boy, so be it.
Click to expand...
I don't know where you see any slurs from my part, I hold Nikon's camera design's in very high regard. I blindly recommended the D7000 to two people based on my personal very positive experience with the D200, and the D90's immense popularity. I thought the D7000 would be a no-brainer. I admit now that did in fact recommend it prematurely, not holding a D7000 myself at the time, but I felt I could do that owing to my past experiences and Nikon's excellent reputation.
Member said:
But If I can find out something from you pertaining to the camera I'm interested in, I would appreciate it. I have it on order, and I already know how to return it, but at this point I doubt seriously I will. I do know I will probably sell it when the D400 comes out, but for this nesting season in southern Louisiana I'm going to give it a go. I do have a fall back.

So what kind of scenes are metering wrong? Is it more highlight related or shadow related? If you can give me specifics I can know what I need to adjust for. What adjustments, I don't know yet, whether it be compensation or another metering mode. But I would appreciate a measured sensible response, and I will answer any question you might have for me in the same manner. And if you have any comments about focus tracking, I listening.

And I honestly don't care if Nikon does a firmware change because I will just go through the same exercise again. It's the part I enjoy because I get it wrong more than I get it right. Kinda like a crossword you can never quite finish.

I'll let you write what you wish without comment for people looking at this thing a different way.
Click to expand...
I agree with the review sites that Matrix-Metering on the D7000 will blow out uniformly bright scenes, and I have no reason to doubt Thom Hogan's very lucid explanation for it. I know my way around a camera and can easily compensate for the idiosyncrasy, but that's not the case for the people I recommended the camera to, and I fear, for the thousands of people who will buy this heavily marketed, relatively affordable enthusiast camera.

Putting a perpetual - EV isn't the solution, because the meter seems to work fine in every other case, it's just uniformly bright scenes where it gets capped. P mode and Matrix Metering is the one mode I sense this particular level camera will be used in the most, and it bothers me that a bright sunny day is all it takes to challenge a new user (and my recommendees). it already has been for big review sites, including this one.

As good as this camera is, I'm sure the D400 will be even better, and this "Auto-ETTR" or "tone optimized" metering as some are calling it makes much more sense at that level. I'm glad I know more about the esoterics of a camera more than a newcomer, but it doesn't make me feel better recommending a D7000 (or a even a D3100 now) with a caveat, or worse, telling them they have to learn "real photography" before enjoying them.
 
It would be interested to do your "Sun" experiment and do it with comparable cameras from different manufacturers and see the results. My guess is the majority will suffer from some exposure innacuracies of some kind. Probably different than your D90, but innacurate all the same. That is a tough exposure for any meter to nail.
--
Quote: Experience is simply the name we give our mistakes
Oscar Wilde
 
Same for D80, all modes, auto, P, S, A with MM will top at f/8+1/1000s = f/11+1/500,s so it's not f/7.1+1/500 as Thom mentions.

I shot a piece of aluminum reflecting full sunlight, spotmetering read f/11+1/4000s to center exp dial, ISO 100, MM would to at 1/1000s+f/8.

Then I checked how the landscape would meter to preserve HLs in the clouds and some bright white wall in full sunlight, at ISO 100, f/7.1 + 1/500s was about perfect exposure, no clipping, bright areas just nearing right en of histogram. And MM nailed it right on.

Thus, for all practical purposes, maybe except snow in full sunlight, the limit Nikon uses for MM is good enough, there are about 2 1/3 stops still left from typical bright scene and limit (1/500+f/7.1 to 1/1000+f/8).
Graystar said:
I can only speak for the D90, but I've already checked all the modes and it's a Matrix thing...not a P-mode thing. Even in M mode, the meter won't read more than 16 EV at ISO L 1.0. I can have my D90 pointed at the sun, and the meter in M mode will read zero at f/11 and 1/500s. I then switch to spot or center and the meter shoots to the + side.
rhlpetrus said:
"The limitation is a Program exposure mode thing. I don't believe it is operative in other exposure modes, but I'm still checking."

So, he'll likely be back to it, and I'll check my D80 if in, say, A or S modes and MM, it has the limitation as the manual says for P mode.
Click to expand...
.
Click to expand...
--
Renato.
http://www.flickr.com/photos/rhlpedrosa/
OnExposure member
http://www.onexposure.net/

Good shooting and good luck
(after Ed Murrow)
 
I am going to take 13 members of my photo club for a photo shoot Sunday. We all have DSLR's. Canons, Sony's. Olyimpus etc. All very good equipment and most of these people are very experienced phtotgraphers.

I called them asking if they would do some real world testing doing some shooting of very high to moderely high secenes that possess very bright skies and shoot them in matrix 1st and then test the other modes accordingly.

I will post the results after xmas or sooner if possible. I have family coming so I am not sure of the time available.

Meanwhile this is another experiement I am going to do with the Nikon cameras. I have never tried it, but it looks intruiging.

Have a read. It was a post on another thread. It also links to the Nikon Cafe's original article.

QUOTE ( with thanks to Dayd3 ) :

Dayd3 wrote:
I explored a little bit more Matrix metering on D80 and found some
tip on the web how to use this metering in a way which is NOT
MENTIONED ANYWHERE IN NIKONS USER-MANUALS.

We all agree that Matrix Metering try to protect shadows which very
often finishes in blown out highlights if under our focus point is
something darker than middle gray. While sometimes we want such a
behaviour many times we don't. We also know that by default metering
doesn't lock when shutter is half pressed AE LOCK - off (CSM 19).

But what I didn'rt realize before is that MM also takes two metering
and averages them. For example if we focus on someone's face, half
press shutter and than recompose, instead of simply taking a new
reading camera will average the original exposure and the new one.

If we combine this behaviour with a AE-L/AF-L set to AE Lock Hold or
AE Lock Only (CSM 19) we can actually focus where we like by half
pressing shutter button and holding it (camera focuses and takes
first reading) than we point camera for example to the sky and press
AE-L/AF-L button (or press and hold what depends on our settings CSM
18). Than we recompose again and take picture. In this way MM can
average readings from the darkest and lightest subject and prevent
blown out skies.

This is working only in Matrix metering mode and it seems doesn't
work in AF-C mode.

Link to web page where I found this tip:
http://www.nikoncafe.com/vforums/showthread.php?t=95098

UNQUOTE

--
Quote: Experience is simply the name we give our mistakes
Oscar Wilde
 
rhlpetrus said:
Thus, for all practical purposes, maybe except snow in full sunlight, the limit Nikon uses for MM is good enough, there are about 2 1/3 stops still left from typical bright scene and limit (1/500+f/7.1 to 1/1000+f/8).
Click to expand...
Likely why this has never been an issue until Thom mentioned it. :p

Eh...MM tends to underexpose snow anyways. ;)

.
 
I'll send him a note about that. Thanks for participating in the debate, I think this is now pretty much understood and I just don't see it as an issue.
Graystar said:
rhlpetrus said:
Thus, for all practical purposes, maybe except snow in full sunlight, the limit Nikon uses for MM is good enough, there are about 2 1/3 stops still left from typical bright scene and limit (1/500+f/7.1 to 1/1000+f/8).
Click to expand...
Likely why this has never been an issue until Thom mentioned it. :p

Eh...MM tends to underexpose snow anyways. ;)

.
Click to expand...
--
Renato.
http://www.flickr.com/photos/rhlpedrosa/
OnExposure member
http://www.onexposure.net/

Good shooting and good luck
(after Ed Murrow)
 
rhlpetrus said:
Thom, in his D7K review, wrote this about the MM system of D7K:

"Be aware of one very big caveat: when the scene you're metering hits 16.3 EV, the matrix metering system gives up and sets its value for 16.3 EV, no matter how much more light there may be. EV 16.3 at ISO 100 is f/11 at 1/500, which is barely beyond Sunny 16."
Click to expand...
This is a bit OT, regarding the D7000 metering -- but I have to say I'm a little disappointed in the technical sloppiness of Thom's EV calculations you quoted. EV 16.3 is 1/640s at ISO 100 and f/11 (not 1/500s). And that's 1.7 EV (3.2 times) brighter than "Sunny 16", which is EV 14.6. I'd hardly call that "barely beyond".

Okay now, back on topic ... :)
--
Greg
 
Matrix Metering is the only metering mode that does not do an average of pixels in a single area. Matrix metering has to send an average from each zone in the frame, the built in processor does a comparison to the matrix zone picture data bank and decides what the overall exposure is. Nikon and probably the other manufacturers that do a true matrix as well have decided that 16.3EV is the highest you can go for the_average_ exposure and still get data from the brighter zones in the picture which may approach 20EV. Without those higher values, matrix comparison will not work. Think about it. If your camera matrix sees 20EV for half the scene and lower values for the other half, it is going to set a lower value.

I live near the beach on the sunny coast. Matrix metering works fine on hot sunny days in the sand for me despite what Tom says. White Sands, New Mexico, may be a different matter. Then you are going to have to be more careful.

Has everyone forgotten the reason for the histogram? No shot discipline to check your exposure in potentially dicey situations and make an adjustment?
 
I and Graystar tested D90 and D80. Limit is 1/1000s and f/8 = 1/500 and f/11, camera won't go beyond that, I checked it, and it works for all modes (except manual of course) and MM. I used a metallic object reflecting full sunlight, spot centered at 1/4000s and f/16, so plenty of light for MM to go beyond that limit.

Anyway, 1/500 + f/11 still more than a stop over sunny 16. I then checked a very bright scene outdoors, with full sun, white clouds and white walls, and that was metered at f/7.1 and 1/500, so exactly at sunny 16, with very good results. I think people that care much about thei exposure should use Manual + Spot, if not, it seems MM is still pretty capable of doing right (if AF point is used right, which DPR still haven't learned to do after all these years ;) ).
copejorg1 said:
rhlpetrus said:
Thom, in his D7K review, wrote this about the MM system of D7K:

"Be aware of one very big caveat: when the scene you're metering hits 16.3 EV, the matrix metering system gives up and sets its value for 16.3 EV, no matter how much more light there may be. EV 16.3 at ISO 100 is f/11 at 1/500, which is barely beyond Sunny 16."
Click to expand...
This is a bit OT, regarding the D7000 metering -- but I have to say I'm a little disappointed in the technical sloppiness of Thom's EV calculations you quoted. EV 16.3 is 1/640s at ISO 100 and f/11 (not 1/500s). And that's 1.7 EV (3.2 times) brighter than "Sunny 16", which is EV 14.6. I'd hardly call that "barely beyond".

Okay now, back on topic ... :)
--
Greg
Click to expand...
--
Renato.
http://www.flickr.com/photos/rhlpedrosa/
OnExposure member
http://www.onexposure.net/

Good shooting and good luck
(after Ed Murrow)
 
You must log in or register to reply here.

Keyboard shortcuts

f
Forum
m
My threads
Mobile site
About
Editorial content
Cameras & Lenses
Community
All content, design, and layout are Copyright © 1998–2025 Digital Photography Review All Rights Reserved.
Reproduction in whole or part in any form or medium without specific written permission is prohibited.
When you use DPReview links to buy products, the site may earn a commission.
©GPS Media - Guides, Products, Services.
Back
Top