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06-06-2008, 02:52 AM   #76
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Simple

Shoot on a mid-grey target with Spot metering and to see if the outcomes and results are normal.

QuoteOriginally posted by Zewrak Quote
I only see JPG's. But from what I see;

ftp://ftp2.landtrekker.org/landtrekk/pef/imgp0368.jpg
That image, if spotmetered and metering not locked, you are metering on the sand behind the kid. Camera will think you want to exposure to get the sand, and therefor lower the exposure, making the kid, that is darker then the sand, look even more dark.

ftp://ftp2.landtrekker.org/landtrekk/pef/IMGP1008.jpg
Same here, if you are spotmetering in the middle, you are metering on a WHITE t-shirt, camera will lower exposure to fit the t-shirt. Everything darker then the WHITE t-shirt will be even more darker.

ftp://ftp2.landtrekker.org/landtrekk/pef/imgp0387.jpg
See previous, but switch T-shirt, with truck

Basically, looking thru all them jpgs, its a constant that you have something white or very light somehwere in the middle of the picture, but you are trying to capture something darker. Can it be that you are metering the light areas and try to photograp the darker areas? Try locking metering on a darker surface of your motif and see if thats better.

Edit: whoops there were more pages to this thread *blush*


06-20-2008, 02:06 AM   #77
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Pentax opinion

This is the Pentax comment regarding this subject (in French):

Les photos sont certes un peu sous exposées, mais cela reste la consequence de photos qui sont faites dans des conditions extremes en terme de contraste. Les conditions d'eclairage que voud utilisez pour faire ces tests sont tres difficiles pour un capteur ou pour une pellicule. Il faudrait utiliser plutot le bouton memoire d'exposition en association avec la mesure spot. La mesure pondéré peut etre aussi tenté, mais le manuel reste sans doute la meilleur solution.

Il ne faut pas oublier, que la photo necessite aussi du Post traitement, et dans ces conditions extremes, il est presque obligatoire de passer par des logiciels de traitements photographiques, pour obtenir les plus beaux resultats, comme au temps de l'argentiques ou apres le photographe intervenait le devellopeur-retoucheur.


What I understand is that a K20D is not able to properly shoot (in automatic) these kind of "extreme scenes"...
06-20-2008, 02:49 AM   #78
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Dear mrechte:

I have gone through all your photos and most of the exchanges in this thread. Most of the exposure incionsistences are quite obviously user induced. All the technical details are from the EXIF data.

You complain about inconsistent exposures, comparing the photographs:
– IMGP1110 versus
– IMPG 1109

easy enough to explain the "inconstent" exposure: 1110 was exposed with SPOT metering and 1109 with MATRIX metering. Indeed the Matrix metering did a very good job - but spot metering was wrongly applied. YOu should have used a +1 expsoure correction for such a scene to obtain good exposure with spot metering.

So, nothing to complain about the K20, indeeed you should praise the matrix metering.

The first two images show exactly the same kind of "inconsitency":
– IMGP 0906 versus
– IMGP 0905

0905 is matrix metered and the K20 did a very good job, considering, that you shot directly into the sun! You should have used fill-flash for that, as this is the only option to balance the sign against the sky. in 0906 you used spot metering. presumably right onto the mainly white sign. So you should have applied (as in the above image pair) a +1 exposure correction, as NO meter interpretes white as white, but as 18% (or in some cases as 21 %) medium grey.

– IMGP 1008
is indeed e bit underexposed. You use matrix metering and unfortunately "hard" contrast. This obviously diminishes your expsoure latitude (like using slide film over negatives)
. It might just be, that the white shirt right in the center of the image lead to the 1/2 stop underexposure. Other cameras might have exposed brighter, but herte is a typical characteristic of the Pentax DSLR exposure system: they tent to expose carefully (= slghtly under) to prevent blown out highlights. This is much easier to correct in post-processing, than the other way round.

– IMGP 0353
you used spot metering. As the center of the image is the brighter mural painting, underexposure is the natural result. You should have corrected that too by +1 stop. Alternatively I am sure matrix metering would have given a better result – as in the above images.

– IMGP 0356
exactly the same user mistake: spot metering right onto the brightly lit WHITE area of the image. Severe underexposure is the necessary result! In this case even matrix metering wouldn't have coped with that. You need to learn to apply exposure correction in such situations with ANY camera!

– IMGP0368
spot metering again… This is an extremely high contrast scene, well beyond the contrast range a DSLR can perfectly reproduce (slide film would be equivalently "overwhelmed"). You made it worse by your "hard" contrast setting, you obviously employ as a standard preset.
A scene like that can only be remedied by using fill flash. No other way. You need to learn to expose correctly onto the background and then fill-in the foreground with balanced flash.

– IMGP 0387
shall I write "spot metering again". You measured onto the white, extremely brightly lit vehicle. Severe underexposure is to be expected. So the K20 deleivered exactly, what any other capable camera does. No need to say, that your "hard" contrast setting contributed to severe the problem. You should have dialed in at least +2-stops exposure compensation.

– IMGP 0698
it is hard to comment on this picture. It looks quite flat, despite your "hard" contrast setting and is clearly underexposed. This could be a real exposure mistake by the cammerra. BUT I don't know the sand's colour. desert sand can be blindingly bright, nearly white and if that was the case, the camera would underexpose and you should have used a +1.5 stops exposure compensation.

So, my conclusion is: Apart from two images, where the camera expsoure system might well be a contributing factor to the underexposed images (but as I don't know the original scene, I cannot decide) MOST of your images are underexposed in a matter any camera would do. This is, because you:

– did not employ expsoure correction, despite it would have been appropriate for most of the images
– did not use fill flash, which would have been the obvious choice in some images
- preset "hard" contrast for your images, which is completely inappropriate for most of the scenes here
- did use spot metering, which should only be used, if one is confident to use it properly, otherwise it will make things much worse, than using "just" matrix metering.

I would suggest, you read about the workings of exposure metering and how the scenes' contrats and brightness distribution affect metering. All in all, your images don't proof any shortcoming on the side of the camera.

regards
Ben
06-20-2008, 03:45 AM   #79
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QuoteOriginally posted by mrechte Quote
This is the Pentax comment regarding this subject (in French): [...]
What I understand is that a K20D is not able to properly shoot (in automatic) these kind of "extreme scenes"...
@mrechte:

I read french. After all the valuable input from the forum, esp. as properly summarized by the post just after yours, I wouldn't have expected this reaction from your part.

Pentax France tried to help you. They didn't go through each particular image as we did, checked EXIF etc. They gave you some general hints which could prove useful. They help you, you hit them. What kind of person are you?

You obviously made some user errors when shooting those images and just because your previous camera behaved differently you now think it is Pentax fault.

If you just want "automatic", stick to matrix metering, use D-Range and use constant +1/2 EV as you don't seem overly concerned about blown highlights.

06-20-2008, 06:08 AM   #80
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For everyone trying to help the O.P., he also posted the same comments about Pentax on a french website and seems to completely disregards people advice. To me, it seems like he thinks he is "God's gift to photography". I won't spend any more time on this thread.
06-20-2008, 06:41 AM   #81
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QuoteOriginally posted by falconeye Quote
If you just want "automatic", stick to matrix metering, use D-Range and use constant +1/2 EV as you don't seem overly concerned about blown highlights.
I would use Centre-weighted Average, applied +0.5 or +1 (or whatsoever appropriate).
06-20-2008, 07:44 PM   #82
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QuoteOriginally posted by RiceHigh Quote
I would use Centre-weighted Average, applied +0.5 or +1 (or whatsoever appropriate).
Taking a chance here, but here RH would be right, for people who kill shots with backlighting, center weighed with up to +1 would probably yield better results. Having said that, i'm still getting used to the fact that i start to trust matrix metering more than i ever trusted "evaluative" metering on the 30D.

<disclaimer>This comment is aimed at people who see the same issues with their shots and are interested in getting some pointers, not mrechte.</disclaimer>
06-21-2008, 02:39 AM   #83
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@Ben_Edict: Thank you very much for your precise review of each picture. Many people just gave general comments on pictures without reference to any particular picture. I agree with most of your explanations, if I stick to the rule about the 18% grey or so.

Having used the K20D for some time know, I would not recommend this camera for "quick shooting", especially for outdoor use.

*) Hardly readable viewfinder indications in highlights
*) No indication of the set light measure method in the viewfinder nor on the LCD screen. When one considers the implication of forgetting to reset it to multi-seg mode...
*) Too many AUTOMATIC modes
*) Useless Liveview mode
*) Multi-seg AUTO mode far from satisfactory (I would expect an AUTO mode to work without applying correction, would I not ?)
*) SPOT meter not convenient to use, setting exposure on the main subject based on 18% gray subject is not enough to get a proper exposure in most situations.
*) With the K20D one needs to apply corrections (or use manual mode) for nearly any single shot. Better not be in a hurry to take a picture.

Sorry for the Pentaxists, but it is not because I own a K20D that I will post only "oh Pentax is the best". This is like I am.

Finally I thanks all of you who spend their time on this instructive thread, that I consider now closed for myself.

Best regards

06-21-2008, 02:56 AM   #84
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QuoteQuote:
*) Too many AUTOMATIC modes
Could you elaborate? What "Automatic" modes are you talking about?

QuoteQuote:
*) Hardly readable viewfinder indications in highlights
The Canon EOS 1D Mark IIn (which I've tested) has the same "problem". Complaining about this is like complaining about viewfinder blackout when depressing the shutter.

You're being unrealistic.
06-21-2008, 04:33 AM   #85
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QuoteOriginally posted by mrechte Quote
@Ben_Edict: Thank you very much for your precise review of each picture. Many people just gave general comments on pictures without reference to any particular picture. I agree with most of your explanations, if I stick to the rule about the 18% grey or so.

Dear mrechte

Thanks for your reply. Nevertheless, I fear you simply do not understand the basic workings of ALL DSLRs. ALL of your com plaints (or at least the vast majority) applies to ANY DSLR on the market. They have nothing to do with the K20 or pentax:

QuoteOriginally posted by mrechte Quote
Having used the K20D for some time know, I would not recommend this camera for "quick shooting", especially for outdoor use.
I use the K20 along my older K10 all the time, exactly for that…

QuoteOriginally posted by mrechte Quote
*) Hardly readable viewfinder indications in highlights
This is true. Unfortunately it is also true for many other cameras, including those from the film aera. The viewfinder information usually is optimised for standard shooting conditions. Shooting against direct sunlight will "overpower" the info in most cameras.
QuoteOriginally posted by mrechte Quote
*) No indication of the set light measure method in the viewfinder nor on the LCD screen. When one considers the implication of forgetting to reset it to multi-seg mode...
But that is a point, where the K20 (and the K10) excell, compared to many other cameras: You have the info about all important settings right before your eyes, because these functions all have dedicated buttons and switches. It is a concept, which's superiority about mere LCD-info has been proven for decades. It is faster and easier to recognize!
QuoteOriginally posted by mrechte Quote
*) Too many AUTOMATIC modes
As far as my K20 is concerned, I can only recognize Av, Tv, P (and the Green P) – just a small set of automatic modes, quite typicall for cameras used by advanced useres. Any entry-level camera will have much more auto-modes.
QuoteOriginally posted by mrechte Quote
*) Useless Liveview mode
I don't find it useless: It offers a grid for levelling and you can employ magnifications of up to 8x for critical focusing. This is what I use now often for extreme tele shots (500mm or more).
QuoteOriginally posted by mrechte Quote
*) Multi-seg AUTO mode far from satisfactory (I would expect an AUTO mode to work without applying correction, would I not ?)
No, completely wrong. Any auto-mode will only work without any correction in standard situations. Most of your examples were taken in extreme lighting conditions. NO camera from NO manufacturer will work without corrections! AND on top, if you apply automatic corrections to an extend, which you obviaously find suitable, then the highlights would be blown completely.
In most of your images, employing an auto-mode + matrix metering would have given much better results, than your uninformed meddling with spot-metering.
QuoteOriginally posted by mrechte Quote
*) SPOT meter not convenient to use, setting exposure on the main subject based on 18% gray subject is not enough to get a proper exposure in most situations.
You nearly never have a true 18 % grey calibration target when yyou take photographs (unless you place a grey card somewhere in the pic). So spot metering is really a specialist tool and its successful employment needs a lot of experience and know-how. You need to learn about it.
QuoteOriginally posted by mrechte Quote
*) With the K20D one needs to apply corrections (or use manual mode) for nearly any single shot. Better not be in a hurry to take a picture.
This is true for ANY camera on the market, given the image examples you provides!

QuoteOriginally posted by mrechte Quote
Sorry for the Pentaxists, but it is not because I own a K20D that I will post only "oh Pentax is the best". This is like I am.
No reason for excuses. Any camera has its limitations and shortcoming. The K20 is no exception! BUT the case you made was largely ill-advised, as most errors are user-induced and NO camera can correct user-error.

regards
Ben
06-21-2008, 07:34 AM   #86
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... He really sounds like some friend of mine who just jump from P&S to DSLR...
06-21-2008, 07:40 AM   #87
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QuoteOriginally posted by mrechte Quote
Having used the K20D for some time know, I would not recommend this camera for "quick shooting", especially for outdoor use.

*) Hardly readable viewfinder indications in highlights
It's a bit difficult to read, but still readable. In fact, it is the best Pentax SLR for the readability already, owing to the large fonts.

QuoteQuote:
*) No indication of the set light measure method in the viewfinder nor on the LCD screen. When one considers the implication of forgetting to reset it to multi-seg mode...
A minor thing. You need to check it on the body anyway. My Canon 5D does not show the metering mode neither in the finder.

QuoteQuote:
*) Too many AUTOMATIC modes
Not really, the K200D and other entry level DSLRs of other brands have far more. Those modes exist in the K20D won't hurt anyway. But of course if Pentax can simply it, that would be great, e.g., TAv mode is not necessary - auto iso in manual mode would do it. Also, Sv mode is redundant IMO.

QuoteQuote:
*) Useless Liveview mode
Yes, agreed. Whilst it's mostly lame when compared anything else on the market, I think least is better than none! ;-)

QuoteQuote:
*) Multi-seg AUTO mode far from satisfactory (I would expect an AUTO mode to work without applying correction, would I not ?)
Yes, I agree your viewpoint. Auto mode *should* be *foolproof*.

QuoteQuote:
*) SPOT meter not convenient to use, setting exposure on the main subject based on 18% gray subject is not enough to get a proper exposure in most situations.
Yep. That underexposure thing of the Spot mode of Pentax DSLRs has being bugged me for years! See my homepage for details..

QuoteQuote:
*) With the K20D one needs to apply corrections (or use manual mode) for nearly any single shot. Better not be in a hurry to take a picture.
You miss many photo opportunities if so.

QuoteQuote:
Sorry for the Pentaxists, but it is not because I own a K20D that I will post only "oh Pentax is the best". This is like I am.
Yes, I think you're right on this. But every user can make his own different opinions anyway.
06-21-2008, 06:33 PM   #88
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QuoteOriginally posted by Ben_Edict Quote

But that is a point, where the K20 (and the K10) excell, compared to many other cameras: You have the info about all important settings right before your eyes, because these functions all have dedicated buttons and switches. It is a concept, which's superiority about mere LCD-info has been proven for decades. It is faster and easier to recognize!

regards
Ben
Could i have picked one up in a store and checked the ergonomics out instead of online window shopping, i had never taken that long to buy my K20D.

I can do a whole lot more with this camera that does not require me to take the eye from the viewfinder than i could with my previous camera.
06-21-2008, 06:47 PM   #89
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The OP abandoned the thread several posts up - we should too and move on to something useful.
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