Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
01-27-2008, 09:41 PM   #1
Senior Member




Join Date: Dec 2007
Location: Kitakyushu
Posts: 186
Preview k20d at Trusted Reviews

Sorry if it has already been posted. Some of these samples I havent see before.Pentax K20D Hands On Preview - TrustedReviews

01-28-2008, 02:46 AM   #2
Senior Member




Join Date: Jun 2007
Location: Amsterdam
Posts: 190
[quote]
One welcome improvement is the new 11 point AF with 9 cross sensors. In conjunction with the new standard smc PENTAX-DA 18-55mm F3.5-5.6 AL II zoom, the AF speed and accuracy shows an improvement over the previous models. However, again, the camera fails to match the AF specification of rivals such as the Nikon D300 and Canon EOS 40D.[/quote

Is a quote from the 'preview'.
What's the truth ? Is it really new ?
01-28-2008, 04:19 AM   #3
Veteran Member
lol101's Avatar

Join Date: Jul 2007
Location: Garennes sur Eure France
Photos: Gallery
Posts: 900
[QUOTE=Priyantha Bleeker;164616]
QuoteQuote:
One welcome improvement is the new 11 point AF with 9 cross sensors. In conjunction with the new standard smc PENTAX-DA 18-55mm F3.5-5.6 AL II zoom, the AF speed and accuracy shows an improvement over the previous models. However, again, the camera fails to match the AF specification of rivals such as the Nikon D300 and Canon EOS 40D.[/quote

Is a quote from the 'preview'.
What's the truth ? Is it really new ?
No, it has been this way since the *istD.

The quote saying that the metering consistently underexposed by 1EV is also a bit strange... did they only try the camera indoor or what?
01-28-2008, 04:59 AM   #4
Pentaxian




Join Date: Sep 2006
Location: Kaunas
Posts: 1,452
QuoteOriginally posted by lol101 Quote
The quote saying that the metering consistently underexposed by 1EV is also a bit strange... did they only try the camera indoor or what?
Not strange. That Russian guy who wrote his impressions about trying K20d in dubay also pointed out very unreliable metering, +/- 1 EV in very simple lighting situations.

It seems that AF and metering systems will constantly be in "Cons" list of K20D reviews...

01-28-2008, 05:03 AM   #5
Senior Member
fishy's Avatar

Join Date: Aug 2007
Location: Brussels
Photos: Gallery
Posts: 199
QuoteOriginally posted by Edvinas Quote
Not strange. That Russian guy who wrote his impressions about trying K20d in dubay also pointed out very unreliable metering, +/- 1 EV in very simple lighting situations.

It seems that AF and metering systems will constantly be in "Cons" list of K20D reviews...
Wouldn't that be a relatively easy fix in firmware?
On my k10D I preset a +0.7 EV correction when on high iso only.. Normally it seems to expose just fine... (but I shoot RAW only)
01-28-2008, 06:57 AM   #6
RaduA
Guest




For me is pretty obvious that Pentax is in a race against the time. The whole Dubai thing was a little too early I guess and this is why they gave the "ordinary" kit lens maybe to create a larger depth of field and correct some autofocus issues by that. But this also degraded the quality of many pictures. Anyway IMO between most of the Dubai samples (18-55 II, v0.2 firmware, not many professional photographers amongst the jurnos) and the samples provided by Mr. Kanarek (DA 35 macro, v0.39 firmware, professional photographer) the differences are enormous. I really think that Pentax is on to something with this camera and I also think that K20D will shine with good glass on it only.
Radu
01-28-2008, 07:42 AM   #7
Veteran Member
lol101's Avatar

Join Date: Jul 2007
Location: Garennes sur Eure France
Photos: Gallery
Posts: 900
QuoteOriginally posted by fishy Quote
Wouldn't that be a relatively easy fix in firmware?
On my k10D I preset a +0.7 EV correction when on high iso only.. Normally it seems to expose just fine... (but I shoot RAW only)
Exactly my experience, +0.7/+1 in low light, 0 anywhere else, hence my confusion...
01-28-2008, 07:56 AM   #8
Veteran Member
jeffkrol's Avatar

Join Date: Sep 2006
Location: Wisconsin USA
Photos: Gallery
Posts: 8,435
No fear, it looks "normal"

QuoteOriginally posted by fishy Quote
Wouldn't that be a relatively easy fix in firmware?
On my k10D I preset a +0.7 EV correction when on high iso only.. Normally it seems to expose just fine... (but I shoot RAW only)
Too many Canon-centric journalists out there (and Canon's liberal use of fudging iso.
Canon's "fudge" puts "neutral grey at 126ish, the urban legend number of meter calibration ).
OK, meter 101 as I have spent a few years trying to understand... Pentax meters "magic number" is 110(And as far as I know most Nikons and other brands besides Canon). That is the "medium grey" number in RGB color space as used in the jpgs.
As you can see from the image the meter averaged the scene to approx 110 (see histogram).
since tones are probably evenly spread out over the "matrix" I doubt that there is a "dubai cloudy sky" LUT to compare it to so it did it's best to hit the 110 average. Maybe even center-weigt or spot metered (which should have produced approx the identical exposure, in other words metering method would not change th exposure much in THIS composition).
The camera did fine, the photographer dorked it.

MINOR correction (approx .1sec in photo editor)

IF you want to nit-pick, the meter may be "off" 1/4 stop... (In the middle of the histogram 40 "points" is roughly a stop). Again the photographer was "off" a full stop, NOT the camera...UNLESS you want it to do ALL the thinking for you

01-28-2008, 09:00 AM   #9
Senior Member
fishy's Avatar

Join Date: Aug 2007
Location: Brussels
Photos: Gallery
Posts: 199
Thanks for the tutorial!

I guess I am more of the digital age, but would like to read up on my "metering 101". Any good links to start out?

As for exposure metering, I always understood that (spot metering as I normally do) the camera will try to make what you meter 30% grey... So meter on a surface that's approx that, and shoot, or meter on white but increase exposure (or black and decrease (or anywhere in between and use judgement (caution; judging is dangerous))).. but that is indeed a different story.

If that is what's going on, no amount of firmware genious will help

Although I wouldn't mind the camera to do ALL the thinking.. And maybe my laundry?
01-28-2008, 09:31 AM   #10
Veteran Member
jeffkrol's Avatar

Join Date: Sep 2006
Location: Wisconsin USA
Photos: Gallery
Posts: 8,435
QuoteOriginally posted by fishy Quote
Thanks for the tutorial!

I guess I am more of the digital age, but would like to read up on my "metering 101". Any good links to start out?

As for exposure metering, I always understood that (spot metering as I normally do) the camera will try to make what you meter 30% grey... So meter on a surface that's approx that, and shoot, or meter on white but increase exposure (or black and decrease (or anywhere in between and use judgement (caution; judging is dangerous))).. but that is indeed a different story.

If that is what's going on, no amount of firmware genious will help

Although I wouldn't mind the camera to do ALL the thinking.. And maybe my laundry?
Actually, I always wanted Pentax to do 2 things 1)Allow me to set the meter "grey point" 2a) allow me to dial in the RGB coefficients 2b) Allow import of "custom curves" like Nikon.....Neither of which they seem to ever considered.....
As to tech specs see Thom Hogan, doug Kerr, Bob Shell ect..
Meters Don't See 18% Gray by Thom Hogan
Articles by Doug Kerr
Amazon.com: The Hand Exposure Meter Book: Books: Martin S. Silverman,Gerald Hisrchfeld,Bob Shell,Jim Zuckerman
DPanswer: Digital Zone System Tutorial
There are a lot more if you need them.............
And my favorite quote...................
'The exposure meter is calibrated to some clearly defined standards and the user needs to adjust his working method and his subject matter to these values. It does not help to suppose all kinds of assumptions that do not exist.'

Erwin Puts

http://www.adobe.com/digitalimag/pdfs/linear_gamma.pdf

Last edited by jeffkrol; 01-28-2008 at 08:11 PM.
01-28-2008, 03:00 PM   #11
Veteran Member




Join Date: Dec 2006
Location: Copenhagen
Photos: Gallery
Posts: 1,845
QuoteOriginally posted by jeffkrol Quote
Too many Canon-centric journalists out there (and Canon's liberal use of fudging iso.
Canon's "fudge" puts "neutral grey at 126ish, the urban legend number of meter calibration ).
OK, meter 101 as I have spent a few years trying to understand... Pentax meters "magic number" is 110(And as far as I know most Nikons and other brands besides Canon). That is the "medium grey" number in RGB color space as used in the jpgs.
As you can see from the image the meter averaged the scene to approx 110 (see histogram).
since tones are probably evenly spread out over the "matrix" I doubt that there is a "dubai cloudy sky" LUT to compare it to so it did it's best to hit the 110 average. Maybe even center-weigt or spot metered (which should have produced approx the identical exposure, in other words metering method would not change th exposure much in THIS composition).
The camera did fine, the photographer dorked it.

MINOR correction (approx .1sec in photo editor)

IF you want to nit-pick, the meter may be "off" 1/4 stop... (In the middle of the histogram 40 "points" is roughly a stop). Again the photographer was "off" a full stop, NOT the camera...UNLESS you want it to do ALL the thinking for you

Thanks for your run-through on metering 101, didnít understand it all; but then there is a lot in photography that I can improve on
Since there was a big sky, albeit cloudy, and the photographer wanted to catch the right colour and exposure of the tower; he should have dialled in some EV ?
Or could it have helped to Spot-meter of the building ?

Your corrected image looks great, BTW.
We donít know what Iso it was taken at ?


I guess things have been going very fast, writing these reviews; though some of the leading reviewers in the world were invited. There has been little time to PP the images. Besides, it was unknown how many of the images Pentax would allow, since it was a pre-production model.
01-28-2008, 03:14 PM   #12
Veteran Member
mattdm's Avatar

Join Date: Feb 2007
Location: Boston, MA
Photos: Gallery
Posts: 2,964
QuoteOriginally posted by Jonson PL Quote
Since there was a big sky, albeit cloudy, and the photographer wanted to catch the right colour and exposure of the tower; he should have dialled in some EV ?
Or could it have helped to Spot-meter of the building ?
Exactly -- either one of these.
01-28-2008, 03:33 PM   #13
Veteran Member
jeffkrol's Avatar

Join Date: Sep 2006
Location: Wisconsin USA
Photos: Gallery
Posts: 8,435
QuoteOriginally posted by mattdm Quote
Exactly -- either one of these.
Please note: If you spot meter on the building, and it is white, and you want it white you have to add approx +2EV exposure compensation. Otherwise it will be grey again
Same w/ snow or anything white. Best to keep it at +1-1.5 though and tweak later.
as to the edit. You see the orig. histogram is all bunched up in the middle (basically low contrast). Increasing the white and black point just spreads the remaining values out and really just increases contrast. Not really an exposure boost per se but the results are similar. Best to do in a RAW editor or w 16bit Tiffs. Keeps the holes in the histogram smaller(all the spikey things and dips).
As to Canon or iso, their sensors are underrated. An iso of 100 is really more like 125 When you expose at 100 but it is really more sensitive than that you get "brighter" exposures.
Technically it's cheating but it looks "better"................. The only way the reviewers would know it was 1 stop under was to "play" w/ the image in an editor (or make (inaccurate)judgements based on their expectations). Hanging around here you'll get used to this dark stuff..... Old habits die hard.
Sensitivity of 40D: Canon EOS 40D/30D/20D/10D Forum: Digital Photography Review

Last edited by jeffkrol; 01-28-2008 at 03:51 PM.
01-28-2008, 05:05 PM   #14
Veteran Member




Join Date: Dec 2006
Location: Copenhagen
Photos: Gallery
Posts: 1,845
QuoteOriginally posted by schufosi777 Quote
Sorry if it has already been posted. Some of these samples I havent see before.Pentax K20D Hands On Preview - TrustedReviews
Thanks for the link, BTW. That 3200 Iso shot, sure looks nice. This would make Iso 1600 useable for many appliances.


And thanks to jeffkrolís additional info on exposure, I had heard about the Canon way of doing things and that Technically they were tweaking their settings. And followed the discussion and heated debate on the Canon forums regarding the Eos 40D and Eos 30D.
I have continuously heard positive things about the Pentax metering, from the experienced users. I guess Pentax maybe follow a more conservative way, from the old light meter days.
01-28-2008, 07:12 PM   #15
Veteran Member
mysterick's Avatar

Join Date: Oct 2006
Location: 44266
Photos: Gallery | Albums
Posts: 428
This type of thread certainly trumps the negative discussions on some others. Thanks to all!!!
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
k20d, pentax news, pentax rumors, preview
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
K20D Preview Super A Pentax DSLR Discussion 3 12-06-2009 04:17 PM
Yet another very positive K-7 review at Trusted Reviews gazonk Pentax News and Rumors 0 09-03-2009 01:24 PM
DOF preview on K20D ???? trublubiker Pentax DSLR Discussion 2 01-28-2009 07:23 PM
K20D preview now available at DPR WaterDog Pentax News and Rumors 18 06-21-2008 07:36 AM
K20D review (Trusted Reviews UK) Adrian Owerko Pentax DSLR Discussion 6 04-20-2008 06:15 AM



All times are GMT -7. The time now is 08:02 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top