PentaxForums.com

Go Back PentaxForums.com > Pentax Cameras > Pentax DSLR Discussion > K20d Problem

Pentax DSLR Discussion Talk about Pentax Digital SLR modes, technique, operation, and problems here (K and *ist D series).

Reply
 
Thread Tools Search this Thread Display Modes
10-13-2009, 03:07 PM   #1
Site Supporter
 
Location: Florida Gulf
Gallery Photos: 5
Posts: 1,597
K20d Problem

I took both photo's with the same settings with my K20d and K100d and Sigma 100-300 on a tripod the exact same distance. So what is wrong with my K20d? The K100 takes a much clearer photo.
Click to enlarge to see the 1600x1200 shots.

K20d

K100d


Thanks Guys & Gals
Fl_Gulfer is online now  
10-13-2009, 04:14 PM   #2
Site Supporter
 
Location: virginia beach, VA USA
Gallery Photos: 6
Posts: 735
You seem to be an experienced photog so I don't know why you post two shots with no information about the camera settings and want us to guess at what is different. At least we can see the ISO, f-number and exposure time are a little different between the two. The color difference may be due to the K100 using sRGB for its color space while the K20D has an "unregistered" color space that obviously is not a camera setting, maybe changed in PP. A hundred other menu settings affect the picture. What exactly are we looking for?
imtheguy is offline  
10-13-2009, 04:27 PM   #3
Site Supporter
 
Location: Boston, US & Bucharest, Romania
Gallery Photos: 0
Posts: 395
The K20D pic seems underexposed.
causey is online now  
10-13-2009, 04:30 PM   #4
Ash
Site Supporter
 
Location: Toowoomba, Australia
Gallery Photos: 100
Posts: 7,982
By same settings do you mean same Tv, Av and ISO in M mode for both cameras?
Or do you mean same camera mode but auto metering?
More info required for sure.
Ash is online now  
10-13-2009, 04:49 PM   #5
Pentaxian
 
Location: Wisconsin USA
Gallery Photos: 2
Posts: 1,635
Originally Posted by Fl_Gulfer View Post
I took both photo's with the same settings with my K20d and K100d and Sigma 100-300 on a tripod the exact same distance. So what is wrong with my K20d? The K100 takes a much clearer photo.
Click to enlarge to see the 1600x1200 shots.

K20d

K100d


Thanks Guys & Gals
Besides the WB and exposure differences??... Anyways it seems the k20 front focused a bit. Aperature looks fairly large (by my guessitmate) and DOF is not very deep...
jeffkrol is offline  
10-13-2009, 05:00 PM   #6
Site Supporter
 
Location: Florida Gulf
Gallery Photos: 5
Posts: 1,597
Sorry they were both set on the green setting, ISO is on Auto. I set everything so the camera would make the best settings on both. I was mainlt wondering about the poor focus of the K20d, I always wondered why the K100d took much better shots.
Fl_Gulfer is online now  
10-13-2009, 06:09 PM   #7
Moderator
 
Location: Denver, CO
Gallery Photos: 15
Posts: 4,698
Originally Posted by Fl_Gulfer View Post
Sorry they were both set on the green setting, ISO is on Auto. I set everything so the camera would make the best settings on both.
"Best" settings in theory for some purpose, maybe, but th camera can't read you mind as to your intent, and the settings chosen by the K20D were not ideal for your particular particular purpose here. According to the EXIF, the K20D chose ISO 100 and f/4, yielding a shutter speed of 1/350", which would have been great *if* you had managed to hold steadier than you did, and if you didn't mind the shallow DOF that resulted from shooting 300mm at f/4. The K100D doesn't have the option of ISO 100, so it went to ISO 200, whicvh gave you a faster shutter speed, which enabled you to get a less blurry photo. Also for whatever reason chose f/4.5, which yielded slightly more DOF - probably just enough to create the illusion of a sharper photo. Then, on top of that, the K20D happened to choose to focus on a part of the dummy that was a little forward of the part of the dummy the K100D chose to focus on.

I always wondered why the K100d took much better shots.
Uless your particular K20D is defective - and nothing about this test suggests it is - then it should be capable of doing as well as or better than the K100D. You can't base too much on one test like this where you failed to control any of the basic parameters that contribute to the things you are testing for.
Marc Sabatella is offline  
10-13-2009, 06:40 PM   #8
Pentaxian
 
Location: Singapore
Gallery Photos: 32
Posts: 2,103
Exposure and ISO not to mention auto settings between the two images are different. So naturally the images will look different.

K100D: 1/500sec at f/4.5 ISO 200 Portrait mode
K20D 1/350 sec at f/4 ISO 100 Program (Auto)

Last edited by creampuff; 10-13-2009 at 06:47 PM.
creampuff is online now  
10-13-2009, 06:51 PM   #9
Member
 
Location: Boston, MA
Gallery Photos: 1
Posts: 76
there is exif info on those images.
go to online exif viewer like:

Jeffrey's Exif viewer

and put in the url of the image.
K20D Image
sharathk is offline  
10-13-2009, 08:11 PM   #10
Ash
Site Supporter
 
Location: Toowoomba, Australia
Gallery Photos: 100
Posts: 7,982
Then the results are just not comparable.
Green mode takes over far too many variables - or perhaps the comparison is between two green modes from two different cameras...

Either way, there's no 'problem' with the K20D from what we see here.
Ash is online now  
10-13-2009, 08:17 PM   #11
Site Supporter
 
Location: Florida Gulf
Gallery Photos: 5
Posts: 1,597
These photo's were taken on a tripod with a wired remote switch. I unscrewed the camera from the lens while on the tripod as to not move anything.
I know the lighting is different but the focus should have been the same on both shots. The k20 is no where close to as good as the K100.
All this time I thought it was my wife having a steadier hand, but now that I spent all this money on a great tripod I see its the camera thats screwed up.
Fl_Gulfer is online now  
10-13-2009, 08:21 PM   #12
Moderator
 
Location: Denver, CO
Gallery Photos: 15
Posts: 4,698
I still don't see evidence of that. Like I said, the cameras appear to have happened to have chosen two different areas of the image to focus on, and the K20D was saddled with a wider aperture - meaning less DOF, and also a simply less sharp image. As for the tripod, I take it then you used the two-second timer?

There's still just far too many vairbales to conclude anything meaningful from this test. Shoot a series of images while controlling the focus better and using the *same* exposure before leaping to conclusions.
Marc Sabatella is offline  
10-13-2009, 08:22 PM   #13
Pentaxian
 
Location: Houston TX
Gallery Photos: 4
Posts: 1,507
I agree it's hard to draw conclusions from these two shots. However, I'd consider taking some more shots with the lens/K20D combination to see if others are slightly OOF. If so, you should try the in-camera adjustment. I was always a little dissappointed in my Bigma shots, but I adjusted the focus in my K20D and now the shots are just a little sharper, and that makes all the difference.

BTW, on the K20D shot, did you wait for the SR to engage before snapping the shutter? It looks like you could have a slight bit of camera shake.
rfortson is offline  
10-13-2009, 08:28 PM   #14
Site Supporter
 
Location: Florida Gulf
Gallery Photos: 5
Posts: 1,597
I'll take some more shots tomorrow after class to show you what I mean. I'll make sure everything is the same.
Fl_Gulfer is online now  
10-13-2009, 10:56 PM   #15
Site Supporter
 
Location: virginia beach, VA USA
Gallery Photos: 6
Posts: 735
Originally Posted by rfortson View Post
BTW, on the K20D shot, did you wait for the SR to engage before snapping the shutter? It looks like you could have a slight bit of camera shake.

It better not have engaged on a tripod mounted, remote fired shot.
imtheguy is offline  
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes


All times are GMT -7. The time now is 09:18 PM.