Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
06-19-2008, 06:56 AM   #31
Banned




Join Date: Oct 2007
Location: Savannah, U.S./Baguio City, P.H.
Posts: 5,979
of course the D3 is going to be better its FF, less MP's on a larger sensor... but the K20D is the best of the best for what it is.

06-19-2008, 10:43 AM   #32
Pentaxian
falconeye's Avatar

Join Date: Jan 2008
Location: Munich, Alps, Germany
Photos: Gallery
Posts: 6,862
QuoteOriginally posted by séamuis Quote
of course the D3 is going to be better its FF
Yes!, but...

FF only means twice as much light, D3@6400 and K20D@3200 should thus be equal. They aren't. A K20D pixel is just 25 sq.micron. A D3 pixel is 70 sq.micron. If we assume a certain overhead of lost aperture per pixel, like 10 sq.micron for borders and electronic components, we actually get a factor of 4 (15 vs. 60). Which is about the story told by the images. Maybe, a price to pay for highest resolution. Because I am really into ISO100 resolution, I am quite willing to pay that price, actually
06-19-2008, 01:44 PM   #33
Forum Member
Ballyclogh's Avatar

Join Date: May 2008
Location: Worcester, MA
Photos: Gallery
Posts: 71
Look...for 99% or photographic needs (pro, semi-pro, or novice...artist, journalist, or dabbler) a K20D is a phenomenal camera at an amazing price. No need to spend an extra $3000 on a Camera unless you REALLY, REALLY need that slight extra boost in quality and capability.

For the Price and for the quality it has, the K20D held it's own against the 16 ton D3 with gusto...
06-19-2008, 05:59 PM   #34
Veteran Member
morfic's Avatar

Join Date: Feb 2008
Location: San Antonio, TX
Photos: Gallery
Posts: 428
QuoteOriginally posted by ukbluetooth Quote
So true - just about every Nikon blows Pentax out of the window when it comes to high ISO. The D3 is just an amazing camera - and yes - I would like one please.

Sorry guys but you get what you pay for.
<canonuser>Haha, funny</canonuser>

06-19-2008, 09:14 PM   #35
Senior Member
Peacekeeper's Avatar

Join Date: Jul 2007
Location: Back at work :(
Photos: Gallery
Posts: 169
I agree

You get what you pay for

Porsche versus Ford

But just driving around town I don't NEED a Porsche

The average Joe needs a reliable capable vehicle that can go from A to B and do all the other things ecpected of a relaible vehicle and in that area ALL Modern DLSRs are capable.

Though if someone offered you a Porsche I doubt you would knock it back and if you could afford one you would prpbably have one...I would...you get to pick up chicks....and compensate for a small......um....er.....lens?

hahahaha
06-19-2008, 09:31 PM   #36
Veteran Member
WMBP's Avatar

Join Date: Dec 2006
Location: Dallas, Texas
Photos: Gallery
Posts: 2,496
QuoteOriginally posted by Peacekeeper Quote
The average Joe needs a reliable capable vehicle that can go from A to B and do all the other things ecpected of a relaible vehicle and in that area ALL Modern DLSRs are capable.

Where this leads - if you're honest - is to the fact that most of the folks who buy dslrs - certainly most of the amateurs - DO NOT NEEED the camera that they're buying and, more than that, might actually be happier with a high-end fixed-lens camera. A dslr makes a lot of things much harder than they would be with a superzoom like a Canon PowerShot S5 IS. Those cameras are much more versatile, if you don't demand total control, and if you don't need shallow depth of field all the time, then these fixed-lens cameras can take really good pictures. The lenses in the better cameras are excellent. The biggest problem with the smaller fixed-lens cameras, aside from the fact that it's difficult to get shallow depth of field with them, is noise. But otherwise, some of them are terrific photo-taking tools.

I don't complain that folks buy dslrs when they don't need 'em because it keeps the price down.

Will
06-20-2008, 12:31 PM   #37
Veteran Member
rfortson's Avatar

Join Date: Sep 2006
Location: Houston TX
Photos: Gallery
Posts: 2,129
QuoteOriginally posted by Ed in GA Quote
Both at ISO 6400

both in Aperature Priority

Mine f/2.8 1/275

His f/2.8 1/300
That's a great story, Ed! I still want to go out and take a motorcycle race shot at ISO6400 1/4000s, f/2.8 and see how it matches up. I'm sure the D3 will be better, and I'm equally sure it won't be $3500 better.
06-20-2008, 12:38 PM   #38
Veteran Member
rfortson's Avatar

Join Date: Sep 2006
Location: Houston TX
Photos: Gallery
Posts: 2,129
QuoteOriginally posted by WMBP Quote
<snip>
It's been my experience that noise is not a simple inevitable and consistent result of a given iso, but rather, it's a result of some combination of iso and settings and available light that I've never been quite able to turn into a calculation.
<snip>
Hi Will,

I've found the same thing. However, I like the fact that at least some of the time, I can take high ISO shots without worry and take advantage of the extra stop or two of exposure and use it for aperature or shutter speed. That's worth a lot to me.

My rodeo shot was taken at ISO 2000, but with a flash (still, it was ISO 2000, f/2.8, 1/180 so it was still pretty dim). There is essentially no noise in that shot, from my perspective. However, I was shooting a friend's band last weekend and didn't want to use the flash. I was shooting at ISO2500 to ISO3200 and the shots were noisy, but still usable. So yes, there is some (to me) indecipherable calculus of situations where the noise is low and ISO is high, but even the "noisy" shots with the K20D don't bother me the way my previous cameras did.

I also imagine the D3 takes advantage of that calculus somehow.

Anyway, you raised a good point and I wanted to say that I've noticed it too.

06-20-2008, 08:36 PM   #39
Veteran Member
Jewelltrail's Avatar

Join Date: May 2008
Location: Rhode Island
Photos: Albums
Posts: 4,180
Has anyone here looked at the D300 @ ISO 6400?


Imaging Resource "Comparometer" ™ Digital Camera Image Comparison Page



Regards,


Ernest

Last edited by Jewelltrail; 06-20-2008 at 09:01 PM.
06-21-2008, 09:54 AM   #40
Veteran Member
WMBP's Avatar

Join Date: Dec 2006
Location: Dallas, Texas
Photos: Gallery
Posts: 2,496
more test images

I've taken a few more test shots with the K20D using high ISO settings. Results can be viewed here:

Picasa Web Albums - William - 20080621 iso ...

Note that I am seldom interested in looking at these images under a microscope. An unprocessed raw image isn't yet a photo, really. I have however uploaded the largest size files Picasa will permit so you can use the zoom button to zoom in and emphasize the noise; and for the fireplace shots, I've provided tigher crops as well, for comparison. I say "emphasize the noise" rather than "see the noise more clearly," because I think "emphasize" is more correct. If you look at a bride's face from five feet away and she looks lovely, looking at her face with a 300mm macro lens isn't "looking at her blemishes more clearly," it's emphasizing something, making it more evident than it really is in normal life and more than you would want. If you shoot a fat person with a wide angle up close, you're not "seeing their width more clearly," you're emphasizing it. What matters to me about photos is whether they will print okay (or view well on screen at normal res), in other words, I'm interested in usable output. And usable output is output that answers satisfactorily to what I saw with my own eyes. If a problem isn't visible until you blow it up really big, then in my book anyway, it's not a problem. I think 100% crops of unprocessed photos tend to be not just unfair, but kind of pointless.

What I find most interesting about these test results is the fairly striking difference in usability between the ISO 6400 shots of the flower and the fireplace, respectively. The flower shows a lot of noise, the noise in the fireplace shot, on the other hand, is much less obvious to me. This is in line with something I've been observing for years, that it's not a simple matter of ISO X (pick a high number, 800 or higher) being absolutely and consistently noisy. Perhaps that's the case at the pixel-peeping level. But at the level of the final shot, I've taken shots at ISO 1600 that were strikingly free of noise, even with the K10D, and at other times, I've taken shots at say ISO 800 where the noise was pretty evident. I suspect that shutter time is a factor, and I also think it has something to do with focus - depth of field, focal plane, something like that although I can't put my finger on it. I am also pretty sure that having more pixels to work with in post-processing makes a difference.

My impression - from what I've seen elsewhere - is that just in terms of noise visible in the final output, at ISO 1600 and above, Pentax K20D competes pretty well with the other cameras in its weight class, like the Sony A700, the Nikon D300, or the Canon 40D.

Will
06-21-2008, 10:59 AM   #41
Veteran Member
WMBP's Avatar

Join Date: Dec 2006
Location: Dallas, Texas
Photos: Gallery
Posts: 2,496
QuoteOriginally posted by rfortson Quote
Hi Will,

I've found the same thing. ...

... there is some (to me) indecipherable calculus of situations where the noise is low and ISO is high, but even the "noisy" shots with the K20D don't bother me the way my previous cameras did.

I also imagine the D3 takes advantage of that calculus somehow.
Russ,

Striking example in the gallery of test shots I just posted.

This fact - I consider it an empirically established fact - means, I think, that comparison testing can be very tricky indeed. I suspect that practically every aspect of a photo is a factor in the noisiness of the resulting image: not just the camera's sensor size itself (after all, the photos in my test gallery were all taken with my K20D) but also the distance from the subject, the depth of field, shutter speed, colors and textures in the image, and more. For these reasons, comparing, say, an *ist DS at 3200 to the K20D at ISO 3200 isn't easy. That's why I really focus on the end result and whether it's a usable image, rather than trying to compare pixels on screen. It's possible that, at the pixel level, the K20D is noisier than the K10D. I think that's what POP Photo's controversial review said. (Think it was POP Photo.) But who cares? I can say with confidence based on experience that, at the level of final output, the K20D produces better, less noisy images than the K10D. And that's what matters.

This might also explain the OP's comparison of a shot taken with a K20D to a shot taken with a Nikon D3. There's a difference between being a millionaire and being a billionaire. But the millionaire and the billionaire both have much more money than needed to buy a nice lunch. In the same way, while the Nikon D3 might truly produce MUCH less noisy images than the K20D, when compared say at 100%, when you compare usable output, the K20D might scale down to normal display size on screen well enough that the noise gets squeezed out. You might have to print images out at 8x10 in for comparison (or larger) before noticing the decisive advantage of the D3. OR, you might have to turn the lights way down while shooting to discover that the D3 can actually GET the shot while the K20D really can't.

In short, I return to one of my basic points, which is that the differences between camera models become truly apparent only in marginal situations. In good, normal light, with a normal subject (say, a cute kid sitting 10 ft away from the camera), almost any dslr on the market today can produce a very good photo. It's only when you get into really interesting challenges that the cameras start to distinguish themselves.

Will
06-21-2008, 12:00 PM   #42
Veteran Member




Join Date: Sep 2006
Location: Bangor, Maine
Photos: Gallery
Posts: 1,382
QuoteOriginally posted by WMBP Quote
I've taken a few more test shots with the K20D using high ISO settings. Results can be viewed here:

Picasa Web Albums - William - 20080621 iso ...

My impression - from what I've seen elsewhere - is that just in terms of noise visible in the final output, at ISO 1600 and above, Pentax K20D competes pretty well with the other cameras in its weight class, like the Sony A700, the Nikon D300, or the Canon 40D.

Will
Will,
I couldn't agree with you more. Shutter speed and amount of exposure are absolute influences on the apparent noise in any image. I've gotten some great shots with my K10D at ISO 1600 if I nail the exposure and shutter speed. The window for error is much smaller with the K10D at ISO 1600 than any of the cameras you mention.

I find the same thing with my A700 when shooting at ISO 3200. It has about the same noise as my K10D at 1600 and the margin for error is equally narrow. Get the settings right and you would swear it's equal to a D3. Be off a little and you are ready to trade it for a P & S.

This next point is beyond my level of understanding. Some images seem to take care of noise better than others. I'm not talking about shadows and dark areas, just general appearance. I can't explain it but some shots seem to not exhibit noise in general for whatever reason.

My conclusion is that the K20D, A 700, 40D, E-3, and D300 are so close on the way they handle noise it comes down to the nut behind the camera.

Ken
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!
camera, d3, dslr, f/2.8, k20d, nikon, office, photography, shot, shots
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Unscientific K-7 ISO testing pcarfan Pentax DSLR Discussion 66 01-14-2010 11:43 AM
Unscientific Kx ISO testing Mr.Turnip Pentax DSLR Discussion 26 01-13-2010 02:31 PM
my unscientific lazy man's ltd lens test nostatic Pentax SLR Lens Discussion 4 12-30-2008 07:35 PM
Unscientific test of firmware versus autofocus Rick Pentax DSLR Discussion 17 05-13-2007 11:41 PM
The big unscientific RAW Converter Comparison HogRider Photographic Technique 0 02-21-2007 11:27 AM



All times are GMT -7. The time now is 11:54 PM. | See also: NikonForums.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