Resolution, Sensitivity and Image Quality

Sony likely wanted to scoop the industry with the 14.2MP resolution of the entry A350. That plan probably got scrapped by the 14.6MP Samsung CMOS sensor used in the prosumer Pentax K20D. While the A350 doesn't gain bragging rights as the highest res sensor south of $8000 it is still mighty close at 14.2MP. It is also the highest resolution sensor to be found in any current or announced entry-level DSLR.

Pentax went to great lengths to emphasize the greater size of their photoreceptor sites that made sensitivity more akin to the Sony/Nikon 12MP sensor. Pentax also emphasized the expanded sensitivity of their 14.6MP sensor with ISO options to 6400. Sony makes no special claims for the 14.2MP sensor in the A350, but the new sensor still has the option of ISOs to 3200.

We've already discussed how the A350 is easy to use with the best Live View you can find in a DSLR these days. The big remaining question, then, is whether the 14.2MP sensor really makes any difference in image quality.


To answer that question we considered that the most revealing test of sensitivity, noise, and resolution is low tungsten light typical of home interiors. The selected scene was not chosen to be pretty but to be revealing of sensitivity, noise, and image quality. It is a shot of my office stacked with motherboards and other review equipment taken with a standard 50mm f1.4 lens.


We found the APS-C 14.6MP CMOS sensor in the Pentax K20D to be excellent in sensitivity with well-controlled noise. The sensor size and resolution is roughly comparable to the A350, but the camera is much more expensive, uses a CMOS sensor rather than CCD, and it is targeted at the prosumer rather than entry-level. For those reasons, we included the Pentax K20D in these comparison tests.


The Canon 5D is justifiably famous for its incredible resolution with the full-frame 12.2MP CMOS sensor. The larger size sensor creates larger photo sites and the larger pixels are more sensitive to light than smaller APS-C sensors. The larger sensor size means the pixel size is more like an 8MP APS-C than a 12.2MP sensor. That makes for a good comparison to these two 14+MP sensors.

All images used a 50mm f1.4 lens (Pentax 50mm f1.4, Sony/Minolta 50mm f1.4, Canon Ultrasonic 50mm f1.4). Aperture Priority was used with a fixed aperture of f4 at all ISOs on all three cameras.  Shots were taken using a tripod and remote shutter release to prevent shake. High ISO Noise Reduction used the lowest level of high ISO NR that could be selected in each camera. White Balance was manually set to Tungsten on each camera and the only light source is a 100W tungsten bulb. These harsh test conditions should make image noise as severe as you will likely see in each camera short of time-exposure darkness. Images were captured in JPEG format so they could be displayed and downloaded without the requirement for post-processing software.

Live View and the Optical Viewfinder Sony A350 vs. Pentax K20D
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  • Wesley Fink - Friday, April 4, 2008 - link

    I have been a Senior Editor at AnandTech for over five years. In fact I have been here longer than anyone except our CEO, Anand Shimpi. I have started or expanded many review areas for AnandTech, brought on-board other AT Editors you will recognize, and handed off new sections to others after getting them up and going. I am NOT quaking in my boots at your threats.

    What I cannot figure out is why you are so determined to discredit me and my work. It certainly won't work, but I cannot figure out your motivation. I can only assume you must be from a photography web site as we have been attacked before by other web sites who were threatened by the success of AT in other areas. If my work is so mediocre and laughable who bother worrying about my camera reviews enough to threaten me? Something is not right with your vehemence and threats.
  • Deadtrees - Saturday, April 5, 2008 - link

    What are you talking about? The question was about your being "PRO" photographer, not about your resume on Anandtech.

    Are you implying that your reviews are bound to be decent because you've been here for some years, did this and that for Anandtech?

    Who cares expect you and your ego? Reader don't care whether you're the founder of Anandtech or the creator of Internet when your camera reviews show too many problems.

    The very methods you've choson only shows how you're incapable of doing the review on this matter and you know it. Stop the ego trip and find someone who can do the review. If you feel like it's something you gotta do as you're the "PRO" photographer, stop doing silly and nonsense benchmarks as you just can't cut it right.

    You see, you're walking down path of Ken Rockwell with this stupid review and ego trip. If you want to do a good review that's not based on benchmarking, www.luminous-landscape.com would be your guide line. Learn from that site instead of Ken Rockwell's.

  • GTVic - Saturday, April 5, 2008 - link

    Wow, you should really calm down before you give yourself a heart attack. The same goes for some of the other people posting here. The tone of your comments is extremely angry and your attacks are largely demeaning (eg. "this stupid review") rather than constructive and friendly.

    Your spelling and grammar are so atrocious and juvenile that I imagine you are writing these comments with steam coming out of your ears due to your intense anger. In short, you have very little credibility in spite of all the technical details that you so venomously spew out.
  • brian_riendeau - Saturday, April 5, 2008 - link

    I think the motivation for a lot of people is the fact that they like AT (otherwise why would they be here reading your article?) and this feels like a letdown. I posted some stuff earlier that may not have been in the best tone, however I can assure when I first clicked on the article I was really excited to read it. Then when I finished I was like "Wow.........." A lot of computer enthusiasts are photogs as well, and its frustrating to come to a site we look to for solid information and read this article. Personally I am someone who currently knows more about cameras than PCs, so reading a head scratcher like this article can make me question some of the PC hardware articles and discredit those.

    Its also frustrating that you do not have the camera anymore. DSLRs can be finicky things and often the best results or feedback comes from second and third looks at the camera. Obviously you are trying to generate some traffic and expand the site user base a bit. Now what I would love to see if for AT to take the feedback from this, and consider that for a revision to this article or at least future articles. I would love to see a good comparison over the current crop of <$1K DSLRs.

    Just keep in mind that megapixels really do not matter. Photography is extremely subjective, and when it comes down to it, people want to know what will take the best pictures for them.
  • kleang - Friday, April 4, 2008 - link

    Well done on the review and all correction you're doing. This type of review is really what's I'm seeking for.

    Who's care on everything must be perfect or measured right? I just need something easy to understand, some opinion from pro, some compare to guide what's I got if I buy this product.

    If I seriously to buy and need in depth information, dpreview and other many sites is my choice.

    May be I'm just your target group, and I'm sure this group is large segment from now.
  • punchkin - Friday, April 4, 2008 - link

    This is not an opinion from a pro. In addition, if you actually don't care about basing your opinion on wrong information, you can satisfy yourself easily with a random search anywhere on the web. Hell, I'll send you bad advice for free if you give me your email address.
  • kleang - Saturday, April 5, 2008 - link

    1. You need to build your credibility 1st if you want to give any advice to people. At the moment, your credit is zero for me(sorry to say that).

    2. Anandtech is one of best information web for a long time, so any advise is good to hear. And I think they response to many comment as a pro, try to correct and very patient to answer.

    3. Many comment are very good and helpful but some just try to blame and show off.

    4. Like it or haste it, just give polite comment and it's depend on AT if they think it's neccesary or not to correct. No meaning to try to blame to prove you're right. AT must responsible on their review but we (you and me) just reader which didnt provide even realname/email.

    5. It's helpful to point the error and give some opinion. But let reader decided if they think this review is helpful or not, you may just not the target group.

    Just my 2cent.
  • punchkin - Saturday, April 5, 2008 - link

    1. We're not discussing your belief in my credibility, but the credibility of the reviewer and his "review".

    2. Nope, obviously NOT for camera information. The word is "advice". Bad advice or "advise" is bad to hear.

    3. My comment is dead on point. A "review" that puts vastly different lenses on different camera bodies, and "tests" using wide-open apertures to show supposed merits of the sensor in each camera, or the imaging capabilities of each camera system, is UTTERLY WORTHLESS.

    4. Like it or not, your half-intelligible posts here do nothing to show that the review has any worth whatsoever. If you want to play "politeness police", go elsewhere.
  • kleang - Saturday, April 5, 2008 - link

    "4. Like it or not, your half-intelligible posts here do nothing to show that the review has any worth whatsoever. If you want to play "politeness police", go elsewhere. "

    Just in case you didn't realize, this post already shown yourself to the public, lol.
  • punchkin - Saturday, April 5, 2008 - link

    Let's try to keep this to standard English. :D

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