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-   -   Nikon D90 or Sony A550?? (

Bruno28 Nov 29, 2009 6:35 AM

Nikon D90 or Sony A550??
I had decided to buy a Nikon D90 a while ago.
Now that i have the sufficient cash, i saw that sony has a new model out.
Now i'm undecided between the Nikon D90 or a Sony A550.
The sony is cheaper and it does look like it has a better performance, but i might be wrong.
Can anyone help me?? any comments or concerns about the two models??
I would primary be taking pictures of nature, landscapes, animals and buildings.
Thanks in advance.

TCav Nov 29, 2009 7:09 AM

The Sony A550 has a 14MP image sensor, while the D90 is only 12MP. The A550 can use higher ISO settings, and has sensor shift image stabilization in the camera body while the D90 relies on certain lenses to stabilize the image. While the D90 has a greater selection of lenses available for it, only about half of them are stabilized. All Sony's lenses are stabilized, as are all third party lenses and all the A-Mount lenses on the used market.

The biggest difference is the image stabilization, which, given what you say you want to shoot, I don't think will make much difference.

So I think it comes down to the details: 14MP image sensor in the A550 v. 12MP in the D90, 12800 maximum ISO v. 6400, tiltable LCD display, but the A550 can't record videos.

Bruno28 Nov 29, 2009 4:19 PM

Thank you TCav
i agree with you. The sony does have a a greater image sensor, but does that really mean that the images will be better quality compared to the nikon sensor?
Image stabilisation the sony wins, since it in body built.
I've seen only one review on the A550, but it said that at iso 12800 the image had lot of noise. Do you think that at iso 6400 both cameras behave the same? or which one is better image quality at those iso?
The sony has a lowest iso of 200 while the D90 has a lower of 100. whould this be something to take in consideration?
Movie is not something that is so important to me. its good to have it in case you need to film something at the last moment, but i already have a HD camcorder.
Price wise, from where i'm from the A550 is $1100 with twin kit lense (18-55mm and 55-200mm) and the D90 is $1300 with 18-105mm. so in prise wise the Sony also wins.
My only concern is if the sony has all the functionality as the nikon and image quality.

TCav Nov 29, 2009 5:58 PM

The A550 is new, so tehre isn't a lot of data onit yet. Comparatively speaking, the D90 has been around for a while and is a known quantity. They are both fine cameras and will do what you want, and do it well. The differences are minor.

Image stabilization is nice, but from what you say you want to shoot, I don't think it would be much use to you.

Go to a store and check them out for yourself. If you can't comforatbly hold the camera, if you can't find the controls and commands when you need them, you'll miss shots and you'll be dissatisfied with it.

JimC Nov 29, 2009 6:01 PM

I've seen comments from a reviewer (at a site specializing in Sony Alpha Mount products) that the A500 has the better image quality between the A500 and A550 after thorough testing of both (and the A500 is less expensive, too). This particular reviewer also decided to buy the A500 for personal use. Of course, that kind of thing is always subjective and I've seen others say they prefer the A550 output.

The A500 is using a new Sony 12MP CMOS Sensor design. Note that the Nikon D90 also uses a Sony 12MP CMOS Sensor. There are going to be some differences in image processing, etc. between them unique to a manufacturer (and there are probably some differences in the sensor, too). But, the output should be similar.

As for the ISO range on the D90, ISO 100 is an "Expanded" Setting (the native base ISO of that sensor is ISO 200). Basically, if you want to use ISO 100, the camera is overexposing the image by a stop, then adjusting the apparent exposure during the in camera processing. You'll lose Dynamic Range (around a stop of highlight range) using it. So, it's best to avoid the ISO 100 setting (since you'll end up degrading image quality if you use it). If you look at the D90 specs, you'll see that it's shown as an expanded setting:

You'll find feature differences between them, but you may not care about them.

I'd try them out in a store to see what you're more comfortable with and compare some of the feature differences (for example, the larger viewfinder of the D90 versus the faster Live View Autofocus of the A500 with it's tilting LCD). The D90 also has Mirror Lockup and DOF preview. But, the Sony has some nifty features like the new Auto HDR. You'll see a good list of the A500 features at

Note that the A500 has a lower resolution LCD compared to the A550 (it's a shame that Sony didn't include it on the A500). But, I'd probably lean towards the A500 anyway if I were picking one of those Sony models. BTW, I recently noticed this listing over at B&H (but, I haven't seen it show up on other sites yet, so they may have posted it earlier than they were supposed to):

Bruno28 Nov 29, 2009 6:50 PM

Thanks TCav
as both cameras have very similar performance and feature that i look for, i am leaning towards the sony, since it has a lower price. With this extra cash i could invest in a lens or something else.

Bruno28 Nov 29, 2009 6:56 PM

Thanks JimC.
I think i would still pick the A550 over the A500, because the A550 has 7 fps, better quality screen and 14 MP.
I will definitely have to go to a store and test both to see which one is best for my fitting, which one has better building quality, weight, grip comfort and so on.

What exactly is Mirror Lockup and DOF preview on the D90? could u please explain, and would i use this often?

TCav Nov 29, 2009 7:23 PM

Keep in mind that, even though the A550 can shoot 7 fps, it won't change focus or exposure from frame to frame. If you are shooting a sequence and your subject moves, it may be out of focus. and if the lighting conditions change (as you pan, for instance) later images might be under- or overexposed.

Mirror Lock Up is a feature that reduces shake when the camera is mounted on a tripod. When a dSLR takes a photo, the mirror raises up out of the way so the image sensor can be exposed. If the camera is on a tripod, the mirror quickly raising can cause the camera to shake, causing motion blur during longer shutter speeds. Mirror Lock Up locks the mirror up for a second or two before taking the photo while the camera stops shaking.

The DOF Preview feature lets you see the depth of field that you'll get before you take the shot. dSLRs keep the lens aperture wide open so there's plenty of light for you to compose the image, adn for autofocus and autoexposure. When the lens is wide open, the depth of field is shallow, meaning that objects in front of and behind the subject will be out of focus. The distance from the subject that objects will be in focus changes with the aperture. The DOF Preview feature closes down the aperture to that which has been selected for the exposure, so that you can see how objects infront of and behind the subjects will be in focus or not.

JimC Nov 29, 2009 7:29 PM

The 7fps mode doesn't Autofocus between frames (after a focus lock, it doesn't adjust it for subsequent frames). You're limited to 5 fps per second (with the Optical Viewfinder) if you want Autofocus tracking of moving subjects (slows down to 4 fps with Live View)

Yes, the higher resolution LCD would be something to consider. I'm currently shooting with a Sony A700, and I like the higher rez LCD for image playback (the A700 doesn't have Live View).

Mirror Lockup is a feature designed to reduce vibration from mirror slap by locking the mirror up (blocking the optical viewfinder) prior to taking a photo. It's used for slower shutter speeds when using a tripod and is mostly useful at longer focal lengths. I haven't used that feature in a long time. DOF (Depth of Field Preview) is designed so that you can press a button and the aperture closes down to the aperture it's going to use for shooting (so that you can better judge Depth of Field). It's a feature that I personally never use.

JimC Nov 29, 2009 7:30 PM

It looks like I took too long typing. TCav beat me to it (I didn't see his post before I finished typing). ;-)

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