Question on mega-pixels

[Terri French]

I just purchased a little point and shoot for my purse. It is 10 MP which is more than I need in this sort of camera. I hear that the sensors don't perform as well when more mega-pixels are crammed onto them.

Here is my question--where will I have the best images. I can shoot this camera at its full 10 mp high. It also has an option for 10 mp normal, or I could go down to 7 mp normal. Does changing the number of mp per shot improve performance on a small sensor when the camera is designed for 10 mp.

Hope this makes sense..... I'm electronically challenged.:biggrin:

 

[Commodorefirst]

Terri, what they do is change the compression on the camera to get a smaller MP file size, On thing it might have is a landscape mode or different crop mode that might suit you better than either the 4:3 ratio or 2:3 ratio the camera may have. This would change the MP amounts.

I keep all of my parents P&S set at JPG large fine, and don't have to many problems.

For around the house shots the normal compression will give you smaller file sizes but if you are outdoors and want a scenic stick with JPG large fine.

you will not change or improve the sensor with changing the MP amount

Cheers,

Wade

 

[Removed User 5]

Here is my question--where will I have the best images. I can shoot this camera at its full 10 mp high. It also has an option for 10 mp normal, or I could go down to 7 mp normal. Does changing the number of mp per shot improve performance on a small sensor when the camera is designed for 10 mp.

Nope. Think of the sensor like a screen door; the square spaces between the screen as the actual sensors. You can't change the size of those squares, and only so much air is going to go through any individual square.

Now, if you could go from 10MP down to 2.5 MP, then the camera could average 4 "real" pixels for every pixel output (i.e. a 2x2 average), and possibly get a better picture that way at the expense (obviously!) of resolution. But I'm not aware of any P&S that has that option.

Set it to 10mp high and you'll get "the most" out of that camera that it can produce.

 

[Tom Swaman]

Terri,

Your best bet is to keep your ISO at the camera minimum setting and shoot in JPEG, Large, Fine mode or JPEG Optimize Quality mode.

Regards,
Tom

 

[Muonic]

Hi Terri,

I've been looking into P&S cameras lately, and it seems the manufacturers want to cram as many mega-pixels as they can into a camera now, as a marketing ploy. They figure the average person will think that more is better, and thus the logic. And while these cameras work reasonably well at a low ISO setting, they suffer at high ISOs, because of the high mega-pixel count on such a small sensor. So as others have said, try to keep the ISO as low as possible, and it should work fairly well for you.

I hear that the sensors don't perform as well when more mega-pixels are crammed onto them.

 

[turtile]

Like already mentioned, the sensors remain the same size no matter what you do.

No matter what setting your camera is on, it will take the photo @ 10MP and resize it to the selected size. So if your camera is set @ 7MP, your camera will take the picture @ 10MP, resize it, and store the resized version on the memory card.

Unless you want to save space, there is no point of using a lower resolution.

 

[Lurker]

There is no doubt that the camera takes the picture at the original resolution and then resizes it. But I do not agree with "there is no point of using a lower resolution" - averaging pixels is a great way to combat noise, and that is exactly what happens when you downsize an image!
Given that noise is the big problem on P&S cameras (especially at any ISO's above 25 it seems), saving at a lower resolution could make sense in that respect - if you find a lack of noise more important than an unnoticeable increase in resolution.

 

[Desmond]

What camera is it ? The Panasonics seem to average out pixels for noise reduction .
My Fuji F31 does good iso 800 but I have found that shooting wide angle at F2.8 and cropping gives better results than zooming in and dropping to F5 along with the reslulting increase in iso .

 

[Terri French]

I am getting a great education here. The camera I bought is the new Nikon s600. I'll have to experiement with it to see if I can tell if there is a drop in noise in resizing smaller. So far it seems that noise isn't a huge issue with the camera.

Thank you very much for the time that you all spent helping me understand my new camera better.

 

[LDB415]

Confirming what I believe I read and what I thought as well, by choosing the 7mp or 5mp or whichever lower setting you are only reducing the space requirement and thereby being able to store more shots on any given memory card?

 

[Tom Swaman]

Terri,

Here is a novel thought. Have you considered sending an e-mail to Nikon Technical Support or calling their North American phone line and posing your question to them? When I have done this, I have received between a 70% and about an 85% satisfactory response in a short time period.

Just a thought.

Tom

 

[Terri French]

Terri,

Here is a novel thought. Have you considered sending an e-mail to Nikon Technical Support or calling their North American phone line and posing your question to them? When I have done this, I have received between a 70% and about an 85% satisfactory response in a short time period.

Just a thought.

Tom

Good suggestion. Thanks.

 

[Philippe Roger]

Hi Terri,

you can verify the "resizing down leads to less noise" theory yourself, by taking a 10MP image and resizing it down to 2.5MP (i.e. a 50% resize in each dimension, height and width), using Photoshop or your favorite image processing program. Add a small amount of sharpening, (say amount=200%, radius=0.3, threshold=0) after the resizing step, or use PS's bicubic sharper algorithm for the resize operation, and now compare the images at 100% on screen. The smaller one will have tremendously less noise. :wink:

 

[Desmond]

On dpreview there isn't a full review on that camera but there is one on another of their 10 meg compacts , possibly not the exact same sensor http://www.dpreview.com/reviews/NikonP5000/page13.asp .
They mention pixel-binning at iso 3200 only . There are some more comparisons at different iso levels there too . With a range of F2.8-5.8 I would definitely advise shooting at 28mm f2.8 and cropping rather than 112mm f5.8 in low light situations since you will get a cleaner image at iso 100 cropped compared to iso 400-800 zoomed in .