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x Megapixels

I am no expert, when it comes to photography, but I was wondering what the advantage is of having a higher number of mega pixels?

Is it only of good use, if you have one hell of a good printer?

My thinking is this... I have a 3.2 Mega Pixel camera (Fuji S3000) and when I take a photo, usually using 1 Mega pixel setting, it comes out massive on the computer, because of the number of pixels it uses. I then have to reduce it down, to print it on one page.

If I have to do that (Using an Epson CX3200 printer) I presume it's because the printer doesn't print that many pixels.

Therefore, if I were to then take a picture at 3 Mega pixels, I would get a bigger picture, which I would then have to reduce to exactly the same size, to print it.

More than that, I would imagine that reducing from (for example) 3 mega pixels to 0.5 mega pixels would lose more quality than reducing from 1 mega pixels to 0.5 mega pixels.

So, this would mean that the higher the resolution of the original picture, the lesser the quality of the print.

So the question is... For the vast majority of people buying digital cameras, for use on normal computers, with normal printers, are a higher number of pixels just a pretty selling point, with no value to Joe public?

Just a thought. Happy

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Megapixels

In reply to: x Megapixels

The higher the megapixels, the larger the photo can be printed and still maintain photolab quality. Imagine a 20"x30" picture with the same quality as a glossy 5x7.

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Pixels and Dots Per Inch.

In reply to: x Megapixels

Dont think in megapixels - think in terms of image size.

For viewing on a monitor you want a size of:
640 x 480
800 x 600
1024 x 768
because that will fit on most monitors.
(depending upon the screen resolution setting).

For printing you will need larger image sizes:

Most inkjet printers do their best printing at 300 dpi (dots per inch).

Take the 640 x 480 photo and print it a 300 dpi and you will get an excellent print of the size of 2.13 x 1.6 inches. (not very big).

I divided the 640 and 480 by 300 (dpi).

Take the 1024 x 768 photo and you get an excellent print at 3.4 x 2.56 inches (still not very big).

Take a 3 megapixel photo which is 2048 x 1536 image size. Now you will get an excellent print that is 6.8 x 5.12 inches (now we are getting somewhere).

As you can see, it is all mathmatics (no magic).

......................................

It is best to take the photos at 3 megapixels because you can get excellent prints of a nice size.

But when you want to view them on the screen or send them to someone, you should use a software program to resize/resample the large image and create a smaller image.

When I send a group of photos to a friend.
I burn them to a CD
And I have two folders on the CD.
One for viewing and one for printing.

................................

Here is a writeup that gets down to the nitty gritty of the math involved:

http://www.shortcourses.com/pixels/index.htm

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Thanks

In reply to: Pixels and Dots Per Inch.

I do talk some tosh! Happy

That makes pretty good sense. Thanks for that

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Megapixels

In reply to: Pixels and Dots Per Inch.

That was a great explanation. Here is how I remember things:

a 2 megapixel camera will make a good 4x6 print.
a 3 megapixel camera will make a good 5x7 print.
a 4 megapixel camera will make a good 8x10 print.

Also, a good program, if you are looking to just print an image on a single sheet of photo paper, is Irfanview. It is freeware, and a very small program. When you print, you can select your paper type in printer settings, and you can select "stretch to page" which will make the picture just big enough to fit onto the paper. Now you won't have to worry about resizing an image before you print it.

Also, HP printers come with great software for making prints. You just open a picture, select what size prints you want to make, then drag the .jpg (or whatever) to the example place on the page you want it to print. Then hit print, and you're done! Again, no resizing images beforehand.

Hope this helps!
Susan

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Right on, snapshot2 !

In reply to: Pixels and Dots Per Inch.

Joe, I was about to answer in exactly the way you wisely recommended, when I read your post!
As a technician involved in digital and commercial printing (paper&ink magazines), I highly confirm your advice.
And thanks for the "Short Course" link! We owe you one!
Tom

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Hey Snapshot got a ?

In reply to: Pixels and Dots Per Inch.

Snappy, Grin

After reading your post I was hoping you could explain the following... And I quote:

'When I send a group of photos to a friend.
I burn them to a CD. And I have two folders on the CD.
One for viewing and one for printing.'

Can you please tell me how you (place) two folders on a CD or possibly point me in the direction of a tutorial or two on the subject?

Thanks ever so, S
WindowsXP (home ed)

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Folders on CD

In reply to: Hey Snapshot got a ?

There are several ways to put folders on the CD, but the simple method is to make two folders on your hard disk and put the viewing photo files in one and the printing photo files in the other.

Before you write anything to the CD, you have to choose what you are going to write. Instead of choosing to copy the photos, choose to copy the folders.

The exact method of how the choosing is done is dependent upon what software you are using to write the CD.

I use Roxio to burn most of my CDs.
I select "Data" then "Copy files to disc"
I highlight the files and/or folders that I want on the CD and then click the icon (looks like an arrow) that says "Add selected files above to project"

They are copied to the lower window and
then I click the "Burn" icon.

In the next window I check-mark "Read-only disk", then click "Burn"


...
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Megapixels and photo size

In reply to: x Megapixels

When you take a picture at the higher megapixel setting, you're going to get a bigger file and that large picture you see on you screen. As mentioned earlier, using software to re-size the image (still keeping the dpi at 300dpi for printing purposes) will make it easier to view. If you want to email the photo, drop the dpi to 96dpi so that the folks on the other end don't have a huge file attachment.
A good rule of thumb: 3 megapixels will create a very nice quality 5x7 photo; 4mp will create a very nice quality 8x10; 5mp = 10x13. I would only recommend the lowest mp setting for photos for the web and/or email (again, file size is larger and loading/opening the picture is longer the higher the mp are).
As far as printing photos goes, 300dpi is the most common setting that will produce decent results. If it's a photo that you REALLY want to "shine", put your printer settings to 600dpi -- for most folks anything above that is overkill (and you waste a ton of ink!) A little tip: before you bump up that dpi for printing, do all of your "editing" -- photo fixing -- then print in DRAFT MODE if you need to see what it will look like on paper. If you're happy with it, then change your settings. Also choosing the correct PAPER TYPE in the printer options is almost as important since the printer is programmed to recognize different papers and the coatings/qualities of them.
Hope this helps!

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I don't print my own pictures any more.

In reply to: Megapixels and photo size

Rather than resize and resample my picture for printing I send email to my local Wal-Mart photo finishing department in the large megapixel size, tell them what size print I want then pick the picture up the next time I am in the store. This costs me less than if I printed it myself at home and I do not have to worry about any conversion. So far I have been very happy with their service. I suppose that other photo finishing vendors offer the same service.

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Printer settings are not the same as image 'settings'.

In reply to: Megapixels and photo size

For example, the Epson 2200 has three settings; 720dpi, 1440dpi, and 2880dpi. One person I work with has determined that the 1440 setting is the best one to use. He did that based on whether he could see a difference in output between 1440 and 2800. He could see a substantial difference between 720 and 1440. Does that mean the image needs to be 1440 ppi? No, anything above 200 is OK with 300ppi recommended.

Why 200ppi on the image and 1440 dpi on the printer? The printer is trying to simulate a continuous tone image. It needs the much higher dpi settings to do this. Don't confuse pixels in the image with dots on the printer. Print at 300dpi, and you will see a very poor print. Print a 600ppi image versus a 300ppi image, and you will see little difference.

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Megapixel Mania

In reply to: x Megapixels

Up until a little after the year 2000, Megapixels were a measure of the possible quality one could achieve from a digital camera. This is because the majority of the sensors were similar-sized CCD technology and had rudimentary software to control the final output.So we were comparing Apples to Apples"back in the old days".

Today is a completely different story. The Amount of Megapixels means very little in todays digital market as technology advances and software and firmware becomes more important to create that final image.
The Quality of the Megapixels and the supporting hardware and firmware is where the true imaging difference is made.
There are many 5 and 8 Megapixel consumer grade cameras on the market with a price point that matches some of the 6 Megapixel prosumer Digital Single Lens Reflex (DSLR) cameras.
The difference in the Quality of these cameras is instantly seen when you compare the RAW image output.
RAW output is like a "digital negative". The camera does not perform any lossy compression or extensive processing on your image when you shoot in the RAW Mode. I would not purchase a digital camera that did not allow shooting in RAW mode. This allows you to see your image as it was affected strictly by your exposure, lens quality and image capture device (CCD, CMOS or LBCAST sensor).
This mode is usually used by professionals and advanced amateurs that wish to perform there own darkroom-style processing using image manipulation software such as Adobe Photoshop or a myriad of other image suites to bring out all the hidden subtle tones and hues possible with their image sensor.
Most of the 5 and 8 Megapixel sensors are only the size of a fingernail (8.8 x 6.6 mm). These are called 2/3rds sensors.These pixels are extremely small and compact compared to the APS sized sensor (22.7mm x 15.1mm) of a 6 megapixel DSLR.

Now here is where we find the beef in the burger!
We have assumed that more is better for years and the marketing people know this, thus a plethora of big number Megapixel cameras have been released in droves onto the hungry Megapixel market.
The one thing that is rarely mentioned in product brochures for consumer and prosumer grade cameras is DYNAMIC RANGE. This is the key that seperates the consumers from the pros.
Tiny sensors, regardless of megapixel count,can only capture small amounts of light and due to their size generate a good deal of digital noise which is obvious when you view the actual pixels on a large calibrated monitor. Some of this noise is also generated by the quality of the lens. Another factor in Dynamic Range is the Bit Depth of the captured image. Most consumer grade cameras only handle a bit depth of 8. This means that there are (2 to the power of Cool 256 discrete tonal levels provided by each pixel. This isn't bad for standard vacation photos and web shots.
LARGE APS or Full 35mm sensors on the other hand can capture More light in the same exposure as the tiny sensor which also allows more information (data) to be captured giving a "deeper" feel with richer tones, less contrasty hues and accurate colors. Professional DSLRs have a bit depth of at least 12. This means that there are (2 to the power of 12) 4096 discrete tonal levels available for each pixel. This is the basic essence of Dynamic Range. It has always been the key element that has seperated photos made with cheap lenses and inexpensive film from the high quality photos produced with finer lenses and finely tuned professional film, This continues to apply to the digital world. The film is replaced by the sensor, the hardware reading the sensor, the firmware processing the data captured by the sensor and the storage and compression method used to save the image to your storage device.

I use my 4 megapixel Nikon D2H DSLR to make superior headshot portraits with incredible dynamic range in the skin tones and shadow areas that would not be remotely possible with a 5 or 8 megapixel consumer camera or even my 6 megapixel Nikon D70 or D100 DSLRs, when shot under the same controlled studio conditions and using only the Manual settings to make sure that each camera is given the same chance to produce a fine print. My 11x14 prints that I produce with my 4 Megapixel Professional camera easily stand up against any film prints I have shot in tha past with my retired 35 mm cameras.

For the average consumer that is not worried about how to make that $1200.00 24x36 inch wall portrait, 3.2 to 4 megapixels are PLENTY! With a properly exposed image, you can produce a stunning 11x 14. Proper exposure and compression method usually determines how big you can enlarge your print when it comes to the digital world. Dynamic Range determines the WOW factor of your print once it is enlarged and put on display for all to judge.

The best test is to shoot a photo with the camera you think you want and get an 8x10 print out at a one hour digital kiosk. If you say "WOW" when you see the print, you found the right camera.

QUALITY continues to rule over QUANTITY.

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Thank you ! Have a question

In reply to: Megapixel Mania

I am ready to buy a new digital camera - my old Olympus has 1.3 megapixels. Your post here was very helpful. New question: What about optical zoom? A friend said make sure you get at least 8X optical zoom.
I basicaly want 35 mm quality in a digital camera and mostly point and shoot with some features. I photograph (fast moving!) grandkids, scenery, and photos of photos/portraits for family history. Would love to be able to print portrait quality 8 x 10. $500 is my limit including accessories.
Looking at Nikon, Sony, Casio Exilim, Canon maybe - but confused by models. Can you suggest a Nikon model # for me (or any other camera). I'm so confused I can't make a decision. I will be keeping the camera for a very long time - so this is a big decision for me! Thank you in advance...

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I'll see your 4megapixel camera, and raise you an

In reply to: Megapixel Mania

8megapixel Canon 20D or Mark II. I bet I'll get a better image, under the same conditions, than you. While I agree with most of your post, one simply cannot say that megapixels do not matter. If they didn't matter, pros would not be paying megabucks for cameras with very high pixel counts.

I think you need to say that, right now, high pixel counts are expensive. There is no free lunch. In the future, they will not be as expensive.

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Invaluable information

In reply to: Megapixel Mania

This is worth a copy & paste for future reference. Thanks, Doc!

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Framing your subject

In reply to: Megapixel Mania

Megapixels do matter. I wouldn't purchase a camera with less than 3.2 megapixel capacity. However, most of us amateurs don't even exploit the full capability of our equipment.

For example, my camera (Olympus 750 series, 4 MP) allows me to use TIFF; however, this would only let me take 20 photos on my 256 MB card. I dont even use the second quality, SHQ. Instead, I elect to use HQ1, which lets me take about 285 photos before I fill my card. If you do the same, you're kidding yourself about the importance of megapixels.

Instead, consider Zoom; my camera allows 10x zoom, which gives me the opportunity to frame my subject closely (crop in camera). This is at least as important (except for impulse shots (snapshots), where you can make up for lack of planning by using only a tiny portion of your initial capture to make your final image.

As a former (competitive amateur) user of film cameras (Nikon F) I have some experience in making good use of my small negatives to produce large images, and I regard zoom as a more important attribute than huge megapixel capacity for most amateurs.

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The problem, of course, with zoom is that it is best used on

In reply to: Framing your subject

a tripod. If you are shooting hand held, it is tough to hold the camera steady enough for a good shot. Also, high zoom numbers are usually very misleading. They refer to the ratio between the full zoom focal length of the lens, and its maximum wide angle focal length. This number does not tell you very much about the camera's magnification ability, and it should really be the amount of magnification you get that is important. By magnification, I mean the extent to which the camera can 'see' better than your 20-20 vision.

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