Digicam Translation Question

Can somebody please tell me what the difference is between Standard, Fine, and Superfine image resolution?

I am about to buy a digital camera and I am stuck in a 3 megapixel vs. 4 megapixel debate.

When you select resolution are you actually reducing the number of effective pixels?
In other words, if you buy a 4 megapixel camera and take pictures using Fine resolution are you actually getting the same shot as if you used a 3 megapixel camera and shot it using Superfine?

Can I save $100US by buying a 3 MP and keeping it set to Superfine?---Marc

I cant give specific #s but a standard is 1600 pxls, fine is 2400 pxls and superfine is 3200 pxls. the more pixels in the image the better the resolution BUT the more pixels = more memory is needed for each shot at that resolution. The best resolution images take three times the memory of the same images taken at standard resolution=less pxls per inch.Just consider each pixel as one byte of memory, I know its not correct but the easiest way to visualize it.I have a link to a very detailed digital imaging teutorial if you really want to learn dang near all you could ever need to know about digital cameras and imaging.

Buy a 3MP. 4MP is only marginally better.

The difference between Standard, Fine and Superfine is how much the images are compressed. Superfine is what you should keep it at, because images can be compressed but you can't get back quality lost by compression.

No, you won't get the same shot with a 4MP in fine as a 3MP in Superfine.

The number of pixels in a stored image does change depending on your selection.

By convention for digital images "resolution" refers to number of pixels rather than severity of compression. Some manufacturers are, uh, a bit sloppy in their use of terms. /ubbthreads/images/graemlins/smile.gif

Generally, the best setting (whatever the manufacturer calls it) is the max the camera can do (for my three+ year old Fuji 4700 camera that is 2400x1800 pixels) the other "resolutions" are steps down from that (again on my camera, 1280x960 and 640x480).

That's roughly equivalent to 4.3M pixels, 1.2M pixels and 0.3M pixels per image.

With my usual 128M storage cards that's anywhere from 30 images to 430 images per card.

Some cameras also allow for different compression rates (usually JPEG or LZW compression), and even for storing uncompressed (RAW) images. My next camera will be one that can handle at least 6M RAW and not process the image before storing (no compression).

I do all my shooting at max resolution because one's image can never be better than the resolution of the original, no matter what you do to it. Taking a pic at 640x480 and getting a good 8X10 inch print from it DOES NOT HAPPEN.

Any cropping one does also reduces the effective resolution of a printed image.

At full resolution I can print excellent 5X7's good 8X10's, reasonable 11X14's, and acceptable 24X32 posters.

At minimum resolution a 4X6 print is pushing it ...

You ALWAYS want the image size at the biggest there is.
Make the number of pixels (fine, super fine, etc) to make the image a smaller file size.

Although, I suggest keeping that setting rather high also, and using a photo program to compress the file size.
DONT reSIZE an image to its small on the screen to get a smaller file size. Thats that compression is for.

Try to get ACDSEE. Its a photo viewer, that can resize, brighten, darken, all that,, and has EXCELLENT compression.
Im talking taking a 1 MEG pic, and compressing it to 150 KB, and NOT being able to tell the difference.

www.irfanview.com is also a good image resizer and viewer. Also does batch processing.

[ QUOTE ]
Tomas said:
The number of pixels in a stored image does change depending on your selection.

By convention for digital images "resolution" refers to number of pixels rather than severity of compression. Some manufacturers are, uh, a bit sloppy in their use of terms. /ubbthreads/images/graemlins/smile.gif


[/ QUOTE ]

And how! My new Canon A80 has "normal", "fine", "superfine" settings too. But the image size is the same. It refers to the amount of JPEG compression.

The image size can be changed to 2272x1704, 1600x1200, 1024x768, and 640x480. The DPI stays the same at 72 DPI.

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You ALWAYS want the image size at the biggest there is.

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Not true. It depends upon what you want to do with the picture. I have a 2.1 MP digicam and take most of my pictures at the lowest resolution (640x480) which I then have to compress to 1/2 size (320x240) to fit in my reviews pages.

If I want an extreme closeup, I set the camera to it's largest setting (1600x1200) and take a macro photo, then crop to the area I want to show using graphics software.

If you're printing them, then yes, you want the largest resolution. If you're putting them on the web, the lowest resolution will usually be OK. If you want to use the pictures as wallpaper on your PC, or show them only on the PC as a slide show, you can set the camera resolution to your desktop size.

Most of my "non-website" photography is taken at 1024x768 for display on my PC unless the subject is far away or very detailed; in which case I bump it up to the max.

I leave my camera on "fine" all of the time as this equates to less jpg compression and therefore more detail.

Even if I'm making an 80x80 CPF avatar I shoot at 2400x1800 and reduce size, etc., in Photoshop.

That way of at any point I want to use a bigger version on a page somewhere, or print it, I have a usable original to work from.

If what I use on a page is going to be 320 across I'll still shoot at a larger size and reduce for the specific use. The image from the camera IS your "negative" and the image on-line is equivalent to a snapshot print.

To do anything else (purposely shoot at reduced resolution) would be like printing a negative to 3 1/2 x 5 inches and then burning the negative.

If one wants to make an 8x10 for the mantle later, one is stuck with trying to copy and enlarge the snapshot, with horrid results, because there is no high quality original ("negative").

If one accidentally takes a once-in-a-lifetime picture, I suspect that one would want the best original possible, not some tiny thing.

Reminds me of something we used to say in photo interpretation: "image quality does not seriously degrade target identification" which translates to "lousy picture" in English ... /ubbthreads/images/graemlins/smile.gif

On most digicams, the standard, fine, superfine refers to the amount of resolution while image size is usually a separate setting. I agree, shoot at the highest, you can always resize down. Just like if I do image editing, I always make sure it is on a copy of the original so the original is unchanged in case I make a screw up.

The other issue here is the one of JPEG compession and noise. Which do you think will sample an image down better, Photoshop or the CPU in your camera? Although almost nothing is ever absolute, I'd bet 9 times out of 10 your computer will sample a JPEG down 'better' than your camera.

I used to think my dads camera has CRAPPY image quality but then I realized that a large part of it was because he shoots in the larger of 2 image size choices, but at highest compression. I'm giving him more memory for Christmas so he can shoot on the cameras highest setting /ubbthreads/images/graemlins/grinser2.gif

QB,
I am not saying to host pics that large. LOL
Just take them at full size. And keep a copy of th efull size.

Edit them to go on the web, or by email. But always have your full size original.

And besides, with something like ACDSEE, it can be a huge size pic, but it will compress the file size down to 230 KB and still have a great looking 2400 X 2000 pic.

I think the key point is that resolution is separate from file compression, and the terms superfine, etc, refer to compression.

For example, my Canon 3MP can shoot at resolutions of
2048 X 1536 pixels
1600 X 1200
1024 X 768
640 X 480
and some others, and they ALL allow 3 levels of file compression (superfine, fine and normal). The more compression, the smaller the file size, but the greater the artifacts.

So the 2048x1536 pixel resolution at superfine (minimal compression) results in a file size of about 1.6MB, at fine about 900MB, and at normal, about 450KB. They all have a resolution of 2048x1536. I assume other manufacturers have similar adjustments. I guess an uncompressed 3MP would be over 9MB and RAW even more?

Personally, I saw very little difference moving from a 2MP Canon to the 3MP Canon, so maybe 3 to 4MP might not be very noticeable, depending on your pickiness, compression settings, etc. On my Canons, I could tell no difference between Superfine and Fine compression on extreme Photoshop blowups, so I normally use Fine and save filespace. YMMV. Normal setting was obviously bad to me, so I never use that. And I also always use the highest resolution, save that, and resample if I need smaller images.

IMO, if you are just starting out, and maybe not a picky photo pro, and want to save money, go ahead and get the 3MP, shoot in the highest (3MP) resolution, and test the compression levels to see what you can tolerate.

Wow. Lots of good information here. Thanks and 2 more questions:
1.) Does the amount of compression (normal, fine, superfine) change the working speed of the camera? That is, does compression slow down the camera because it has to process (compress) the image more? Or does it slow down because it has to transfer a larger file to the memory card?

2.) CNC Dan---What do think of the A80? Is there too much shutter lag for your taste?

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and the terms superfine, etc, refer to compression.

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Not always. Depends on the camera. Be sure to consult your owners manual.

I THINK, most the time, the larger file will take longer to do, rather than the greater compression.

Shutter lag.... all digicams are kinda bad about this.
You should be able to find the delay times though.
I think the A70 and 80 are alot faster than my old A10 though. You just have to get used to it to time things out.

Goto Steve's Digicams the times are probably there.

Another quick note: The Canon G3 takes cleaner pictures than the Canon G5. This is because they added another megapixel on the same size sensor. If you compare pictures from each other these cameras, you will notice more noise and chromatic abberation in the G5 shots. Just something to think about...

I have an Olympus C-5060 Wide Zoom 5 megapixel camera for sale if you are interested.

I didn't know shutter lag was bad. I thought it was a feature, not a bug. /ubbthreads/images/graemlins/smile.gif It gives me time to take my finger off the button when taking long exposure pictures. Cheaper and handier than a cable release.

eluminator,

LOL, well thats one way of looking at it I guess.

Drove me CRAZY when I got my first digicam (A10)

But even my $500 HP digicam does it.

Its fine till you hand the camera to someone else that doesnt have experience with digicams. hehe

If I bought a new one now, it would be the Canon A80.

I eventually want a nice SLR digicam, but, thats about $1300 to... well, ALOT.

I've found that if I shut off the auto focus and define the focus maually in the menus, "shutter lag" virtually disappears.