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Dthind · member Member # Joined: 12 Dec 2000 Posts: 436

Are there any consumer level digital cameras with a DPI other than 72 ?

I understand the megapixel thing, but everything is at 72 DPI. ?

waylon · Posted: Wed Jun 13, 2001 7:13 am

DPI is absolutely meaningless when looking at camera stats. Just look at what resolutions the camera can take pictures at. 2048x1536 is 2048x1536 no matter what. If you're DPI is set to 72, it'll print a picture 28" wide. If it's set to 600, it'll be 3.5" wide. That has nothing to do with the camera.

Dthind · member Member # Joined: 12 Dec 2000 Posts: 436

OK, so I will play stupid.

If I take a picture with the digital camera and the normal slr, and I scan the print from the slr, the scan at 600dpi has better image quality than the digital camera. The assumption is that I have the same image size in kb.

The digital camera (when I zoom in), is more pixelated.

Am I missing something here ?

Anthony · Posted: Wed Jun 13, 2001 9:50 am

More important in digital cameras than the number of pixels is if it has controls for shutter speed and fstop. Some of the newer ones have that, and it's important for taking good photos.

waylon · Posted: Wed Jun 13, 2001 9:57 am

Ok, first off, I'm not completely up on my camera terminology. I'm assuming an slr is just a standard 35mm (or whatever) camera, right? So going on that assumption...

Let's say you scan the print at 600dpi. How big was the print? Was it 6x4? 5x3? Or did you scan the negatives? When you're talking about image quality, you have to talk in terms of pixels, because DPI - dots per inch - is meaningless if you don't know how many inches you're working with. If you scan in your negatives (about 1" wide) at 600dpi, your image will be 600x400, which isn't too impressive. If you scan in the 6x4 print, it'll be 3600x2400, which is pretty significant, but if you zoom all the way in it'll probably be pretty blurry (as opposed to pixelated.)

When you're playing with the digitial camera, you're not scanning anything in. You're working in pure pixels, which have nothing to do with inches, or centimeters, or any other unit of measurement. Like I said before, 2048x1536 is the same no matter what DPI you're working at, because it's raw data. The only time DPI comes into play is when you want to print the photo out - and that's a function of your printer, not the camera.

So as long as the cameras you're looking at can do the same resolution, the photos will have the same quality - the only difference being that some cameras have better lenses, more control over aperature and shutter speed, etc.

Make sense?

Dthind · member Member # Joined: 12 Dec 2000 Posts: 436

waylon,

Thanks, this makes more sense. SLR (Single Lens Reflex), or 35mm camera, generally this means a camera with a removable lens. But not always.

Part of the problem is that my Nikon FG with an 80mm lens takes quality pictures and my Nikon coolpix900 has a low quality lens, that has almost no options.

gowansy · Posted: Wed Jun 13, 2001 11:14 pm

Ok, i have a Fujifilm, 4.3million pixel output, USB, and it says on the box the image file size is 2,400 x 1,800 pixels. Is that good, and wtf does Pixel Output mean?

waylon · Posted: Wed Jun 13, 2001 11:59 pm

gowansy: Yeah, that's a pretty good resolution. Pixel output is, well, how many pixels are saved per picture. (Basically, multiply 2400 by 1800, and you get 4.3 million.)

Storing pictures at that resolution is fairly easy nowadays. What's most important is the quality of your camera's lens. If they put a cruddy lens on there, your super-high-rez photos will all be blurry when you zoom in, making the extra resolution pointless. Unfortunately, I don't know much about the quality of one lens verses another - just that it starts becoming an issue for high-end digital cameras.

Incidentally, I've got a Canon Powershot G1, and it rules.

gowansy · Posted: Sat Jun 16, 2001 8:11 am

My dad used to have a brilliant Canon camera, unfortunatly i cant remember the name......it cost him �900 because it had 1 of the best lenses at that time, worth about �500 now though

It was silver

black_fish · Posted: Sat Jun 16, 2001 11:04 pm

Allright... a picture 2400 by 1800 in 300 dpi in Psp is 8x6 inches. That means if you want to use your photo to be printed in a magazine for example the maximun size the picture can be is 8x6" (knowing that most printed work is done in 300 dpi). So sure the size in pixels is more relevant than the dpi resolution but you still have to know what will be the maximum size printable at a 300 dpi res. If you want to print a big poster at 300 dpi, you better get a better camera (one that goes over 2400 by 1800)...