How to get a higher pixel count from a film image

[gb hill]

I shoot a roll of film. When I go have it processed I have the tech guy/gal to put it on a CD, no prints. I notice that the prints on CD read an average of 1818x1224 JPEG,1.24MB. I assume the 1818x1224 to be the pixel count? Some sites like JPG mag. require a minimum of 2200 pixels high or wide & under 10MB. My question is this. Shooting film, how can I get a higher res. print to meet the 2200 pixel minimum requirement? I don't know alot about digital. Hope someone can enlighten my mind a bit!

 

[erikhaugsby]

Get a better scanner. The MP level of a film scan is limited only by the quality of the scanner, not by the film itself. For example, my Nikon CoolScan V ED scans a roughly 24 megapixel image from a 35mm frame.

You might do well to ask the person at the desk if it's possible to scan at a higher quality level, though they often charge more for those extra pixels the scanner creates.

 

[Joe]

Or get a digital camera.

 

[Leighgion]

The resolution that film processors scan at tends to be all over the map. Some give you only very low res scans while charging extra for higher res, while others give you much higher resolution scans at the basic rate. An 1818x1224 scan is okay, but you can extract a lot more good data from a sharp 35mm frame.

Ask your regular processor if they offer higher res scans and shop around a little to see what other outfits are offering if you don't want to buy your own scanner. I've never used Costo's photo services, but I'm told they do high res scans as part of the basic scanning service.

 

[aad]

Yep, either get your own scanner or have the lab do a bigger scan.

My scans are generally 6MP or so, unless I need to print big.

 

[bmattock]

I have never gotten truly hi-rez scans from a one-hour place, period. You can pay a more 'pro oriented' mail order place (or walk in if you live in NY or LA, etc) to do hi-rez scans (and expensive they are, too) or you can buy a scanner and do it yourself.

By having my color print film processed only - no scans, no prints, I dropped the price per roll from around $6 to around $2. It only takes a hundred rolls of film processed to pay for a really nice dedicated film scanner that will do a great job on your film. I called it an investment. It has more than paid itself back to me.

Just some thoughts...

 

[gb hill]

Or get a digital camera.

Ok! to try and understand this ratio of pixel business, (guess you can tell I'm a novice at knowing this). How big a mega pixel camera would one need to take a photo that had 2200 pixels wide or higher resolution?

 

[gb hill]

Also, would a scanner rated at 4800x9600 dpi be a quality enough scanner to give me a hi res print or would it need to be larger?

 

[bmattock]

Ok! to try and understand this ratio of pixel business, (guess you can tell I'm a novice at knowing this). How big a mega pixel camera would one need to take a photo that had 2200 pixels wide or higher resolution?

6 megapixel resolution gives something along those lines.

 

[bmattock]

Also, would a scanner rated at 4800x9600 dpi be a quality enough scanner to give me a hi res print or would it need to be larger?

More than enough. Something at about the pixel count of a 12 megapixel camera, give or take.

Keep in mind - even a 1.2 megapixel digital camera can make a very nice 4x6 print. It is printing LARGER that requires more megapixels.

Ever look at a newspaper with a magnifying glass? It is made up of little dots. They don't look like that when you view the paper at a distance. But if you blew that newspaper page up to fit on a billboard and stood near enough to it, you'd seen nothing but dots. Now consider each of those dots to be a pixel. The more there are in the same size paper, the closer they must be to each other. So you could make that paper into a bill board size and STILL they would be close enough together that it would still look more like letters than dots.

That is what more megapixels does for you, in very rough terms.

 

[gb hill]

More than enough. Something at about the pixel count of a 12 megapixel camera, give or take.

Keep in mind - even a 1.2 megapixel digital camera can make a very nice 4x6 print. It is printing LARGER that requires more megapixels.

Ever look at a newspaper with a magnifying glass? It is made up of little dots. They don't look like that when you view the paper at a distance. But if you blew that newspaper page up to fit on a billboard and stood near enough to it, you'd seen nothing but dots. Now consider each of those dots to be a pixel. The more there are in the same size paper, the closer they must be to each other. So you could make that paper into a bill board size and STILL they would be close enough together that it would still look more like letters than dots.

That is what more megapixels does for you, in very rough terms.

Well that being the case, I assume that dpi means dots per inch. Like square inch maybe? If this is the case then the one hour labs must use small scanners. Understand things a bit better. Thanks, but still more to learn.

 

[Leighgion]

Ok! to try and understand this ratio of pixel business, (guess you can tell I'm a novice at knowing this). How big a mega pixel camera would one need to take a photo that had 2200 pixels wide or higher resolution?

Pixel dimensions and megapixel ratings are fairly straightforward when you get past the fact they're not directly connected to physical size. If you have an image's pixel dimensions, like say 1818x1224, you just multiply them to get the total number of pixels and divide by a million to get megapixels.

1818x1224 = 2,225,232 = ~2.2 megapixels.

My Nikon D40 is a 6 MP camera that delivers 3024x1928 at maximum res, so that level is more than enough for the 2200 pix width requirement. If you look in the detailed specs of any digital camera, it'll give you a full list of the actual resolutions it can shoot at.

Far as scanning your own film goes, I find 2400 dpi scans of 35mm frames produce roughly 6 MP images. The exact dimensions will vary a little. I find it to be a good median of available resolution just in case you want to make normal-sized prints off the scans vs how much space they're eating up on your hard drive. A a 6MP image will produce very nice 8x10's for you, which is about as high as I'd normally think of going.

 

[bmattock]

Well that being the case, I assume that dpi means dots per inch. Like square inch maybe? If this is the case then the one hour labs must use small scanners. Understand things a bit better. Thanks, but still more to learn.

DPI is not the same as pixels, but the concept is basically there. DPI is meaningful when you print.

The problem with the store scanners is not that they are 'small' so much as it is that they take a 'dot measurement' (a sample) too far apart from one another.

If you draw two points, and then fill in the gap in between each point with dots, it does not look like a line - it looks like a bunch of dots. But if you make enough dots, close enough together, then it looks like a line. Unless you look at it with a magnifying glass - then it is back to being dots again.

Higher resolution scanners take more samples closer together. The result is more dots per side (megapixels) but where that really become important is when printing, and then we're talking dots per inch (DPI). The more megapixels you have, the larger you can print without the result looking more like dots than a photograph.

 

[Bob Michaels]

http://www.scantips.com is a great tutorial on scanning, dpi, and all those things. I highly recommend it.

It will not only answer all the questions you have now, but will also answer those you don't know to ask (but should).

 

[Leighgion]

A cautionary note about scantips.com: while what I've read of it is sound far as many principles go, it was written many years ago and thus its discussion of scanner options is antiquated. Not the best place to start learning about scanners in a general sense, as it must be read with some temporal filters.

 

[oscroft]

I assume that dpi means dots per inch. Like square inch maybe?

Not per square inch, just per inch - it's a measure of the dots in a straight line. So 1000 dots per inch is 1000x1000 dots per square inch, unless the resolution in the two directions is different...

...a scanner rated at 4800x9600 dpi...

I've used several scanners that have a maximum resolution that is different in different directions, but using a resolution like that it has to interpolate in the lower resolution direction (so for 4800x9600dpi, it would have to invent and insert extra pixels in the 4800dpi direction to get it up to 9600x9600dpi). And whenever I've tried an interpolated resolution like this the result has been poor, with much better results at the highest genuine optical resolution (which would be 4800x4800dpi in this case - still plenty good enough for the publication requirements you mention)

 

[gb hill]

http://www.scantips.com is a great tutorial on scanning, dpi, and all those things. I highly recommend it.

It will not only answer all the questions you have now, but will also answer those you don't know to ask (but should).

Thanks everybody. And thanks Bob for the link. This will be a big help to me. Leighton said the site is a bit antiquated, but an antiquated explination is probably what I need.🙂