Digital Enlargments

[Texascruisers]

We just returned from Alaska and took a lot of photos. When I enlarged some, they were very grainy. I exposed them at high resolution. But not uncompressed. Any help on this matter would be greatly appreciatted.

[tee_wrecks]

First, what film speed equivilant did you choose? As with film, higher speeds produce more "grain" which is actually digital noise.

 

Second, what software do you use to edit/print he photos? Most photo enhancement programs offer a digital noise filter that will help somewhat.

 

Finally, what size/resolution did you select in your printer driver and what size prints did you make?

 

Regardless of the resolution you shot at, if you didn't set your printer settings correctly you're most likely going to get grain. Example: If you are printing an 8X10 print of a file that was shot at high res on your camera, be sure the resolution on your printer settings is at least 180 dpi. If you print it at 72 dpi which is the common selection for images that will be e-mailed, you'll be able to connect the pixels with a magic marker. Try a sample print at different dpi settings on your printer setting screen and see what happens. (Don't forget to check the print output size after you change the dpi, it will most likely change)

 

There is really a lot more to printmaking than that but at least it's a starting point. Good luck and good printing

[Texascruisers]

First, what film speed equivilant did you choose? As with film, higher speeds produce more "grain" which is actually digital noise.

 

Second, what software do you use to edit/print he photos? Most photo enhancement programs offer a digital noise filter that will help somewhat.

 

Finally, what size/resolution did you select in your printer driver and what size prints did you make?

 

Regardless of the resolution you shot at, if you didn't set your printer settings correctly you're most likely going to get grain. Example: If you are printing an 8X10 print of a file that was shot at high res on your camera, be sure the resolution on your printer settings is at least 180 dpi. If you print it at 72 dpi which is the common selection for images that will be e-mailed, you'll be able to connect the pixels with a magic marker. Try a sample print at different dpi settings on your printer setting screen and see what happens. (Don't forget to check the print output size after you change the dpi, it will most likely change)

 

There is really a lot more to printmaking than that but at least it's a starting point. Good luck and good printing

Thanks for the info Tee Wrecks, I am a newcomer to digital photography and have a lot to learn. Changing form film format to digital is a big jump. I think I will buy digital for dummies as a start.

[judynorth]

One easy way to see if your digital picture file will give you a good enlargement is to look at the size of the file. If it is over 1 MB you should get a decent 8x10 print. This is assuming that you selected photo quality on your printer and used photo paper. It is also assuming that you have a photo quality printer (most of them now will produce decent photo prints). We printed a picture of about 2 MB as a 13x17 print and it was spectacular. It was printed on a large format Epson 2000 on matte photo paper. The camera was a Panasonic FZ20 with 5 MP.

[zackiedawg]

I've always used a basic rule when shooting digital photography - use whatever the camera's maximum resolution capability is, and buy a large enough memory card to support the number of photos you'll want at the highest resolution.

 

Sure, you don't need 5-10MP to display a shot on your computer screen - nor for making 4x6 prints. But shooting in maximum resolution allows you to A) make very large prints of a shot you fall in love with, B) digitally crop in on a small section of your photo and still retain good enough resolution to print, and C) reduce the amount of visible noise in smaller prints up to 8x10.

 

Once that is solved...then as some have mentioned, the ISO will be the next factor. All digital cameras will produce more grain, or noise, at higher ISOs. If you are shooting with a large DSLR type digital camera, their larger sensors will be capable of shooting reasonably noise-free at higher ISOs, but most point-and-shoot digitals will have some pretty serious and uneven noise even at ISO400. Whenever possible, choose the lower ISOs when shooting, only raising it when you need the speed or the light.

 

Also, digital cameras are affected by heat. In Alaska, that's rarely a problem ( ;) ), but in general, the hotter a sensor inside a digital camera gets, the noisier your shots will be. leaving a camera on for extremely long periods of time, leaving it in direct sunlight, or in a heated room or car would all contribute to noisier shots.

 

In post processing, there are some great programs capable of removing most of the noise from a shot, without having to get into learning advanced photo editing software. Sure, Photoshop, Paintshop Pro, and other such programs will include these functions, but they are more for someone who wants to play around in post processing their photos. Instead, look for great programs like Neat Image, Helicon, Noise Ninja, and the like. Many of these companies offer a basic free version of their software on their site which will work fine for removing noise from shots without any other editing needed. If you decide you like the software (some of these are very simple to use...open the photo, click one button, adjust a slider to fine tune, then save), you can purchase their full suite which will often include more ocntrol over the noise removal, plus red-eye removal, purple-fringe removal, straightening tools, etc.

 

One other note on noise: There are many types, but the two primary ones I suspect you are referring to are 'graininess' from high ISO, sensor heat, etc. as described above, and 'artifacts' which are completely different.

 

Artifacts usually are weird extra pixels, lines, and jaggies that appear around edges, contrast borders, and color changes. Pixellation will make straight lines look like jagged edges. There are several causes for this, and a few ways to prevent it.

 

First - resolution. If you are shooting in a low resolution, and printing large, the photo may not have had a high enough resolution to support such a large print. A pixel is a single dot of color information for your photo. When you blow up a picture, you are blowing up each pixel. Pixels can be almost microscopic in size...resolution represents the number of pixels it takes to make up your photo. If your photo was taken at 600x800 (1/2 MP) pixels, and you blow that up to an 8x10...every inch of photo has 80 pixels across, and 75 pixels from top to bottom. Compare that to a photo with a resolution of 1920x2560 (5MP) pixels: printed at 8x10, each inch has 256 pixels across and 240 pixels top to bottom. Many many more pixels are squeezed into that inch. So the higher resolution photo could be blown up 3.2x larger and still have the same quality.

 

The other culprit for artifacts and jaggies - saving the file! Most digital photos are taken and saved in a format called JPG - which is a compressed image file. Compressed files are fine for quality pictures from the camera - they've only been compressed once and still have high quality. But where many people go wrong and don't realize is when they open a compressed JPG picture, edit it in some way, then save it again. And sometimes they'll do something and save it a third time. With a JPG, the photo is being re-compressed every time you open it and resave it. So if you open an already-compressed photo (let's assume it is 20% compressed), and resave it as a JPG, it will now be a 20% compressed version of a 20% compressed photo. Do it again, and it's a 20% compression of a 20% compression of a 20% compression. You can see where that can get pretty bad! You keep compressing, losing image quality every time...the end result can be a messy, noisy looking shot.

 

Hope that helps without confusing too much. Feel free to ask any questions if you didn't understand anything, or need to know where to find some of those programs for noise removal.

 

Good luck.

[judynorth]

The other culprit for artifacts and jaggies - saving the file! .... You keep compressing, losing image quality every time...the end result can be a messy, noisy looking shot.

 

One way to avoid this is to save the edited file in the native format of the editor. I use PhotoShop Elements 3 for image editing and save the picture as a .psd file until I am finished and ready to print. I often print directly from PE3 to avoid compressing the file again and losing quality.

[Texascruisers]

I've always used a basic rule when shooting digital photography - use whatever the camera's maximum resolution capability is, and buy a large enough memory card to support the number of photos you'll want at the highest resolution.

 

Sure, you don't need 5-10MP to display a shot on your computer screen - nor for making 4x6 prints. But shooting in maximum resolution allows you to A) make very large prints of a shot you fall in love with, B) digitally crop in on a small section of your photo and still retain good enough resolution to print, and C) reduce the amount of visible noise in smaller prints up to 8x10.

 

Once that is solved...then as some have mentioned, the ISO will be the next factor. All digital cameras will produce more grain, or noise, at higher ISOs. If you are shooting with a large DSLR type digital camera, their larger sensors will be capable of shooting reasonably noise-free at higher ISOs, but most point-and-shoot digitals will have some pretty serious and uneven noise even at ISO400. Whenever possible, choose the lower ISOs when shooting, only raising it when you need the speed or the light.

 

Also, digital cameras are affected by heat. In Alaska, that's rarely a problem ( ;) ), but in general, the hotter a sensor inside a digital camera gets, the noisier your shots will be. leaving a camera on for extremely long periods of time, leaving it in direct sunlight, or in a heated room or car would all contribute to noisier shots.

 

In post processing, there are some great programs capable of removing most of the noise from a shot, without having to get into learning advanced photo editing software. Sure, Photoshop, Paintshop Pro, and other such programs will include these functions, but they are more for someone who wants to play around in post processing their photos. Instead, look for great programs like Neat Image, Helicon, Noise Ninja, and the like. Many of these companies offer a basic free version of their software on their site which will work fine for removing noise from shots without any other editing needed. If you decide you like the software (some of these are very simple to use...open the photo, click one button, adjust a slider to fine tune, then save), you can purchase their full suite which will often include more ocntrol over the noise removal, plus red-eye removal, purple-fringe removal, straightening tools, etc.

 

One other note on noise: There are many types, but the two primary ones I suspect you are referring to are 'graininess' from high ISO, sensor heat, etc. as described above, and 'artifacts' which are completely different.

 

Artifacts usually are weird extra pixels, lines, and jaggies that appear around edges, contrast borders, and color changes. Pixellation will make straight lines look like jagged edges. There are several causes for this, and a few ways to prevent it.

 

First - resolution. If you are shooting in a low resolution, and printing large, the photo may not have had a high enough resolution to support such a large print. A pixel is a single dot of color information for your photo. When you blow up a picture, you are blowing up each pixel. Pixels can be almost microscopic in size...resolution represents the number of pixels it takes to make up your photo. If your photo was taken at 600x800 (1/2 MP) pixels, and you blow that up to an 8x10...every inch of photo has 80 pixels across, and 75 pixels from top to bottom. Compare that to a photo with a resolution of 1920x2560 (5MP) pixels: printed at 8x10, each inch has 256 pixels across and 240 pixels top to bottom. Many many more pixels are squeezed into that inch. So the higher resolution photo could be blown up 3.2x larger and still have the same quality.

 

The other culprit for artifacts and jaggies - saving the file! Most digital photos are taken and saved in a format called JPG - which is a compressed image file. Compressed files are fine for quality pictures from the camera - they've only been compressed once and still have high quality. But where many people go wrong and don't realize is when they open a compressed JPG picture, edit it in some way, then save it again. And sometimes they'll do something and save it a third time. With a JPG, the photo is being re-compressed every time you open it and resave it. So if you open an already-compressed photo (let's assume it is 20% compressed), and resave it as a JPG, it will now be a 20% compressed version of a 20% compressed photo. Do it again, and it's a 20% compression of a 20% compression of a 20% compression. You can see where that can get pretty bad! You keep compressing, losing image quality every time...the end result can be a messy, noisy looking shot.

 

Hope that helps without confusing too much. Feel free to ask any questions if you didn't understand anything, or need to know where to find some of those programs for noise removal.

 

Good luck.

Thanks for the help Justin, as I stated in earlier posts, I am new to digial photography. Your post has helped me alot. I have so much to learn. You seem to know alot about the field of digital photos. Please feel free to offer me any knowledge you have on this subject. I am eager to learn. Thanks again.