canon twain driver?'s

[chillpill]

This may be a stupid question but please bear with me as I'm very new to post processing. I've had my d30 for 8 months but just recently begin shooting in the manual modes and using raw images. I currently use the canon twain driver software to import my images into photoshop 6.01. Under the preferences for the canon software is a setting for dpi. Is there an optimal number this should be set for when converting to linear or non-linear tiff, and why?

Thanks,

Chillpill

[Dick]

"dpi" really has no impact on what you import from the D30 into PS6. Image size "height", "width", and "dpi" are really for output. You import pixels into PS and you use Image Size to tell output devices (printers, web browsers) how to display the image.

I typically resize my D30 images to 6"X4" at 360dpi as this makes lovely proofs without pixel loss on my Epson printer. I typically print at 360 dpi and publish to the web at using the standard 72dpi.

[TulsaRod]

How about using the photoshop le edition that comes with the camera?
D30 images, I have to change the image to 8 bit to work on it.
Am I doing this right? Any optimal settings? Any output size better than others?
Thanks for any tips :)

[Dick]

PS6 only has a few operations that are 16 bits so I suspect PS LE isn't hugely different. From what I have read the D30 images are produced at 12 bits and the human eye can probably detect something like 10bits. The general view is that making color adjustments in 16 bits allows more accurate color than 8 bit but that it is subtle.

You can do great things in 8 bits. If you take your photos in RAW and store these images unedited then you can come back to these images at a later date when you have more capability in your photo editor.

The issue with PS going to 16 bit across the board is processing time. Some filters already take a long time on a big photo and this time would be at least tripled with 16 bit color.

[Dick]

In regard to ouput resolution.

72dpi is the accepted standard for web output. Until more capable monitors are widely available I suggest you stick to 72dpi.

It is generally agreed that print quality is significantly improved up to printer resolution of 1440 dpi and printing at 2880 dpi probably isn't worth the time and ink in most prints.

Output files to an ink jet printer however are not produced at these resolutions. The human eye can not resolve this level of detail. Output files to an inkjet are usually either 300dpi or 360dpi. Anything beyond this is a waste of disk space. The extra resolution in the inkjet is used to produce a very fine and precise representation of the lower resolution photo image.

[rojoyinc]

Chill,

Do yourself a BIG favor and pick up a flash card reader (about 40.00) for your computer. Plug it into a USB port and then to move files from the camera to the computer simply drag and drop them. (CF card readers will accept cards from the camera as well as micro drives). These cards and microdrives appear on your desktop just like a hard drive. Open their folder and drag over from the CF card/microdrive to your hard drive.

(no twain driver is needed for this)

Then download a program called "Breeze Browser" at www.breezesys.com (register it... it's about 35.00 if I recall right) This will allow you to view thumbnails of all your raw files. When you get one you want to convert to TIF or JPEG (or if you want to convert all the images in the folder) it will help you make the conversion quickly and easily.

Once they are in a useable format (I prefer tif) you simply load and work on them in photoshop as needed.
Breeze browser will let you set in it's prefrences the dpi you want to use during the convertion. You can set it to anything you like... 72dpi (for web use) or 300 dpi for easily dumping the images to a printer.

Like stated above - dpi is irrelivant because it's not a contstant. File size is what matters. (the large the file the more data it contains and the large the image can be without loosing quality). The dpi can be changed in photoshop. (you can specify the desired dpi and image size depending on your needs). 72dpi for website computer image viewing, 220-300 dpi for output to a inkjet or for having photos made at the lab.

The dpi number set doesn't really matter unless you want to save the step of changing the dpi later. It's not a constant so dpi really doesn't matter.

Most people don't understand digital imaging and put a lot of stock into dpi. When I try to explain that it's file size that counts they don't get it.

I just got a program called Qimage and in it's help file there is a "FAQ" this is the top question... it might help as well.

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Q: When I use some image editing software, it reports that my photos are 72 DPI. Will this affect my printouts and do I need to "resample" or "interpolate" these images up to 300 DPI before using Qimage Pro to print them?

A: This is a misleading concept that we wish some image editing programs wouldn't make so confusing. Although your image editing software may report 72 dpi for a particular photo, digital images simply have no DPI, because images (by themselves) have no relation whatsoever to "inches". Relating images from digital cameras to a physical print size like some photo editing packages do, is simply confusing and a rather useless concept since they do so without consideration of what size you actually intend to print the photo in the first place! In other words, reporting 72 DPI for a 2048 x 1536 resolution image is simply choosing a "default" print size of 28.44 inches by 21.33 inches for absolutely no reason, because editing a photo should not necessarily be linked with a specific print size. You can "worry" about print size and interpolation at print time. Stored images such as JPG, TIF and other formats simply have a "resolution" which denotes the number of pixels in an image. Obviously, you cannot "translate" image resolution such as 2048 x 1536 into dots per inch (DPI) until you select a print size for that image. For example, if you print that 2048 x 1536 image at a width of 6 inches on your printer, you will get a print that is approximately 200 DPI (2048 pixels divided by 10 inches). In contrast, if you print the same image at 14 inches wide, you'll get a print that is about 150 dpi. Qimage Pro is designed to print images at whatever size you specify, and can automatically ensure that your original images never drop below a certain DPI threshold when you print. Once you set your minimum DPI, you never have to worry about it again! It just doesn't need to be any more complicated than that! For more information on this auto-interpolation, see "Options", "Print Interpolation" from the main window of Qimage Pro.

________ end paste

You can select any dpi you want during the conversion, the end result will be the same. Because the *file size* will be the same. It is the size of the file on the disk that matters. A large file will contain more data which can then be used to make larger prints. If you don't have enough data for the large print size you desire, you will need to *upsample* the image... this will add computer generated pixels to the file to increase it's file size. Since these computer generated pixels are averaged into the image by the computer - they do not translate to 'actual recorded detail in the original image" and upsampling to much will result in a soft looking image that lacks detail. So we should use restraint in upsampling.

Hope this helps!
Ron

[chillpill]

AAAAAHHHHHHH!

I get it now.

Thank You All. It's just incredible how much I've learned on this forum.

Thanks Again,
Chillpill