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At what dpi do you scan your trannies at for decent results-for use on web and printing, also what dpi do you print the results?

Trannies should be scanned at a resolution that will give you the desired print size at either 240dpi or 300dpi.

This means that, if I want to print a 5x4 trannie at 240dpi, I will scan it at 1200dpi which will give me an image 5 times the size of the trannie (1200 / 240 = 5); IOW 25x20 which is larger than the A3+ paper that I usually print on (19x13).

I will then save the file but then use something like Genuine Fractals to reduce that size, just prior to printing, but without saving that change to the file.

The Epson printer driver that I use does not state what dpi it is printing at, it just uses titles like Photo (2800dpi) or Best Photo (5600dpi). I always print at the maximum resolution available on the printer driver, but this does not affect the fact that the file should be kept at 240 or 300dpi.

As for web images, I save them at 96dpi using Photoshop's Save for web option, but whatever ekse you do, you need to convert the image from the working profile in Photoshop, which should be ProPhotoRGB, to Adobe RGB, otherwise you can get some wierd colours on other peoples' monitors.

I have a few other tidbits of information to add, some of which may contradict yours Joanna, sorry!

The Epson drivers ( at least 2100/2200, 4000, 4800 etc ) internally work at 360ppi at all resolutions, or 720ppi if printing at 2880dpi. I print at 1440dpi ( very little noticeable difference from 1440 to 2880, except in ink usage ) so I always send my images to the printer at 360ppi, if I didn't, the driver would re-interpolate to 360 anyway.

I don't have the developer manuals for these new breed of 5600dpi printers, so I cannot say for sure their internal ppi.

When saving for web, you should always convert to sRGB, which is the "default" colourspace of the web, as it's the lowest common denominator. sRGB claims to represent the "average uncalibrated Windows display". Many monitors have an sRGB setting to characterise their output, 95% of digicams are sRGB, Adobe RGB is quite specialised, and a monitor capable of showing the full AdobeRGB gamut has only just reached the market, and will cost you a lot of money! Anything web based, assume sRGB. Sorry, I'm a bit of a colour-management/printing geek

With regards scanning, I personally find it a tiresome chore as I can never quite get the sharpness I want, so I subscribe to the "Scan Once, Print Many" philosophy. I scan my 5x4 at 3200dpi ( which should be enough for a 40x30 ) and downsample just as Joanna suggests to the desired print-size. File sizes are huge though

DJ wrote:The Epson drivers ( at least 2100/2200, 4000, 4800 etc ) internally work at 360ppi at all resolutions, or 720ppi if printing at 2880dpi. I print at 1440dpi ( very little noticeable difference from 1440 to 2880, except in ink usage ) so I always send my images to the printer at 360ppi, if I didn't, the driver would re-interpolate to 360 anyway.

Most manufacturers' drivers do something along those lines, afaik.....
Have a look at Qimage, which is a cheap printing/SW rip solution. THere is a lot of information on this particular thing on their website.

DJ wrote:With regards scanning, I personally find it a tiresome chore as I can never quite get the sharpness I want, so I subscribe to the "Scan Once, Print Many" philosophy. I scan my 5x4 at 3200dpi ( which should be enough for a 40x30 ) and downsample just as Joanna suggests to the desired print-size. File sizes are huge though

Similar thing here. I scan everything at 2400 (my scanner doesn't really pull more out beyond that anyway), do a couple of basic adjustment layers and then safe the PS file at around 400-500 MB

masch wrote:Most manufacturers' drivers do something along those lines, afaik.....Have a look at Qimage, which is a cheap printing/SW rip solution. THere is a lot of information on this particular thing on their website.

Qimage is an application written by Mike Chaney, he's a good guy and I've had many an interesting chat with him on printing. I don't think Qimage is a RIP, it's a printing application, which still uses the printer drivers supplied by the manufacturer. The difference is that Mike has researched the details of all those drivers and Qimage will prepare the ideal data for each driver by doing the interpolation, colour management and print sharpening within Qimage. Many people printing images don't know or don't want to know about that, so if you don't want to fiddle with all that stuff yourself, Qimage is a great way to get better prints.

Personally, I like to tinker so I do this myself

Another product you might be interested in is QuadToneRIP, by Roy Harrington. This one is a RIP ( I'm pretty sure ) and bypasses the printer drivers. It's specifically designed for printing B+W images, and you can create your own "curves" and blend different curves together ( say 15% sepia 85% neutral ). You can create some stunning monochrome images with it, I use it for all my B&W digital prints, highly recommended. It's a shareware product you can try out for free and register ( $50 ) if you decide to use it regularly. You'll need a spectrophotometer/densitometer to properly create your own curves, but there are quite a few bundled with it.

masch wrote:Similar thing here. I scan everything at 2400 (my scanner doesn't really pull more out beyond that anyway), do a couple of basic adjustment layers and then safe the PS file at around 400-500 MB

Mine are typically 920mb without ajustment layers