silverfast scanning

[walterb]

I know this subject has been discussed many times, but I am an old guy trying to learn with this new technology. I am useing an epson 4990 with silverfast AI 6.4 then on to photoshop. I am scanning tri x 4x5 with settings in silverfast as follows:
scan type 48 bit color, output size 16 x 12.7. If I set the dpi which I assume is the same as ppi at 300 I get a file size of 104.75 mbytes, at 600 dpi file size is 419.02 mbytes, at 1200 file size is 1676 mbytes. I have tried the 1200 setting and the computer told me I didn't have enough RAM. I have 2 gig of ram. I have read on previous threads of scanning at 2400 ppi. Totally confused. Any help would be appreciated.

Walterb

[ostreet]

It's all an issue of scaling. Silverfast conveniently does the math for you so you don't have to worry about it. If your final output size is 16x12.7 you'll want to choose a dpi that you would like to print at. 300 is generally considered to be the sweet spot, but in my experience anywhere from 180 to 360 is fine depending on the application and printer. Anything beyond that is overkill and a waste of your time and computer's resources.

Let's do some quick math. We'll assume nice round numbers here to make it easy. Say you want to scan your 4x5 to make an 8x10 print. We know that 300dpi is our goal. So we could scan this neg in a couple different ways. 1) Tell Silverfast you want an 8x10 (output size) @ 300dpi. You'll get a file that is 2400x3000 pixels (8x300=2400, 10x300=3000). 2) Leave your output size at 100% but set your dpi to 600. You'll get a file that is 2400x3000 pixels (4x600=2400, 5x600=3000). The same as before. Open said file in photoshop and change the Image Size to 8x10 @ 300dpi. The file does not change...it is still 2400x3000 pixels. If you're still confused try looking here for a more in depth explanation.

[ostreet]

A couple more things...

When people recommend scanning @ 2400dpi what they mean is to leave the scaling alone (default 100% or ouptut size the same as the input size) and resize in PS as needed. The philosophy here is to scan once at the highest resolution that your particular scanner is capable of and you won't have to scan again later if you decide you want a larger print at some later date. Not bad advice if you have the computer horsepower for it, but leave your scaling to 100%. Of course, if you're scanning 48bit color, your going to have a hard time handling that file cause it will be huge.

My advice, since you are new, just stick to scanning for your final desired print size at 300dpi and be happy. You may have to rescan a few negs down the road, but the practice could actually be good for you. For what it's worth, if you're printing much beyond 16x20, you'll probably not want to use your scans from your 4990 anyway. If you are printing large, invest in a professional scan...you'll be much happier.

Eric

[Joanna Carter]

I know this subject has been discussed many times, but I am an old guy trying to learn with this new technology. I am useing an epson 4990 with silverfast AI 6.4 then on to photoshop. I am scanning tri x 4x5 with settings in silverfast as follows:
scan type 48 bit color, output size 16 x 12.7. If I set the dpi which I assume is the same as ppi at 300 I get a file size of 104.75 mbytes, at 600 dpi file size is 419.02 mbytes, at 1200 file size is 1676 mbytes. I have tried the 1200 setting and the computer told me I didn't have enough RAM. I have 2 gig of ram. I have read on previous threads of scanning at 2400 ppi. Totally confused. Any help would be appreciated.

1. Are you using Windows or a Mac?

2. If you are using Windows, which version?

3. How much spare disk space do you have?

[Brian Ellis]

Why are you scanning b&w film as color? Some years ago that used to be recommended by some people but IMHO it was of questionable value even back then with 4x5 and in any event has been rendered unnecessary by later technology. Forget the color, scan it as 16 bit b&w and right off the bat you'll have a huge reduction in file size. You're also pushing what IMHO are the limits of quality prints from 4990 scans at your print size. I'd scale back a little at first, maybe to roughly 11x14, then work your way up if necessary.

[Doug Fisher]

Are you by chance using the ICE feature? If so, try turning it off and you might find it then allows you to make the scan. Just a thought because the same issue shows up with medium format scans at high resolutions when ICE is turned on. Turning ICE off often makes the issue go away.

Doug
---
www.BetterScanning.com

[walterb]

joanna

I have windows xp with about 280 gbytes of free space.

walter b

[walterb]

A couple more things...

When people recommend scanning @ 2400dpi what they mean is to leave the scaling alone (default 100% or ouptut size the same as the input size) and resize in PS as needed. The philosophy here is to scan once at the highest resolution that your particular scanner is capable of and you won't have to scan again later if you decide you want a larger print at some later date. Not bad advice if you have the computer horsepower for it, but leave your scaling to 100%. Of course, if you're scanning 48bit color, your going to have a hard time handling that file cause it will be huge.

My advice, since you are new, just stick to scanning for your final desired print size at 300dpi and be happy. You may have to rescan a few negs down the road, but the practice could actually be good for you. For what it's worth, if you're printing much beyond 16x20, you'll probably not want to use your scans from your 4990 anyway. If you are printing large, invest in a professional scan...you'll be much happier.

Eric

Thanks, Now I understand I appreciate your help
Walter

[walterb]

1. Are you using Windows or a Mac?

2. If you are using Windows, which version?

3. How much spare disk space do you have?

I am using windows xp with about 280 g bytes of spare space wit most of this on an external hard drive.

walter

[walterb]

Why are you scanning b&w film as color? Some years ago that used to be recommended by some people but IMHO it was of questionable value even back then with 4x5 and in any event has been rendered unnecessary by later technology. Forget the color, scan it as 16 bit b&w and right off the bat you'll have a huge reduction in file size. You're also pushing what IMHO are the limits of quality prints from 4990 scans at your print size. I'd scale back a little at first, maybe to roughly 11x14, then work your way up if necessary.

I was under the impression scanning in color was the way to go. I will scale back to
b&w and reduce the file size.

Thanks for the helpful info.

walter