What do they say about scanners in the newsgroup
Film Scanners

Flatbed Scanners

Resolution, what to choose?

Which scanner to buy ?

top of page To top of page
Filmscanners!

red bullet gif image Roger Levit (Rlevit)wrote on Saturday, September 29 in Luminous Landscape Forum: Digital Imaging :
I just got the Canon FS4000 too and the difference between 2400 and 4000 is considerable. Using the Epson 5500 I am gettng scans from slides that are excellent when blown up to 11x17.

The software is great, the film and slide holders first class.

Best of all it costs under a $1,000.
red bullet gif image Dale Cotton (Dcotton) on Wednesday, December 26, 2001 in Luminous Landscape Forum: Digital Imaging :
Very few people have used multiple 4000 ppi scanners. I'll throw out the impressions I formed of the Nikon 4000 during my pre-purchase research. Hopefully others will use them as a starting point for further discussion. Because I work with colour neg film, I finally opted for the Canon FS4000, but it would have been a much closer call if I primarily used reversal film.

Dmax
Based on all I've read and the samples I've seen the Nikon 4000 has greater Dmax than any other 35mm-only 4000 ppi scanner (with the possible exception of the new Minolta that does 4800 ppi). This is crucial to those who primarily work with reversal film.

Resolution
A number of knowledgeable people report having serious problems with film curl / scanner DOF / edge-to-edge sharpness. Getting film strips and mounted slides to lie flat is a recurring issue and the Nikon 4000 seems to be unforgiving. Apparently there is a glass film-holder option and apparently there are problems associated with such holders. Beyond that caveat the Nikon seems to have excellent resolution.

Film-handling
The Nikon 4000 has extensive film holder options, so far as I know more than any other consumer scanner. Apparently it particularly excels in unattended bulk film scanning.

Dust-handling
Perhaps because of the tri-colour LED illumination or perhaps because of the shallow DOF, the Nikon 4000 is often reported as relentlessly bringing zillions more dust motes into sharp focus than anyone would have thought could possibly exist. The 2nd gen of d-ICE included certainly zaps all dust spots and does so with less softening than gen 1; however, from samples I've seen there is still _some_ softening. Most users feel this can be corrected by applying USM, but of course this means a stronger USM setting than would otherwise be needed. (I recommend experimenting with post d-ICE samples to see for yourself.)

Software
The provided NikonScan program is reported to be very thorough. The first 3.0 release with the Nikon 4000 crashed many people's computers almost constantly. Subsequent point releases are edging towards relative stability.

The test images on http://www.imaging-resource.comseem to me to be an excellent launching point for going beyond opinions and subjectivity.


top of page To top of page
Flatbed Scanners

top of page

red bullet gif image Alwin wrote August 29 in newsgroup comp.periphs.scanners :
Hi,

I just purchased the very first Epson Perfection 1250 at Staples. I got it as it was being unloaded onto the dolly. It just arrived on 8/25/01 in the select stores out here in West Los Angeles.

First off, let me just say, that I loved the 1240 and 1640 scanners, they were real commercial workhorses. I would never trade in my 1640 for any of the newer models. It was worth every cent of the $300 I paid for it. So, I unpacked the new Epson 1250 and like other Epson products, the scanner installed right out of the box without a hitch.

Unlike the 1640/1240, the 1250 has an external power supply that has a cord running out of it, thus making the scanner footprint very small.

The 1250 scanner is a 24-bit output scanner with 48-bit internal scanning, contrary to reports that this is a "true" 48-bit scanner. Thus, in all this is actually a 24-bit scanner, thus why it is priced less than the 1240 scanner which is a true 42-bit/42-bit scanner. All in all, bit-depth really doesn't matter once you get past 36-bits, so that's not really my issue here. The quality of this scanner leaves much to be desired.

The first thing I noticed was that this scanner is not particularly responsive. When the Twain program was launched, it took the scanner head a good 30 seconds to preview the image. It took over a minute to actually acquire a full page image at 300 dpi. That is very slow when compared to even cheap UMAX scanners.

The second thing I noticed was the poor quality control. I ended up exchanging this scanner 3 times before I even got a non-defective one and even then this "streaking" defect was still somewhat visible. The first 2 1250's I bought exhibited a defect that prevented image aquisition. Essentially, the image was not visible, because there was red green blue streaking across the image that blotched it out.

This scanner is a far cry from the Epson 1640/1240/640 series.

If you can still find them, buy an Epson 1640 for $200. That's a real gem there at a reasonable price.

Also, I noticed that unlike the 1640, the new scanners are made in Indonesia. The 1640 I own is made in Singapore, where wages and living standards are much higher than they are in Indonesia (and the US for that matter). However, location of manufacture shouldn't matter as long as quality control is kept up to par.

I hope Epson gets it right again because the xx40 series was the only reliable commercial-quality scanner at consumer-level prices available in
Thanks.


red bullet gif image Dan Kreithen wrote on Monday, January 07, 2002 in Luminous Landscape Forum: Digital Imaging :
I have bought and use the 2450 for scanning 120 and 4x5 negatives (black and white). In short, it's a very impressive scanner FOR THE MONEY. It's certainly not the equivalent of the latest Polaroid, Nikon, or Minolta dedicated 120 scanners. However, for black and white negatives, it does a great job of preserving tonal range, if you follow the correct procedure. First, scan with the negative directly on the glass, emulsion side down to avoid Newton's rings.

Next, be sure to scan it as a "Transparency", then average the channels using Channel Mixer in Photoshop (I avoid the blue channel which appears to be very noisy compared to the other two), then invert to get a positive image. Lastly, I have not been able to get Epson's software to display properly on my screen (not sure why), and in any event, it appears as though both the Epson driver and the included SilverFast SE will only give 8 bit output.

Vuescan is well worth the money in this instance, since I believe it preserves full output fidelity. The actual "resolution" of the scanner is in all likelihood not 2400 dpi (probably closer to 2000 dpi based on my anecdotal evidence), but it's more than enough to support a great looking inkjet print from 6x9 negatives at up to 13x19 inch output size, particularly when used in conjunction with Nik Sharpener Pro Inkjet edition. This has been my experience so far, YMMMV.



top of page To top of page
Resolution, what to choose?

resolution, what to choose Mike Fox (mikefox@satx.rr.com) asked 2003-03-11 in the newsgroup comp.periphs.scanners
If we're scanning images so future generations can see pictures of there their ancestors, what dpi should we use?

I have read that there is no use in scanning at a dpi greater than the resolution of the image--say 300 dpi for color prints and 2900 dpi for 35 mm color transparencies. The rational is that you are not gaining more info from the image at higher than those rates. I know others will scan the 4000 dpi for transparenciens.

What should we scan at and why?

Mike

resolution, what to choose Wayne Fulton (Fulton@ScanTips_N0spam.Com) answered 2003-03-11

It is only about enlargement. The desired enlargement factor is the key. There is no other answer.

There is no need to print at more than 300 dpi, because our printers cannot do it, and our human eyes cannot see it anyway. The future will likely improve the printers, but a few years time is not likely to change the humans much. So this is the base line, the reasonable goal.

35 mm film is too small to view directly - it needs enlargement for humans to see it. So we might scan it at 2700 dpi, and scale to print it at 300 dpi, which will print 2700/300 = 9X larger size than the original film, which is about 8x12 inches (near A4 size). If we wanted to print smaller, we could scan with less resolution. If we wanted to print larger, we would need to scan with more resolution. It is all only about the degree of enlargement that we want.

Scanning a 6x4 inch photo, and printing it at 6x4 inches (at original size), requires no enlargement at all, so we can both scan and print it at 300 dpi. The ratio of 300/300 (scanning/printing dpi) is 100% size, meaning, same original size. No more is needed nor useful.

Scanning 8x10 inches and printing 4x5 inches (reduction instead of enlargement, but same concept) requires 150 dpi scanning resolution, to print halfsize at 300 dpi. The ratio of 150/300 dpi is 50% size.

The function of scanning resolution is to produce the degree of enlargement required, at the rate of xxx pixels per inch.

So it is only about the degree of enlargement that we want, to match our goal. However, we can want things we cannot have, for example, trying to scan a photo print to blow it up several times larger is doomed to poor results, because the photo print is only a poor second generation copy of the original negative, and it simply doesnt have it to give.

The original film can give much more. And the film is typically much smaller. This is why film scanners are rated at much higher resolution than print scanners, for greater enlargement, which actually works.

Wayne

http://www.scantips.com "A few scanning tips"


resolution, what to choose DURNFORD KING on Tuesday, May 01, 2001 in Luminous Landscape Forum: Digital Imaging :
I'm using an Epson 1640 scanner that will give me true optical resolution of 1600 dpi and 42-bit color and 14-bit grayscale capture - according to the docs.

I am right now using it to scan 8X10 B&W prints and the occasional 5X7 color print into Photoshop for various kinds of manipulation. I am printing to an Epson 2000P using 11.7X16.5 paper. When I scan the image in I set the target size to fit the paper. I also want to be able to have some of them printed larger on an Iris or some other large format printer so I'm concerned with the total resolution.

Here's the problem.
If I scan at 1600 dpi and a high bit setting, I get files in the 1.2 Gig range which are way too big. I can't even save the image on a CD.

Am I being too fastidious with my resolution? Is there some less demanding approach that will give me the latitude I want? Thanks.

resolution, what to choose Rick Hearn answered on Tuesday, May 01, 2001 in Luminous Landscape Forum: Digital Imaging :
Durnford,
The preferred output resolution for the 2000P is about 240 dpi. (Some folks see enough difference to go to 300 dpi, but 240 is typical.)

Since the magnification ratio from source scan to output size is approximately 1.5 to 1, you need to scan at about 1.5 times 240 dpi which is 360 dpi. Scanning at any higher resolution is unnecessary for the 2000P print sizes.

If you are using a scanner with a native resolution of 1600 dpi and you need a 360 dpi scan, you may find that the scanner works better at an even sub multiple of its native resolution (i.e. 400 dpi in this case).

I would recommend that you do separate scans at higher resolution for the minority of images you want to output at higher resolution. (You should find out ahead of time what the preferred dpi is for the model of Iris they will be printed on.)

resolution, what to choose Michael Reichmann (Mreichmann) answered on Tuesday, May 01, 2001 in Luminous Landscape Forum: Digital Imaging :
Durnford,
Have a look at my article on Understanding Resolution. This should clear things up.

Michael


resolution, what to choose
JJVandJMB wrote in message February 17 2002
My Canon CanoScan FB620U has Optical Scanning Resolution of 600x600 dpi and Maximum Resolution of 2400 dpi. Does that mean the highest dpi I can scan at is 600 dpi (without interpolation)? I'm confused because 600x600 is two numbers, but in the scanner software there isn't a choice for scanning at 600x600 dpi. It only offers choices such as 200dpi, 600dpi, etc. Is 600x600 dpi the same as 600 dpi?

Jefro answered February 17
Welcome to the world of scanner marketing. It gets worse when the two numbers are different.

The two numbers are optical resolution in two different dimensions, horizontal and vertical, though not always in that order. The lower number indicates the maximum optical resolution of the scanner in either direction (probably horizontal, or parallel with the light), as you mentioned, and you are right that this is the highest res at which you can scan without interpolation.

Think of the numbers as indicating the scanner's capability, rather than a resolution you would use. A scanned image must be uniform in resolution, otherwise it is obviously distorted. 600x600 means that the scanner has 600 CCD pixels per inch across, and the motor driving the CCD arm can step in increments of 1/600 inch. I hope that makes sense.

Maybe an example will help.... the Epson 2450 lists at 2400x4800dpi. What this means is that there are only 2400 CCD pixels per inch across, but the drive motor can make steps teeny enough to actually scan 4800 dpi vertically. In theory this means that scanning at 4800dpi will only be interpolated in the X dimension, and the Y is determined optically. In practice, however, it doesn't really make much difference---interpolation is interpolation, though some scanners interpolate better than others.

Good reading: http://www.scantips.com

Good luck, and I hope I haven't confused you even more
Jefro


top of page To top of page
Which scanner should I buy?
filmscanner
Melvyn Kopstein wrote in message March 29 2001 16:27
I am hoping to gain insight to help with a scanner purchase(s). The whole matter of scanner resolution is extremely confusing and makes a reasoned buying decision difficult. I am an amateur who shoots with a Canon Elan 7e and assorted lenses. I want to be able to scan negatives and prints (4 by 6 generated by standard commercial/widely used labs). I am considering buying an Epson 1650 photo. It has 1600 dpi resolution (3200 is the upper non-optical number) and a negative/slide adapter. An about to be released.......
As with prints, I'd like to modify/improve the result in the "digital darkroom." Should I get a dedicated film scanner for this, or would either of the aforementioned Epsons work? I was considering the Nikion Coolscan IV (2700 dpi). Any help would be greatly appreciated.

Leonard Evens answered October 3
I see you are getting the usual contradictory advice. But I've been through this recently so I think I can help you.
"I am hoping to gain insight to help with a scanner purchase(s). The whole matter of scanner resolution is extremely confusing and makes a reasoned buying decision difficult. I am an amateur who shoots with a Canon Elan 7e and assorted lenses. I want to be able to scan negatives and prints (4 by 6 generated by standard commercial/widely used labs)."

Are you just doing 35 mm or are you considering doing medium format? It makes a big difference.

"I am considering buying an Epson 1650 photo. It has 1600 dpi resolution (3200 is the upper non-optical number) and a negative/slide adapter. "
It comes with a built in adapter for 35 mm. You can buy an addon transparency unit which in principle will handle up to 4 x 5. I have the 1640 Photo which comes with the transparency adapter, and I use it primarily for medium format.

"An about to be released Epson (2450 photo) will offer 2400/4800 resolution, USB2, and more convenient means for scanning negatives and slides. My goal in scanning prints will be to crop and to adjust for brightness, redeye, etc. using Photoshop Elements. I will probably prints the revised file to make prints no larger than 8 by 10. How much scanning resolution do I need if I plan to crop and modify the file generated by the scanned print?"
If you are going to scan prints and then enlarge by a factor of two, you may want to scan at 600 ppi. Either of the scanners you are discussing is more than adequate for that purpose. Usually prints are printed at 200-400 ppi, which is considered adequate for a high quality inkjet printer. You can experiment to see what you like. Every time you enlarge, you should multiply by the magnifications factor to get the target resolution you want for printing. So if you enlarge 4 times, and want to print at 300 ppp, scan at 1200 ppi. (But see below.)
But don't expect very high quality results from scanning prints if you enlarge significantly. The print won't have enough detail for that. To get better quality, you will have to scan the negative or transparency instead.

" Does the commercial lab's 4 by 6 print have a resolution of ~ 300 dpi? If that is the case, then what good would it do to scan at higher than this? "
I'm not sure, but I believe a commercial print does have more detail than that, but generally you are right. See Wayne Fulton's scanning tips web page for specific recommendations: www.scantips.com It is an excellent starting point for all questions about scanning, and he has additional links if you want to go deeper.

".... I also want to scan 35 mm negatives - new ones as well as older ones. As with prints, I'd like to modify/improve the result in the "digital darkroom." Should I get a dedicated film scanner for this, or would either of the aforementioned Epsons work? "
That depends on how demanding you want to be. A dedicated film scanner will generally do better, but it depends on the film scanner. I have an HP Photosmart S20 which in prinicple scans at 2400 ppi. As best I can tell, it won't do much better, if at all, then the flatbed Epson 1640 on 35mm film at 1600 ppi. But better films scanners, selling for $800 or more will probably do significantly better. However, I have produced 8 x 10 prints using the Epson at 1600 ppi from 35 mm negatives which many people would consider acceptable. (But I don't.)

"I was considering the Nikion Coolscan IV (2700 dpi). Any help would be greatly appreciated."
That is considered a pretty good film scanner for the price.

One last point. Don't confuse scanner "resolution" with resolution in the ordinary sense of the word as used in photography. What it is is the sampling frequency. It tells you how many samples are taken per inch. The actual resolution, in terms of ability to distinguish fine detail is going to be at most half that and usually even less. Factors like the optics and how the sensors are designed will also play an important role. That is why the Nikon at 2700 ppi is much better than the HP S20 at 2400 ppi.
-- Leonard Evens len@math.northwestern.edu Dept. of Mathematics, Northwestern Univ., Evanston, IL 60208


Top of page

This page was updated March 17 Year 2003

back home