Epson 4990 resolution?

[gregory_logiodice1]

Hi All,

 

I am considering purchasing an Epson 4990 for scanning both MF and

35mm transparencies. At most, I would like to enlarge the 35mm to

8x12 and the MF 645 to 13x17 or so. Most of my photography is

landscape and nature.

 

The big question I have about the 4990 is its actual resolution.

Epson says it will resolve 4800 dpi, but in the various tests on the

web, it is easily bested by film scanners with 4000 dpi. It has

been suggested this is because the 4800 dpi claim is an interpolated

resolution, rather than true optical resolution, which presumably is

significantly lower.

 

While my need to scan both 35mm and 645, along with a limited

budget, leave me few other options, I would still like to know what

the Epsons true resolution is if for no other reason than providing

a clear basis for comparison to film scanners.

 

So is the true optical resolution of the 4990 published anywhere by

Epson? Failing that, what are your educated guesses?

 

Thanks for all replies.

[ilkka_nissila]

My estimate is that the MTF starts to drop after 500 ppi and is nonexistent beyond 1200 ppi.

 

I don't think Epson claims that it has a 4800 ppi resolution, it just records that many pixels per inch. The neighbouring pixels will be virtually identical (this is the case at 2400 ppi also).

 

If you want to scan film, buy a film scanner. The 4990 I have gives approximately the same amount of detail from a 6x7 transparency as the Nikon LS-5000 gives from a 35 mm slide. So you'll be able to make a good 5x7 print from your 645 slide and if you don't go closer than 3 feet to the print, you might get a passable 8x10 print from it. 35 mm - are you kidding?

 

(I know I will get flamed for reporting my experiences, but I'm telling what I see.)

[jtk]

I've seen some very fine 6X7 16X20 from architectural pros with 4990's ..it appeas something's wrong with Ilkka's setup or craft.

 

A 4000ppi Nikon scanner will beat 4990 in a large print, but the 4990 can be quite good from 35mm below 11X14.

 

"Resolution" as applied to scanners usually refers to ppi, an inherently deceptive measurement mostly reflected in file size, not directly related to optical resolution, which we actually see.

 

What we actually see is measured by lpm...lines per mm. Lens resolution is measured in lpm, film is measured in lpm, scanners should be measured that way for the sake of communication.

 

A lot can be accomplished with careful post-scan sharpening, a lot can be lost by excessive post-processing.

[mr._smith]

Gregory,

 

The Epson 4990 is capable of professional results with mf negatives. However, you may not like the tonality with 35mm negatives.

 

As for resolution, the E4990 real resolution is a little over that of its predecessor the E4870 which was said to have something like 1600dpi. The early E3200 had a real resolution of about 1200dpi.

 

For 35mm and prints to 8"x12" I would suggest a used Minolta Scan Dual III which can be had for little money.

 

You may be interested in this Epson 4990 review:

 

http://www.photo-i.co.uk/Reviews/interactive/Epson%204990/Page%201.htm

 

Epson 4870/4990 support group:

http://groups.yahoo.com/group/epson4870/

[steven_clark]

My 4990 can yield decent 8x10 from 35mm with some good sharpening, but my Scan Dual III beats it hands down, even without sharpening.

[ellis_vener_photography]

<I>Epson says it will resolve 4800 dpi, but in the various tests on the web, it is easily

bested by film scanners with 4000 dpi.</I>That is a separate issue, possibly having to do

with film flatness. The real full optical resolution is 4800ppi according to my tests. The

next question is: lets say you scan a 6x4.5cm ( 2.3" x 1.7") at at 4800 ppi that makes for

a very large scan, just over 257mb at 8 bits per channel or 515.5mb at 16 bits per

channel. If you print at 360 dpi you are looking at a 30.667" x 22.667" print. Do you ever

plan to print that large?

 

If you want better performance you'll need t ocontact Doug Fisher and buy one of his

medium format carriers for the 4990. try Doug at filmholder@earthlink.net

 

The 4990 can scan 35mm. But from having tried to use one to scan 35mm slides with one,

I can't recommend it for that purpose.

[ilkka_nissila]

Ellis, please show me a crop of a 4990 scan which shows 4800 ppi resolution. I have the 4990 and Doug's holder, and also the associated glass. It doesn't have to detail, grain in a 4800 ppi unsharpnened crop is good enough for me. If I scan at 4800 ppi on the Epson, all I get is large clusters of pixels with virtually identical values. And a very, very large file with precious little information. Since so many people in this group claim that they don't see globs of pixels with similar values, I'd like to see some evidence. Notice that on an LS-5000 with fine-grained film each pixel is sharply different from the neighbouring ones. That's when happens you have a good scanner able to recover some detail. If someone is able to show me a 4800 ppi scan (unsharpened) where each pixel appears as random as on the Nikon, I'll send my Epson in for service the next day. (I'm not holding my breath).

 

Resolution is by definition the spatial frequency where signal equals noise. Contrast is lowered much earlier than at the resolution limit but it can be recovered by sharpening, though some problems do show up when you do this. The best results are obtained when you don't have to sharpen the image since sharpening by a function which is not ideally tailored to the imaging system distorts the final result.

[beauh44]

I don't know if this'll help any, but here's a shot of a surfer scanned with a 4990, the film is Fuji Velvia 50. I didn't use Doug's film holders - just Epson's. I'll post a 100 percent crop too. Everything worked fine for me and much of what I scanned from 35mm made fine 8X10" prints.<div></div>

[beauh44]

D'oh! Meant to make that smaller.. oh well.. I'll leave it be for bandwidth... Anyhoo, here's the 100 percent crop...<div></div>

[conrad_hoffman]

You might search out my recent comments on the 4490, which is similar though not identical to the 4990. MF negs can be scanned and produce very decent 8x10 prints. Not as good, I'm sure, as a dedicated film scanner. 35mm can be scanned to produce ok looking 4x6 prints, but the resolution of the scanner just isn't up to what's required for good results. I think I measured something like 30-40 lines per mm (check my much earlier post), and a good 35mm neg is considered sharp if it resolves about 60 lines per mm. The problem is obvious. IMO, if you need to scan 35mm and get excellent results, you need a dedicated film scanner. Don't get me wrong, I love my 4490, and it's a great tool for a lot of jobs, but scanning 35mm isn't one of them.

[stwrtertbsratbs5]

I have a 4990, but I haven't done extensive work with it. I hesitate because scanning takes a lot of time. And I don't want to rescan once I spring for a Nikon 9000.

 

The 4990 is pretty good. But I think that some of the web reviewers are wild-eyed optimists!

 

Robert

[mike_r.1]

I think it gives better results than you would expect for the money. I find that a print of a 6x6 scanned on my 4990 has more detail than a 35mm scan on my Minolta 5400 (same film, subject etc; but by no means scientific)

 

You have to apply a considerable amount of sharpening to bring out the detail, but it is indeed there.

 

There is a bit of black art too (as with most other scanners) in terms of positioning of film etc.

 

Just buy one from a store where you may return it if you don't like it.

 

Here's a detail sample of a scan of some E100VS, 6x6, scanned at 3200 DPI.<div></div>

[kelly_flanigan1]

Here I have owned a dozen flatbeds. First a 300 dpi class; then a 600 dpi class. The two most expensive ones cost moe that a new Hassleblad kit; and are only "600" and "1200" dpi rated devices. With a professional scanner long ago; there was no bull dung. Today flatbeds are marketed to amateurs which LOVE big numbers; just like the 5HP vacuums with an 18 awg cord. A decade ago the thought was a top end 1200 dpi 2 to 3 thousand dollar flatbed was somewhere like a drum scan at the old 600 line per inch feed rate. Today low end flatbeds have radically wider real dynamic range; cost a fraction of a Hasselblad kit; and folks complain. These flatbed vary from model to model; serial number to serial number. The best flatbed I have for resolution is one of my Epson 2450's; sharper than the other; sharper than our 3200; sharper than my neighbors 48xx unit. Long ago in print shop seminars the high end flatbed makers said that a flatbed would never go beyond 100 to 1200 dpi in real world resolution. My one Epson 2450 is abit like a drum scan down sampled to say 1200 dpi tp maybe 1600 dpi on good days. <BR><BR>With aflatbed you dont get the entire cigar; and never will. All the marketing claims dont fix a rather crude, non lens focused capture.

[beauh44]

I would agree with Kelly. I think too that digital SLRs have spoiled us. I know this sounds silly but I have a 13X19 inch print of my cat taken with a Canon 10D 6 Mp DSLR that just blows me away how sharp it is. (Interpolatated with Photoshop + USM) Conversely, I've got prints that size from a 1DsMKII that are good but don't have the certain "something" the cat shot does. Go figure. (I used the same lens)

 

Anyway, I think flat-bed scanning is a hit-or-miss affair at times. I've got an old Canon FS4000 film scanner that'll scan 35mm slides and print film at 4000 dpi. I scanned a few of the same slides with the 4990 that I did with the FS4000 and the Epson hung in there. Maybe I got a "good" one - I dunno but some of the 8X10s I made looked a little better from the 4990 to me.

 

It's not a drum scan but it just depends on your expectations. You probably won't get a decent 13X19 inch print scanning 35mm with the Epson. (Most labs won't get it right either btw) But if you shoot MF (or 4X5) film you can make prints that size with no sweat.

[berg_na]

The 4990 resolution won't equal that of a dedicated scanner not because it relies on interpolation -- it does not -- but because of its low cost optics. Still, its performance is nothing short of amazing, considering its price is only a fraction (1/5th) that of the Nikon 9000. It's even been compared against a drum scanner here: <a href="http://clarkvision.com/imagedetail/drum.vs.flatbed-scanners/" target=new>http://clarkvision.com/imagedetail/drum.vs.flatbed-scanners/</a>. <p>In terms of actual resolution, the following chart which is akin to its MTF, shows that it clearly resolves out to 4800 dpi although the contrast now drops to about 30%.<p><center>

<img src="http://clarkvision.com/imagedetail/drum.vs.flatbed-scanners/epson4990-edgeresponse.v1c.gif" width=653>

</center>

[van_camper]

"So you'll be able to make a good 5x7 print from your 645 slide and if you don't go closer than 3 feet to the print, you might get a passable 8x10 print from it. 35 mm - are you kidding?"

 

I agree with John Kelly, there is something wrong with Ilkkas scanner. I hope with what has been said you are convinced to send it in for repair. I am getting some amazing results, definately the Nikon 9000 is better, but then again if I want really big prints or am selling limited editions it seems the drum is the only way to go, better for you and the customer. I am having no problem getting great prints from 6x7/6x9 to 16x20, and bigger with 4x5. To say getting a passable 8x10 print is wrong. My 8x10 prints are very sharp and saturated after sharpening, and far better then any print from my enlarger using top notch Rodenstock apo 90mm lens.

 

I suggest checking out www.normankoren.com.

[brian_ellis16]

"So is the true optical resolution of the 4990 published anywhere by Epson?"

 

Not by Epson as far as I know but tests of various scanner conducted by Ted Harris and Michael Mutmansky, the results of which were published in View Camera magazine a couple issues ago, indicate that it will resolve about 2200 ppi. As others have said, the 4990 isn't recommended for use with 35mm film except for web purposes. I'm not sure about your 645 film. I've gotten pretty good but not spectacular results with 8x10 prints from 6x7 film with the 4990 but 645 is almost as close to 35mm as it is to 6x7. I use my 4990 almost exclusively with 4x5 and 8x10 film and does an excellent job there.

 

While the specs of a scanner are important it's at least equally important to spend a lot of time learning how to use whatever software you plan to use. Some people seem to think they should be able to just hit the "scan" button and get excellent results every time. They can't. Scanning is like anything else in photography, it takes some time and effort to learn how to use the tools.

[kelly_flanigan1]

With a smaller 35mm, "MTF like" tests tend to be better or equal than MF or 4x5 with my zoo of Epson flatbeds. The scan is quicker, the film is held somewhat more rigid, there is less scooting due to heat buildup.

[gregory_logiodice1]

Thank you, all, for your thoughtful, detailed, and constructive replies. This has been extremely helpful.

[helenbach]

just a small point (literally): reading through the replies I wonder if there is a bit of mix-up when comparing scanner resolution and lens resolution. Lens (and film) resolution is normally quoted in lppmm - line PAIRS per mm - not lines per millimetre. 60 lppmm needs 120 pixels per mm to match it, in theory.

 

Best,

Helen

[kelly_flanigan1]

Helen; all the optical tests I have done use line pairs per mm. In engineering tests one is reading the "line pair" on the 1951 USAF chart. Folks in industry dont do the "marketing thing" and throw a factor or 2 to boost numbers. It is understood that lines per mm is line pairs per mm in optical engineering; just like 14 shoes sold at a shoe store is 14 pairs of shoes; and not called 28 shoes sold to boost/fake sales numbers. Only in the last couple of decades has this factor of two come up; most by the lay public who has never read a USAF chart, and by marketing scum/rats. Most all decent lens tests are in line pairs per mm, and many are labeled lines per mm, since that is what folks call it. One should not assume that lines per mm is wrong, often it is just a a shortened saying for line pairs per mm.

[oleg_novikov]

I find that the realistic maximum resolution of the Epson 4990 is 1200dpi. Beyond that the scanner does not extract any real detail and is ridiculously slow. See my <a href="http://www.olegnovikov.com/technical/epson4990/epson4990.shtml">comprehensive tests</a>.