Imacon 949 versus drum scan

[darcy_cote]

Has anyone seen a comparison of a Imacon 949 scan and a drum scan. I want to know how

close the detail in the shadows are.

 

Darcy

[andrew_hull]

Correct me please, if I am wrong, but isn't the Imacon 959 a drum scanner?

[darcy_cote]

The Imacons are not drum scanners.

[bruce watson]

It's going to depend on what type film you are scanning, and what enlargement level you intend to scan to. Negative films should do fine. Trannys are going to be what the Imacon chokes on. It's really not an Imacon vs. Drum scanner question - it's a CCD vs. PMT question. Getting PMT performance from a CCD is the "holy grail" for the CCD makers. And, we aren't there, yet.

 

The other thing is, you can't fluid mount on an Imacon. Therefore, your scans are going to require more spotting time in your image editor.

 

As to sharpness, the Imacon can probably, for most films, do well up to the 6-8x enlargement range. PMT scanners will be performing better above that.

 

So, for big enlargements of trannys, PMT scanners will give you better performance. For smaller enlargements of negatives, the CCD scanners go quite well.

[darcy_cote]

I am primarily interested in the scanning of 6x17 trannies and the shadow detail in them.

[doug_meek1]

Let me preface this post by saying that I am not much of an expert on scanners, or anything else for that matter that has anything to do with computers. Hogarth mentions PMT in his post above - I don't even know what that stands for! That gives you an idea of my lack of computer-savvy. I recently had a 4x5 chrome scanned by 2 different top-notch labs. One was scanned on an Imacon, the other on a Tango drum scanner. I then had 16x20 prints made of both on the same printer - a Fuji Chromira (16 x 20). Both prints look excellent in every respect except for one dramatic (and I mean dramatic) difference - shadow detail. The print which originated with a Tango drum scan was FAR superior in rendering shadow detail to the print which originated with an Imacon scan. This comparison cost me a fair amount of money since I had to pay twice to have the same print done, but for me it was worth it. Going forward, I won't use a lab that used an Imacon. I understand that there can be many variables involved (such as the skill of the operator) which may seem to invalidate this comparison, but all of my research would seem to indicate that both labs have very skilled people operating their scanners. Again, I admit to knowing very little about scanners, but I do know how to compare prints. I hope this helps.

[andrew_hull]

Darcy,

 

Apologies, I always thought they were...

 

Andrew

[bruce watson]

<i>I am primarily interested in the scanning of 6x17 trannies and the shadow detail in them.</i>

<p>

In that case, you might well want to have them drum scanned. The last independent test I saw (here: http://www.scannerforum.com/ but you'll have to dig around for it in the "DIMA 2002 scanner roundup" presentation, about page 21 or later) indicated that the Dmax for an older Imacon was less that 3.0, where as most drum scanners could do 3.4+ While I'm sure that the Imacon's have improved since that test, I'm also sure that CCDs haven't equaled PMTs yet.

<p>

In otherwords, if your game is shadow detail in trannies, drum scanners are the way to go. Of course, YMMV, but I don't think it will vary that much ;-)

[bruce watson]

Doug,

 

CCD = Charged Coupled Device

 

PMT = Photo-Multiplier Tube

 

These are the underlying technologies for scanners. Flatbeds,Imacons (which aren't flatbeds or drum scanners), and "dedicated film scanners" like the Minolta and Nikon small and medium format film scanners use an array of CCDs and scan the film a full line at a time.

 

Drum scanners use PMTs, and scan the film a single pixel at a time. This is much slower of course, and it requires two axes of motion - you have to spin the film in front of the sensor system so that it can sample all the pixels in a line, one at a time. Then you have to index the film one line width and sample the next line. And so on.

 

They did it this way because PMTs are much larger, and much more expensive, than CCDs. You can make an array of 4000 CCD sensors with lenses for each one, for a lot less than you can make three PMTs.

 

OTOH, PMTs are very sensitive, have a huge dynamic range, and with the drum scanner optics, can be extremely sharp. I often don't bother to sharpen my scans from drum scanners, but I always have to sharpen scans from CCD scanners.

 

But you've done the comparison yourself and seen the results first hand. You know what I'm talking about from a results perspective, yes?

[doug_meek1]

Hogarth -

 

Thanks for the explanation. Sometimes (lots of times) that technical stuff goes way over my head. How I wish I was more "digitally inclined" - my wife picks up on it very easily. Bottom line, however, is that what I see in the prints mirrors exactly what you said by way of explanation. Thanks again and good shooting!

[wayne_davis3]

I know i'm late to this form but do you need anymore info on the Imacon 949 scanner? I have been useing it you a year now. My back ground is prepress and I have beed useing drum scanner for 20 years. Please let me know if I can help.