Update - microtek 1800f vs. epson 4990

[Kirk Gittings]

Does anyone actually know what the optical resolution of the 4990 actually is?

Roger apparently there is no problem with newton rings. I have not seen any with 4x5. You scan on the glass emulsion up. The plane of focus is above the glass.

[Walt Calahan]

Epson 4990

Optical Resolution
4800 dpi

Hardware Resolution
4800 x 9600 dpi maximum with Micro Step Drive technology

Interpolated Resolution
12,800 x 12,800 dpi

Color Depth
48-Bit RGB (internal & external)
16-Bit Grayscale (internal & external)

Dynamic Range
4.0 Dmax

[Ted Harris]

The real optical resolution of the 4990 is in the range of 1800 - 2000 at best. The manufacturer's claims (as well as those for the Canon 9950 and the MT i800) are pure theoretical limits stated for marketing purposes. Epson comes up with this number as a result of having tow smallish 2400 spi sensor arrays stacked one on top of the other ... same with the others. Dmax is also a theoretical number achieved only in an absolute situationthat bears no resemblance to real photography. The actual Dmax of the 4990 is in the range of 2.0 - 2.2. The numbers published in the View Camera article in the May-June issue for the 4870 will be a close approximation of those for the 4990 as the sensors and mechanics are very similar (perhaps even identical).

[j.e.simmons]

My impression is that Clyde Butcher was shooting 8x10 for the exhibit that I saw. The point about negative size is a good one.

John, I'm in Jacksonville. Email if you're coming this way.

juan

[Kirk Gittings]

"If he is using 8x10 to start, the 20x24 is only about a 2.5X enlargement, and well within the capabilities of the scanner."

Michael you must be working with some formula that takes the scanner's optical resolution, the negative size and the quality of the sensor and projects a maximum size for acceptable resolution. is this true?. Is there such a formula or you are making a judgement call based on experience?

[Kirk Gittings]

Walter,

I love this scanner, the 4990, I use it daily. It is capable, with very careful work to produce exhibition quality work up to 11x14. It is a truely amazing piece of technology for the price, but if those claims were correct it would be a miracle at that price. As Ted said:

"The real optical resolution of the 4990 is in the range of 1800 - 2000 at best. The manufacturer's claims (as well as those for the Canon 9950 and the MT i800) are pure theoretical limits stated for marketing purposes."

[Roger Richards]

Thanks, Kirk. This has been a very informative thread. I have been using an Epson 4870 for small prints from 4x5 and 6x7, with half decent results, but now I need a scanner to make 8x10 color prints up to about 20x24. The Microtek seems to fit the bill.

[Michael Mutmansky]

Kirk,

Based on experience. This equates to only a 10x12 from a 4x5, and as you have said above, the consumer scanners can do that well with care.

I somewhat misspoke when I said 'well within' up above, because regardless of the reproduction ratio, a sloppy scan will result in a poor result, so I didn't want to imply that this type of scan is a casual endeavour that can be done without careful attention.

---Michael

[Richard Martel]

From a personal conversation with Clyde Butcher he is using Epson Ultrachrome ink for his inkjet prints. I can not recall the RIP he is using but I think it was Colorbyte.

[Kirk Gittings]

"Thanks, Kirk. This has been a very informative thread. I have been using an Epson 4870 for small prints from 4x5 and 6x7, with half decent results, but now I need a scanner to make 8x10 color prints up to about 20x24. The Microtek seems to fit the bill."

Just to be clear. Almost all my testing has been done on B&W negs. and my recomendations really are limited to that. I would inquire with Ted Harris about color/sizes etc. related to the 1800F.