RESOLUTION FLEXTIGHT 646

[jotloob]

Currently I am working the hybrid way (artix scan 1800) and I plan to buy a FLEXTIGHT 646 as my negatives are 6x6 cm , 6x12 cm and 4x5 inches . I will definately not go for any digital back for my HASSELBLAD V-SYSTEM .
Looking at HASSELBLAD and IMACON homepages , i can only find , a given resolution of 80dpi to 6300dpi .
Now , what does that mean ? ? ?
What is the resolution for 6x6 and 6x12 ? ? ?
What is the resolution for 4x5 inches ? ? ?
I can not find these data anywhere .
Is there a formular , where you can calculate the resolution for any given format . ? ? ? Can anyone please help .

 

[qnu]

Jürgen,

It scans using one resolution (which you can choose between 80 and 6300 dpi), no matter how large the original.

So if you scan a 35 mm frame at 6300 dpi, you get a 6300 dpi scan of a 35 mm frame.
If you scan a 6x6 frame at 6300 dpi, you get a 6300 dpi scan of a 6x6 frame.
Etcetera.

Select a lower resolution, and it scans everything (small, large, or in between) using that lower resolution.

 

[afranklin]

Q.G.,

I am curious. Can the 646 scan 4x5 at 6300ppi? When it does a lower resolution scan, is it simply decimating the 6300 scan, or does it adjust it's imager/lense stage (or film stage) to change the magnification to achieve this lower resolution?

Regards,

Austin

 

[jotloob]

In a dealers catalogue i found the following for the FLEXTIGHT 848 SCANNER : Resolution is 8000dpi for 35mm film,3200dpi-4000dpi for MF , up to 2040 dpi for a 4x5 film and up to 1600dpi for a 13x18 film . All resolutions non interpolated .
So if this is true , the values for the FLEXTIGHT 646 must be different , because if its different max.resolution , which is not 8000dpi but 6300dpi .
So if this is true , i would like to understand , why are there different resolutions . How are they calculated ?
This topic is not covered in any technical information issued by
IMACON or HASSELBLAD .
(At least , i could not find anything about this topic)

 

[afranklin]

> In a dealers catalogue i found the following for the FLEXTIGHT 848 > SCANNER : Resolution is 8000dpi for 35mm film,3200dpi-4000dpi for MF , > up to 2040 dpi for a 4x5 film and up to 1600dpi for a 13x18 film . All

> resolutions non interpolated .

This is how the Leafscan works as well. It changes the magnification (2 :1 for 35mm, 1:1 for medium format and 1:2 for 4x5) to achieve the different resolutions. That is why I asked about how the 646 works. They could have either used a rather wide sensor (I believe 14000 is available and will cover 6cm at 6300, but won't do 4x5...which is why I question if the 646 does 4x5...) or could change the magnification.

Regards,

Austin

 

[jotloob]

The ARTIX SCAN 1800f (which i use) scans all formats at the same resolution which is 1800 dpi .This is due to the design and construction . An output resolution of 360 results in a factor of 5 . 1800:360=5 . That means , any scanned format can be printed at 360 resolution , five times bigger than the original . (If you take an output resolution of 300 , which i will not use ) you get a factor of 6 .
The Dmax. of the 1800f is 4,8 .
So , this scanner is , in deed , a very good scanner for 4x5 inches and larger . For MF you are already a bit limited , because using faktor 5 , you come up with an image of 28x28 cm . A bit lousy , when going for bigger images . (This is , not using any genious sharpeners, or whatever other "blowup software" ) .

The FEXTIGHT SCANNERS seem to have a completely different design (despite of vitual drum) .
I have only figures for the 848 type , which seem to be far better , than for the 646 .
For ex&le : take a 35mm negative , scanned at 8000dpi , you get a factor of 22,22 . Thus , you can produce an output , at 360 , of almost 80cm for the long side of the image . Great , isn't it ? ? ?
If then , you take a 4x5 inch negative , the resolution is only 2040 , which then results in a factor of 5,66 . So the advange of the 848 for larger formats is not all that much . But the price is "outstanding"
The figures for the 646 will even be a bit lower .

So my decision for a 646 is open and i find my ARTIXSCAN 1800f a great scanner (regarding bigger fromats) .

I will contact HASSELBLAD for more details , but as i know HASSELBLAD , you must be happy to get an answer .

 

[qnu]

You got me doubting...

The 646 does scans up to A4-format. But it offers two modes: reflection and transmission.
I do not know which mode uses optical magnification...

Best contact Imacon, yes.

The way I know Hasselblad, you always get an answer.

 

[jotloob]

Q.G.
As I am not really satisfied with the resolution for MF of the ARTIXSCAN 1800f (but very good with larger formats) i am seriously investigating , which other scanner could be the candidat.
That's , why i am so much after technical data .

What i found on the IMACON homepage , is a flash movie of the FLEXTIGHT CONCEPT , where they also show a ZOOM SYSTEM (valid for 646 , 848 ,949 ) . Obviously , a magnification is done .
For which mode , is not explained . But i assume it is for transparent mode , because that would match the other figures i already mentioned .

A phone call with HASSELBLAD GERMANY , then brought more light into this scanner darkness . They could not say , why the figures , i am after , are not published , and finally gave me the following figures , after a long search in their computer .

FLEXTIGHT 646 :
Resolution of 6300 for 35 mm format .
Resolution of 3200-4000 for MF (including 6x12)
Resolution of 2040 for 4x5 inch
Resolution for 5x7 inches I did not ask , but will be like for the 848

So , this would let me assume , that magnification is done for transparent mode . But , it does not state , that magnification is done or not done for reflection made . Unfortunately , and i do not understand why , the technical information , IMACON and HASSELBLAD give in their scanner data sheets , is somewhat incomplete , or , you could also say , lousy .

The FLEXTIGHT 343 does not do any magnification , scans all negatives at the same resolution , which is 3200 . But , and that's great , it also uses the "virtual drum concept" .
So , this guy , could be a candidat for me , and with the money i save , in comparison to a 646 , (keeping my 1800f) i could easily buy an EPSON 4800.

Digital Photography is full of mystery and excitement .
The hybrid way is too .

 

[afranklin]

According to the 646 brochure, it uses qty. 3 (one for each color) 8000 element sensors. This means that in order to do scans larger than the sensor is wide, it has to change magnification, and hence, resolution decreases (or do multiple shifted passes).

If it is 6300SPI (they say PPI, but that is a misuse of the term, you do not scan pixels, the result of scanning/s&ling is pixels...so they are not pixels until they are in the computer, so it s&les at x S&les Per Inch)...anyway...if it has only 8000 sensor elements, the reso lution for 6cm wide, assuming it is using the whole sensor, would be 8000/2.25 or 3555.5. It obvously doesn't use the full sensor's width for 35mm.

So, my guess is it has variable magnification, and can adjust the sensor stage and optical stage to provide the differing magnifications.

The brochure is on the Hasselblad web site. It's really rather incomple te though.

Regards,

Austin

 

[afranklin]

Hi Jürgen,

[But , and that's great , it also uses the "virtual drum concept" .]

Why do you believe this is important? Do you understand what they claim is a "virtual drum", and it really has no (or exceptionally little) relationship to a drum scanner at all. It is mostly marketing puffery.

A drum scanner "curves" the film not to make it flatter, but because the drum spins about it's axis and the film has to mount to that drum. The film holder of the Imacons do not spin, they simply curve the film slightl y and other than that, operate like any other flm holder of any other non drum film scanner. This curving of the film has not been shown, to my knowledge, to improve on the film flatness or improve the scans.

Regards,

Austin