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RESOLUTION FLEXTIGHT 646

jotloob

jotloob

Well-Known Member
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 .
 
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.
 
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
 
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)
uhoh.gif
 
> 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
 
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 .
 
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.
 
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 .
 
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
 
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
 
Hi Austin

Did you have a look to the FLEXTIGHT CONCEPT FLASH MOVIE i mentioned earlier in this thread ? ? That convinces me that far , that i believe , the part of the film , which is scanned at a time , is flat , at least much flatter , than using a flat-bed scanner , like my ARTIXSCAN 1800f .
With the 1800f your negatives , using the appropriate holders , will never be really "flat" , but as flat as possible for this design and for the format you scan . The smaller negatives you scan the better the flatness you achive , but never a 100% , because of the tension in the film itself .
So every scanner (flat-bed scanners , virtual drum scanners or real drum scanners) has its advantage and also disadvantage , looking at design , resolution and price .
 
Hi Jürgen,

> Did you have a look to the FLEXTIGHT CONCEPT FLASH MOVIE i mentioned > earlier in this thread ?

No, I didn't.

> That convinces me that far , that i believe > , the part of the film , which is scanned at a time , is flat , at > least much flatter , than using a flat-bed scanner , like my ARTIXSCAN > 1800f . With the 1800f your negatives , using the appropriate > holders , will > never be really "flat"

Well, given I've been scanning film for over a decade (and design design digital imaging equipment, including film scanners), and I've never had an issue with film flatness with my scans (on a Leafscan 45 which uses Beseler 45 type holders), nor has anyone I've heard anyway using say, a Beseler 45 enlarger, complained about film flatness...I'm going to believe it's not an issue in %99.99 of the time for anything up to 6cm wide film. I don't disagree that for 4x5 it *may* be an issue...and that is where a glass holder mitigates this issue.

There is a depth of field issue with the Nikon scanners that use LED light sources...but again, I think that though the film *may* be flatter, that is not an issue...at least it hasn't ever been an issue for me. I believe the Imacon scanners use a cold cathode light source, so DOF should not be a problem.

As I mentioned, until I see a properly done test that shows not only the testing procedure but ALL the data etc., I'll stand by my assertion that this "virtual drum" thing is mostly marketing puffery.

Regards,

Austin
 
Hi Austin,
Long time no see. How are things?
I just wondered what you think of the Nikon LS 9000 ED scanner. I have been thinking about it but it would be a huge investment for me and I want to be sure that it is pretty good before I jump.
I already have a Minolta Dimage Scan Elite 5400 which is very good but very slow with ICE and only 35mm whereas I like 6x6.
Cheers,
John
 
Hi John,

Thank you for asking, things are well...three children later ;-) I hope things are well with you.

> I just wondered what you think of the Nikon LS 9000 ED scanner.

Unfortunately, I have no opinion on most new scanners. But, as I mentioned, the Nikon scanners that use LEDs as a light source have had depth of field/focusing problems in the past. Personally, if I was look ing for a MF scanner, I'd take a good look at the Polariod 120 film scanner an d especially the Microtek version the Polaroid is based on. Sorry, I don' t remember the model numbers.

If you only scan B&W, and are reasonably computer literate, the Leafscan 4 5 is the best B&W film scanner I know of due to it having a separate grayscale channel, which no other film scanners (that I am aware of) have. It does 6cm at 2540SPI, 4x5 at 1200 and 35mm at 5080, which can make some nice size prints. They go for well under $1000 these days. There is a Yahoo group for them as well.

Regards,

Austin
 
> I have a Nikon Coolscan 8000 ( the unit that preceded the 9000) and > have no problem with it. However, I use the glass carrier normally. > I know the arguments for/against glass & glassless carriers with > enlargers (as similar argument holds for scanners), but I have > always found the glass carrier (869G) to be better at holding the > 6x6 film flat, esp 220 film. I also use the additional glass > carrier with various size film masks (869GR) for my XPan quite > successfully. Now that the Coolscan 9000 is out, you may find the > Coolscan 8000s fairly reasonable on the second hand market. The > only real difference between them is a few software features that > you can already find it Photoshop.
 
> Here is a B&H link showigng prices

http://www.bhphotovideo.com/bnh/controller/home? ci=1&sb=ps&pn=1&sq=desc&InitialSearch=yes&O=RootPage.jsp&A=search&Q=*&bh s=t&shs=coolscan+8000&image.x=0&image.y=0

The glass carriers are around $300-350. The "glassless" around $100.

Here is an interesting carrier I had "heard about" a year or two ago ( from the B&H link) ,

Cachet Image Mechanics Fluid Mount Tray for Nikon Super Coolscan 8000 & 9000 ED Scanners

and someone finally made it. A carrier where you can imbed the negative in a fluid layer before scanning. Certain very high end optical microscopes ( oil immersion microscopes--think of something that makes a Hasselblad look cheap) use this technique to eliminate optical aberrations, and achieve extremely flat image fields. A heard someone was trying to make one a couple of years ago for the Coolscan, and it looks like it finally came to fruition.

It runs about $500, but should give "extremely...EXTREMELY " good results.
 
Oil immersion in microscopy is used to increase the numerical aperture, and with it the obtainable resolution beyond what would be possible without oil. Not to get flat image fields.

Fluids in scanning are used to make the film stick to the glass in the carrier, i.e. keep it as flat as the thing it is sticking to.

Two quite separate thingies, so not much point in thinking about microscopes.
wink.gif
 
As a note on glass carriers and fluid mounting for CCD film scanners, ther e is a guy who has a fluid mounting glass carrier for the Leafscan 45. I have not bought one, but perhaps should. It is only $200 or something l ike that. It has been claimed that it reduces the grain significantly.

I doubt anyone will be making a glass carrier for the Imacon, since it is a curved carrier...or if they did, it would be quite fragile and expen sive, as the two pieces can't be identical.

Regards,

Austin
 
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