Imacon 848 technique

[archivue]

Is it safe to scan a 4x5 negative at full resolution (2040) and in the raw mode 3F, then converting it in tiff later on an other computer using flexcolor... or shall i make all adjustments before scanning and saving it directly as a 16 bits tiff?


PS : in the 3f mode, shall i use sharpening or not ?


Thanks.

[nelson_chan]

Archivue,

I rent an Imacon per hour and use 3f raw scanning exsclusively. I then adjust at home on my personal computer which has Flexcolor on it. This is great for scanning as many negs as possible without really breaking the bank. I also do not use sharpening when I scan (though when you do a 3f, sharpening is not applied). Only when you process the 3f into a tiff, is when you determine whether you want to sharpen or not in the settings for processing. I prefer to use PhotoKit Sharpener.

The main reason for using a 3f in my opinion is to make corection composites out of your negs to reduce the levels of noise and artifacts. I'm only talking about compositing for color or exposure. Not anything like Gursky or Crewdson (don't get me wrong, I like their work), but you could potentially do that. This technique of compositing gives you a much cleaner file for a final result of an exhibition quality print.

I hope this helps.

[Stephen Best]

Is it safe to scan a 4x5 negative at full resolution (2040) and in the raw mode 3F, then converting it in tiff later on an other computer using flexcolor... or shall i make all adjustments before scanning and saving it directly as a 16 bits tiff?


PS : in the 3f mode, shall i use sharpening or not ?


Thanks.

I normally do an unclipped, unsharpened scan and work on this ... but I always have the option of rescanning. If you don't, the 3F workflow is probably a good idea. Did you know that you can install the 3F plug-in and open the scan directly in Photoshop? Just assign the scanner profile (Flextight 646 & 848 v2.icc or Flextight X1 848 & 646.icc) and convert to your working space. The image will be pretty flat.

[Kirk Gittings]

I have never used the 3f raw option, as I am not pressed for time when working on the scanner. Is it a true proprietary RAW file format? What is it?

[nelson_chan]

The 3f file for Imacon is its own RAW format. Essentially, the scanner will scan the true resolution of the neg. No information is clipped, adjusted, or interpolated. It's mainly meant for archiving. Think of having access to a digital archive of your negatives. It's a glorious feeling to know that you can go back to the 3f file of xyz-neg and work on it when ever you want.

I however do not work with an archive. I just scan what I need to when I need to. I work on images very singularly. The beginning of my work flow starts with processing a neg over and over again. I will composite a neg by isolating the processing for highlights, shadows, and color. Compositing an image this way creates for a much cleaner file. Because my end result is always an exhibition quality print (whether inkjet or digital C) this work flow keeps noise and artifacts to an extreme minimum. Even if I owned an Imacon scanner, I would always do this so as to have a pristine file. I hope this helps. Feel free to check out my website- almost all of the images were composited this way.

[vijaylff]

I rent time on an Imacon as well, and have never considered using the 3f format, but as Nelson points out, it could be useful for getting the most out of a negative by processing differently for highlights and shadows. Is the Flexcolor software freely available to those who don't actually own the scanner?

thanks,
Vijay

[Ted Harris]

Like Kirk, I have never used the 3f format and I have one question .... does that format maintain the "hidden" scanning that is so troublesome with Imacon's software? One of the reasons Imacon scans frequently appear so good is that the zero setting for sharpening is actually not zero and you have to set it at ~ -160 to actually eliminate sharpening. If you know what you are looking for you can easily see the sharpening artifcats.

[Stephen Best]

Like Kirk, I have never used the 3f format and I have one question .... does that format maintain the "hidden" scanning that is so troublesome with Imacon's software? One of the reasons Imacon scans frequently appear so good is that the zero setting for sharpening is actually not zero and you have to set it at ~ -160 to actually eliminate sharpening. If you know what you are looking for you can easily see the sharpening artifcats.

The 3F file is just a sensor dump. The file itself is a TIFF variant with extra tags to support FlexColor settings. If you don't want sharpening, turn it off (the setting is Apply Unsharp Mask, Amount -120) or open the 3F file directly with the plug-in.

[Walter Foscari]

The Imacon I rent time on runs on a MAC. I have the latest release of Flexcolor running on a PC. If I save the scan as a 3F file will I be able to open it on my PC? In other words are 3F files portable across platforms the same way that TIFFs are?

[Stephen Best]

The Imacon I rent time on runs on a MAC. I have the latest release of Flexcolor running on a PC. If I save the scan as a 3F file will I be able to open it on my PC? In other words are 3F files portable across platforms the same way that TIFFs are?

You should be able to (but I don't have a PC and haven't tried it myself).

[nelson_chan]

In regards to the sharpening:
As far as I knew, if you unchecked the two "Apply" boxes in the Texture setting in Flexcolor, then saved it, none of the sharpening would be applied when you choose that particular profile with processing into a tiff. Please let me know if that is not true.

[Baxter Bradford]

The sharpening topic in FFF and TIFF files has just been discussed again by the imacon user group at yahoogroups.com. There is some excellent advice in their archives - especially by Gerry Yaeger who is/was a trainer for Imacon. His posts are full and informative.

Suggest joining (it's free) and seeking the answers there - far better than I can type! Flexcolor is a powerful program and the manual isn't always too helpful....

Essentially I've found something which works for me, so I just use this. I am not too interested in the semantics, just getting best results.

I think that OP could get max throughput using FFF scans, then process at elsewhere when not so time constrained.

[Walter Foscari]

The Imacon I rent time on runs on a MAC. I have the latest release of Flexcolor running on a PC. If I save the scan as a 3F file will I be able to open it on my PC? In other words are 3F files portable across platforms the same way that TIFFs are?

- Answering my own question here - Forwarded this issue to Imacon tech support and they confirmed that yes, 3F files are portable across platforms (which makes sense really since they appear to be Tiffs in disguise)

[nelson_chan]

great to hear walter. hope your scanning goes well.

[Kirk Gittings]

A naive thought maybe? Another question about 3F raw files. Is there a native resolution built into them as DSLR Camera Raw files are? For instance, a raw file from a Canon 5D is 12.7mp which translates to a native file size. Output above that size is interpolation with clearly degraded images. Would this not be true of 3F files too since a scanner is really only a big digital camera?

[nelson_chan]

Kirk,

Yes, a 3F file is a scan at true resolution with a neg. A 4x5 true resolution scan on an Imacon 949 is 2040 spi.

[Stephen Best]

A naive thought maybe? Another question about 3F raw files. Is there a native resolution built into them as DSLR Camera Raw files are? For instance, a raw file from a Canon 5D is 12.7mp which translates to a native file size. Output above that size is interpolation with clearly degraded images. Would this not be true of 3F files too since a scanner is really only a big digital camera?

Flextight scanners use a trilinear array and aren't Bayer-interpolated like typical digicam files (thankfully). The 3F files are 16-bit per channel. On the higher end models (those with Active Cooling) all 16-bits are used. Normally you set it to scan at maximum optical resolution for the original holder in use.

More info in the "Introduction to the 3f Format and Workflow" section in the FlexColor Scanner manual:

http://www.hasselblad.com/media/139772/flexcolor_scanner_uk.pdf

[joolsb]

Is it possible to get hold of a copy of FlexColor without buying a scanner? If so, how much does it cost?

[Kirk Gittings]

I haven't tried this workflow yet and won't till I get back to Chicago, but I consider that it has great potential.

[Stephen Best]

Is it possible to get hold of a copy of FlexColor without buying a scanner? If so, how much does it cost?

It's available for free download by registered owners of Flextight scanners. Speak to the person who owns the scanner you'll be using.

[Kirk Gittings]

I haven't tried this workflow yet, and won't till I get back to Chicago where we have two Flextight X5's, but I consider this to be an excellent potential workflow.

[Stephen Best]

I haven't tried this workflow yet, and won't till I get back to Chicago where we have two Flextight X5's, but I consider this to be an excellent potential workflow.

I'm not sure it offers any advantages over the 3F plug-in workflow I outlined above. In many respects, scanner software (another than to initiate the physical scan) is an anachronism. It's working on exactly the same 16-bit data as available to Photoshop.

[joolsb]

Just to be clear on this, if I open a 3F file in PS then this will essentially be the basic scanner output with no settings applied, won't it? Or does PS recognise the special tags in the 3F file and apply some processing of its own?

I've just tried comparing a 3F scan from an X5 with its associated TIFF in PS at 300% and there seemed to be some evidence of sharpening in the 3F but not nearly as strong as in the TIFF.

Can anyone shed any light on this?

[Kirk Gittings]

I'm not sure it offers any advantages over the 3F plug-in workflow I outlined above. In many respects, scanner software (another than to initiate the physical scan) is an anachronism. It's working on exactly the same 16-bit data as available to Photoshop.

Isn't that what we are talking about?

On the second part of you statement, There is more than a fair bit of debate about that. Certainly an 8 bit workflow shows tremendous advantages to using the scanner software for major adjustments, whether this is meaningfull in a 16 bit workflow is debated. I think it is on scans that have a fair amount of noise ie prosumer flatbeds, making major adjustments in the scanner in 16 bit translates to less noise enhancement compared to the same adjustments in PS.

[Stephen Best]

Isn't that what we are talking about?

There's two ways to handle the previously captured 3F file:

1. Open the 3F file in FlexColor then proceed as you would with a normal scan (set black/white point etc). When you save the file, these settings will be applied and the result opened in Photoshop (if you've set it up to do so).

2. Open the 3F file directly in Photoshop with the 3F plug-in. No settings will be applied.

[Stephen Best]

I've just tried comparing a 3F scan from an X5 with its associated TIFF in PS at 300% and there seemed to be some evidence of sharpening in the 3F but not nearly as strong as in the TIFF.

I'll have to do more testing but it would appear that there's a difference in the application of sharpening settings if you're doing a normal scan or opening the 3F file in FlexColor then saving it.

[Darren Kruger]

There's two ways to handle the previously captured 3F file:

2. Open the 3F file directly in Photoshop with the 3F plug-in. No settings will be applied.

Do you where to get this plugin and if it is available to people who don't own an Imacon? School has one I can use but I would like to use the scanned 3f files at home. I can open the 3f files I have as tiffs, but an looking to see I can get better results by using an official Imacon program/converter.

-Darren

[thompsonkirk]

Excuse me for bringing such an old thread back to life, but I have a question:

I can rent time on an 848 & want to use the 3f technique.

My previous workflow has been to save 16-bit scans as .tifs & open them in LR/ACR. Can I continue to do this with 3f scans, or do I have to convert via FlexColor to 8-bit .tifs?

Since I don't have a FlexColor license, apparently I'd have to use the rental studio's FlexColor plug-in to convert to .tif. But could I keep the original 16-bit 'raw' scan to convert in LR/ACR, or would FlexColor necessarily change the .tiffs to 8-bit?

Kirk

(PS on why I want to stay in 16-bit if I can: I use a wide-format Canon printer that will send 16-bit 600 ppi files to the printer via PS plug-in, bypassing the printer driver. I've invested in the memory it takes, & the necessary patience, to work with this size of file.)

[Kirk Gittings]

As it turns out there is nothing special about 3f files. Hassy was going to develop it as a raw format but never did. It is just a tiff even if it says .fff. You can simply edit the file name and change it to .tiff and it makes absolutely no difference. Save it in 16 bit and work on it in 16 bit.

[thompsonkirk]

Hi Kirk,

I gave it a try, but didn't get the results I expected! If I set the film type as color negative for Portra & re-tag the .fff's as .tiffs, they open as negatives.

Perhaps this is what's supposed to happen – as might be desired by folks who like to scan negatives as postives? (I remember learning this technique from Ian Lyons' Computer Darkroom site about 10 yeas ago.)

Kirk T.