I wonder how the new Canon 53mp 5D would do instead of a Phase One back???
I wonder how the new Canon 53mp 5D would do instead of a Phase One back???
When it comes to scanning with a camera sensor, dynamic range and freedom from noise are more important than the resolution characteristics of the system. According to DxO, Nikon has the edge over Canon in those regards. If you're willing to stitch, then you can increase the amount of detail captured by upping the magnification. It's also likely that a system designed around a lens optimized for one magnification will perform better than one designed for a wide range of magnifications.
“You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
― Alexander Den Heijer, Nothing You Don't Already Know
I wonder if hasselblad will get pissed that they used something that looks awfully similar to the Imaon film holders....
Hi Jim!Originally Posted by Jim Andrada
I'm the product manager for the DTDCH Film Scanning Solution. Since your post we've been busy updating and adding more information and doing test comparisons to drum scanners.
The last video on this page (one hour webinar):
http://dtdch.com/page/media#workflow
The videos on the main product page:
http://dtdch.com/page/film-scanning-kit
The pricing is definitely not competitive with a flatbed, and for individual photographers who are currently scanning a few dozen images a week at home with a flatbed, this solution is not a suitable replacement. It's primarily targeted around service bureaus, libraries, archives, and other institutions that have projects to scan thousands or even millions of images. It might also make sense to a very small number of individual photographers that currently use (or are about to buy) a high end drum scanner, especially those who own (or are about to buy) a digital back, as that is a major driver in the total price.
I'll reply to a few of the other questions posted here, and I'm glad to answer any additional questions on this forum or by email (dep@digitaltransitions.com or info@doug-peterson.com depending on if the topic is my professional or personal work).
We definitely looked into the current carriers on the market before deciding to manufacture our own in the USA. Imacons are excellent (both in use and quality of construction) but are targeted at a system where the carrier must bend in an arc. When in that arc shape it holds quite flat, but when laying flat (as it would in our case) it does not hold its shape (I'm not dumping on them here, again, they were not designed to be used flat). We also looked at the Epson and third party carriers but they were all made of plastic and our target market for this device is measuring quantity in hundreds of thousands of images (our shutter for instance is warrantied for one million captures), and we were afraid anything plastic would wear/bend/break during the course. Moreover for the higher end work with this system plastic is hard to keep in the tight tolerances required to compete and exceed the resolving power of a drum scanner.
Our system's primary capture method is a single shot.
We also support stitching (see the workflow video linked to a few posts above) which is important on larger format film like 4x5, 5x7, and 8x10 film if you want more than 80mp (aka 10k horizontal resolution, aka 480mb file) worth of resolution.
Our solution was inspired by the surprising number of our clients that were doing some form of dSLR or digital back scanning using ad-hoc or DIY holders/lighting. It is meant to address the short comings of the solutions we saw:
- the need for built in light gating which saves considerable per-image time compared to
- the option for no-touch carriers for those institutions that don't want anything to come in contact with the emulsion (to reduce wear/tear on the materials being scanned)
- elevation of the film away from the light source to reduce heat that might curl the film or damage particular historical emulsions
- tight control of all dimensional tolerances to ensure extremely tight planarity between the sensor, lens, and film (not too important for low res scans like 500ppi, pretty important at 1000ppi, very important at 2000ppi, absolutely essential at high-end scan res like 5000ppi)
- the separation of the carrier from the mounting point so that teams of two can more efficiently use the system (one person loads/unloads, the second person scans and QCs the work)
- elimination of vibration from mirror or focal plane shutter (not consequential for low-res scanning, make-or-break for high-res scanning)
- elimination of focus drift present and focus-postition-detent-formation when using general purpose lenses in a vertical orientation for extended times)
- better lens quality (again, more important the higher the res you want to attain)
- better software integration (the C1 CH software which includes negative inversion, good auto-levels tools, focus meter in live view for establishing focus by algorithm)
- greater physical durability
It's really not accurate to call it a scanner. But for SEO reasons we need to use the word scanning and film in close proximity. In person I refer to this as a transmissive material digitization system (because it is not just for film, and it is not a scanner).
I'd invite you to keep an open mind about the infallibility or insurmountability of the image quality provided by drum scanners. We've been running tests for the last two months. I see you're in New York. Our office in mid town has this system set up most days, and we'd be very glad to set up an appointment for you to bring us some of your film that you have previously drum scanned so we can show you the results with our system. I can also email you links to a few gb worth of tests, but then there will always be the question in your mind of whether the drum scan was done as well as could be, or whether the drum scanner was out of calibration, etc etc - so we'd really prefer to have you run your own test with us.
Fortunately most of our target market has a "trust but verify" mentality. The advent of objective measurements of image quality when doing reproduction photography (e.g. http://www.dtdch.com/page/fadgi-imag...ormance-report) has gone a long way to eliminating marketing fluff.It's a neat looking system, although the Capture One Cultural Heritage software alone is $6000. I wonder if they have people telling them that since they're not using a line sensor, that it isn't worth doing? I know some people who like saying that sort of thing.
We'd be glad for you to run the test using our system. However, in general the limitations/challenges would be:
- Vibration from the focal plane shutter. I believe (can anyone confirm) that you can eliminate the first curtain when capturing from live view but cannot eliminate the second curtain which is still physical even when capturing from live view. You might also be able to mitagate this somewhat by using strobe with short flash duration instead of continuous light (our stage comes with longer legs you can swap in for just that reason). But the numbers can be quite staggering at high resolutions. If scanning at 5000 ppi for instance the feature size you are capturing is 5 microns across, so if you want 93% sampling efficiency you'd need to reduce vibration during the exposure to that which causes less than a third of a micron movement of the film vs the sensor.
- Color. We provide bespoke color profiles for each of our digital-back:lighting configurations, but do not provide this for the variety of dSLRs out there. This could be overcome by the customer doing a careful creation of a good custom profile, but our experience is this is more time consuming and error prone than generally expected, even if you're quite careful and methodical about it.
- Lenses. Canon does have a good high-magnification macro lens, but you'd need to test how it behaves when mounted vertically. Typically the nylon rings used in the focusing mechanisms exhibit micro-slip when mounted vertically for extended periods and have the tendency to develop moderate detents if used at the same focus setting vertically (e.g. for a particular PPI) over an extended time. There may be appropriate lenses for this for Canon, but it falls outside my area of expertise. The lens we use is the Schneider 120mm ASPH but the Canon 5DsR has a smaller pixel size than our 80mp back (since 53mp are placed onto a considerably smaller sensor) so diffraction would kick in earlier and we are already often using the lens near wide open. We'd have to test what limitations on absolute resolution that pair would be prone to.
- Dynamic Range. Some transmissive materials like color negatives do not have a lot of physical dynamic range (the range of the scene they were capable of capturing was wide, but the density range [DMin to DMax] this was translated into on the physical film was quite narrow). Other materials like B+W negatives and glass plate negatives have very high physical dynamic range. Using a digital back allows the capture of all materials we've tested, in a single shot, and to capture large sets of images without adjusting the capture exposure (as the dynamic range of the back can accommodate both under and overexposed negatives). You may be able to overcome this limitation by bracketing, but you'd need to evaluate whether the film can be kept in registration (within a fraction of a micron) between exposures. For material like color negatives this should not be a problem.
- Mount accuracy. Our camera uses a large steel pin rather than a threaded adapter. Given the need to set and then keep the camera within a fraction of a fraction of a degree of tolerances (depending on how high resolution you want to scan at) this could create a hassle factor. I'm sure it could still be set to the required tolerance, but it would not be as easy or elegant to do.
Depending on the resolution you need to capture, the dynamic range of the physical materials you are shooting, and the volume you'd be doing it could be a viable solution. Every component of our system is available as a modular component, so if all you wanted was the carriers, or stage, or bench, we're glad to help.
It seems from a conservation standpoint this system provides far more safety to the original.
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