Designing a new film scanner; need your help

[pyeh]

Nice work, quejai. Hurrah for uni holidays, giving you time to work so hard on this project! Also, clever interpretation of the price survey results, in setting the target cost to buyers of this scanner. Although, I notice that the percentages add up to more than 100%, so I guess people can vote for more than one category.

 

[mani]

Take a look at the Kickstarter from Lab-Box: after just 3 days they're approaching $400,000! (just $3000 short on Feb 26).

Think how enormously popular a well-produced and reasonably-priced scanner would be! There's a massive thirst out there for products that so far haven't been well-covered for this new generation of film-users. Lab-Box proves that if you pitch it right, people are there to back you!

Please consider going into mass-production with this product - I seriously think that (pitched correctly) this could be massive.

 

[quejai]

Take a look at the Kickstarter from Lab-Box: after just 3 days they're approaching $400,000! (just $3000 short on Feb 26).

Think how enormously popular a well-produced and reasonably-priced scanner would be! There's a massive thirst out there for products that so far haven't been well-covered for this new generation of film-users. Lab-Box proves that if you pitch it right, people are there to back you!

Please consider going into mass-production with this product - I seriously think that (pitched correctly) this could be massive.

This is a response from Caleb:

I'm a fan of the rondinax tank design, I own around 10 of them - I found my first in a box of darkroom equipment I picked up at an op-shop for $20 since then the collection has been growing. From a design standpoint they incredibly ingenious and I admire that greatly. I have been following this labbox project for a while now since its early days, and I have to say I'm not that fond of it unfortunately. I may be biased because of my love for the original however I also have been quietly working on a very, very similar system for the past 3 years myself. Something that irks me quite a lot with the labbox is that they have not even acknowledged the use of or even inspiration from a now 90 year old design. This is more of a respect thing which I have discussed with quejai before - looking at the kick-starter and prototype , they have used original rondinax parts including the film clip, slicer and handle bracket (and probably more). I suppose this is fine for a prototype but it just makes me question their next step in regards to design and manufacture.

Anyhow sorry for getting off track, back to the scanner. As you can imagine, the scanner is a much, much more complex project all together from the amount of parts to construction and testing. For this reason, while we are still considering kick-starter we would like to start slow and steady rather and then use it as a kick-forward in a sense when the time comes. It is very easy for a project to crash and burn as you all have seen many times. We want this scanner to be successful and stick around for a while to come yet.

Cheers

 

[Prest_400]

This is a response from Caleb:





Anyhow sorry for getting off track, back to the scanner. As you can imagine, the scanner is a much, much more complex project all together from the amount of parts to construction and testing. For this reason, while we are still considering kick-starter we would like to start slow and steady rather and then use it as a kick-forward in a sense when the time comes. It is very easy for a project to crash and burn as you all have seen many times. We want this scanner to be successful and stick around for a while to come yet.



Cheers

Well, the Lab Box is interesting. Maybe somewhere down the line I'll get one, or just a Paterson, dark bag and a bunch of film. Upon seeing it I thought "a Rondinax 2.0", but I see they didn't include a "inspired by agfa design, bla bla" line. Patents are expired and so they may just reissue as new, but yes, no credit to the design team. It's as if the designers didn't exist.

Fully agree. The LS would be perhaps adequate once the prototyping and small batches have consolidated.
It does bring another scale, possibly overwhelming. Production itself should be en masse (compared to the small batch system). Just as you put, when the time comes. This is not a carboard camera (Jollylook) nor a plastic tank so the headaches would be quite larger as well.


Sent from my iPhone using Tapatalk

 

[mani]

It wasn't my intention to sideline the discussion into the pros and cons of the Lab-Box: for many people new to film photography (like me) the history of a project like that is less significant than the sheer fact of being able to buy a new unit, with everything hopefully guaranteed to keep working for the foreseeable future, and a current manufacturer of spare parts and possibly new accessories (such as the promised temperature controllers).

I think a small run of scanners is appealing to those who themselves have the capability to fix anything that may go wrong with them.

But a larger manufacturing venture, with spare parts, guarantees and maintenance plans long into the future would probably appeal to a very much broader range of new film users. Just my opinion.

 

[Jockos]

Really looking forward to it. I was planning on printing a set of images for our new dining room, and will be holding back until I get the new scanner!

 

[quejai]

@mani re. market readiness: It will be interesting to see how it goes. I think we'll work something out.

But a larger manufacturing venture, with spare parts, guarantees and maintenance plans long into the future would probably appeal to a very much broader range of new film users. Just my opinion.

In terms of appeal, I agree. In terms of short term repairs, I agree. But in terms of long-term repairability, in my view, it all comes down to concise, well-written documentation and having either standardised parts or easily re-manufacturable parts. Check this out. These three pages will enable any competent electronics technician to get this 1939 radio working again. http://www.nostalgiaair.org/pagesbymodel/279/M0013279.pdf
We might need a few more than three pages for the scanner, but that's the general idea. That radio can still be confidently repaired, regardless of whatever happened to Philco.

Really looking forward to it. I was planning on printing a set of images for our new dining room, and will be holding back until I get the new scanner!

Thanks, so are we. So no pressure on us to get it right, hah!

Caleb and I are each working on some film holders, and I've just built a mockup sort of thing for my holder design. Videos below show the general idea, put the film in a timing belt sandwich and take it along a conveyor belt sort of thing, maintaining curvature(you always want the film in a mathematically representable shape, either flat on a wet mount or in a curve like this, as is used on drum scanners. Too hard to represent the variable curves of film left unconstrained in a general way, meaning spatial distortion is guaranteed)(also like corrugated steel, keeping it bent along one axis will stop bending along another axis, so we end up with a system where we control all the bending rather than having some freedom for the film to do unpredictable stuff). The conveyor module is designed such that the upper and lower part of the sandwich have a return path, so the belt becomes a continuous loop, but I ran out of time to connect that up.

Importantly, what I am doing in the video should never be done for an actual scan, as the holder will block the middle of the film. If film is being loaded end-first like this, then two conveyors would be used on the edges of the film to avoid blocking the content of the film. I'm using 5mm belt, but I've found suppliers of 3mm-wide timing belt and I'll probably go for that ultimately, to reduce the size of the blocked region. That's the downside of this approach, there will be some area of film blocked by the holder. The way around this is to put the film through twice, at slightly different positions. Don't worry, I've worked out easy workflows to make this very doable. Also, I'm generally thinking that with another 3 or 4 of these conveyors film will be able to be loaded sideways, and I'm thinking that that will be the more common way to load film.
The power to advance the film comes from a motor which couples to one of the rollers (it's spent a month in the postal system now, still hasn't arrived), and to save space and cost the bolts you see in the video will probably be replaced with little rivets.
Haven't tried this particular holder idea on thicker stuff like 4x5 yet, that would probably need some less radical curvature.

TLDR: mockup of film holder shows that idea works. Hard to explain. Final version will have more conveyors, allow film to be loaded side-first, will also have a motor-powered continuous loop of conveyor belt and might be thinner than the version you see below. Film falls off in video due to not having any way to line it up easily (yet), natural instability of using a single roller, and because the timing belt I was using was too short.

https://www.youtube.com/watch?v=iOJEyi7Xdbo
https://www.youtube.com/watch?v=IWYqzxn486M

Also rederived all the dimensions of the scanner (with a few little changes), so have some nice concise engineering drawings of all the relations. Rebuilt the illuminator carriage too, that's going well. Bumped into this electronics engineer student at uni doing his PhD on switching circuits and asked about how to do the LED strobing backlight, he said our current approach (mosfets) is what he would do. Caleb's work on the case is going well, has a couple of neat design aspects that I'll keep quiet for now. We're spending more time focusing on practical issues of suppliers and manufacturing plans.

Getting there.

 

[Bandiahegyrol]

Hi,

If you succeed, i'm a potential buyer from Europe.
Good luck.

 

[Harry Lime]

Hmmm, I watched the video of the film transport.

Why not just use a large diameter drum that would rotate above the camera? That's how Imacon / Hasselblad does it. I could even contain the light source.

 

[mani]

Hmmm, I watched the video of the film transport.

Why not just use a large diameter drum that would rotate above the camera? That's how Imacon / Hasselblad does it. I could even contain the light source.

+1 to this suggestion, which was also my thought when I saw the rather painful-looking progress of the film through the 'snake' transport.

 

[quejai]

Hi,

If you succeed, i'm a potential buyer from Europe.
Good luck.

Cheers

Hmmm, I watched the video of the film transport.

Why not just use a large diameter drum that would rotate above the camera? That's how Imacon / Hasselblad does it. I could even contain the light source.

+1 to this suggestion, which was also my thought when I saw the rather painful-looking progress of the film through the 'snake' transport.

We had considered a drum, but didn't pursue it for a couple of reasons, one being that it would be too expensive to find/get some made accurately enough. Honestly yeah it could be done, but I'm not sure what would be gained. The snake holder (I like the name) really is hard to explain without a video of it working in its final form, which I'm working on, but hopefully then you'll see why it's our preferred approach at the moment. Remember that the scanner is designed to be able to change holders easily, ie for a flat wet-mount holder, and a flat version of this snake holder for slides and large format. Perhaps we'll end up with a snake holder with fewer, shallower bends as a general purpose middle ground for all film...

 

[BuzzyOne]

IMO I'd be afraid of scratching hell out my negatives pulling them through such severe curves captured like that. I've got some older negs that are probably too brittle to do that too as well.

I haven't read the entire thread, just watched the videos, so maybe I am missing something. I'd rather have the film held static and move the scanner below it.

 

[quejai]

Hi there,

We would just like to elaborate further on the drum idea here. Firstly, thanks for the input, it is interesting because we have this considered in-depth before but have determined that it offered little benefit compared to the design complexities it requires. With our current design we would have to reposition the camera and light simply to fit the drum along with other major structural and operational changes to get it working. We would have to opt for a completely different light source and somehow integrate in the drum which the whole assembly would then have to be completely removable to actually mount the film. Another thing to note is you would still have to wet-mount to avoid Newton Rings (then you need a dedicated mounting station) - at this point wet mounting a flat glass sheet is much simpler and easier achieving exactly the same result using our plate holder.

Aside from the extra work and skill required from the user for a drum based solution, we need to think about certain design and fabrication intricacies including sourcing the drums, precision machining them (even slotted drums for dry mounting), driving them, concentricity and a whole lot of physics etc. It is possible but at certain costs which we really don't believe will translate to much benefit for users. This is unlike PMT scanners that actually require this complex type of set up to work. As quejai has mentioned, it is hard to understand why we have chosen this design without seeing it in the wider context of the scanner, I think we will work towards a better video that illustrates all this. With all this said, we are still considering pursuing this idea perhaps as an optional modification of sorts afterwards.

Again, thank you for the input it is much appreciated - keep it coming!

IMO I'd be afraid of scratching hell out my negatives pulling them through such severe curves captured like that. I've got some older negs that are probably too brittle to do that too as well.

I haven't read the entire thread, just watched the videos, so maybe I am missing something. I'd rather have the film held static and move the scanner below it.

Hi, for front loading of film only the rebates or outer edges of the film will be in contact with the mechanism. Let us remind you this is just a simple proof of concept video, we are continuously working on the design and testing it and it may very well be completely different from what you see now. We will of course test it on all film types we can, different base thicknesses and conditions. This is also just one of the several film holders we are producing for the scanner - older or more troublesome film would be better suited to our wet-mount holder or flat transport type holder.

Thank you for the feedback.
- Caleb

 

[jzagaja]

Best would be avoid complicated drum and wow/flutter effect, you can bent film as cine scanner do and immerse in tank or use very soft light. Question remains how to sample then does linear 8-12K module exist for the task?

 

[Jockos]

Any updates? 🙂

 

[quejai]

Any updates? 🙂

For sure. It feels slow on our side too, and I'd love to be able to do this full time but that's not going to happen.

Kept building the snake holder, but it turned out to be a bit too fiddly the way I was going with it. Gaps were fractions of a mm in places where it should have been at least 2 or 3. I've worked out how to get around that by a slight redesign (6mm support rods instead of 8mm, thicker and more sturdy lane supports). I've also worked out how to make it a single-load holder, instead of having to load it twice like I was going on about earlier.

On Thursday I felt like spending the night on the scanner instead of uni work, so I whipped up a prototype PCB for all the electronics. Still need to wire it up properly, but once the electronics is done it'l be much easier to play with the moving parts. So much thinking has been involved with the electronics, it's like every hour in the workshop is backed up by 20 hours of thinking.

Built a test circuit for the LED strobing system. I can get strobe durations down to the microseconds, although I haven't really been pushing it yet. Strobe duration is important to minimise in order to keep the sensor moving at a quick rate, and yet eliminate motion blur on the scale of microns in order to avoid smearing - my tests indicate we should be able to achieve this easily.

Found a great local supplier of acrylic for the panels, also made some assembly jigs that make it much easier to throw the chassis together accurately. Was going to cut a new set of panels on Thursday but it got too late, might do a few tomorrow.

Also worked out a super easy, inexpensive way to implement aperture control for microscope objectives, which tend to have aperture diaphragms in the light source and so not in the objectives themselves, since as we're not using kohler illumination we can't put our aperture in the light source and so need some other way to implement it.

Here's one side of the prototype PCB, and the PCB installed with the other side visible. It'l probably be all on one PCB eventually, not with those extra boards plugged in. The red wire is a little test of the wire wrapping technique I'll be using for wiring up the board.

 

[marekvesely]

This is amazing. I've been following the progress for some time now. I just got totally screwed over by Plustek Europe when they sadly told me (after four months of service!) that my brand new 2000$ OpticFilm 120 scanner is "unrepairable" - that means they aren't currently able to produce 100% working sensors without yellow color banding & IR channel issues. This is something that only few people know and it is something that I'm currently looking into with the help of local distributors.

Your project does have an insane commercial potential and many of us would pay 1500$-2000$ for it. This is something I'm definitely 100% supporting. Do you have a current basic road-map (as far as development/producing/selling) for this project? This can take years and years without other people support/funding. I bet many of us would love to help out!

Thank you! Keep up the great work. This is gonna be big.

 

[Jockos]

Kept building the snake holder, but it turned out to be a bit too fiddly the way I was going with it. Gaps were fractions of a mm in places where it should have been at least 2 or 3. I've worked out how to get around that by a slight redesign (6mm support rods instead of 8mm, thicker and more sturdy lane supports). I've also worked out how to make it a single-load holder, instead of having to load it twice like I was going on about earlier.

Sounds great, it'll be interesting to see it in action, especially with the larger formats! You were planning to make it able to scan whole 35mm rolls as well right?

Built a test circuit for the LED strobing system. I can get strobe durations down to the microseconds, although I haven't really been pushing it yet. Strobe duration is important to minimise in order to keep the sensor moving at a quick rate, and yet eliminate motion blur on the scale of microns in order to avoid smearing - my tests indicate we should be able to achieve this easily.

How many exposures per second are we talking about? Are you doing any post processing in the scanner or are you sending everything to the computer? I'm assuming you're using USB2, is it enough for all that raw data?

Great job so far by the way!

 

[jzagaja]

Is it possible use affordable premium ccd camera like Kodak KAI-8050 with GigaE interface? Best monochrome version with tripple flashes+HDR.

 

[quejai]

How many exposures per second are we talking about? Are you doing any post processing in the scanner or are you sending everything to the computer? I'm assuming you're using USB2, is it enough for all that raw data?

Great job so far by the way!

The more the better! I'll let quejai tune in on the rest of your questions. It will be a USB 3.0 connection with pp on front-end ATM.

Is it possible use affordable premium ccd camera like Kodak KAI-8050 with GigaE interface? Best monochrome version with tripple flashes+HDR.

Jack, the sensor format is larger than the standard we have designed for. There would be vignetting and other aberrations without necessary adjustment to the optics.

That said, as its open source and modular design so I'm sure it can be done. We have designed the scanner around using off-the-shelf machine vision cameras to ensure future support and upgradability. There are a few machine vision cams that use this sensor, notably the PixeLink PL-H968BXG (if that was the one you were referring to). The cam we have gone with is USB 3.0 based however you raise an important point of having support for various common MV interfaces such as firewire and future standards eg CoaxExpress. Thanks for this, we shall look into this further.

Also some updates on my end I have just secured a CNC router of my own after a very long wait. This should mean some much faster progress with alt holder, case designs and more……hopefully! 🙂

Caleb