Suggested backlight sources for scanning film with DSLR

Yes this is it. It looks like TLCI important for color rendering in video recording… But does it matter for film scanning ?
Or am i really nitpicking here ?
I found this page with a huge database of CRI(Ra) CRI(Re) TLCI and some more color accuracy score for LED light source https://indiecinemaacademy.com/understanding-complete-led-database-testing-procedures/
I’m kinda overwhelmed with info right now…

Interesting page, thanks. According to those measurements, the highest light quality, dual-digit priced light is the Aputure Amaran AL-M9. I’d suppose that the light needs some extra diffusion layer(s) that will swallow some of the output.

Yea, definitely still interested in the v2, no need any of the pano functionality for now, but im not sure if they will continue to make v2s, hopefully they do, and not just offer the v3 from now!

I was wondering if it would make sense to set the screen of my ipad to some off-white color to offset the orange cast from the film to get more dynamic range in the reds (edit: i meant greens and blues)?

please be gentile with this newb to film scanning :blush:

I’ve been asking myself this question and tried it by taking, with my iPad, a shot of the orange mask. Then, I inverted the shot and displayed it as a backlight.

I found that it made not much of a difference, also because contrast of negatives is relatively low. Although the blue channel gets less light, it is still good enough. ETTR can help too.

Interesting, what you did in using a picture of as a light source is quite smart, didn’t think of that. Can’t wait to play with my own scanning setup.

Hi! I have a Solux 4700k, but so far I can’t figure out how to get the most uniform diffusion on the negative. Who managed to get it with halogen bulb?

Try the following things separately or in combination To get a more evenly lit negative

  • Move the bulb away from the negative
  • Insert a diffuser between negative and bulb
  • Indirect lighting: Shine the light on a white surface behind the negative

All of the above will require longer exposure. Intensity drops with the square of the distance, which means that doubling the distance will cost two stops approximately. Some of it can be equalized by shining the light through a tunnel that you could make from a can for instance.

Hi Richard,
2 things.
-Between using flash or a phone (pixel 3) which woud you recommend? I’m trying to use what I have before investing in something else.
-About using a flash as the light source. What do you recommend in terms of modifiers, white balance, distance between the negative and the flash/modifier, etc. I do not have a RA54 flter.
Thank you!

How Much Light?

I wondered how much light we actually need or want for camera scanning. The more the merrier - but let’s give it a few thoughts and measurements before getting out the big guns.

As I wrote a few posts up, I use a Kaiser slimlite plano 2454, which, according to its operating instructions, has a light density of 600 cd/m2. I ran all my tests using it as backlight but I’d like to use it as a light table to check the film strips rather than using it as an oversized backlight. Which brought up the question of how much light I actually needed. I’m not overly fond of flashes, so I had a look at a few LED panels that promised good light quality as well as a reasonable price.

According to what I see on this page, and based on what I can easily get where I live, I had a look at the specs of the Aputure AL-M9 and -MX panels. They looked good and the prices are okay. Both panels promise a CRI of > 95. Now, the question arose if the M9 had enough power or if I needed the MX.

Here is what I found

  • Aputure AL-M9, 5x8 cm, LUX at 0,3m: ≥ 900
  • Aputure AL-MX, 6x9 cm, LUX at 0.3m: ≥ 2400
  • Kaiser slimlite, 22x32cm. LUX at 0,3m: ca. 350 (measured, Lux in usual use at 2 cm: 1400)

If I’m not mistaken, this would mean that the M9 has plenty of light if I put it 0.1-0.2 m away from the negative. Other than having more power, the MX can vary colour temperature and looks more robust.

I’d appreciate comments or corrections if my calculations are wrong or if anyone uses one of the mentioned AL-Ms. Thanks in advance.

I use AL-MX and run it with 50% power most of the time to keep things cool. Blenti of light output even in half power. Also CRI is really high on MX model, tested it with CRI measuring stuff. Also TLCI values were high, what means they don’t cheat (or don’t cheat so much) on CRI values.

Thank you, @MorroW. What is your exposure (f-stop, time, iso) and the distance between the light and the film? Do you use any additional diffusor, apart from the one that comes with the device?

Rought numbers, I don’t have machines on hand right now (built for customers).
I use 5mm cap between light and original diffuuser (magnets!) and after that ca 50mm cap before film plane (custom holder).

F8, ISO 100, shutter around 1/25-1/100 depends on neg.

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You asked about flash vs phone and use of flash. Sorry to be slow.

Current iPhone and iPad have excellent light quality for camera-scan. I have no info or experience with Pixel phones. You’ll have longer exposures (~1/3 sec).

Flash is terrific but harder to rig. I have flash… 2" space… diffuser… another 2" space… another diffuser… 1/2"… film. Hope this is helpful. Stacking bamboo drawer organizers are useful to positioning all this.

Hi… For the light source locate an old shading enlarger head and flip around it. My old Omega worked truly well. The bulb is shading amended and the glass ingests heat and has hostile to Newton ring capacity. Simply ensure the bulb is acceptable. I wound up requesting another one on ebay that wasn’t vulgarly expensive and has endured pleasantly.

Hello,

it seems to me that Solux 4700k bulb is discontinued. At least I couldn’t find on in EU. But I’ve found https://store.waveformlighting.com/products/filmgrade-flicker-free-a19-led-bulb?variant=16012086673510 this “FilmGrade” high CRI bulb, would this be a good alternative?

Thanks in advance!

The specified CRI of 95 means that this bulb should allow decent colour rendering. The power equiv. of a 60 Watt bulb seems low. Be prepared for longish exposure times.

I purchased the Skier Copy Box III after reading this thread. Got it last week. Tuned it on, made about 10 scans, light suddenly goes very dim. Turn off power at wall, dim light remains on inside the box fo a a couple minutes than eventually turns off. Tried the box again a bit later, light came on at full power again, made a few scans, same thing happened, lights went dim. Looks like this box I got is faulty. I’m in Australia and have tested on two different adapters.

Pretty disappointing. Looking at the price (279usd) you are mostly paying for the film holders if like me you go for the 135+120 option. Now trying to decide weather I should just keep it for the film holders and use them on an ipad or get an exchange so that I can use the film holders in the neat little grooves that come with the copy box and get that nice amount of seperation from the light source. Using the Skier film holder on my ipad there will be very little seperation. Shame, was really hoping this box would be my film scanning solution.

Looks like it - unless the light has some kind of overheating protection.
Iˋd get in touch with the seller and ask for a replacement.

That’s a shame indeed. As Digitizer is speculating, it sounds almost like an overheat protection issue. Any chance of testing a fan in front of the ventilation holes to see if the problem remains?
I have the V1 Skier box and it gets quite hot, so now I’m curious to see how the V3 which is supposed to arrive here today will work… :-/