>>3937127Yes, odds are you haven't masked off your light source. To DSLR scan film properly, light should only be coming through the frame you're scanning. If you have a big lightpad and light is coming from everywhere, you're going to get reflection issues.
>>3937044There is no limit to bulb mode so long as you expose correctly. To be honest, ignore everyone's very overcomplicated, pain in the ass way of dealing with long exposures so far offered in this thread. What you want to do is understand EV values (pic related). Going off this chart, we can assume those street lights are ~EV 3 or 4. Put this into your memory, from on scenes with this type of light = EV 3 or 4.
Now jump to the chart below and find your ISO column and go down it until you find '3'. Go to the right to find the exposure combos you can use. Since you want more trails, chose one with a longer shutter speed. Looks like 8s @ F11 works. Now, since you're shooting c41 and just fucking rock an extra stop and make it 16s @ F11. Or hell, do 12s @ F11.
Here's the crux of long exposures, the longer the exposure...the more margin of error you have. If the 'perfect' exposure is 16s @ F11..getting within 1 stop (perfectly reasonable for c41 film to handle) means you could be anywhere from 8s to 30s @ F11. With c41 just err on the side of overexposing and you'll be fine. For anything longer than 15s I'd just automatically double your exposure to account for reciprocity. There is no need meticulously calculating long exposures like this. Flying by the seat of your pants is perfectly fine since the margin for error is so large.
