Jump to content

Monica Rosselli

Basic Member
  • Posts

    10
  • Joined

  • Last visited

Everything posted by Monica Rosselli

  1. To delve into DPX even further, I managed to print one of the test DPX metadata with ExifTool; here they are: The transfer characteristic is listed as Printing density (corresponding to "1" value in the DPX image header; https://www.fileformat.info/format/dpx/egff.htm), which should be a logarithmic-type function; I expected it to be "Logarithmic" (value "3" in the image header), but that log transfer I read elsewhere was supposed to be meant for digital cameras footage. I wonder if these metadata are realiable, but it seems to confirm the HDS+ FilmFabriek scanner makes indeed DPX files with a logarithmic-type [Printing density] transfer function. Another thing that boggles me is that DaVinci has been used to output the files, I wonder if it would be better to ask for untouched DPX files straight out of the HDS+ scanner software. Thoughts? Thanks!
  2. Let me elaborate on the DPX file format then, 'cause I'm getting confused :). So, DPX files are RAW RGB data values with a certain gamma curve (?). Digital sensor data always follow a linear trend, tough they get converted to a logarithmic trend to better mimic human eye's perception; this process is what they call gamma encoding, and it happens (I guess) within the DPX acquisition. So the DPX files I get are RAW RGB [10bit per channel] values with a log gamma, as per FilmFabriek specs; but is this gamma curve "baked in" [hence the "flat look" setting is crucial), or is it similar to metadata? In other words, changing the wheels settings to try and obtain a flatter look (rather than a "delivery look") prior the acquisition, will directly affect the RGB values? Or is it pointless, as I can apply and tweak any gamma curve in post? Thanks again, here to learn ?
  3. Thanks for the answers. As per the scanner specs, FilmFabriek's DPX are 10bit log by default: https://filmfabriek.nl/wp-content/uploads/2019/04/FilmFabriek-HDS-2019-technical-specifications.pdf. So basically the tests I have are 10bit log DPX with "right contrast & and right saturation", while I should ask for "low contrast, low saturation", is this right? The next question that comes to mind is, if DPX are raw data logarithmically encoded, does the starting point really affect the grading latitude? In other words, a flatter starting point on the DPX does give inherently more post-production capability? Log applicable only to color negative scans-- already came across this info while doing research; what boggles me is that the DPX of FilmFabriek can only be log, as you can see here: https://filmfabriek.nl/wp-content/uploads/2019/04/FilmFabriek-HDS-2019-technical-specifications.pdf; so, by saying log is applicable only to negative, does it means the FilmFabriek does not have a right DPX option for reversal film? Seems unlikely, there's something I must be misunderstanding. DPX file format, also if I remember well, should be a log encoding of linear values from any given digital sensor. What am I missing? Thanks everyone ?
  4. Thanks for the answer. If I get the meaning of one-light/best light grade right, I think it's a one-light grade, made for overall exposure, with special attention paid to the white level of the sprocket holes, in order to never result burnt out, staying around 0,95 value; can you elaborate more on how to properly ask/set for "flat" DPX? I mean, in terms of what to aim for while setting the wheels of the filmfabriek acquiring software. Thanks
  5. Thanks everyone for your kind answers. Rollers! That's the word ?. I'm a bit reluctant to remove the metal gate as there are springs involved and I fear I wouldn't be able to put them back in place correctly; I shoved a microfiber cloth wet with isopropyl alcohol underside and moved it around, hope it's sufficient. Regarding the bulg, I read online that the orientation of the filament is very important: the tungsten filament of my bulb is almost horizontal, parallel to the gate & film: is it the right orientation? Yes, the loupe and a led tablet are a handy quick solution for inspecting heads or tails; the problem is, like in my case, where the film have been misplaced around and you have to look at frames in the middle of a roll; figured a viewer was the quickest solution! ? As you and Mark suggested, I'll keep the gray foam for now; in fact, yes it is arched, but it's not burnt nor melted for what I can tell. The casing off-- you mean the black baseplate on the underside of the unit? I'll definitely try that, just to check it and remove dust, as you'll do nowadays with a computer case. Thanks!!
  6. Hello everyone; I'm about to have some reel of old B/W Reversal & Color Reversal 8mm film (mostly Ferrania & Kodak) from the 50s/60s/70s scanned at a facility which uses the FilmFabriek HDS+; I'm planning to do a full edge-to-edge overscan, 4096x3000 resolution, and since it's for a documentary feature I chose the DPX format, which the HDS+ tech specs sheet labels as a 10bit log. I need to maximize the data latitude for grading & post-production. Since I'm pretty new to the film scanning game, I'd like to seek some advice for the instructions I'll give to the scan operator, in order to better suit my particular post-production needs. I've had some brief tests done and the first question that pops in my mind is this: - Opening the 4K 10bit log DPX tests in DaVinci & After Effects (AE with color management turned off) the image is pretty consistent across the two softwares, and looks already "developed"; meaning, il looks like the DPX has already a "baked-in gamma" that makes it look like it's already a delivery version, but not necessarly the delivery version I've in mind, as I need to be able to work on it and try different gradings; as far as I understand DPX, it's RAW data, so all the post-production latitude should be there no matter what (?), but: should I ask for a more "flat looking" settings on the FilmFabirek acquisition software? Or am I misunderstanding this? Thanks everyone, Monica
  7. Haha thank god I just passed covid, took me 3 weeks to test negative again ?, a nuisance. Anyway the headache is gone today. Now that is cleaned I kept the bulb lighted up for a while, and while there's no smoke anymore, I still notice a strange smell near the bulb compartment, a kind of smell that reminds me of very old electronics my grandfather had in his studio, maybe it's just heated metal, I honestly don't know. Hope it's normal. Interesting that you never seen the dark gray foam; maybe it was glued by the original owner? who knows. Anyway, I cleaned wherever I coul reach with q-tips and isopropyl alcohol; it took off also small traces of rust which is nice; some parts under the bulb and the metallic plate that will (I guess) hold the film down & horizontal are hard to reach and I fear to force the q-tip in too much; I took particular care to clean the cylinders (you call them spools?) where the film will be in contact; the above cylinders for fast winding are brownish, kind of brass color, while the two on the bottom are chrome; the brownish stay brownish after cleaning, so I guess it's their color and not rust or anything that could possible damage the film. Yes, I agree; altough, given the gray foam is arched and is clearly affected by heat, if it's not regularly present on Minettes and was added by the original owner to isolate light further, isn't it better to remove it and replace it with a little plate of wood, or metal? Thanks everyone for assisting me with your answers and sharing your knowledge ?
  8. Thanks so much for the answers. Yes, maybe I'm a easy scare, but that headache which I still feel made me really question the possible toxicity; if tomorrow is not gone I'm gonna alert my doctor for sure. So, I removed the yellow foam with nail polish acetone on a q tip; it removed the burnt foam almost completely, but there are still traces; I'll very carefully try to scrape the remnants with a craft knife later; and yes, I do have isopropyl alcohol, thanks for noticing, I bought it to clean the unit overall, especially the parts that will be in contact with film. I don't think the machine has never been used as the foam was well fused with the bulb, which indicates the Minette was surely kept lighted up for some amount of time; now I have a question: there is also a dark gray foam glued on the bottom of the screen; as you see in the pictures [red arrow], it's arched right above the light bulb, which indicates it suffered from the heat too; should I remove this foam too? Thanks again for your precious help
  9. Thanks a lot. I'll try to remove it with acetone then; the unit seems in overall pretty good condition except for this problem; I'm getting a little preoccupied because I still feel the dizziness/headache from yesterday; do you think that foam vapor is indeed toxic?
  10. Hi! I just bought a Minette Eight from eBay to be able to view some old regular 8mm films shot by grandfather in the 60s & 70s; it's in general good condition and sold as "working"; didn't obiouvsly put the film in, first does come a good check. So, I turned the light on and after a while I started to smell "burnt plastic", which made me dizzy, like a little headache; then I realized there was some kind of vapor or smoke coming out of the light bulb compartment, subtle, but visible enough to record a video with a phone; I unplugged the cable and removed the screen cover, in order to check the light bulb; there was a piece of synthetic foam "fused" with the bulb [see pictures]; and I suspect it's a kind of old foam used back then that is pretty toxic when vaporised by heat; I'm not 100% sure the smoke comes from the foam, but it's my best bet as there should not be any other "inflamable" parts around there, or electronics; I have no knowledge whatsoever why there's a peace of foam on the light bulb; can you help me out? Do you know if foam is regularly present above/over the bulbs of Minette editor-viewers? Can I try to remove it, trying to save the bulb? Should I replace the whole bulb, getting rid of the foam? Is this foam needed? Is the foam toxic/are there other toxic parts? Thanks a lot to everyone! For the rest, the screws and knobs seem to work normally.
×
×
  • Create New...