darktable ep 068 - Negadoctor

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  • Опубліковано 4 січ 2025

КОМЕНТАРІ • 81

  • @miklosmuller7267
    @miklosmuller7267 4 роки тому +9

    Hey Bruce, I must say your vid completely changed the way I use negadoctor, and I am getting much better results since! Thanks a lot for sharing, and keep up the good work! Miklos from Hungary

    • @audio2u
      @audio2u  4 роки тому +2

      Glad to hear it! Thanks!

    • @jimschmidt7303
      @jimschmidt7303 4 роки тому

      Hello Miklos. I asked Bruce a question he was not comfortable answering which you may be able to. How does the image quality of a scanned negative compare to a modern day camera? When I try to do long exposure photography for milkyway photos my Nikon D3200 is just okay. I recently acquired a 35mm film camera and am debating trying some nighttime photography with it. Turn around time for film processing here in the USA is about 3 weeks. Thanks for any opinions you can share.

  • @mickehog76
    @mickehog76 4 роки тому +6

    Nice to see you again :). I hope you had a great vacation.
    Great video as always :).

    • @audio2u
      @audio2u  4 роки тому +2

      Thanks, I did! :)

  • @KevinSaruwatari
    @KevinSaruwatari 3 роки тому +3

    Thanks Bruce! I have on-going problems with this module. I've found selecting the border seldom works very well at getting the film color (like the landscape) because (my theory is) it hasn't been exposed to the light the frame has. I generally pick the deepest shadow in the image (or an adjacent image on the same film in the same light) and the results are generally (not always) better. Even still (!) it is very fussy and not easy to correct because white balance tools don't work. If the film is digitized with a camera, it is very important that the camera white balance matches the light source. And even still (!) it is temperamental to adjust color. I've seen this with all forms of digitizing (watch a vid on Noritsu and Fuji scanners, even in high production the operator tweaks each image) not just darktable. My attempt to fix this is I'm starting to shoot slide.

    • @audio2u
      @audio2u  3 роки тому

      Interesting. Scanning megs and slides is not something I do, so my total experience in the field is limited to what you saw in this video! 😃
      Well, maybe not, but close enough. I've digitized a handful of other images, but with a cheap and nasty scanner that did such an average job that I never spent 🔐 whole lot of time trying to develop the images.

  • @smori7678
    @smori7678 2 дні тому +1

    Is there a way to flip the negative on import? I use a digital camera to scan the emulsion side and need to flip each one individually. Would like to batch flip or flip on import.

    • @audio2u
      @audio2u  2 дні тому

      What I would do for this, is process the inversion for one image. Then, create a style that simply includes that module. Then, when you scan a bunch of new images and import them, apply that style to all of them.

  • @didiMao
    @didiMao Рік тому +1

    Hi Bruce. I just started using DarkTable today and this is immensely useful

    • @audio2u
      @audio2u  Рік тому

      So glad to hear that! Cheers.

  • @LautaroLopezVara
    @LautaroLopezVara 2 роки тому +2

    Incredible Bruce, thank you so very much! Very well explained and simple to grasp and understand!

  • @andrewgreig1197
    @andrewgreig1197 4 роки тому +1

    Hi Bruce, On seeing this video I was provoked to use my abundant time, thanks to Covid, to revisit scanning of some images for which I had used an Aldi film and slide scanner, I thought that the dust on those images was because the slides were dirty, but it turned out to be the scanner. So I set up my tripod on a table and with a "Lightbox" of 5" x 4" screen size (6 x AAA bateries) and some masking with black card I used my camera with a Macro lens to perform the task. I shot with emulsion side up. I tried using the whitescreen app on my phone as a lightbox, but the macro lens picked up the array of LEDs and produced a polkadot background to the image. Interesting thing to note is once working on the positive image the slider directions for exposure (at least) are reversed.

    • @audio2u
      @audio2u  4 роки тому

      Maybe that explains why I felt all the sliders were contrary to what logic would suggest! Draggin right would make blacks blacker, etc.

  • @MustWorkWeekends
    @MustWorkWeekends 4 роки тому +3

    The print properties should be used to compensate for the paper properties on which the scanned negative will eventually be printed on. Matte and glossy papers each have their own nuances. In order to get the highest quality end print you should take into consideration the final media and prepare the image file for that media. Also, when selecting the highlights, you should sample the brightest part of the images, not just part of the sky in general. Remember that you are trying to maximize the dynamic range of an image. The clouds have a lot more information than is being reflected in the way you processed this image. I'm loving your videos. I have been a Photoshop user since version 2.5 and I've been looking at darktable as an alternative. Thanks for all your efforts.

    • @audio2u
      @audio2u  4 роки тому

      Great info! Cheers!

  • @petroski82
    @petroski82 4 роки тому +1

    Really useful, thank you a lot. I will try this module during the weekend and see what I can obtain with my 35mm negs

    • @audio2u
      @audio2u  4 роки тому +1

      Cool! Have fun!

  • @joaovtaveira
    @joaovtaveira 4 роки тому +2

    23:16 But shouldn't the selection be only on the highlights area?

  • @rjbiii
    @rjbiii 5 місяців тому +1

    Did you ever work out how to fix the color of tungsten balanced film conversion? I've been getting stuck on that.

    • @audio2u
      @audio2u  5 місяців тому

      Sorry. I don't have any neg film to play with!

  • @jimschmidt7303
    @jimschmidt7303 4 роки тому +1

    Hello Bruce. Thanks again your excellent catalog of videos.
    I have some questions that your answer may save me from chasing an idea I have been throwing around in my head. So the main question, modern camera sensor (24 mega pixel) vs. film & slides. I am curious how the image quality of the processed scans compares to similar photos taken with a digital camera? Have you seen any advantages in photo quality by shooting with film and scanning the negatives/slides over taking photos with a digital camera? I have done some research on on the internet of people scanning or taking pictures of slides and negatives when I revisited this video. It appears people's results vary on image quality of the scans of the slides and negatives.
    This past year I have been trying my hand at long exposure Milky Way photos using a star tracker. On my Nikon D3200 at about 2 minutes of exposure I get a noticeable amount of hot pixels, at 4 minutes they are quite noticeable. The hot pixels are on top of the splotchy noise going on in the sky. Following astro-photographers videos to try and reduce noise I have been shooting iso between 400 and 1600. Above 1600 the D3200 gets very grainy with noise. I am hobby photographer and buying a better camera body just seems to be a waste for me when I only pull the camera out a few times a month. I have had some success using Darktable removing hot pixels and the noise. It usually takes me about an hour of processing on a Milky Way shot to deal with the noise, hot pixels and light pollution yellow hue near the horizon. Even out in farm country of the Midwest of the USA it is amazing how much light pollution a small town generates.
    This idea of film occurred to me when I recently purchased a Nikon 28mm lens on ebay that came with a Nikon N90 film camera. I am thinking about purchasing a roll of slide film to try some long exposure images to see how the scanned slide photos compare to digital images.
    Any opinions and knowledge you could share would be appreciated. Sorry if I seem to be rambling. Thank you.

    • @audio2u
      @audio2u  4 роки тому +1

      Jim, I can't help you a great deal here, as I don't scan any film myself. When I did this episode, I had to get viewers to submit film scans that I could use.
      Everything you're saying makes sense though. Digital sensors DO generate hot pixels which film doesn't do, so there's always going to be some work required to clean them up in post.

  • @Trev740
    @Trev740 2 роки тому +1

    Fantastic informative video!

  • @mehsmehmeh
    @mehsmehmeh 6 місяців тому +1

    Great video Bruce!

    • @audio2u
      @audio2u  6 місяців тому

      Thanks! Glad you enjoyed it.

  • @stephenward5133
    @stephenward5133 3 роки тому +1

    I’ve just started shooting film again after 20+ years and getting film processed they offer scanning as an option but different companies offer different scan qualities. I haven’t got a scanner so what is the minimum quality I should seek? They offer different DPIs and jpeg or tiff (sometimes). I am intending to shoot B&W. Thanks

    • @audio2u
      @audio2u  3 роки тому +1

      I would say take tiff over jpeg, and the highest resolution they can offer.

    • @stephenward5133
      @stephenward5133 3 роки тому +1

      @@audio2u it’s odd some of the companies here in the UK do higher definition jpegs than others doing tiff. And the cost differential can be excessive. Thanks for your response.

  • @europlatus
    @europlatus 4 роки тому +2

    I was very interested in this video because I've been using negadoctor a lot recently for my long-term project of scanning decades of negs after having tried Lr/Ps, RawTherapee and various other solutions over the years. Negadoctor is impressive and I've been getting some great results with it. When I haven't had good results, it's often the quality of the neg, some of which were shot on old instamatic type cameras or cheap compact ones.
    Something seemed very off with the colours of that second photo you worked on. I'm wondering if the black bars at the top and bottom should have been cropped out, which might have affected the calculations. Or maybe the neg has degraded over time. Usually I find that the positive suddenly starts to look good at the stage of colour correcting the highlights in the second tab. This step seems to be the magical "ah, that's what it should look like" step. But for some reason it didn't do that with that landscape you were given.
    One thing I'm still a little unsure of is the best area to sample with the colour pickers. I noticed you generally used the whole photo, whereas Aurélien sometimes sampled just the highlights or shadows. That would seem to make sense for the colour cast correction tab, but it's not so obvious for the black density. scan exposure and print exp adjustments ones. If you have any tips on that, would love to hear them.
    Great to have you back again!

    • @audio2u
      @audio2u  4 роки тому

      Beyond what I covered in the video, I'm probably not the best person to offer tips, as I don't have any experience in scanning negs! 😃
      Yeah, something was not right in that second image, and I think you are probably on the money suggesting that the film stock had deteriorated with time, or something like that.

    • @milanleskanic900
      @milanleskanic900 4 роки тому +1

      @@audio2u I wonder, with that challenging colors on the second image, what if you try to first apply white balance to the unexposed part of the film and then enable Negadoctor module? I am getting way better results (way better in terms of not needing additional fiddling and color correcting) on my negatives with strange color casting.

    • @jayzn1931
      @jayzn1931 3 роки тому +1

      @@milanleskanic900 I tried that as well before I watched this video and after, but it does not seem to affect my results at all. I still have to do the whole color correction of Negadoctor. I use Kodak Gold which should have Daylight Balance but is very blue after simply inverting as well (I do not know if the explanation in the video is right, never heard it before) but as @europlatus writes after the highlight correction the image looks quite decent.
      I also got better results now that I used the droppers for the whole frame instead of just shadows/highlights.
      That second neg just looks like Negadoctor didn't manage to correct it properly, it looks similar to results I got from other methods like Filmlab or manual inversion, when the white balance is simply wrong but you cannot figure out how to correct it.

  • @PatrickSheridanVideo
    @PatrickSheridanVideo 3 роки тому +1

    I recently bought an Epson V600 scanner, and I'm now experimenting with various programs to scan and process 35mm and 120 negatives. I've watched a few of your videos, and they're quite informative. The Negadoctor feature in darktable seems to work well.
    Question - If I scan with SilverFast and create an HDRi file (64bit RAW data including an infrared channel), will darktable be able to retrieve the dust/scratch info from the infrared channel? Or is this some sort of proprietary file that only another SilverFast program (such as SilverFast HDR) can completely make use of? The HDRi file opens just fine in darktable, but so far I'm not able to discern if there's a way within darktable to access the infrared channel dust/scratch information. Thoughts?

    • @audio2u
      @audio2u  3 роки тому +1

      I've never heard of that file format. I've not seen it mentioned in any of the darktable documentation that I've read. So my guess is no, darktable is probably not able to read the infrared channel as a separate channel. Not to the best of my knowledge anyway.

    • @PatrickSheridanVideo
      @PatrickSheridanVideo 3 роки тому +1

      Bruce, thanks very much for the quick response. I did further digging, and discovered more info regarding the proprietary HDRi files created by SilverFast. In the following recent forum discussion, posters were hoping that Negative Lab Pro would eventually be able to access the dust removal info contained within the HDRi infrared channel.
      ("Requesting a proper iSRD pipeline" - Link not allowed by UA-cam.)
      I also found a very informative Imaging Resource article written about SilverFast's HDRi and VueScan's comparable RGBI files. It's interesting to note that this article was written in 2010, so there's been at least a dozen years for image editing programs to update/upgrade in order to be able to read and implement the dust/scratch data contained within the infrared channel.
      ("HDRi & RGBI--Archival Scan Formats?" - Link not allowed by UA-cam.)

  • @kunstsein
    @kunstsein Місяць тому +1

    Honest question. When you recorded the demonstration, you really didn't noticed (or had the thought) that the negadoctor module didn't work properly? And four years later, it still doesn't it seems. I can not generate a normal looking film positive to save my life. Is the white balance funktion broken? Maybe i'm missing something, but i am not alone.
    I guarantee you that the second image you worked on was nowhere near as blue and broken as it seems in the editor.
    Takes me literally seconds to invert a film negative in rawtherapee and set a whitebalance.
    Maybe the modul works fine but i can not understand how to use it. Giving up after two hours now.

    • @audio2u
      @audio2u  Місяць тому

      I honestly don't recall what I did in that video! I'd have to rewatch it. But no-one has suggested (up until now) that I did anything wrong.
      I will admit that negadoctor is not a module I ever have cause to use, as I don't have any colour film negs to scan.
      To my recollection, it does work as it is meant to.

    • @kunstsein
      @kunstsein Місяць тому +1

      @@audio2u Oh you did nothing wrong. I believe that the software module has a big problem. I am not quite sure why this was never mentioned before.
      ps And thanks for your videos in general. Very much appreciated

  • @charleshacker765
    @charleshacker765 4 роки тому +1

    Well, probably won't ever use this one, but interesting as usual. Really interesting lens at the end - one lens to fit everything. Wow!

    • @audio2u
      @audio2u  4 роки тому

      Same here. This video was probably the only time I'll ever used the module, too! 😃

  • @steveoc64
    @steveoc64 Рік тому +2

    How’s this for a mad plan - get a Pentax k3 monochrome just for doing proper black and white negative scans :)

  • @arrobi7666
    @arrobi7666 Рік тому +1

    Negadoctor, if turned on, makes unusable almost all other tools, for example:
    1. module exposure will make image brighter with lower exposure settings, and will make image darker with higher exposure settings
    2. module "basic curve" is inverted too - bright colors are on the left side of curve, and dark colors are on the right side of curve.
    I believe that "nagative" module must only change source to negative bw and colors AND this conversion MUST be first in module chain, THAN other modules can do their usual job perfectly
    Also I believe that it makes easier developer's life.
    I hope one of the developers will read this.
    This is a real problem - if I "scan" negatives with my camera then basecurve of my camera will be applied in inverted values to my "scan". It is very sad

    • @audio2u
      @audio2u  Рік тому

      I'm on my phone right now and don't yet have my computer set up in my new house, but something here just isn't right. As soon as I can look into it, I will, but I don't recall having any of these issues when I recorded that video.

    • @arrobi7666
      @arrobi7666 Рік тому +1

      @@audio2u
      you need proof-video?

    • @audio2u
      @audio2u  Рік тому

      Hehe, it's not that I doubt your claim! I'm sure what you have described is actually what is happening. I just can't help but wonder if there is one tiny detail that is different between your workflow and mine. And like I said, because I don't yet have my computer set up in my new house, I can't even check it for you.
      An alternate route might be for you to join the discussion at pixls.us
      You'll find a dedicated darktable section of the forum there. Maybe reach out on that board and see if someone can help troubleshoot the issue.

    • @arrobi7666
      @arrobi7666 Рік тому +1

      @@audio2u
      1 minute video is ok? or it should be shorter?
      i will record the video

    • @audio2u
      @audio2u  Рік тому

      As much time as you need! A minute would be fine.

  • @rvgeerligs
    @rvgeerligs 8 місяців тому +1

    thank you very much!

    • @audio2u
      @audio2u  8 місяців тому

      You're welcome!

  • @antipodesman
    @antipodesman 3 роки тому +2

    I think you were mistaken regarding Graham's image. That bit at the top was not unexposed film but part of a window frame. Look at the image dimensions also the area is not square to the edge of the image. Am I wrong?
    Good video by the way. Hope I get a chance to scan some old negs and use this module.

    • @audio2u
      @audio2u  3 роки тому

      You might be right. I'd have to go back and have another look at it. I remember thinking at the time that maybe the neg hadn't been lined up square, but maybe that wasn't the case!

  • @Sinar-P
    @Sinar-P 2 роки тому +1

    How and where do I find Negadoctor to download it.

    • @audio2u
      @audio2u  2 роки тому +1

      I don't recall now exactly which version of darktable saw the inclusion of Negadoctor, but I'm going to take a guess at 3.6 or 3.8. So as long as you are using a version after 3.4, you already have it. Use the search box under the histogram in the darkroom view.

    • @Sinar-P
      @Sinar-P 2 роки тому +1

      Many thanks. Its my first few hours with Linux and Darktable. I have a quick learning curve ahead. I'm coming from Windows so it's all a bit foreign. I found the module many thanks.

  • @joaovtaveira
    @joaovtaveira 4 роки тому +1

    25:20 But the histogram is not accurate. To get an accurate histogram you should go to "crop and rotate" and include only the image itself.

  • @joaovtaveira
    @joaovtaveira 4 роки тому +1

    14:28 Yes, but you left a different value. I assume that it was just a distraction.

    • @audio2u
      @audio2u  4 роки тому

      Possibly where I've edited between video takes! :)

  • @defendermodsandtravels
    @defendermodsandtravels 2 роки тому +1

    A good introduction however the newbie to Darktable (like me) is going to remain confused. I have followed this video closely but my image still has a horrible green tint and when I try to correct it the other colours go out of balance. I guess I have to work methodically through all the tutorials from the beginning to understand better what I am doing wrong.
    I paid for a Dartable course on Udemy which proved to be a waste of money. This video series is much more informative and accessible.
    Further to my initial comment above, I find that paying attention to the white balance makes a big difference. This was rather skipped over in the video which started at the negadoctor module. Take a test shot to show the white balance of the light source and apply that to the negative image before opening negadoctor and this makes a big improvement (at least for my image it did).

    • @audio2u
      @audio2u  2 роки тому

      See my reply to your e-mail. :)

  • @whatthefilm3080
    @whatthefilm3080 4 роки тому +1

    just downloaded it and i do not have negadoctor

    • @audio2u
      @audio2u  4 роки тому

      Look in "more modules". Bottom right in darkroom.

    • @whatthefilm3080
      @whatthefilm3080 4 роки тому

      @@audio2u Thanks a looooot from Greece

  • @dariuszkotarba4454
    @dariuszkotarba4454 4 роки тому +1

    Hi Bruce. May I have to You little competition (and how) ? One slider in Capture One vs x modules in darktable. I have big problem with some photo. Sorry - I contact You this way, Your two web pages does not work properly. Greetings. Darek K

    • @audio2u
      @audio2u  4 роки тому

      Sorry, I don't understand what you're asking?

    • @dariuszkotarba4454
      @dariuszkotarba4454 4 роки тому +1

      @@audio2u Bruce - thank You, I am to fast for asking You. My problem was - Capture One aplies automaticly denoising and sharpening photo which is already sharp and smooth. In darktable I aplied sharpening without knowing how to do properly, and I had sharp and ... crispy/noisy/grainy photo - simply horrible.
      Thank You. Your movies are great.

    • @andrewgreig1197
      @andrewgreig1197 4 роки тому +1

      @@dariuszkotarba4454 I use "local contrast" as one of my options, just turn it on and see if the default setting meets your need, if not just try a small amount more on the detail slider. If not enough then use the Sharpening module - turn it on and see if the default is enough. denoise is normally enough with default settings.

  • @Daniel-r7g7b
    @Daniel-r7g7b 10 днів тому +1

    Nice tutorial, Bruce. Thank you for making the time to put this together. Unfortunate that you had such poor color negs to work with. They were absolute garbage, and made your job all the more difficult.

    • @audio2u
      @audio2u  9 днів тому

      The negs were sourced from other viewers to my content, as I don't have any negatives of my own!
      But thanks for the kind words.

  • @ilaion11
    @ilaion11 Рік тому +1

    I find RawTherapee way better than Darktable. Much easier to get to good results. DT is so complicated in a very impractical way. RT is perfect, for everything, even film digitization.

    • @audio2u
      @audio2u  Рік тому

      Fair enough. Each to their own. You do realise that I don't have anything to do with the writing of the code, right? I'm simply a guy who loves the software, who is doing his bit to help other users get up and running.

    • @ilaion11
      @ilaion11 Рік тому +1

      @@audio2u I do realise, and I get it, diversion is not a bad thing and some like DT, others RT. The problem is with me, possibly, I couldn't fully get DT, the reason behind some tools algorithms and so on.

    • @audio2u
      @audio2u  Рік тому

      I'll concede that to really master darktable (and I'm not there yet!) takes a genuine investment of time and effort. I'm doing what I can, and do feel like the results I get today are miles ahead of what I was getting when I started this channel in 2018.

    • @ilaion11
      @ilaion11 Рік тому +1

      @@audio2u I have no doubt about that, but when time is limited, we ought to choose where and how to spend it and I succumbed to rawtherapee and Lightroom, and of course, Lumariver profile designer, a MUST for dcp profile based raw developers. I gave up on CaptureOne, I find it inferior to both RT and LR. This is the most I can do. I just wish I could code in DCraw...