Welcome to the forum!

As an adjunct to the Tangents blog, the intention with this forum is to answer any questions, and allow a diverse discussion of topics related photography. With that, see it as an open invitation to just climb in and start threads and to respond to any threads.

Blinkies and Histogram

keano12keano12 Member
edited June 2015 in general photography
Hello,
I heard I should try to exposure in the histogram over to the right as far as I can without clipping. Does that mean it's ok to touch? I know it shouldn't run up the side.

In some images the histogram looks fine but the red channel is blinking. In the image the subjects pink shirt has some blinkies but the overall histogram looks fine and exposure. Can I reduce this color channel in post?

Comments

  • Ok... After doing some research it seems those histograms are set for jpegs. RAW files are 2-3 stops safely under so I well under. It is too bad they don't have a histogram in camera for RAW files.

    I know shooting in neutral also reduces the highlights but with the safety of shooting RAW once you are aware of it I should be fine.
  • TrevTrev Moderator
    edited June 2015
    Keano,

    I think you are missing the point re camera LCD and 'blinkies'.

    You should by all means expose correctly as much as you can as the histogram you are seeing is from the embedded jpeg file in the RAW file, so you still judge by that.

    In fact, and I don't care if you read about RAWs being safely 'under 2-3 stops', that's very bad, because if you then open them up they will be 'muddy';  it's totally fine to actually slightly over-expose a RAW file, in fact I do so consistently all the time as that will 'clean' up colours, skin tones and you can safely bring back exposure on them in post.

    No matter the camera, all Digitals have a lousy dynamic range, so it's best to slightly over-expose, bring them back in post because that also reduces shadow noise.

    Channels usually clip if the white balance is out, and the red channel is usually the worst culprit. If you have an 'individual RGB channel' viewing option on back of camera in LCD, you should have nearly all the RGB channels matching up with the troughs/peaks and if they are pretty much aligned, you are fairly good with WB. (generally).

    So don't be mislead by RAW you can bring anything back, you can't, but you most certainly can if pretty much right when shot, or, and as I said I do this virtually all the time, slightly over-expose, have some small blinkies (in the relevant highlight parts of the image like wedding dresses) and it will work just fine.

    Also, when bringing back images in post, I usually bring them back too far if I need to see details in wedding dresses, but I export out as PSDs and work in Photoshop to re-open up the shadow tones, leaving the highlights alone.

    Trev



     
  • I think I see what your saying. With the few blinkies I see I should be safe as when I open up the RAW image it will be look more dull and allow now to pull out highlights if need be.

    You're the red channel is the main culprit. I'll try white balancing. I have a color checker passport.
  • TrevTrev Moderator
    Yep, absolutely you will be fine.

    When shooting say a couple against a nice sunset and there are things like great rocks/beach in the middle, if you expose 'correctly' for the sky, that foreshore/items will be black as pitch, so I deliberately over-expose the sky by 1+ stop/s to bring up some shadow details, but when I have the couple in the frame and lit from front with flash, I will so then deliberately over-expose them by that same 1+ stop.

    That way, when I then under-expose in my RAW convertor to bring back the couple, the sky will come back at the same rate, leaving both sky/couple in a great exposure.

    This saves a hell of a lot of local brushing, so once exported out as a PSD file in that state, I then open up those shadows sometimes by a full 1.5 stops and using channel masks those shadows come back up great without any undue under-exposed noise but leaves the highlights alone.

    If I had of exposed correctly for the sky and couple matched and brought back the shadows, they do contain under-exposure noise and that's much harsher then ISO noise. Normally when shooting you could print at around 12x8 no trouble without seeing that noise, that's true, but, some 'hero' shots are blown up on print/canvas/metallic, etc. to say 30x40 and hung on walls, then you do see the noise. So it's just as easy to do all the shooting that way from the get-go and have a workflow consistent.

    As many a person has said in here over the years, shoot/test/shoot/test, then shoot/test again as that is the only way to gain that confidence and to see what effects there are.

    Even when shooting a landscape, I will do the same, over-expose by a full stop to bring up shadow details and fix in post.

    Trev
Sign In or Register to comment.