HOP 13: Understanding The Histogram

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What are your thoughts about today’s show? We’d love to hear from you!

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This was a great idea for a topic as it is something users see most of the time in photography software but understand the least.

The RAW software for my Fuji camera has 3 different modes.
histograms

I wonder how common this is, and if explaining the advantages between them would be a good followup.

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Interesting dialogue box. Thanks for the suggestion :fist_right:t5::tumbler_glass:

I realised while writing my newest post in the general photography forum, that colour profiles and what the hell they are would make a suitable connected topic for a show, as they will set what possible levels will be shown in the histogram.

Using the wrong colour profile can mean you end up lacking some of the colours and intensity values in the pixels, or pumping them up artificially.

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Hey great episode! I’ve never really been clear about what I was looking at with photography histograms. The engineer in me has one nagging question though: What exactly does the y-axis represent here? Is it just a pixel count of the number of pixels that fall into that particular dynamic range band? That would be my guess, but unless I missed it, I don’t think you actually said what the height of the histogram technically represents.

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Thanks for the comment. Correct, I didn’t say what the height actually meant. And honestly, I’ve NEVER learned an actual value on what the x and y are. I know that once the plotter is at 75% to the top of y, the measurement is getting close to clipping. Whether it’s the whites, exposure or highlights. For shadows and blacks, roughly 20-30% of y is when you’re warned about crushing the blacks and shadows where you’ll actually lose detail in those areas of the image. But, I’m not a guy that has a problem with having my shadows almost clipped. I like darker shadows and blacks in most of my images because of the contrast. Technically I shouldn’t, but that’s just my taste.

In a future episode we’ll come back to the histogram as I cover the curves tool in both Lightroom and Photoshop. The curves tool is super powerful and being able to see the histogram while working the curves makes the editing process super easy and/or creative.

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What can someone with more experience tell me about this histogram?

I’m working on improving the lighting in my YouTube videos. This is the best spot to record, but it’s in front of a big window. Lately it’s been cloudy and there’s snow on the ground, so the light coming in is very cool and it’ll be too bright on my face, if I try to make sure the purple look good. So I figure that’s not great and I should control for light, so I have a ridiculous make shift softbox and a light blocking curtain.

I forgot ISO was on auto, and I think it’s too high here.

Thanks for the show! Great content for a newbie like myself.

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Go to f/3.2 or something and take a look. That f/1.8 seems a bit extreme.

The reason why I have f/1.8 is to get in as much light as possible, so I don’t have to crank the ISO (here it is again set to automatic). I’m recording videos in a room with mixed light sources, so right now this is all with lamps only, blocking out the sun/snow light.

I just did a video on ISO 3200 and it definitely had more noise than I would prefer.

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Yeah this is tough. Are you in the US? Or Europe? I see the shutter is set to 1/50. The histogram looks like it will be an easy-ish correction considering the wonky light you’re dealing with. Shutter to 1/25, f2 or 2.8, ISO 1200 is what else comes to my mind. Else, you’re going to have to adjust the exposure and/or highlights in post.

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I’m in the US. I like to pretend I’m a fancy film maker, so shutter is 1/50, and I’ve heard shutter should be 2x fps, and I’m shooting at close to 24fps.

Not that you need to go through and dissect my lighting issues. I only replied to this thread to try to understand what that clip in the middle meant. I’m wondering if it’s just because that background is so purple and there’s not much else in the shot?

I have added 2 extra soft light lamps in the room, and I think that’s going to help bring down the ISO so I can bring up the F. That should help give some definition to the art on the wall.

Thanks for the replies!

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lol at “pretend I’m a fancy film maker.” Love it! Create and dominate, my man :fist_right:t4:

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And yes, those extra lights will help. :fist_right:t5: