topic Re: Historgram for multiple photos? in EOS DSLR & Mirrorless Cameras

Historgram for multiple photos?

Tintype_18 — Mon, 19 Apr 2021 12:17:09 GMT

I was taking some photos with my T7 a while back. The histogram was on the screen and bfrought a questionto mind. I have played with the histogram on DPP4. Could one use the "graph" on the histogram to adjust settings for f-stop, ISO, shutter speed, etc.? Thanks.

Re: Historgram for multiple photos?

rs-eos — Mon, 19 Apr 2021 12:40:32 GMT

I'm not sure what you're asking. I haven't used DPP, but are you speaking to the ability to drag on various zones in the Histogram (what you can do in Lightroom) to adjust exposure, shadows, whites, etc.?

If so, the histogram is just a visual representation of the quantity of pixels at each level. Camera histograms are non-adjustable in the sense they just show a read-only view of the photo's data.

Also, while dragging zones in a photo editor's histogram would change exposure, shadows, etc, it would not in any way affect the f-stop or shutter speed.

Re: Historgram for multiple photos?

jrhoffman75 — Mon, 19 Apr 2021 13:26:58 GMT

@Tintype_18 wrote:
I was taking some photos with my T7 a while back. The histogram was on the screen and bfrought a questionto mind. I have played with the histogram on DPP4. Could one use the "graph" on the histogram to adjust settings for f-stop, ISO, shutter speed, etc.? Thanks.

Expanding on Ricky's response:

1. if you are looking at the histogram when you are playing back an image already taken the histogram is history - it shows the image as you captured it.\

2. if you are using LiveView you can't adjust anything by using the histogram, but you can adjust camera settings and see how the histogram changes.

Re: Historgram for multiple photos?

Tintype_18 — Mon, 19 Apr 2021 15:18:33 GMT

Need to be a bit more precise here. The camera shows the histogram on the LCD screen. I'm thinking I can take additional photos to "shift" the peaks and alleys of the histogram to affect the photo. Sort of "editing" with the settings.

John Hoffman's item #2 is what I'm looking at.

Thanks to all.

Re: Historgram for multiple photos?

ebiggs1 — Wed, 21 Apr 2021 14:31:44 GMT

"... I can take additional photos to "shift" the peaks and alleys of the histogram to affect the photo."

The best place to use the histogram is in post editing. However, the most important parts are not the peaks and valleys but either end. The histogram should go completely to each end. If you take a shot and notice that is doesn't you can try a different exposure setting to make sure that is does extend to both ends. The bottom line of the histogram that goes from left to right shows 0% brightness, or black, to 100% brightness, or white. Oh, BTW, your histogram should not spill over the ends either.

Always shoot Raw so you get the very most editing ability.

Re: Historgram for multiple photos?

kvbarkley — Wed, 21 Apr 2021 21:43:28 GMT

You can only move the whole histogram to the left or the right. You cannot change the dynamic range (except with digital lighting optimiser). Besides, how will you tell the camera which to adjust: aperture, shutter or ISO?

Re: Historgram for multiple photos?

jrhoffman75 — Wed, 21 Apr 2021 22:02:50 GMT

Correct. Not all scenes will have a full 11 Zone range. Ansel’s job would have been a lot easier if they did.

Re: Historgram for multiple photos?

Waddizzle — Wed, 21 Apr 2021 23:33:38 GMT

@kvbarkley wrote:
You can only move the whole histogram to the left or the right. You cannot change the dynamic range (except with digital lighting optimiser). Besides, how will you tell the camera which to adjust: aperture, shutter or ISO?

Actually, you can "stretch" the dynamic range to a fairly significant degree. I have watched a couple of astrophotography videos on YouTube that show you how to do it. You will never go completely side to side. But, you can take an image that is butting up against one side and stretch it out towards the center quite a bit.

Re: Historgram for multiple photos?

jrhoffman75 — Wed, 21 Apr 2021 23:57:33 GMT

@Waddizzle wrote:
@kvbarkley wrote:
You can only move the whole histogram to the left or the right. You cannot change the dynamic range (except with digital lighting optimiser). Besides, how will you tell the camera which to adjust: aperture, shutter or ISO?
Actually, you can "stretch" the dynamic range to a fairly significant degree. I have watched a couple of astrophotography videos on YouTube that show you how to do it. You will never go completely side to side. But, you can take an image that is butting up against one side and stretch it out towards the center quite a bit.

Please post a link to this. And remeber, we are talking in-camera, not in post.

Re: Historgram for multiple photos?

Waddizzle — Thu, 22 Apr 2021 00:17:45 GMT

@jrhoffman75 wrote:
@Waddizzle wrote:
@kvbarkley wrote:
You can only move the whole histogram to the left or the right. You cannot change the dynamic range (except with digital lighting optimiser). Besides, how will you tell the camera which to adjust: aperture, shutter or ISO?
Actually, you can "stretch" the dynamic range to a fairly significant degree. I have watched a couple of astrophotography videos on YouTube that show you how to do it. You will never go completely side to side. But, you can take an image that is butting up against one side and stretch it out towards the center quite a bit.
Please post a link to this. And remeber, we are talking in-camera, not in post.

Ah, no. My mistake. I was speaking about post processing. No in the camera.

Re: Historgram for multiple photos?

ebiggs1 — Thu, 22 Apr 2021 13:59:38 GMT

"My mistake. I was speaking about post processing."

Yet you can increase the shadow or highlight area in camera with exposure. Perhaps not the total DR but the apparent DR increase in these ares might help the shot.

But Raw files and post editing is the best use for sure.

Re: Historgram for multiple photos?

Tintype_18 — Wed, 28 Apr 2021 20:12:06 GMT

ebiggs1, I agree. I'm still learning the camera and getting to where I like to experiment with different settings. Example- took some photos of wild flowers yesterday. Some were a disaster on manual. A newspaper photographer said he used TV exclusively. Tried it and got some good shots. BTW, I usually take jpg and RAW photos as the T7 will do both at the same time. RAW are taken in case the are edited and submitted to a publisher. Family and other casual shots are jpg only.

Re: Historgram for multiple photos?

ebiggs1 — Thu, 29 Apr 2021 14:21:06 GMT

"RAW are taken in case the are edited and submitted to a publisher. Family and other casual shots are jpg only."

With today's post editing software there is no reason to not shoot Raw exclusively. The fact you u/l your photos to your computer is all that is necessary as the Raw conversion is seamless and automatic upon import. If you never edit any shot you still have the jpg conversion right in front of you ready for any reason.

Did you know? When you shoot jpg in the camera your camera does the conversion. So what you may ask? Well, when it does that conversion it compresses the Raw data and deletes it. It is gone forever just thrown away never to be recovered. It "guesses" what is important and what is not. You bet it mostly does a good job but it can't do what human eyes can see and tell the editor to do. On every shot your camera takes, it records everything at its highest resolution. That is what Raw files are. That is why they are more editable than jpg, too.

Canon knows this and offers the free for Canon owners the very good editor DPP4. Raw + jpg just tales up extra space on your SD card!

Re: Historgram for multiple photos?

ebiggs1 — Thu, 29 Apr 2021 14:45:56 GMT

"Some were a disaster on manual. A newspaper photographer said he used TV exclusively."

I am not a Tv fan at all. I am also not a manual fan either. I use Av and P mode almost exclusively. Upon occasion I do need Tv but it is rare.

I know modern DSLRs have manual mode but they really aren't designed or set up to make good use of it. At times I know it is a must but not very often. Even back in the olden days the first automatic film cameras like my A1 were Aperture Priority which really is the better choice of the two, IMHO, of course.

Probably the main most reason for Av is, you have full control over the aperture. Why is this important? It allows you to have control over the depth of field (DOF). Tv does not.

As a beginner I would advise you to avoid full manual, for sure, and Tv, probably, for now. When you u/l your photos to the computer, DPP4, you can notice the exposure settings. After a while you will start to see what works and what doesn't work so well. Take lots of shots as experience is the best teacher.

Re: Historgram for multiple photos?

Tintype_18 — Fri, 30 Apr 2021 00:41:21 GMT

I have DPP4 and learning it. I like to experiment with settings to see the results on Live View. Some are good, others are lousy with nothing showing which leads to the Delete button. My computer will show detail on jpg photos when I right click- date, camera, f-stop, ISO, shutter speed. I take few photos so I don't run out of film.

FWIW, I was reading through some of the guidelines for magazines. One wanted untouched RAW so their staff can edit them. Thought that was unusual.

Thanks for sharing your thoughts!

Re: Historgram for multiple photos?

ebiggs1 — Fri, 30 Apr 2021 13:19:41 GMT

"... wanted untouched RAW so their staff can edit them."

I would never send an unedited Raw file to anyone. Never! Reading is good but reading the wrong things is not so good. Especially when you are trying to learn. Sounds like you might want to take some of those places with a grain of salt.