Geo_Drone
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Flight distance : 2795098 ft
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Mzp Posted at 7-14 06:03
Thank you Geo. Yes I am aware of Youtube taking long time to process HDR video. I think it can take even longer than an hour to process from SD->HD->HDR. I did not know Youtube compresses dark / black this way, good to know to give it a little bump so it doesn't get compresses. Wanted to ask you a question on HLG / D-Log / A-Log shooting, I think you mentioned you align to the right of the histogram to prevent overexposure. I use ND filters during the day, i.e. ND32 when it's bright and I normally shoot at -0.3 to -1.3 manual exposure. I do this so I can capture overly bright, shinny objects such as reflection of a sun on white car roof, white house roofs, white water ripples. Wanted to ask you what you meant by aligning to the right. I normally end up with a --0.3-1.3 on exposure (I understand this is subjective and can be different on different lighting conditions) , but my shadows end up being a bit dark even though I end up with virtually no overexposure on the specular or highlights. I then just raise the shadows a little in Davinci Resolve and do some denoising which gets me a decent result. I also often have to raise mid-tones as well. My histogram normally goes up on the left in the shadows and mid tones and goes down in the highlights area. Wanted to ask you for your opinion on this.
Thanks in advance, Mike.
In any photo or video you need to be careful at underexpose or overexpose.
Remember that your eyes have a DR superior to any camera...
Now...
In NORMAL mode, is pretty simple....you need to be careful at underexposure, as the tendency is to underexpose an image and get improper crushed shadows. So you watch the histogram but pay attention at left of it, in darks part.
Also remember to "see" what you have as image and what is on histo...if you have darks in picture, close to black, set AF/AP/SS in order to have that blacks in left part of histogram, darker tones seen in reality by your eyes meaning histo on left, but careful. A good start would be to overexpose a little, see how histogram looks (you can see the spikes of darks and whites containing info), then use the scroll wheel on right of new RC to lower the SS until histogram is aligned to left, but without getting the "spike" of data over the left wall of histogram, as you will loose the shadow details.
In LOG mode, the sensor will increase the tonality of darks, so you will not be worried so much about shadows, but about highlights, as they increase too and will go from Highlight to Specular (loosing details)...This is why the process is reversed....you need to under-expose in order to see where is the spike of data on highlights, than slowly increase the light (modify SS/ISO as needed) but without crushing the highlights data in the RIGHT wall of histogram, as that is overexposing.
Also if do not use a LUT , you need to make at begining (in Resolve for example) some adjustments:
1. Recalibrate WB
2. Recalibrate the Blacks and Whites by using the curve line (move black point to White until where you see the Spike of data begin, move the White point on left until spike of white data ends...- if is needed, will make a small tutorial, but I think are many tutorials already on youtube on how to edit LOG without Lut), so will not go into many details.
3. Work with contrast by using curves editing, then edit colors as you like.
4. Need to say that DeNOISE needs to be made BEFORE any other work, as if you do it after, your noise pattern will be wrong and denoise cannot process it correctly...so, if you have night footage, before you touch any buttons, just denoise it.
Now...D-Cinelike...that is a semi-pro semi-log...or a hybrid...how every one calls it, does not matter. What you need to pay attention here is the right part of histogram as highlight will be increased and you can easy overexpose...but...as the D-Cine curve is normal from black to lights and increasing from lights to specular (non linear curve), you also need to be careful not to crush the blacks.
Editing is like LOG profile, but simpler, as D-Cine is pretty close to Normal profile but with 10bit color profile...(I made a 3D LUT for MIni 3 D-Cine for free, posted in this Forum).
Remember all time that your eyes have larger Dynamic Range than any camera, also the display you look at when you record or make pictures is influenced by the nits that is capable, by the light of environment, sun, and so on....so histogram is your best friend...Try to learn how to "see" the image in front of you as a histogram, where is the spike of Darks and the spike of Whites...
I give you two examples from random free images from internet...One was made with alignment of darks on left, as you can see the Shadows have all info needed in order to compose it nicely, the other one needed alignment on the right as the image have a majority of info on light-highlight-specular and could go very easy overexposed... Both are nice calibrated and well balanced from gamma point of view.
Imagine you will look the histogram on each of this 2 pictures, upload it in Lightroom or any other program and see if you get it right....
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