Maus' Photography Tutorials VIII - JPEG vs RAW vs HDR

MadamMauMau submitted a new tutorial:

Maus' Photography Tutorials VIII - JPEG vs RAW vs HDR

Read more about this tutorial here...

 

HDR

Purpose: To produce an image that captures all the detail that the human eye can see.

How it does it: By taking multiple exposures of the same scene and merging them, it retains the details that would otherwise be lost in the shadows and highlights.

Advantages: By retaining all this detail, you will have a greater range of tonal values and than you would from a one-shot JPEG. This makes the image look richer, more precise and crisper.

Disadvantages: Introduces a couple more processing steps to your workflow.

Method:

• Photoshop is optimised to produce HDR using RAW files, so it is best to take your pictures in RAW. However this is not essential. JPEGs still produce a good result.
• Use a tripod and remote shutter release cable to make sure you camera is absolutely stable and your multple images are therefore pin sharp and align perfectly with eachother.
• You want your images to be as similar as possible, bar the required changes in exposure. This means you need to set as many of the settings as you can youself, and not allow the camera to make random decisions on your behalf. So, set your exposure on full manual mode, if you are brave enough. If you are not brave enough for full manual (I am not yet. Next step) use aperture priority. Use custom white balance or one of the presets, not auto WB. Again, this is to make sure your white balance is the same across all images. Use manual focus, not auto. If you have to use autofocus (I do, my eyesight is that bad), press the shutter halfway down to focus on the scene then, whilst the button is still halfway down, click the lens switch to manual to retain that focus.
• Take the shots. If you have it, use the "auto-bracketing" function on your camera. On my old EOS, it is in Menu, Option 2, AEB, click on it and then press the right select button three times to give a one stop difference and six times to get a two stop difference. Press the shutter three times. This will take three photos with varying exposures. It won't allow you to take any more than this, or to reduce or increase the exposure any more than two stops. It is a simple way of doing it, but it is limited.
• For greater flexibility, use aperture priority and use exposure compensation facility on your camera to lower and raise the EV (exposure value) to give a greater number of exposures. The number of exposures should always be an odd number so that there are an equal number of adjusted exposures either side of the “normal” one.
• Merge the photos in Photoshop. Go to File > Automate > Merge to HDR and a dialogue box will pop up, asking you to select the photos you want to merge. Click Browse and add each photo in turn or press shift to select all at the same time. Press OK to merge and save the combined image. It won’t look right, but this is because your monitor just can’t handle the range of tones in this image. Adjusting the white point preview makes changes to how you see the image but won’t alter the actual HDR.
• You then have a limited number of adjustments you can make with this large, rich 32-bit file. It is a good idea to do at least some of these adjustments at this stage, before you have to reduce the size of the file and lose some of that data. The most important adjustment is to set the white and black points and the mid tone. There are two ways in which you can do this.
• The first method is by going to Image -> Exposure and sliding the exposure slider to the point at which the first pure whites appear (setting the white point), the Offset slider to set the point at which the first dense shadows appear (the black point) and the Gamma to tweak the midtones. Unlike with the RAW processor, you won’t get that helpful little failsafe of watching for your red and yellow patches when you clip the white and black points. This one has to be done by eye (at least on my ancient copy of Photoshop).
• The alternative method is part of the stage of converting the file into a more manageable size. To do anything with the file, you will need to reduce it down from its current impressive 32 bits so that Photoshop can handle it. Go to Image -> Mode -> 8 Bits/Channel and that will shrink it right down.
• You will now have some options in a drop down menu for making adjustments. If you already made your adjustments using the Exposure sliders, just click OK to save. If you are most comfortable using a toning curve (which comes up with the “Exposure and Gamma” option), however, this might be the better option for you. Alternatively, you can set the white point and adjust the midtones with the exposure and gamma sliders.
• Click OK to save and you will now be able to use all the usual functions on Photoshop on your combined image.

 

HDR vs RAW vs JPEG

Let the battle commence.

All images are unprocessed, except a little tweaking on levels to get them to look like approximately the same lights and darks, so that they would be easier to compare.

Normal jpeg.



RAW



HDR



Comparison of details



Comparison of shots overall.



Conclusion? It is difficult to draw one as all files had to be compressed to jpegs, as this is what I use for online posting, so this would reduce many of the differences. Also, I didn't do much post-processing, such as burning and dodging, which would again have really showed the benefits of a large, detailed file, such as the HDR. Lastly, although I am too modest to say so, it was a competent initial photograph, so not much in the way of wonky exposure or colour balance to correct for, which would have given the RAW process a useful outing.

Compared to HDR and RAW, the JPEG does look pretty "jammy" and crude, lacking in sharpness and detail. Between the HDR and the RAW, my money goes on the RAW. This is largely because of the failsafes in the convertor when adjusting exposure. This stops me from performing my usual tendency of raising the white point so far that I blow out highlights. HDR also seems to produce cool, grey shadows, which could be adjusted, but I would rather not have to.

I would be very interested to see any one else's experiments with this and any other hints and tips on working with RAW and HDR.

I hope this was useful and not too mind-numbingly technical and geekish. Yeah, OK. I know it was, but hopefully you found a way around it.

 

Do! It takes a bit of faff to get started, but is well worth it.

 

I think most do these days, but few use it.

If people are starting with this, let me know progress on here. I had many a false start when I got going and had a good friend standing by to give moral support and listen to me swearing. It helped me keep pushing on. So, if you are encountering obstacles and having problems, post them on here. They might be ones that I have already found a way around, or we might be able to figure them out together. Either way, two heads are almost certainly better than one.

 

Those are beautiful, crisp images, well-balanced, and I think they really show the potential of RAW. As JPEGS, they would be good, but would probably lack that depth of detail. THanks so much for posting those. If you have any discoveries you have made with either RAW or JPEG, do post here.

And the value of RAW for those images above is if you are going to do more editing to them than I did there. So, dogding and burning and other bits of tweaking for a final, edited version, using the RAW image. You have more to play with starting from a raw file than a JPEG.

 

Great to hear you are getting to grips with it. What is really good is those failsafes in the editor. It really takes no time at all to get perfect exposure.

Yes, RAW editing on my tiny little old netbook makes it crawl along after a few shots. Another downside is that it eats your camera battery, so always have a spare.