Shooting Beamshots with HDR

clemence · 2019-08-19T08:05:23.000Z

It’s not easy to take realistic real world beam shots because our eyes are so sophisticated they have very wide dynamic range. Dynamic range is the range between the darkest image and the brightest image a camera sensor can capture without losing color data. Wider = better. Very few cameras can replicate human eyes dynamic range. We can see all the way from faintly lit to very bright objects in the same scene. Although we need some time to adjust our eyes between very high contrast scenes. Wide floody beam is so much easier to shoot than a throwy light with dim spill. Beam artifacts also hard to show in combo beam (flood - throw).

There are many ways to get good shots but this time I will weight more in the importance of creating a very high dynamic range beam shots which, hopefully, will help people easier to post and extract more useful data from beam shot posts.

There are many post processing software to choose for. I used DxO Optics Pro 10 (very slow!) for processing all my RAW to JPEG conversion until two months ago, I received a 50% discount coupon code for ACDSee Photo Studio Ultimate 2019. I always use ACDSee since 1997 to manage all my image collection but never tried its RAW converter until recently. It’s not the best software but I really like it because it has all I need in one package (converting - managing - editing) for all my photo collections with familiar UI.

For focus stacking I use simple and lightweight freeware program: Picolay

Use any HDR software you feel most convenient. Plenty of them available. Here are some good compilation list: Top 20 Best HDR Software Review 2023 | HDR Photography by Captain Kimo
http://hdreditingsoftware.com/
I use Photomatix Pro 6 because it’s relatively cheap for what you get ($99 Pro $39 Basic) and very easy to use. If you don’t mind with the “photomatix” watermark then you don’t have to pay for it. It’s fully functional forever.

Shooting

Tripod or any stabilizing method is very important. I always try to position my Camera as straight/parallel/center as possible with the center mark of screen/wall. A temporary cross hair aligned to you camera cross hair is very useful. I use masking tape with markers to aid in beam comparison. I should use white masking tape but all I found was yellow colored.

Use manual mode (shutter speed, aperture, and focus). For smartphones there are plenty of good camera applications with more manual control. turn off any filter or enhancement (soft, beauty, dramatic, etc…)

Shoot in RAW whenever possible. If your camera doesn’t have RAW option then use the finest picture quality (fine JPEG, no compression, etc…). RAW file has the most image data as seen by the sensor. With RAW files you can adjust the output to relatively the same when you later upgrade your camera or lenses.

Use your native camera resolution (no digital boost). Some camera has options for resolution and aspect ratio outside it’s designed set.

Use native ISO. Most camera designed to works best at ISO 100 - 400. Operating outside native ISO will create more noise especially if you’re shooting in RAW mode. Lower ISO usually gives you the widest dynamic range but not always
Photographic Dynamic Range versus ISO Setting

Use medium aperture to slightly widen the field of focus. Large aperture (small f number) will create very narrow field of focus. This is very important when you can’t find a straight level wall or shooting outdoor beam shots. The area outside focus will gets blurry and masked the CCT shift/tint shift/artifact you want to present in your shot.

Large aperture (small f number) gives the sharpest focus and narrowest depth of field
Small aperture (high f number) gives the widest depth of field but softer focus*
If you have the time and the flashlight you’re shooting capable of holding relatively the same output for extra shooting time then the best option is to take multiple shots with smallest aperture. Then use focus stacking software to make a merged fully focused image.

Set the WB to 5600K - 5800K (or “daylight” if I don’t have the option for manual WB) depending of your camera make and model. I stick to that value forever. This will be useful for future reference. Those WB numbers are the standard for correct daylight. In my opinion 5700K is the ideal value. My camera can only select either 5600K or 5800K, so I use 5600K and later adjust it to 5700K in RAW processing. Any beam shots with auto WB clouds the CCT/tint information especially in community like BLF. Below is the example of how loose auto WB can be. You can’t get solid ground for community sharing purpose with auto WB.

To get good HDR beam shots you need to do exposure bracketing. That is, take several pictures with different exposures from under exposed to over exposed. Keep the aperture setting untouched, change only the shutter speed. It will be very convenient to use “exposure warning” feature if your camera has it. First find the shutter speed setting with the most under exposed without the over exposed warning, then reduce the shutter speed all the way until you get no under exposed warning. Shoot several images in between those two extreme.

Processing Steps
Never over processed the image. Sometimes its easy to get carried away for a pretty beam shot that is totally different from what its supposed to look like. My usual steps are:

Geometry correction according to your camera body and lens make and model.
HDR processing
Focus stacking (if needed)
RAW to JPEG conversion (100% quality). Remember every time you convert your RAW file data to any compressed image format you’ll lost more data especially the color information required to get a hi resolution HDR image. Always try to do the conversion as the last process.
Auto level (contrast only). Since this step is usually optimized for compressed image format in most photo editor, I do it after the conversion.
Add caption & watermark
Downsize huge images to manageable upload/viewing size

The HDR processed result can be seen at the bottom right corner:
Armytek Dobermann Green XPE2

The result of a total of 22 stops, 11 images. Very realistic HDR image as seen by the eyes

Jetbeam Jet MKII Cree XPL HI

The result of a total of 22 stops, 11 images. Very realistic HDR image as seen by the eyes

HDR processing is not as simple as blending two or more images. The software use the color information from “correct” image to fill in the missing data in the clipped areas. It’s like recreating the whole new image using extra information.

UPDATE 190904: Another useful application using HDR and focus stacking technique (in context to BLF crowd)

Sometimes we have purposedly make unrealistic images for specific needs. I made some shots for this thread few days ago: Finally I beat Fenix FD40
In order to show Fenix FD40 many components, I shot all of them in exploded view from an angle. But to show each components in detail is impossible unless we use focus stacking technique. Even our eyes don’t have such wide depth of field at close distance. The flashlight components arranged in a straight line spanning at about 50cm from end to end. I made 17 shots in total

To better show the detail of the driver components I made two shots with additional directional lighting from each sides. Below are the result of HDR + focus stacking technique. The resulting image shows minimal shadowing wit sharp focus at desired board plane.

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[Clemence]

Relampago · 2019-08-19T08:37:26.000Z

Neat. I’ve been wondering about how best to capture beamshots and comparison photos of different tints.

Pavlo · 2019-08-19T14:48:37.000Z

I have always found most videos or beamshots of throat lights to not represent what we see in reality very well. Great post Clemence.

clemence · 2019-08-20T01:49:33.000Z

Pavlo:

I have always found most videos or beamshots of throat lights to not represent what we see in reality very well. Great post Clemence.

With your Sony AII, you can get waaaaay better result using less images. It has very good dynamic range by default.

[Clemence]

DavidEF · 2019-08-20T02:28:47.000Z

I’ve played around with HDR image processing in the past, but never got really good with it. This post gives me a lot of information I never knew. And I never even thought about HDR for beam shots! Thanks for taking the time to do this! It’s a very valuable resource for the BLF community.

twisted_raven · 2019-08-20T03:10:36.000Z

I’ve found shooting raw with my A6300 and bringing up shadows in lightroom to be good enough to what the eye sees. Problem is that when uploading to the net, the compression kills all the shadow details.

I don’t like HDR software, I rather use exposure masks in photoshop. I use that feature all the time for landscapes where I want to darken the exposure on the sky.

clemence · 2019-08-20T04:10:42.000Z

This technique might not be needed for those with high end camera. Very useful for me with my old Olympus EM5 with its limited dynamic range. But even a full frame usually still face the same problem shooting throwy beamshots.
What I really like with this technique is you still can compare between different flashlight brightness reliably. Just start from the brightest mode and keep all the setting and steps the same.

[Clemence]

zpinch · 2019-09-03T14:49:43.000Z

I have a Sony A58 camera, I have always used to the auto setting on the camera and have always produced subpar beamshots, always grainy and artifacts, to be expected when I shooting out to 1/2 mile I suppose.

I didn’t see any programs mentioned, so what would you suggest for free-to-use photo software to use?

clemence · 2019-09-03T14:55:15.000Z

zpinch:

I have a Sony A58 camera, I have always used to the auto setting on the camera and have always produced subpar beamshots, always grainy and artifacts, to be expected when I shooting out to 1/2 mile I suppose.

I didn’t see any programs mentioned, so what would you suggest for free-to-use photo software to use?

What programs? I did mention some

[Clemence]

manithree · 2019-09-03T15:19:37.000Z

Remember every time you convert your RAW file data to any compressed image format you’ll lost more data especially the color information required to get a hi resolution HDR image. Always try to do the conversion as the last process.

Good advice, but there are lots of lossless compression formats and your comment only applies to lossy compression (of which standard jpeg is one).

I’ve been meaning to play around with this. My Canon SLRs all run magic lantern and it has the option in exposure bracketing to write a script to get you started with enblend/enfuse But there are so many options I haven’t gotten the right combination of exposure and focus blending or tone mapping yet.

clemence · 2019-09-03T15:29:07.000Z

manithree:

Remember every time you convert your RAW file data to any compressed image format you’ll lost more data especially the color information required to get a hi resolution HDR image. Always try to do the conversion as the last process.

Good advice, but there are lots of lossless compression formats and your comment only applies to lossy compression (of which standard jpeg is one).

I’ve been meaning to play around with this. My Canon SLRs all run magic lantern and it has the option in exposure bracketing to write a script to get you started with enblend/enfuse But there are so many options I haven’t gotten the right combination of exposure and focus blending or tone mapping yet.

Yes, there are lots of them. Thanks for pointing that out. I use JPEG compression as its the most widely used and compatible with most softwares. But still, less RAW conversion to anything the better. And I also don’t have the luxury to use high end camera like yours, as many do around here.

[Clemence]

zpinch · 2019-09-03T15:36:21.000Z

Thanks. I see that now, I was must have skimmed over it.

clemence · 2019-09-03T18:43:27.000Z

OP updated
“UPDATE 190904: Another useful application using HDR and focus stacking technique (in context to BLF crowd)”

[Clemence]

ma_tumba · 2019-09-05T12:04:02.000Z

Great post, indeed