Beamshots - How are you doing yours?

[MSI]

This poll is to get a picture (pun not intended) of what camera setup people use to do their beamshots. If you select 'DSLR' or 'Compact with full manual settings', then it is assumed you use the same settings for all shots, if that is not the case then please select 'Compact camera using automatic settings' or 'Other' instead.

Taking good beamshots is not an easy task, and if not done properly can be more deceiving than helpul, something there is a lot of examples on here on CPF. The bad thing is that many people doesn't know when the beamshots are not good enough. I have seen beamshots that have looked like they were taken with a cell phone camera and people still managed to compliment the poster for the beamshots (I guess this is because of the friendly atmosphere here at CPF). However, what I find most annoying is powerful lights shone very close to a white wall and where the picture is highly over exposed, those pictures are just a waste of bandwidth. I may have sounded a little negative so far so I must add that there are also many examples of very good beamshots posted on CPF.

A good thread about the subject can be read here, and examples on how good beamshots can/should be done can be found in JS' A2 review.

I hope this post helps bump the awareness regarding doing beamshots properly.

 

[PlayboyJoeShmoe]

The only Digital camera I have available is a SEVERAL year old Sony MVC-FD90 Floppy Drive witha whopping 1.6 Megapixels!!!

It doesn't have a lot I can do. So I use moonmode. Usually with the lights all shining at the same wall from the same distance.

You'll also notice I don't post a LOT of pics because of this camera!!!

Here is one now:

You may notice it ain't great, but DOES show three lights compared to one another... they being River Rock 2AAA upper left, Inova Radiant 2AAA upper right and NiteIze Minim*g dropin bottom center.

 

[MSI]

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[OldNick]

I read the thread, which is unfortunately a bit olkd to start posting to, I thought. (??)

However I am interested in this, as I have just started to try to use beam shots, for comparison.

I immediately came up against standardisation problems; what camera settings do you use if manual? I posted a picture that I thought looked about "realistic" for beam strength, looking at the actual scene and bracketing the shot between 1/4 and 4 seconds.. It was taken at f2.8, 100ASA and 1 second. Another guy posted some pics (different light etc) and said his "realistic" was f2.8, _200_ASA and _3_ seconds. His shots of course made his light look a lot brighter than my (theoretically brighter) one, with 6 times the exposure. I did not believe his shots, in short.

I tried to confer, but was not getting straight replies. This is not to say I was not getting agreement. I was not even getting answers that addressed what I was trying to say. In the end I got frustrated and gave up in a huff.

The thread you refer to started to deal with this, but did not resolve it.

I think there is no question. All shots must be taken at an agreed exposure setup, of an agreed target (shapes, colours etc), at an agreed distance, or they are a waste of time for comparison purposes. Automatic cameras would be of interest, but little use for comparison.

The hard paret seems to me, once you have everybody agreeing that there should _be_ a standard, is to get them to agree what that should be. I feel this is important, as otherwise we are all send ing misleading shots, no matter how standard. People's perception of a scene can vary enormously.

The other suggestion was that everybody agrees to post a picture of a standard light source onto the same target. This means we have to then agree to and have that source.

 

[DFiorentino]

:wave: Welcome to CPF OldNick.

I'll chime in here on a few things I have noticed. Using a 'standard' camera setting can be detrimental for a couple of reasons. For one, differences in camera equipment as well as locale (ambient light levels, reflective surfaces, etc.) can vary and therby skew the final product. If this standardization is done to represent what one actually perceives with the human eye, it should be known that the eye adjusts for varying light levels. Such that a pic setup for a certain beamshot, let's say a lower lumen light, could be severly overexposed and misrepresented when compared to a higher lumen light taken at the same camera settings. In addition, eveyones eyes tend to see things differently. What I normally do (if I remember) is to set up my camera, starting with the highest output light, to give the best compramise between realism and detail. Those camera setting will remain for the rest of the shots at that time. It's usually easier to tell differences with underexposed photos as opposed to overexposed.

One peeve I have is the plain white wall shot. I think this type of shot is good for telling beam profile, but little else. It doesn't really show the the useful depth or width of a light's beam. Bernie (Kiessling) takes some great, very useful, indoor shots. ( :goodjob: )

Of course, these are just my opinions.

-DF

 

[abvidledUK]

Olympus C4000 compact(ish) using slow shutter flash 1.

This exposes for background, and uses fill in flash for foreground.

Useful for portraits outdoors, also allows torch beam to be seen, along with torch body indoors.

Sometimes, just auto, no flash, with daylight in through window, if this works better.

I always PS7 pics, to highlight what I want.

 

[PlayboyJoeShmoe]

When shooting a picture of a single beam there can NEVER be a reference standard!

That's why there are always at least two lights depicted in my pictures unless I'm trying to just show an awful beam like this:

or this:

And I try to use a known light as one when more than one are depicted

 

[OldNick]

Surely some agreed figure is better than purely subjective opinion of what is "real" when comparing lights that are not as different as a 100Watt spotty to a LED torch?

If we are comparing power LED torches, or even HID lights with LEDs, if we know the claimed Lm, and the angle of the beam, we can assume certain closeness or complete difference in light amoutn and maybe allow for changing iris size in the eye _if needed_.

Then there is the brain's reaction to light. It will probably "look for more" if starved. It will certainly want a photo to show more than a straining LED torch is giving.

Standard targets can be anything from white to coloured paper on card at a known distance from the light, with bits spread sideways to give beam spread. A piece of printer paper has pretty standard reflectivity within the range that we really need.

I am not looking for pinpoint here. As I said, I was having a difference of 6-8 f-stops in overall exposure, between myself and another poster, but claiming we had the "real" photos. I went out and had another go at the same target and came up with 1 second instead of 1/2 second. But I remember commenting when I posted the 1/2 second shots that they may have been a little dim. I jump from 1/2 to 1 in my camera.

Ok. I was talking camera setting standards.

Surely there _can_ be a reference standard comparison light, as distinct from camera settings. But we all have to have one, and we all have to agree what it is. And we have to have it at the right distance etc.

The other idea is to use the camera _on auto_ (or a light meter) to actually stand a given (standard) distance away from the LED, and take photos at on-beam, 5 deg off 10 deg off or whatever. Then when we look a the shots, using the figures we can see what is BS. Camera variations under normal usable camera standards should be within an f-Stop. Again better than the 6-8 f-stop equivalent disparity I came up against.

Once you have established how _really_ standard bright the torch etc is, you can snap away at leisure, with whatever settings (still not my preference). But each of the others can then judge your "free" shots by comparison with other stuff they have seen, where they know the actual figures.

If this "just won't work" at all, then comparison shots, except to show rotten beams <G> or beam spread, as very questionable.

When shooting a picture of a single beam there can NEVER be a reference standard!

That's why there are always at least two lights depicted in my pictures unless 'm trying to just show an awful beam like this:


or this:

And I try to use a known light as one when more than one are depicted

 

[OldNick]

See my other post. Unless the lights are _really_ different, the eye iris will not change that much. Not as much, in my opinion, as the brain itself and what it interprets _for the same light setup_ shown to two people!

While we may need overexposed shots to get a good idea of how the beam spreads in "real life" there also needs to be an agreed actual level of exposure to compare brightness at peak. I can quite easily make my lights go from complete darkness to daylight using exposures.

Ambient light levels could be a problem. Happy to work indoors for the test shots, with doors and curtains shut at night, and lights off.

I wanted standard target colour(s), sizes, material and distances to overcome reflection etc.

I actually tried using a grey-blue shirt on the line last night, against foliage. It made a good target for judgment of what was "real", for me. But I came out with the same exposure (f2.8, 100ISO, 35mm equiv lens, 1 second), even though the shirt was closer and brighter than the background shot I had used before.

My wife will be testing it tonight. It will be interesting to see.

But then I agree on the white walls <G>. We have to have a more interesting, informative (but standard target)

I reckon a shot in a good dark garden, against foliage, with targets in front, is the way to go. This gives a standard, but also shows what user wants to see.

:wave: Welcome to CPF OldNick.

I'll chime in here on a few things I have noticed. Using a 'standard' camera setting can be detrimental for a couple of reasons. For one, differences in camera equipment as well as locale (ambient light levels, reflective surfaces, etc.) can vary and therby skew the final product.

snip

One peeve I have is the plain white wall shot. I think this type of shot is good for telling beam profile, but little else. It doesn't really show the the useful depth or width of a light's beam. Bernie (Kiessling) takes some great, very useful, indoor shots. ( :goodjob: )

Of course, these are just my opinions.

-DF