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Technical question concerning Digital photography

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Doctor_Occupant

Gone But Not Forgotten
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I recently got my hands on a digital picture from a local ghost-hunting group's investigation that they say shows some anomalies.

I think I've managed to debunk a couple of things, but I have a question: can digital cameras take 'long exposure' type photos?

I can't link to the picture from here - for one thing, I'd need to ask permission from the owner - but I can give a general description of the effect I'm concerned about.

The picture is of a hotel room. We can see a ceiling lamp, a laptop and a TV. Each of these is on, and the light from each appears to be cascading out and down, in front of the source object.
- I'm really going to have to link to this, aren't I? I'll see if I'll be allowed to.

Meantime, the effect I'm seeing is rather similar to this:
oly8sec320.jpg


Can a Digital camera - make and model unknown at this time - produce this sort of effect?
 
Anything you can do with a 35mm film SLR, you can do with a digital SLR, a 1 second or so exposure like this would be simple with a SLR. The compact style digital cameras (that most of us own) generally cant do this (as generally cant the compact 35mm film ones), its the fixed shutter speed or aperture you see, a SLR has variable shutter speeds (going to seconds rather than milli-seconds) and a variable aperture, going very low (or high, depending if you consider f22 high or low lol)!

Some webcams can be manipulated for effects pretty well though, and are pretty cheap too, we produced interesting effects with a webcam youd normally need photoshop or an expensive SLR to do, but webcams are pretty lo-res.

hope this helps!

>edit - typo and word missing :)
 
Presumably you can alter the shutter speed on a digtial camera (or enable it to simulate a slower exposure)?
 
It's certainly possible for a digital photograph to be blurred if the camera or subject is moved while the photograph is being taken, the same as any other camera.

It rather depends on the sophistication of the camera whether the 'shutter speed' can be altered either manually or automatically depending on light levels.

I certainly have taken pictures with a cheap digital camera in low light conditions and moved the camera resulting in 'trails' from lights etc.
 
_Lizard23_ said:
It's certainly possible for a digital photograph to be blurred if the camera or subject is moved while the photograph is being taken, the same as any other camera.
Click to expand...

AFAIK, the camera in question is a compact digital job. The picture itself is fairly clear and only the lamp, TV screen and laptop screen show signs of motion blur. If the camera was moving, wouldn't everything be blurred?
 
Doctor_Occupant said:
AFAIK, the camera in question is a compact digital job. The picture itself is fairly clear and only the lamp, TV screen and laptop screen show signs of motion blur. If the camera was moving, wouldn't everything be blurred?
Click to expand...

if the camera is moving at the same speed as the item you are photographing, the the background will be blurred and the moving item sharp (like photographing a sports car).

many clever effects can be created without filters and before photoshop!
 
you can also have some items more blurred than others, or blurred in another direction to the rest by "panning". if you can share the pic with us it may help" :)
 
The picture itself is fairly clear and only the lamp, TV screen and laptop screen show signs of motion blur. If the camera was moving, wouldn't everything be blurred?
Click to expand...
In the long exposure photo you showed above though there are no cars, just the lights - the cars are moving too fast to show up as anything except a very very faint bit of blurring but the lights are shown as a continuous strip because they are much brighter - could this not be the case with your hotel room pic also? You do say it is only 'fairly clear' - if the camera were held still long enough to photograph the stationary objects and then moved very rapidly the different positions of the objects might be invisible, like the cars, but the light trail would show, perhaps.
 
Thanks for the comments so far, folks, you've all been really helpful.

I'm going to ask for the OK to host and post the photo in question and (fingers crossed) we'll see what you make of the image itself. :D
 
Additionally, if the camera is twisted slightly whilst being moved you will also get a different point of focus and some itms in it will appear more blurred than others.
 
Even with a basic digital camera, if you chose to take a photo on an interior without using the flash, movement can sometimes come out blurred. Somtimes only a small amount of vibration will blur stronger light sources in the photo, without the image looking blurred elsewhere (there may still be blurring across the image, but this would be harder to spot if the image is of a lower resolution).
 
If you take a long-exposure picture, but still use the flash, and there is some shaking (deliberate or otherwise) of the camera, then the areas in, say, a darkened room, which are only illuminated by the flash will not be blurred, but light sources which were visible outside the time of the flash will be.

Does that make any sense? I've read it back, and it's not quite as clear as I'd like. Too many commas!
 
Oh-kay.

I've been told that no, I may not post the original picture. On that basis alone, I'm tempted to call Shennanigens.

Instead, in the tradition of Crimewatch, I've got a reconstruction here.

I want to emphasise: This is NOT the original image, this was produced by ME with Paintshop Pro but sadly it's the only way I can show you approximately the effect on the original without making the picture owner angry with me.

laptoprecompositeeb3.jpg


On the original image, the wallpaper is a word in bright blue that has blurred and appears to be leaking out over the keyboard. On the original, the blurred image appears to touch the keyboard itself or end in front of it.

As with the above mock-up, the laptop itself is pretty crisp and clear and shows none of the blurring that the screen image shows.

As I said, this is an approximation of the original. I will continue to seek permission to post the photo itself, or elements of it (since it's about 3mb in size) and if the owner posts it on a website I'll link to it.

So. The question once more: Would it be possible to reproduce the above using a compact digital camera and motion?
 
On the info given so far, I think Peripart is right. If flash was used, that would give a clear image of things during the (extremely brief) flash period.

However, the shutter is generally open for a longer period, giving the possibility of bright objects blurring if the camera is moved during this time. Are all the blurs consistent with a single camera movement (ie, translation plus rotation?)

So, was flash used?
 
Anybody got any ideas how I managed to do this with an SLR digital camera, because I'd love to be able to do it again and have no idea how I managed it.

link


(very long link tidied up - stu)
 
HelzAngel said:
Anybody got any ideas how I managed to do this?
Click to expand...
Looks like a fairly straightforward case of double exposure, where for whatever reason the film has not wound on properly betwen shots. On some SLRs, you have the ability to do this intentionally - just as often, though, it happens accidentally.
 
rynner said:
On the info given so far, I think Peripart is right. If flash was used, that would give a clear image of things during the (extremely brief) flash period.

So, was flash used?
Click to expand...

I believe so. The light levels in the room were such that if the camera had been left to its own devices, it would have used a flash. The problem, and one of the reasons the pictures have caused the owner to be fairly excited, is that no one took the photos. There is a series of three pictures, two of which show two of the three people in the room asleep. All three people insist that the pictures were taken when they were all asleep but one of them was on the floor, in a position where they are occluded by the bed.
 
Peripart said:
HelzAngel said:
Anybody got any ideas how I managed to do this?
Click to expand...
Looks like a fairly straightforward case of double exposure, where for whatever reason the film has not wound on properly betwen shots. On some SLRs, you have the ability to do this intentionally - just as often, though, it happens accidentally.
Click to expand...

Sorry, should have said before, it was on a digital SLR (Nikon D50)
 
Still just looks like a double exposure, even if no actual film is involved. Somehow, one image file has simply overlaid the other but, not knowing the ins and outs of digital photography, I couldn't hazard a guess as to what has caused this to happen in this case.
 
its very easy to produce that sort of image. You import one image into Photoshop, get the second, increase the transparency and lay it over the top of the first.

et voila.
 
Agreed, but HelzAngel has said that this has happened by accident, which is beyond my expertise (doesn't take much, TBH). Pretty sure the explanation isn't supernatural, all the same.
 
I take on board what you say but I'm not sure I'm convinced. A digital camera has a sensitive chip called a CCD (Charged Coupled Device) which in basic terms transfers the light entering the lens into the picture that you eventually see.

If the camera, media card or CCD has malfunctioned in someway, e.g the card had not written the image correctly, there is usually a blank frame instead of the digital camera showing the erroneous picture.

I'm not professing to be an all knowing guru when it comes to photography. However I have used enough budget and pro digital photographic equiptment in my time, and, IMO it would be almost impossible to achieve that affect without editing the image in some way.
 
id like to politely suggest that everyone with questions has a look at a digital photography site, all your Qs and more will be answered and like me, youll probably lean something too!

as to the reconstruction, its taken in low light, there is a flash hotspot along with a reflective object moving, not hard to reproduce. and yes the fact they wont let you show it here means they dont want ppl to say how its achieved, not that its a mystery. theyll be proud of some "orb" pictures they take next :)
 
RealPaZZa, I did as you suggested and yes, a few questions were answered but I actually found my best information in the False Positives part of the TAPS forum.

Someone there had almost exactly the same issue and the cause was described very clearly.

Now, the only mystery that remains is to find out who took the photos when the three people in the room were all asleep.
 
or in true faker style - they are telling porkies about how/when it was taken!
 
RealPaZZa said:
or in true faker style - they are telling porkies about how/when it was taken!
Click to expand...

That's the obvious answer. They do insist that everyone was asleep but there are elements to the story that don't make sense to me.

Rather than recount it all here, let's just say that when an alternative explanation was put forward one of the investigators said that if someone had been moving around he'd have heard it and that it couldn't have been anyone from outside the room because the doors are really heavy and he'd have heard it close.

When I cry shennanigens, the response is "You weren't there".

So. Onward.
 
imho we can terminate our enquiry and agree we can all fake better with a more convincing story!
 
Doctor_Occupant said:
I recently got my hands on a digital picture from a local ghost-hunting group's investigation that they say shows some anomalies.
Click to expand...

Which group was it?
 
Peripart said:
Agreed, but HelzAngel has said that this has happened by accident, which is beyond my expertise (doesn't take much, TBH). Pretty sure the explanation isn't supernatural, all the same.
Click to expand...

I think I'll just go for the option of not using my SLR digital after more than a bottle of wine, then I might be able to remember how to use it.

id like to politely suggest that everyone with questions has a look at a digital photography site, all your Qs and more will be answered and like me, youll probably lean something too!
Click to expand...

and I'd like to politely suggest that if you're not interested in a thread titled "Technical question concerning digital photography" you read a different thread.

There is no reason why people shouldn't discuss the possibilities of the construction of supposedlty supernatural photographs, the original question was regarding a photograph from a ghost hunting group and the link I posted was just an example of how these things can be created by accident.
 
The 2nd quote, although nameless, is mine. I am VERY interested in this thread, that is why im part of it. im not very interested on many of the other threads i havent joined in with (although I am a few of them), sounds pretty logical if you think about it!

Doctor_Occupant, who started the thread seems genuinely interested in how it can be a photographic "accident", a mis-interpritation or perhaps a fake. I am VERY interested in photographic fakes and why believers in the unprovable will use fakes to try to substantiate their belief!

and i thought we where discussing how the photograph was constructed! im as entitled as you are to join this debate. Its not rocket science is it? ;)
 
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