green laser versus photography?

[wavelandscott]

I've read of observing nights that have banned the use of green lasers due to the claim that they are harmful to imagers...Is this really true?

While I can think of a number of "safety" reasons to restrict (maybe ban) the use of green laser pointers I have not seen any evidence myself that they are harmful to imagers...I have not looked for evidence and I am not an imager so I don't know but I am curious.

So, do green lasers interfere with imaging? Can anyone show me a "ruined" image to support the assertion that green lasers are harmful?

Not looking to start a battle royale just curious...last night at the RPS/NSAS Viewing night a green laser would have been handy to point out some things to people but I understand that some observing organizations are opposed to them...that is why I am asking.

In the interest of full disclosure, I do not currently own a green laser pointer and have no immediate plans to buy one...(but, my birthday is coming up ;) )

[[1ponders]]

Let the experiments begin. :)

Well it barely shows any interference with the SAC 4.2. Yes if I shone the laser on the wall I certainly picked it up :P but move it outside the field of view and it wasn't noticeable. Next I shone the beam directly across the front of the objective and then waved it slowly up and down. At an exposure of 2 sec it showed barely an increase in light levels. Even when I bounced it off the inside of the dewshield of the ED80 there was hardly a murmur.

Now this was indoors, and with nothing reflecting in the beam. I'll try it outside next night I am able to get outside.

So far: laser 1, imager 0

Maybe someone will do a DSLR next.

[OneOfOne]

About 2 months ago, I was playing around with taking some shots on a tripod using my Panasonic compact. I also had my scope set up and pointing at Alpha Centauri, with my 5mW laser on. In a exposure of 60 seconds, at 100ASA, I could clearly see this green light pointing from out of the frame and up to Alpha. So I would say that based on this, taking an image in the same direction as a "static" pointer could quite easily ruin an image....whether it does anything to the imager is another matter, but if it was me that had just spent a period setting up for a shot only to find that many of the frames are ruined by someones pointer, I would not be happy (Jan).

However, as for claims of damaging the imager....unless you point it directly at it, I doubt it would do anything...otherwise, I would expect a lot more damage from pointing it at the Moon!

The main problem with using lasers at a dark site is that it may very well upset peoples night adaption. This alone is enough that I only use my laser for initial setup and then turn it off and leave it off. If you were viewing from the 'burbs, I doubt your dark adaption would even be effected that much by turning on a mobile phone.

[wavelandscott]

When I used the phrase "harmful to imagers" I was trying to enquire about ruining the image or picture itself and not the equipment.

I appreciate your reply and observation...do you still have the image?

Thanks!

[ving]

interesting scott... its a case of laser showing newbies thing vs imager.... i think the laser has it place now and it would be hard to stop people from using them.

[[1ponders]]

There is a blanket ban on them at Qld astrofest. We were fortunate/unfortunate enough on the Saturday night after the feast to have a light shower come through and everyone covered their scopes and ran for the port. After that no-one was interested in imaging, but there was some god awful singing going on :scared: After the shower passed we hit the lasers :)

[TidaLpHasE]

I took this pic this morning showing something green in the frame:shrug:

ISO 1600 30 second exposure f/5.6 70-300mm @300mm

It is right under the camera lens and i turned it on and off a couple of times, but i would think that it will ruin an image even at a distance if it crosses the imaging path enough times or stays within it for long enough.

So it definately shows up and would be a problem if people are waving these things around all over the place while others are trying to image.

[[1ponders]]

Cool shot Trevor. "The Road to Infinity"

Well I'm convinced.

[TidaLpHasE]

:)I should have tried writing my name:P

This was with the modded camera, so sensitivity might be more so than an unmoded one:shrug:

The brightest parts to the bottom is due to a light layer of fog, as the pointer clears the fog, it reduces in brightness, so at the top where it is faded would be a normal view of it i would think, still enough to effect an image.

[bloodhound31]

That.....is a very nice shot mate! George Lucas could have saved himself a fortune in the 70's before ILM came along.

I have a green laser pionter myself and I have found it an invaluable tool when trying to describe constellations to the uninitiated. It saves you so much time and people saying, "Where?, Whats he pointing at? No, I can't see it!"

Instead you get, "OH YEAH NOW I KNOW WHAT IT LOOKS LIKE!"

and in a fraction of the time...

I love my laser!

Baz:D

http://members.iinet.net.au/~armstead

[ving]

what!
you can see stars thru it, whats ya problem? :P

if kyou were say 10-15 meters away waving it around do you think it would have made a difference? (as opposed to having it right under the camera)

[cahullian]

Not to stir things up...but why should people imaging infringe on those who love their pointers? Is it because imagers may spend more on their hobby?? What's next the SCT owners getting prime location spots at sites over Dobs??
Where will it all end? Will it ever end??

Sorry me bad:astron: :fight: I was here first...get that laser out of my face:argue: He he he

Gazz

[wavelandscott]

Thanks for that picture!

I'm not sure about how the "property rights issue" should play out concerning the laserers v imagerers...both groups would seem to have a legitimate claim for rightful use of the resource (in this case the nightsky)...

In many ways this issue is like having a house with a view until your neighbour builds an extension/adds a level and blocks your view...allocating a scarce resources is always tricky...

Anyway, I got an answer/proof that I was interested in seeing...it seems that green lasers can be picked up by imaging equipment and at least have the potential to interfere with a shot...I am sure that there are/will be some boundaries around this (duration, intensity etc.) but I see that if "can" happen...

Thanks!

[rogerg]

I know lasers can appear in long exposure photo's, but to be honest I don't care about them much at all when I'm doing my photography (and that's all I do, barely ever visual).

People at the events I go to are often paranoid about asking me if it's ok, if I'm taking photo's, etc. With respect to light and lasers. Well it really doesn't matter these days. Usually the FOV I'm shooting is narrow enough for the chance of an "impact" to be very slim, and even then, if I do get one frame with a laser in it, so what, it's digital, I am going to take 20 frames anyway and so will just exclude that one.

If someone from 20m away uses one the chances of it making an impact on your image are very slim, as compared to holding one in line with your telescope. Just like it's harder to see someone's who is 20m away and you're looking at it side-on.

I figure that they are so beneficial, and others enjoy using them, that it's not worth being nasty about them or inconveniencing anyone else to ask them to turn them off, because it doesn't inconvenience me at all.

I would be very anoyed if they were banned at the events I go to, simply because I rely on using mine for pointing (don't have a telrad or finderscope) and polar alignment. I'd have to buy a polar scope and a finderscope if they were banned, that's $400 I'd rather not spend.

Roger.

[OneOfOne]

Maybe ban GoTo's because they only want "real" astronomers? Only manual mounts because the electric motors make too much noise? Only scopes over a certain size because only "serious" scopes are allowed? No computers because of the light pollution from the screen? Only film cameras because cables are a tripping hazard? No children because the might "touch something"?