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jetset
2005-Dec-27, 10:31 AM
Hi people, I'm no astronomer or photographer but decided to take my 300D out into the garden last night.
I saw this orangy/red star and thought it maybe Mars, zoomed to 300mm, and this was the result.

http://www.btinternet.com/~sph70/Mars_800.jpg

Cropped

http://www.btinternet.com/~sph70/Mars_crop.jpg

origional image 3072 x 2048 http://www.btinternet.com/~sph70/Mars_.JPG

Can anyone tell me what I'm seeing here..?
Is it camera related, or have I caught something orbiting a planet..?

Thanks in advance

Steve

ryanmercer
2005-Dec-27, 01:35 PM
Hrmm... no tripod I see... that is quite odd, thats not anything orbiting, nothing would have an orbit that insane or fast... thats just your unsteady hands + time delay = that.

suntrack2
2005-Dec-27, 04:57 PM
don't leave "try", try try and try you will get success to catch the object in the film, jetset. you have tried better to get the image.

thanks.

jetset
2005-Dec-27, 06:42 PM
Thanks for the replies...

I did use a tripod, it was a 15-20 sec exposure so I think the effects would have been much worse if I had hand held it..:D

Thanks again

Steve

NEOWatcher
2005-Dec-27, 06:49 PM
Thanks for the replies...

I did use a tripod, it was a 15-20 sec exposure so I think the effects would have been much worse if I had hand held it..:D

Your tripod's not stable enough for that shot. Here's how I interpret what happened.
The wide line (NW to SE) is the path that Mars moved during the exposures. The narrow line (starting at what looks to be an outer orbit) is where the shutter first opened and the tripod was most wobbly. Note that the paths of this line seem to be centered around the "start" of the wide line path. As the tripod "settled down", the narrow line got closer and closer to where the remaining wide line is.

tony873004
2005-Dec-27, 08:01 PM
Try it again, but during the middle and end of your exposure, tap the tripod and see if you end up with more "orbiting objects".

To get rid of the effect use the camera's autotimer so your finger is not on the camera during the beginning of the exposure.

jetset
2005-Dec-27, 11:35 PM
Ah ha...I wasn't using a remote release, so that's the reason

Thanks for your time tony873004 and NEOWatcher

Steve

ShevillWMathers
2005-Dec-28, 07:14 AM
It looks like Mars due to its colour and brightness and this is what has happened.

At a high tele magnification, earths rotation is causing the Stars & Mars to trail. 15 - 20 seconds exposure is far too long. If you repeat the shot and start at 1 second then increase the exposure for each successive shot i.e. 1, 2, 4, 8, 10, 15,20, 30 seconds, this experiment will clearly demonstrate the earths rotation effect. because the trails will get longer. St some stage the bright object will be a round dot.

The fainter lines are stars and the effect is less pronounced because it would need more exposure to show up but the squiggles would all have the same pattern.

The sqiggly lines are due to the camera/tripod being touched lightly during the exposure and what you see are the oscillations/vibrations produced. Remember at these sorts of tele shots even the slightest movement shows up.

Use a long cable release, don't knock the camera or triopod during exposure and keep out of the wind - if any.

Hopes this helps

Shevill Mathers, Southern Cross Observatory - Tasmania. www.taao.has.it

J. P. Morgan
2005-Dec-29, 03:45 PM
Google "Barndoor Tracker" and see what you find.

JP

Tog
2005-Dec-30, 07:01 AM
I has similar things happen when I was trying to take pics throught a meade ETX. With an SLR camera, the mirror that deflects the light up through the viewer will have to be lifted out of the path of the light so the film can see it. At the same time, the shutter will open. In my old Minolta, the shutter opens on one side, then the other side moves over to close it to give uniform light coverage to the film. Winding the camera resets the two shutter sections to the original position for the next shot.

When you take a picture with a long focal length, the mirror slap can create an up and down vibration, and the shutter movement can cause a left to right (rigt to left) one; though usually much smaller. I think you are getting a combination of the two.

The two easiest fixes are 1) Your camera may have a mirror lock up. This is a smal dial nea where the lens attatches that can me used to raie the mirror after you focus, thi will help to eliminate the mirror slap. 2) Top Hat photography. Get a large containe, like a coffee can and paint the inside flat black. place it over the lens of the camera without letting it touch. Open the shutter and wait for a few seconds. Remove the can and start the exposure. Place the can back over the lens and close the shutter. This will give the camera a chance to settle down before the light hits the film.

Keep at it. I have a whole drawer of pics that look like that, but when you get a good one, it's all worth it.;)

suntrack2
2006-Jan-01, 03:52 PM
practice makes man perfect!

mickal555
2006-Jan-01, 06:19 PM
Thanks for the replies...

I did use a tripod, it was a 15-20 sec exposure so I think the effects would have been much worse if I had hand held it..:D

Thanks again

Steve

Looks like it was steady for a bit and then got bumped or visa versa...

;)