Is this right, 350D Question

[Shawn]

These are the sequence of images , 200 secs 5 secs between exposures, @ 800...

Anybody help me here as to how to minimise this...

Cheers All

S

[[1ponders]]

G'day Shawn. What is your image processing program?

If you have the Canon plug in for photoshop they will open in photoshop, but normally you would convert them to TIFF or FITS files and work on them in a program like ImagesPlus or similar to do your dark subtraction and flat divisions.

Once you have worked on them then you can save as jpegs and reduce from there.

[Shawn]

Sorry Paul , I should have been more specific, These are thumbs of raws befor processing, Im just alarmed at the increase of noise over an expose like this , Is this a function of accried heat in the sensor / camera, I It will dissapear with darks applied, but is this normal for a 350, or is mine crook,,?

Thanks for your reply
S

[Shawn]

I use Images plus too, BTW at this stage I have not applied flats to anything, Im still learning, the clear cold has just arrived...:>)

[[1ponders]]

I see what you mean now. If they are the same length of time then you by rights you shouldn't be getting that increase in glow. What earthly items/objects are in the direction your are shooting?

[Shawn]

Absolutely nothing Paul, pitch black out here aside from the stars, It looks as though the chip is not cooling down at all between exposures, am I taking the lights too quickly, Is there an optimum cool down time, ?.. I mean the last few in the sequence are pretty much useless. Iether there is something wrong with the 350, or gubbins here is overlooking a setting or something equally obvious to someone with clue...:shrug:...

:D

Shawn

[[1ponders]]

What is your normal process of image taking. It cerainly doesn't look normal and length of time between images shouldn't do that.

[Shawn]

Hi ya Paul..

The Camera is set at RAW, mirror lock on, noise reduction of off, I use Images plus for my sequences, but Maxim for guiding, CDC for pionting, thru the Ascom hub "POTH" all on Com 1, Ill set a typical run of say 10 @ 800 x 200 secs, 10 sec delay + 5 secs for mirror settle, total 15 secs between...
The Images I posted are the Raws, so are untouched, but if you look at the images it looks like 1 big 2000 second exposure with gaps,,, if you get my drift...

Thanks Paul

Am I missing something

[Kal]

Could it be the capture software that you are using that is progressively combining the images?

[Shawn]

Thanks Andrew I did think initially I had done something stupid with software, but I ser my camera to keep duplicates on the mem card as well as download to Images plus, these ones are straight off the mem card, and are identical to the downloaded ones, this is the first time my camera has behaved like this. Im really bloody confused at the moment...:(..

Ive been all over the net trying to find something that may help, to no avail...
Ill keep searching....

Cheers Shawn

...

[Geoff45]

Looks like a camera fault to me. Have you tried shooting raw on daytime (or late evening) subjects. If you do and get similar results, you can at least make the camera shop guy see that there is a problem.
Geoff

[Shawn]

Starting to look like a camera fault to me too Geoff.. Ill try what you suggest ...

Cheers Shawn

[JohnG]

Hi Shawn

Have you tried using a longer delay between shots. I use a 350D and normally shoot well over 200 seconds, but, I have a delay of between 30 - 60 seconds (depending on the outside temp) between shots. My camera dosen't display this behaviour at all.

May I also suggest turning off the LCD screen, you don't need it for astro shots and, placing the rubber viewfinder plug over the viewfinder.

Cheers

JohnG

[sheeny]

I've just had a look at this thread for the first time and I was going to suggest the same as John. Try increasing your time between shots to give the sensor time to cool. Worth a try...

Al.

[Shawn]

Thanks Al
Thanks John

I will try these, suggestions.

Cheers

S