First Light 50D and Hutech IDAS P2 LPS Filter

[DJ N]

Hi all,

The other night, managed to get a first light with my new 50D. I am a bit concerned, as there is some horizontal banding on the images, but I am not sure if this may have been caused by the "entanglement" of all the cables (USB, power etc...) due to my rush to beat the clouds. I will need to do a more formal 2nd light next time I have some more favourable conditions.

Anyhow, my first test image was of M20.

6x 8min lights, 9x 8min darks @ ISO800 with the 50D and Hutech IDAS P2 LPS filter on the ED120. Stacked in DSS and a quick process in PS3.

The second image is one of the subs indicating the banding.

Thanks for looking and would appreciate any comments.

Cheers

Daniel

[dugnsuz (Doug)]

Nice work Daniel.
The processed image looks a litle washed out colour wise, but holds a wealth of detail - even evident from the compressed 200kb jpeg.
Looks very promising.

Re banding - I haven't had this problem myself, but anecdotaly it would seem that this problem is closely associated with data/power cable entanglement - you're obviously on top of this problem so I hope you sort it out.

Doug

[gregbradley]

Very nice. What are the stats on the 50D is it 14mp or so?

Not sure what the banding is. Whenever I have seen something like
that it was a short underexposed shot. I take it this was an 8 minute sub?

I have never had a problem with my CCDs with cables a bit tangled.
Did it happen sometimes but not other times for the same long 8 minute exposure?

Perhaps post a question on the digital astro camera Yahoo group where lots would be using 50Ds.

There was an issue with some 20Ds but as I recall that was more of a large dark band in the middle of the image and different to that look.

Greg.

[RB (Andrew)]

Originally Posted by DJ N

Hi all,

The other night, managed to get a first light with my new 50D. I am a bit concerned, as there is some horizontal banding on the images, but I am not sure if this may have been caused by the "entanglement" of all the cables (USB, power etc...) due to my rush to beat the clouds. I will need to do a more formal 2nd light next time I have some more favourable conditions.
..
Thanks for looking and would appreciate any comments.

Cheers

Daniel

Daniel to me it looks like regular noise due to the long exposure.
The 50D is said to have more noise at higher ISO's than previous models due to it's pixel density.
My guess is that it is inherent in the camera.

I do hope it's simply the cables but the only way to verify this is to try again with the cables restrained.

Hope you get it sorted, let us know how you go.

[multiweb (Marc)]

Nice pic. Very sharp. I got this banding occasionally too. From what I gather it is caused by USB cables nearing power cables as Doug mentioned. It can also be linked to how busy your laptop or USB pipe is when you read/download the picture into your HD.

[DJ N]

Will definitely let you guys know how I go. Was hoping for a quick set-up tonight, but the cloud has rolled in.

Thanks for the feedback.

Cheers.