Log in

View Full Version here: : Sweet Lemmon


orestis
07-02-2013, 10:16 PM
Hi everyone:hi:,

This comet is a splendid sight, to capture it on the sensor was also quite a joy. Not the best quality image , very noisy but for the equipment I think it turned out alright.Particularly as I can just see a hint of the tail to the left of the coma.

Any tips on processing will be greatly appreciated as I just can't get rid of the noise but it is expected for the high iso.

Equipment used was a Canon 550D with Ef 15-85mm lens on a eq mount, manually guided by hand estimating rotation of the slow motion control.

Image details- 30 seconds , f/5.6 at 3200 iso.

Thanks for viewing
Orestis

PS- Is there anybody that knows the exact rotation rate I should turn the shaft ?

Johno
07-02-2013, 10:30 PM
Orestis, that's great work tracking by hand.
Best way to reduce the noise is take several shots like that and several 'dark' frames as well and stack them all using Deep Sky Stacker. It will make a huge difference to the contrast of the final image.

orestis
08-02-2013, 06:17 AM
Thanks Johno,

Yeh I realised that I should have taken some darks to reduce noise, but over a period of time wouldn't the comet become trailed as DSS stacks the images.

Is there any settings where it can stack on a selected object in each frame?

Cheers
Orestis:thumbsup:

Johno
08-02-2013, 10:59 AM
Yes, with DSS you can choose to register on the comet, the stars or even both. In the 'both' mode I think it basically registers on the stars then adds the comet back in from one particular frame. There are a few tutorials around which I found helpful and the manual is quite good. You'll need to spend a bit of time experimenting with it though. I find the interface a bit confusing. I also find however the most difficult part of all is the post processing.

You should definitely try using some dark frames. It's very easy to do and is quite effective in reducing the noise.

orestis
08-02-2013, 07:50 PM
Thanks for the info Johno,

I too find the post processing difficult.I guess I just got to keep practising.

Cheers
Orestis:thumbsup:

Ross G
08-02-2013, 10:51 PM
Great capture Orestis.

Ross.

orestis
09-02-2013, 08:29 AM
Thanks Ross,

Comet Lemmon is putting up quite a show.

Orestis:thumbsup: