Lemmon, guided on comet with PHD.

[tilbrook@rbe.ne]

Hi,

This is the most difficult image to process so far!!
I was amazed to guide on the comet with the orion mini guider. It was just showing up with 2 sec exposres, there was wind blowing straight into the dome buffeting the scope, so I'm surprised the images were ok.

I had a 6 goes at stacking in DSS, eventually had to set star registraion to 2% to get all the frames to register. I also did a stack in registax5, did'nt work as well as DSS. Still used both fianl images in PS.

8" astrograph - Heq Pro 5 mount - baader coma corractor - unmodded canon 1100D - cooler box.
8 x 8 minute subs - ISO 800.
Stacked in DSS median - stars and comets - processed in PS7.

Cheers,

Justin

[h0ughy]

Wow i appreciate the effort gone into getting this, the twisty tail is a treat

[alocky]

Nice effort - I've already spent a day trying to extract something useful from a similar guiding approach. I suspect part of the complexity you see in the tail in this particular image might be a registration problem between a few images.
If you play with the stacking parameters a bit you might be able to reject more of the stars.
cheers,
Andrew.

[tilbrook@rbe.ne]

Thanks David!

The tail is great and certainly the challenge on this comet.



Thanks Andrew!

Yep, complicated for sure!
Eventually I'll work out the best settings, thanks for the tip.

Cheers,

Justin.

[Matt Wastell]

The tail looks great! Congratulations.

[leon]

Certainly a fine effort, looks great.

Leon

[Larryp]

Nice, Justin!

[tilbrook@rbe.ne]

Thanks Matt!



Thanks Leon!



Thanks Laurie.

Cheers,

Justin.

[gregbradley]

That's a great shot You really brought out the tail well in that one.

Greg.

[Astroman]

Only just saw this, great shot Justin, tail looks terrific. can't wait to see what you get with the custom tracking feature of EQASCOM.

[astronobob]

A beaut capture Justin, are you stacking Raws, tiffs of Jpgs in DSS, I use Registax now as DSS isn't kind to me with some files :rolleyes:

[tilbrook@rbe.ne]

Thanks Greg!

The tail is the golden egg for sure.



Thanks Andrew!

Me too!



Thanks Bob,

I use tiffs, just my preference.
Registax is good for comets, easy to stack, just don't think it works quite as well on deep sky.

Cheers,

Justin.

[grantboxer]

Hi All,
I tried guiding with PHD on my HEQ5 mount but found the guider did not keep up with Comet Lemmon. I had the mount tracking siderial and the guider set on the comet. Any secrets here or settings that might need to be changed to follow comets?
Cheers Grant

[tilbrook@rbe.ne]

Hi Grant,

A couple of things to try.
Click on the brain funtion in PHD and set calibration step to between 1500 and 2500.

It may not aquire yet, move away from the comet to a star with a lower dec.
Make sure the star is on the same side of the meridian as the comet.
Go through the calibration steps and once guiding on the star stop the guiding. Move back to the comet and re-aquire.
This should work, it worked for me.


If it still won't work, you may need to take a dark frame.

Hope this helps.

Cheers,

Justin.

[RobF]

Great work Justin. What sort of Focal length and FOV would that image be?

[tilbrook@rbe.ne]

Thanks Rob!

F/L is 800mm and the field is 95 x 63 minutes.

Cheers,

Justin.

[Ross G]

Great capture Justin.

Ross.

[tilbrook@rbe.ne]

Thanks Ross!

Cheers,

Justin.

[ew]

Great shot and is that a satellite passing by, what are the odds

[tilbrook@rbe.ne]

Thanks Eric!

There's a lot of satellites out there, most of my Lemmon images have a satellite whizzing through them. I usually don't use those subs.

Cheers,

Justin.