Gamma Cygni Nebula

[mike1485]

Hi All

I am very new to this hobby and feeling my way and learning loads. I took delivery of my EQ6R-Pro on Thursday evening (I have been struggling with a Nexstar 8SE mount to date!). As Thursday was the last forecast night of clear skies for some time to come I quickly unpacked and set up the mount and attached my rig (Canon 300mm f2.8 lens, ASI533MC, ASI120MM, ZWO Mini Guidescope, ASIAIR Pro).  After fumbling my way through working out the ins and outs of the new mount I managed to grab a couple of hours of 300s subs on the Gamma Cygni Nebula using an Optolong L-eNhance filter.  I was completely blown away by the tracking performance of the EQ6R-Pro (particularly after having been using the Nexstar).  This is the resulting image that I have processed in Pixinsight.  I would really welcome any constructive criticism to help me learn for the future.  I am aware that Sadr has a very significant halo.  I actually quite like this as it adds some drama to one of the key focal points of the image but would welcome views.  I am not sure how I would reduce it if I wanted to - my Pixinsight skills are not there yet!  I am also aware that I have sharpened the image a little more than some might.  Again, I like the effect but would welcome comments.

Thank you for looking and reading.

[wxsatuser]

Very good image with the new kit.

The halo seems odd, strange diffraction pattern across it, surprised that the Canon lens produced this.
Strange things can happen with bright stars but may be the halo is from the rest of the image train, filter may be?

[mike1485]

Thanks Mike - I appreciate your comments.

Yes, I had noticed that diffraction pattern and I don't know where it has come from.  I had stopped the lens down from f2.8 to f4, I wonder if that might have contributed?  I guess it could be the filter as you suggest - do you know if the Optolong L-eNhance has been known to cause this before?  I think I will need to do some experimenting when I can next see a bright star in the sky!  

[wxsatuser]

Cannot help with the filter but it may cause a reflection, may be some one else will comment on that.

Re diffraction spikes.
As you stop down they become more noticeable.
An even number of of blades gives the same amount of spikes, 4 blades 4 spikes.
An odd number of blades produces double the amount , 9 blades 18 spikes.

You either love or hate spikes, me I don't care, it's something we have to expect if we use camera lenses.

[mike1485]

Thanks Mike

I have just checked the specs for the canon 300mm f2.8 and it has 9 blades.  It's a bit difficult to count them but it looks plausible that there are 18 spikes there.  Thanks for that information.

I just checked out your website link - some great Ha work there!

 

[tooth_dr]

1 hour ago, mike1485 said:

Thanks Mike

I have just checked the specs for the canon 300mm f2.8 and it has 9 blades.  It's a bit difficult to count them but it looks plausible that there are 18 spikes there.  Thanks for that information.

I just checked out your website link - some great Ha work there!

 

Nice start with the mount    That's a great region packed with nebulosity.  I'm also in the camp that doesnt mind spikes (I image with a reflector so no choice here!), but sometimes camera lens spikes can be a bit overpowering.  It is possible to stop down the lens using a step down ring/rings, so you leave the iris blades physically fully open, and close the aperture with an alternative method.  The rings are cheap too.

[Sunshine]

Not being an imager I cannot offer any constructive criticism but I do know a beautiful image when I see one, wonderful work!.

[mike1485]

25 minutes ago, tooth_dr said:

Nice start with the mount    That's a great region packed with nebulosity.  I'm also in the camp that doesnt mind spikes (I image with a reflector so no choice here!), but sometimes camera lens spikes can be a bit overpowering.  It is possible to stop down the lens using a step down ring/rings, so you leave the iris blades physically fully open, and close the aperture with an alternative method.  The rings are cheap too.

Thanks for this tip.  I will look into that option.

[mike1485]

18 minutes ago, Sunshine said:

Not being an imager I cannot offer any constructive criticism but I do know a beautiful image when I see one, wonderful work!.

You are very kind - I am pleased you have enjoyed it.