NGC7822 - Part of Question Mark Nebula - Ha 3nm 268M

[tooth_dr]

Another mono image, due to the moon being around when the sky was clear!

APM LZOS 105/650 with 0.75x RIR

QHY268M camera

Chroma 3nm Ha filter

31 x 300s subs (approx 2.5 hours)

 

Any comments welcome!

Adam.

[Rodd]

Very nice.  More signal than mine. Very nice

[geeklee]

16 hours ago, tooth_dr said:

Another mono image, due to the moon being around when the sky was clear!

Looks great again Adam.  As well as the detail in the centre, those "waves" alongside the subtle transition of faint nebulosity on the far right centre looks fantastic too.  

I shot this recently with the Samyang 135 so it's been good to see better close up versions ( from @Rodd and now yourself most recently).

[tooth_dr]

7 hours ago, Rodd said:

Very nice.  More signal than mine. Very nice

I was looking at yours too Rodd. Very comparable I think.  Interesting comparison as we have the same aperture, just a difference in focal ratio and you have a bit over 2x exposure time 

[tooth_dr]

3 minutes ago, geeklee said:

Looks great again Adam.  As well as the detail in the centre, those "waves" alongside the subtle transition of faint nebulosity on the far right centre looks fantastic too.  

I shot this recently with the Samyang 135 so it's been good to see better close up versions ( from @Rodd and now yourself most recently).

Thanks Lee.  Ha really shows up the fine detail and structure. 

[Rodd]

1 hour ago, tooth_dr said:

I was looking at yours too Rodd. Very comparable I think.  Interesting comparison as we have the same aperture, just a difference in focal ratio and you have a bit over 2x exposure time 

I think the big difference is the camera. 16 bit back illuminated compared to 12 bit front illuminated.  But that should have been accounted for by the difference in exposure time- unless 3x is the differential

[tooth_dr]

8 minutes ago, Rodd said:

I think the big difference is the camera. 16 bit back illuminated compared to 12 bit front illuminated.  But that should have been accounted for by the difference in exposure time- unless 3x is the differential

I think the new generation of cameras are excellent, but dont know enough about the electronics/science to comment.  Is F3 versus F4.65 going to make much of a difference?

[Rodd]

50 minutes ago, tooth_dr said:

I think the new generation of cameras are excellent, but dont know enough about the electronics/science to comment.  Is F3 versus F4.65 going to make much of a difference?

Our apertures are the same, so same number of photons.  They are distributed differently, but not that differently.  Your sensor is 63% larger so the FOVs are pretty close.  You are shooting at 487 mm with reducer and I am shooting at 318 mm with reducer--the larger sensor just about equalizes the FOV, but not quite.  Your resolution is higher.  I am shooting at 2.46 arcsec/pix.  You are shooting at 1.59 arcsec/pix.  If you had good seeing, your image would contain more details as long as focus and guiding were good.  Both scopes are high end- I think yours is a triplet and mine a Petzval--but I don't know enough about optics to compare.  I think the biggest difference is the camera.  The 2600 (I think the QHY 268 uses same sensor as ZWO 2600) is considered a major upgrade from the ASI 1600.  I can't wait to get one.  I'd love a 6200, which is the same just bigger (full frame).  But I would need 2" filters and they costs as much as the camera--so it turns into a major expense.  Maybe if I sell my FSQ (haven't been happy with it.  TAK tells me now that the optical design was not intended to work with small pixels.  I see yours doesn't have a problem with it, so seems like bunk to me).

[Sunshine]

A beautiful image! an APM LZOS 105, what a wonderful instrument!

[tooth_dr]

4 hours ago, Sunshine said:

A beautiful image! an APM LZOS 105, what a wonderful instrument!

Thanks, and I agree the 105 is just great, and the only way to make it better was to get a second one 😇

[Sunshine]

11 minutes ago, tooth_dr said:

Thanks, and I agree the 105 is just great, and the only way to make it better was to get a second one 😇

Why have one when you can have two at twice the price! 🤣