[RCC] Lunar image of Montes Apenninus et al Requests for constructive critique · Leela.Astro.Imaging · ... · 5 · 186 · 0

Leela.Astro.Imaging 1.51
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Hello,

I would appreciate constructive feedback of my image of Montes Appeninus and the surrounding region pls - https://app.astrobin.com/i/1pu0g4

It's prompted by seeing an IOTD of the same region (https://app.astrobin.com/i/7udnjf).  If you have the time for comparative feedback that would be even more appreciated - this is not to throw shade at the IOTD image, more that as both images are of the same lunar region (albeit at slightly different days in the lunar cycle), it will be a good comparative learning for me.  (Obviously there is nothing I can do about the aperture difference in the scopes!)

Thanks in advance.
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andreatax 9.89
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Theirs: Quite good but wouldn't be worth mention never mind IOTD (how the mighty have fallen!) except it was done with a 10" which is remarkable on its own. Sorry if I hurt feelings here. As per the below comment about the absence of colours, that alone would on its own  bar the grade if it were for me. Lucky them.

Yours: can't really be compared and the difference in diameter is telling. It's OK, but you would need to improve on several areas, one of which is to shoot colour instead of IR (you are basically given up on resolution here), at least you get to play with mineral colours and make more impression rather than a vastitude of grays.
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afd33 9.38
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Lunar/solar/and planetary aren’t my strong suit, but I can give you my opinions about the non technical parts of it. 

I prefer the framing of the IOTD.

I also prefer the overall brightness of that one more. My original edit said moon phase but I don’t think that’s it. I think it’s that theirs fills more of the frame. 

Then I’m on my phone so this may or may not be true, but theirs looks a decent bit sharper than yours. Could be better seeing, bigger scope, whatever, but is what it is.
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Gondola 8.11
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I think the normal sized presentation has good tonality but if you enlarge the image it starts to break down. I'm afraid that no matter what you do, when it comes to lunar imaging aperture is always going to win. Look at the Hadley Rill area in the winner and compare that to yours and you can see, it's no contest. Shooting IR can be effective especially for large apertures but at 145mm it might be questionable. You haven't over sharpened and that's good. You haven't posted your session information but I can give you some basic lunar imaging advice.

Don't shoot unless the seeing is good.

If the seeing is good, a green filter will probably give you the best resolution.

Shoot a ton of frames, 4000 at least and more never hurts.

Cull the frames down to the smallest number of frames you can get away with. This will depend on noise so you'll have to experiment, 100 to 200 would be typical.


I think you can improve on what you have but at the end of the day, aperture is the real limiting factor. What you need to do is shoot for the best that your aperture can do.
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Leela.Astro.Imaging 1.51
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Thanks all, that's really useful feedback.  Yes the difference in aperture is stark - that extra resolution makes such a big difference.  I'm not going to chase aperture though as mundane storage and mounting logistics make a strong argument against that for the foreseeable future.  I'd much rather have a scope I'm more likely to use than a big beast which feels like a burden to set up, and a burden sitting guiltily in the corner when you're not using it!  Plus, sadly, the seeing here supports 7" at most on just a handful of nights a year so I'm not sure it would ever get to 10".

The colour/green point is interesting - I will try that.  Luckily the camera I use is a colour one, but in IR becomes mono so I often use it in that mode (both to cut through inner city seeing conditions, as well as the better resolution that a mono sensor would give(?)).  But I have tried it with a contrast booster filter in OSC mode, so I'll do that a bit more to see how it comes out.

Yes the difference in brightness is also very palpable.  I don't like to boost brightness too much in processing - preferring to let the natural lunar shades come out as they are, but I can push it a bit more without clipping the histogram.  The brightness slider on astrobin is actually quite handy b/c playing with that shows the benefit that would bring too smile

On the capture side, I normally take 2000-5000 frames, and usually keep just the top 1% (unless the AS4 quality curve shows that conditions were good enough to take it to 3% - usually not the case).

Thanks again all - v helpful, and exactly what RCC is for.  Much appreciated!
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Gondola 8.11
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Thanks all, that's really useful feedback.  Yes the difference in aperture is stark - that extra resolution makes such a big difference.  I'm not going to chase aperture though as mundane storage and mounting logistics make a strong argument against that for the foreseeable future.  I'd much rather have a scope I'm more likely to use than a big beast which feels like a burden to set up, and a burden sitting guiltily in the corner when you're not using it!  Plus, sadly, the seeing here supports 7" at most on just a handful of nights a year so I'm not sure it would ever get to 10".

The colour/green point is interesting - I will try that.  Luckily the camera I use is a colour one, but in IR becomes mono so I often use it in that mode (both to cut through inner city seeing conditions, as well as the better resolution that a mono sensor would give(?)).  But I have tried it with a contrast booster filter in OSC mode, so I'll do that a bit more to see how it comes out.

Yes the difference in brightness is also very palpable.  I don't like to boost brightness too much in processing - preferring to let the natural lunar shades come out as they are, but I can push it a bit more without clipping the histogram.  The brightness slider on astrobin is actually quite handy b/c playing with that shows the benefit that would bring too

On the capture side, I normally take 2000-5000 frames, and usually keep just the top 1% (unless the AS4 quality curve shows that conditions were good enough to take it to 3% - usually not the case).

Thanks again all - v helpful, and exactly what RCC is for.  Much appreciated!

The other point I would make is, don't worry too much about what your average seeing is. You still want to avoid the really rough nights but the whole point of lucky imaging is to beat the seeing.  If you had a true mono camera with the same pixel size, resolution wouldn't increase to a perceptible degree so I wouldn't worry about that. 

One last thing, make sure you are oversampling enough. The ideal shooting focal length is 5 x your pixel size in microns. in your case, 5 x 2.9 = F/14.5 

Have fun!
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