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9. I suspect a DSLR is just not as “good” as a dedicated astrophotography CMOS camera.
James,
A DSLR can be used to get very good widefield images of comets, whole disc images of the Sun and Moon, and details of sunspots and lunar features. Your DSLR has a full-frame 14-bit sensor which can record a greater tonal range than a 10-bit sensor such as used in the Seestar S50, for example.
I have some dedicated planetary imaging cameras yet it’s still fun to attach a DSLR to a ‘scope and get some nice ‘large frame’ lunar vistas.
Alex.
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Hi James,
Not a detailed workflow, rather the key steps to enable DSS to stack comet images. See Nick Haigh’s advice here:
https://www.simplelists.com/baa-comet/msg/25949574/
Alex.
Hi James,
You’re welcome. On the baa-comet forum Nick Haigh outlined the workflow in DSS for comet stacking. This is also what I use.
To minimise saturating the coma yet bring out details in the tail you use the Luminance tab. Use your mouse to draw a box around its head and part of the tail, then gradually tweak the pairs of sliders for Darkness, Midtone and Highlight, each time clicking Apply to see the change – or Reset.
This is finicky work – it’s almost a Dark Art – subtle changes in the values can make a big difference to the image.
I’ve taken some screen shots of my steps in DSS, so I’ll retry comet stacking (stationary stars+comet option) and send you them (offline) in a PDF, either later today or tomorrow.
Cheers,
Alex.
Hi James,
I ran your darks, flats and lights through DSS, selected comet and stars tracking (star freeze effect) and got the attached image. It’s a pleasing view but it didn’t track the comet’s coma as well as I hoped. I’ll try it again.
You had 6 darks and 3 flats. As Nick advised, you need double figures of those to create good master darks and flats. DSS does a lot of the work for you but if you have only a few darks and flats, and if the masters are not good quality, they can produce a final image which can be worse than simply stacking all the lights.
Cheers,
Alex.
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Hi Paul,
I don’t have a Seestar but I found these presentations which might be of use, or at least of interest
https://www.youtube.com/watch?v=vMCf7nFMQmo
https://www.youtube.com/live/4BhlkOqo8cU?t=619s
Alex.
Hi Nick,
The STEVE phenomenon looks like that and it usually lasts for several minutes. Ask Sandra about your event.
I can’t confirm it on my meteor cameras but one of my north-facing ones recorded a very brief auroral ray brightening at 21:00:13 UT during lots of rapid changes (see attached). My full (mono) video from camera UK001H is here:
Cheers,
Alex.
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Hi Gordon,
Have a look at lockable garden storage boxes to see if one would be suitable.
Good luck,
Alex.
2024 PT5 was mag 17 when discovered in southern skies and is currently mag 22 at high northerly declination, but next January it will reach mag 18, within reach of more amateur imagers (if the MPC and NASA Horizons ephemerides fully include the perturbations from its flyby).
Alex.
I’ll pass on a piece of sage advice from my old supervisor – don’t use Dr. on a flight ticket!
In my case I used it on a hotel booking in Scotland and had a waiter (at dinner) asking my opinion of his back problems. I advised him to see his GP!
When on holiday a GP I know tells people they’re a vet.
Alex.
Many congratulations Doc. Wilson!
You can now expect to be asked by visiting tradespersons (as I once was) for assistance with treating assorted ailments!!
AlanAlan, Andy,
Our late friend Dr Dave Gavine – who was awarded Scotland’s first Open University PhD for his thesis ‘Astronomy in Scotland 1745–1900’ – related the story of a visit to the National Gallery of Scotland during which his mobile phone started ringing. As a member of staff walked over to reprimand him, Dave commented “Apologies, I’m a doctor…” 🙂
Have fun with your title.
Alex.
One team of researchers predicted ‘January 2024’, so that’s been and gone. Whenever T CrB erupts, I predict that I will be clouded out for ~20 days whilst it fades back to mag 10, but the weather will relent during the secondary eruption.
Alex.
I’ve attached the September Newsletter from ESA’s NEO Coordination Centre which gives a summary of the detection and impact of the asteroid.
Alex.
Hi Tim,
Thanks for correcting the e-mail address, I quoted the one in the 2024 Handbook. The shared link works fine.
Alex.
Hi Robin,
Nice sharp images with a good limiting mag. I had variable cloud cover last night, but during the clearer intervals my Leeds_N caught faint examples of your bright auroral rays through the Plough.
Cheers,
Alex.
