Weather cleared tonight, so managed a shot of Boattini. So much brighter than a month ago.
This shot is a stack of 3 x 180 sec subs taken with piggybacked Canon 400D at 55mm, ISO 1600, F/4. Hand-guided using slow-motion controls on EQ1 mount, and NexImage through Tasco 4.5" f8 reflector. Stacked in Registax.
Weather cleared tonight, so managed a shot of Boattini. So much brighter than a month ago.
This shot is a stack of 3 x 180 sec subs taken with piggybacked Canon 400D at 55mm, ISO 1600, F/4. Hand-guided using slow-motion controls on EQ1 mount, and NexImage through Tasco 4.5" f8 reflector. Stacked in Registax.
Note the carbon star (HIP 53085) above the comet.
Cheers -
Nice shot Rob! I got tripod trail images tonight, and i took a pic through my 8" SCT last night, which i havent posted. Looks really nice!! Good stuff! I estimated visually a mag of 7.8, and Dia of 11.5', through my 10" f/5 dob @ x31. I did notice that red star in my trail image but i thought it must have been a hot pixel, but then again...pixels dont trail do they!! Interesting!!!
Thanks for pointing that out! Cheers!
Hi guys, heres a 60 sec exp, Canon 400D, ISO 1600, 168mm @ f/5.
Just lightened midtones and adjusted contrast a little, the comet and carbon star are quite noticeable hey!
It's not just a "rapid" brightness increase. The comet is now becoming visible in smaller apertures.
As the comet gets brighter, observations through telescopes (and ultimately binoculars) of smaller aperture tend to rate the comet as much brighter, compared to observations from weeks earlier through larger telescopes - and even brightness estimates the same night in a larger telescope.
It's fairly well documented - on a given night, binoculars and small telescopes will appear to show a comet brighter than through a larger telescope.
Of course, when the comet is at its brightest, we'll tend to observe it through the smallest aperture available (unaided eye -> binoculars -> small telescope). So, we're more interested in what the brightness estimates are from those small apertures.
What will be interesting in the next few weeks is to follow the comet's brightness as measured by observers using binoculars and small telescopes. That will provide a better indication of what to expect in June and July.
...fortunately I have 4 more weeks before the July/August issue of Australian Sky & Telescope magazine goes to print - so we might be able to better forecast the comet's peak brightness by then.
Regards,
Greg
ahh could be a bit of that, ive read outlandish predictions on BAA site before tho,
I see some are sayin 3.5 - 4 max that I could believe easy, mag 2 is a LOT brighter than 3.5, as everybody knows i dont think i am splitting hairs saying that either
cheers!
As the comet gets brighter, observations through telescopes (and ultimately binoculars) of smaller aperture tend to rate the comet as much brighter, compared to observations from weeks earlier through larger telescopes - and even brightness estimates the same night in a larger telescope.
It's fairly well documented - on a given night, binoculars and small telescopes will appear to show a comet brighter than through a larger telescope.
Of course, when the comet is at its brightest, we'll tend to observe it through the smallest aperture available (unaided eye -> binoculars -> small telescope). So, we're more interested in what the brightness estimates are from those small apertures.
Regards,
Greg
I would also like to point out that if the comet does get brighter it will be harder to make brightness estimates using binoculars that do not have sufficient back-focus to use the VSS method of making brightness estimates if the coma grows sufficiently larger.
In the case of 17P / Holmes brightening i noticed that experienced observers resorted to using opera glasses to make VSS methods possible due to large coma size.
I might have to get to know my binoculars a bit better over the next few weeks to get used to making brightness and coma dia. estimates.
Last edited by Outbackmanyep; 29-04-2008 at 04:20 PM.
I observed Comet Boattini last night and it looked a lot better than my last observationI must make a confession, Most of my observations have been using a 13 mm Nagler in the 16",at 140x mag spreads out the light so making the Comet seem dullerlast night I used a 30mm Plossl and it was a much brighter looking object
Ron
Finally sat down and worked out how to upload data into the Argo Navis so I could hunt down this comet.
After a couple of looks in my light polluted backyard using my new TV 13mm Nagler, I was surprised how dim this object is. It seemed to be barely a smudge really. No wonder I couldn't find it before!
After reading this thread, perhaps I may be better served using the 24mm Panoptic or even the GSO 32mm Superview?
Wider fields always make a dim object brighter, a lot of comet observers do their mag estimates by binoculars, but of course this is not always the way to observe them. With my 10" dob i use a 40mm plossl with homemade reticle built in to help me make coma diameter estimates and this works fine, a larger aperture always helps but using the lowest power practicable!
I hope that you Deeno, and Astroron, that you have a fun time observing this over the next few months! Cheers!
Just come in after looking at Comet Boattini through the 30X100 binos. Easily found using Starry Night and a hand drawn finder chart. Appears as a large fairly bright smuge. No sign of a nucleus.
Had to hand hold the binos as it is so close to the zenith, interesting excercise.
I made the comet out at mag 6.9 last night, tried to get an unaided sighting but was not successful, i did however manage to work out my Limiting Magnitude to mag 6.9 using averted vision, the comet is large and fuzzy, im guessing it wont be naked eye in dark skies until it reaches 6.5 or less.....
Observed the comet several times last week in very dark skies, using 12x50 binoculars. Was amazed at how large it looked, a big, bright dusty ball. No sign of nucleus. Looking forward to next month...
Found comet easily last night in my new 11x70 binoculars. Surprised at how large it was, diffuse and fainter than I though it would be, though sky not yet totally dark after Moonset. Couldnt find it with scope, then ran outa patience. A beautiful binocular sight though.
Keep viewng it under moonlight too! The moonlight will drown out the outer coma regions but the central regions should still be quite visible in binoculars and telescopes.
I managed to glimpse it naked eye using averted vision on the 8th May, but it was rather close to mag 6 stars in the field and i didnt want to make it public until other reports came in.
Hey guys, i made W1 out at mag 5.5 last night with my 7x50 bins, DC= 3 and dia of about 15'. The coma size is actually quite large but moonlight washed out the fainter outer coma region. No tail still.
Should be a nice sight when the moon buggers off!
What a difference darkness makes - when I estimated its size last night here in the suburbs with my 8" newt I got to 16', and that was being generous... This comet does respond well to UHC-E filtering though - that's the good news....
i dont think i am splitting hairs saying that either 
last night I used a 30mm Plossl and it was a much brighter looking object
