Wed 26th Beds Astro Meeting

[daz]

Had an enjoyable evening at the local astro club, looking at photo's taken of the Annular Eclipse in Madrid by one of the chaps.

He works a local public school and they have recently purchased a 40mm Colorado PST (handy eh??) so that went, along with a Celestron 80mm ED spotting scope and solar filter. He took a manual Olympus SLR and a Nikon Coolpix 4500 and had his wife use the SLR on the ED while he used the Nikon on the PST.

For a first-timer with the PST and Eclipse, they took some really good pictures, and I've already suggested he should make them available publicly. Will let you know when & where.

The images from the PST where very impressive, considering it's the bargain basement end of the range, and there is definite signs of (what appears to be) CA - experts in these things will no doubt correct me when you see what I'm on about! However, it picked up prominences on the limbs very well, and with the zoom on the camera, got in very close with some good details.

We then reviewed some of the latest images from Cassini, the moons of Saturn, the rings, and thr ripple effects caused by the shepherd moons. I'm trying to find the animation that showed this and will post it up as soon as I do.

Quite an enjoyable evening.....

EDIT: Here is an image showing Prometheus 'pulling' material out from the F-ring, the culprit behind the ripples!!

[Astroman]

CA=Chromatic Aberration? From a monowavelength telescope? I think not.

[OXO]

I Think the CA could be something from the cameras being used not the scope though..

Sounds like you had a great Night there Daz most interesting subjects too wish i could of been there..

JAMES

[FLO]

CA occurs when a lens acts as a prism and seperates light into seperate wavelengths.  What Astroman is saying - I think - is that the light viewed thru a PST is a single wavelength so cannot produce CA. 

If I had to guess, I would say that James is right and that what you are seeing is Bayer pattern artifacts (best not to ask) from the cameras imaging CCD. 

Steve

[AstroTiger]

Hi Daz

so ur a mamber of the bedford As are you?

I think i have your societies calender on my study wall. I am a member of the Northamptonshire Natural History society, i believe a number of our guys attend your doos. you certainly have a setup to be proud of.

martin taylor and bob marriott?

Would you happen to know them?

i am sure one day we will meet, as i intend to go to the next event if i can :-)

look forward to poss meeting you all sometime

Al

[daz]

Astroman / Steve - Badly worded original post. I realise that it is not CA, the guy demonstrating did go into a bit of detail on the construction of the filter and roughly how it works. What I meant to say was the effect on the image was similar to that of CA i.e. there was a 'fingernail' of a blue/purple colouring on the edge - bit difficult to see without the picture.....hopefully he will post it up somewhere soon

James / Steve - OK, can't remember if he mentioned that as a possibility

Al - Glad to see you have your ISP sorted!! Only been a member for 2 months and last night was my second meeting, so not had a chance to get many names. When I do, I'll mention your name!! And, looking forward to meeting you at some point too

[AstroTiger]

hi daz it would seem our (NNHS) guys are meeting ur guys next month,

I will likely but another calenda as i did last year :-)

Perhaps i might see you there?

Al