Albireo colour change ?

[Davey-T]

Just been to a dark site and was showing some one Albireo having told them about the colour contrast and thought at first the scope had GOTO'd the wrong thing as there appeared to be very little colour difference between the two stars, both looking yellow.

At home using the same equipment the blue component is obvious, so what was going on ? I thought a darker site would give better colours.

Dave 

[alan potts]

I don't doubt what you say Dave but it was OK for me last night. I do notice that some eyepieces do change the colours a little, e.g. in a Meade UWA they always look more rich for what of a better word.

Alan

[ronin]

What time was this?

[ely_ellis]

Could it be that because you were at a dark site, your eyes where more adjusted and so the pair were much brighter, washing the colour out.

Just a thought!

Martin

[Davey-T]

About 11.30 last night, using WO110FLT and 31mm Nagler T5, tried Meade 25mm plossl but still looked the same, usually use the Meade when star aligning the iEQ45 and as Albireo is one of iOptrons crack pot choices for an alignment star I get to see a lot of it

Took a few unguided shots of the Milky Way with DSLR and without my usual LP filter and star colours look great.

Dave 

[RikM]

Could it be that because you were at a dark site, your eyes where more adjusted and so the pair were much brighter, washing the colour out.

Just a thought!

Martin

This is probably the reason. Our eyes are only good at determining colour within a range of brightness. Too faint and objects just look grey, too bright and they appear whiter.

[Perseus_m45]

This is probably the reason. Our eyes are only good at determining colour within a range of brightness. Too faint and objects just look grey, too bright and they appear whiter.

Dave,  What Martin is saying here would imho be the correct thing. I will have a look see tonight myself.

                                                                                                                                        mike h

[cotterless45]

yep, i'll check it out. If you read any observation reports which include colour, you'll find considerable variation. It's a real wonder how we can even see colour at night,

Nick.

[ronin]

I asked about the time as I had an idea, then realised that when you said you looked later it was incorrect.

A WO110FLT and 31mm Nagler T5 should give correct colour.

Problem about eyes and brightness is that people have been observing Albireo for years and it is always gold/green or very similar and a WO 110mm scope is very nice but how many look at Alberio with 8" and 10" scopes, which will collect 4x the light quantity. Even a 6" Newtonian will have 2x the light gather.

So if that were the case surely many would comment about "What colour in Alberio?"

[Davey-T]

Could well be right as it's probably the first time I've looked at it from a really dark sight, Milky Way was clearly visible arching overhead and down to southern horizon, only get to see it from home dimly overhead a couple of times a year.

Bit knackered now after being up all night for three nights so will set up tomorrow (weather permitting) and see if it's turned blue again

Dave

[cotterless45]

I got orange red with green at x150 at 10.15. Then an hour later, yellow and yellow. LeeB had a look and saw yellow orange and blue !

Nick.

[Paul73]

22:30 classic gold and clear light blue here at 100x.

It wasn't properly dark. I think that this might cut down on the glare and let the colour shine through.

Paul

[RikM]

Yellow and blue for me in a 10" Dob at 23.30 last night. There was a light haze which made it fairly useless for DSO observing but star colours showed quite well.

[Davey-T]

I got orange red with green at x150 at 10.15. Then an hour later, yellow and yellow. LeeB had a look and saw yellow orange and blue !

Nick.

But did you have your observing head on ? 

Dave

[Perseus_m45]

I had a look see last night around 2300 est usa ..it looked the same as always..

                                                                                mike h

[Paul73]

I got orange red with green at x150 at 10.15. Then an hour later, yellow and yellow. LeeB had a look and saw yellow orange and blue !

Nick.

Nick

Are you sure that you I had the right star?

Judging by your description, you may well have accidentally strayed south a bit and got a traffic light by mistake

I guess that transient changes in atmosphic pressure / boundries would change the defraction characteristics and thus the colour??

Paul

[Davey-T]

Back home and pleased to say Albireo is back to normal, quick pic to prove it, three 60secs RGB unguided.

Certainly see a lot more stars around it from a dark site.

Dave

[Perseus_m45]

So many things can change coloration , this is just one example .

https://www.youtube.com/watch?v=wG6lxFW-pyQ

                                                                                    mike h