Observatory, telescope and equipment advice needed!

it is now a 14" scope!

BVRI filters (you can only use the U filter on very bright objects - like stars) are actually not too bad - about $1200 will get you a scientific grade set.

The demands of differential photometry in terms of procedure though would make you wilt instantly. Even taking unfiltered measurements you have to really nail the process - imaging standard stars (Landolt, Henden or similar), allowing for airmass and other quantifiable errors (first and second order extinction) and doing the basic calibration stuff (darks, flkats, biases). Mulitiply this process by x where x is the number of filters you are imaging through and photometry becomes scary.

I'd be surprised if unfiltered differential photometry would give meaningful results on asteroid rotation/shape. It may work for variable stars but in order to do asteroid light curve work, you really need to be producing results to an accuracy of no less than 0.03 magnitudes.

That said, you can still do basic photometry with a very meagre setup. And the upgrade path really only involves the filters. Photometry itself is more about hard graft and mathematics

Dave

It would probably be worth getting in touch with Michael Redfern in NUIG to get an idea on what is possible from Dublin Skies, and more importantly what is of scientific use. Their undergrad observatory has I think a 12" scope (it had a 12" LX200 but was upgraded); that is ran as a small professional observatory which is something like what you are aiming at. Though as you say you need to be careful not to forget the visual aspect.

Great idea Al. Actually Michael was the next person with whom I was going to get in touch. He's a friend of some family I have down there so he seems like the obvious cadidate to put forward ideas, especially when it comes to research.

Basic spectroscopy is certainly doable, I've got spectra with 4" scope and a $20 grating. Again Mike might be able to advise on what would be appropriate for research. Maurice Gavin[1] in the UK would also be worth getting in touch with for an opinion on spectoscopy equipment..

Yes, this seems an obvious choice. Something simple and practical for LC physics students. I haven't heard of Maurice but I'll get in touch anyway.

If this is where I think it is the trees should not be too much of a problem, they are blocking out a lot of direct light for you. Raising it a 'bit', a few feet, would probably be good, but I doubt that building it at 1st floor height will be worthwhile. Also check the plans for any new buildings nearby.

It's down by the cottage. I'll scout it out properly tomorrow and see what the view might be like from that sort of height.

I didnt see the option of remote control of the scope disccused to much yet. I assume that since the building will have power it will also have a network cable running back to the main building, though you might be in wireless range.

I'm quite sure that it would be within wireless reach of the main building but I can check that out with our computer expert.

Dave is probably right about the requirements for photometry being high. The BVRI filters alone would be expensive. However I think its worth keeping the options of basic photometry open; even if its with unfiltered light. You may not choose to get equipment capable of professional level observations, but reasonably accurate asteroid measurements would be within reach. Dan, you might want to ping Guy about this; he had mentioned that magnitude observations of asteroids was possible with amateur equipment and had a contribution to make in determining asteroid rotation and shape.

Another good idea! Guy might be the right person for asteroids. Still, I'd interested to see what the options on photometry are. There's obviously a lot for me to take on board but as I say, we've got one chance at this so we may as well try to kit it out for research for students and others.

Thanks for all the opinions!

I don't mean for this to sound negative at all. If someone gave me even 20 grand to spend on a setup, I'd really have to think very very hard about it. I'd have to think even harder if it was 100K...

Dave's advice is very sound. If there is serious money to be spent here then you'd do well to employ someone like Dave McDonald or Dave Lillis (for a modest fee of course) to ensure that it is spent wisely. More is often less in astronomy and to have the experience of people like the Daves to call on is what makes this site a boon to all astronomers.

I'd certainly like to play with the kit and would welcome the opportunity to assist in the construction (computers, networks and electronics are my profession) of such a project (FOC of course).

The demands of differential photometry in terms of procedure though would make you wilt instantly. Even taking unfiltered measurements you have to really nail the process - imaging standard stars (Landolt, Henden or similar), allowing for airmass and other quantifiable errors (first and second order extinction) and doing the basic calibration stuff (darks, flkats, biases). Mulitiply this process by x where x is the number of filters you are imaging through and photometry becomes scary.

Thats what the software is for

Airmass can be modelled in software. Extinction would be a problem in Dublin, but something that could be calibrated for; especially by say a young scientest project! Possibly an interesting project on local air pollution in itself.

Darks; flats etc. we'll you'll be doing that anyway for imaging.

I guess Dave has tried photometry so knows how hard it is to do in practice. I've only done the theory and done the measurements and calculations from observatory images.

I'd be surprised if unfiltered differential photometry would give meaningful results on asteroid rotation/shape. ... in order to do asteroid light curve work, you really need to be producing results to an accuracy of no less than 0.03 magnitudes.

Perhaps we're disareeing on whats 'meaningful' For detailed sumbissions to relavent bodies that sort of accuracy may well be needed. However the amplitude of the curves for some asteroids at least can be up to 1 magnitude. So although you will have large errorbars, you will be able to detect the rotation. I'd imagine that that might be meaningful for a school project with careful selection of targets though perhaps of limited value for formal research observations.

That said, you can still do basic photometry with a very meagre setup. And the upgrade path really only involves the filters. Photometry itself is more about hard graft and mathematics

I think thats the important bit. Variable Star stuff should be no problem. But accurate photometry could be an open ended project. For the sake of spending $1200 you might get some good young scientist or 4th year projects out of seeing just how accurate you can get.

Cheers,
~Al

Dan,

I would just like to second everything that has been said before. Especially Dave McD's advice about getting the goals straight. I would go even further than that and decide what the criteria for success of each goal should be.

Let me elaborate. Take the astro-photography goal, do you want to take pretty pictures or do you want to take research grade images? Do you want to image deep sky objects or planets or both. Do you want to image brighter objects or do you want want to do supernova surveys of 18th magnitude galaxies? All of these decisions impact critically on your choice of equipment. Also some of the goals you might have in mind may not be possible from light polluted Dublin.

I dont know how to put what I'm about to say other than bluntly. If you wish to spend 100K on this project you need to employ the services of a team who will analyse your requirements and build the facility around it. You cannot do this yourself with the well meaning (and excellent) advice of people on a bulletin board. This is the blunt bit (forgive me) It does not appear to me that you are in the position (experience, knowledge) to make the critical choices needed to make this a success. You need a project management team around you for a project of this scale. However the good news is I think you are aware of that.

I often dreamt of what I would do with 100K to spend on astronomy. I came to the conclusion that I would not spend that kind of money on equipment sited in Dublin or even Ireland for that matter. I know location is fixed for you but I can assure you that that class of equipment cannot be used to near its maximum potential at a site in urban Dublin.

However you decide to procedd, I wish you well with the project and hope it meets all your expectaions and much more.