How 'automatic' are filter wheels?

[Vega]

Strictly hypothetical (I am resisting the final step to the 'TRUE' dark side...ie LRGB CCD imaging)

At the moment I have been used to using Images Plus to set up my imaging session via computer and send all the instructions to my DSLR (So I can just set it up and go in to have a cuppa). With this in mind I have a couple questions with regard to CCD imaging...

1. Is this automatic imaging also possible with CCD camera's?

2. Is there such a thing as an automatic filter wheel which can be given instructions to change the filters during an imaging session via computer (which has all been preset by the user requiring no actual visits to the computer or kit) ?

Now im showing how lazy I am

Matt

[Ben Ritchie]

2. Is there such a thing as an automatic filter wheel which can be given instructions to change the filters during an imaging session via computer (which has all been preset by the user requiring no actual visits to the computer or kit) ?

Yes, my robofocus + TrueTek motorized filter wheel + CCD + CCDSoft would happily do automatic LRGB imaging with refocus between filter changes. Maxim and AstroArt can also do the same thing.

Takes a bit of tweaking to get everything to work properly, but then it all works very well.

[Aza]

I have an Atik Electric Wheel.

With that I can set it all up for automatic use. It will change filters and take exposures in any order and length that I have preset

[Vega]

Sounds good. Whats the benefit of 2" filter wheels over 1.25" ? At the moment I cant see the point of spending out on 2" filters over 1.25" ones.

Also I like the look of the QHY8 Pro but alot on here use the Atiks. I guess the QHY cameras can have compatible automatic filter wheels too or are Atiks more suited to automated setups?

Sorry for all the Q's

[brianb]

im showing how lazy I am

Why bother getting out of bed? Just have the robobutler bring food & clear away the excreta....

[Ben Ritchie]

Sounds good. Whats the benefit of 2" filter wheels over 1.25" ? At the moment I cant see the point of spending out on 2" filters over 1.25" ones.

Larger CCDs need 2" filters to fully illuminate the chip (the largest even need square 50mm-ish filters rather than the usual 2"). If you're not using a large CCD then 2" filters aren't needed ... 1.25" filters are much cheaper.

Must admit that fully-automated imaging reached a point where I wondered 'why'. I don't like processing that much, and there didn't seem much point in staying in bed while some kit worked away in the garden.

[Aza]

Also I like the look of the QHY8 Pro but alot on here use the Atiks. I guess the QHY cameras can have compatible automatic filter wheels

QHY8 Pro is a OSC camera so a filterwheel is not needed.

If you want to shoot Ha then it would be simpler to screw the filter onto the nosepiece.

[daz]

Vega

MaximDL can be set up to take a number of exposure on one filter, change filter, take the next set and so on - no problem.

You can then use something like CCD Commander which can do other things: Auto pier flip, plate solve and reaqauire target; automatic dusk/dawn/dome flats; auto park when complete; change target based on time/declination; auto focus; rotate the camera (if using such a device); rotate dome (if connected); find a suitable guide star; etc, etc.

It will do as much or as little as you want.

I am aiming down this route, except the focusing bit. I like to think that this is the only interaction with an otherwise mechanical process, so I'd at least like to say "I focussed it!!". The skill comes in the processing, I think.

CCD Commander has a 45 day trial on it as well.

[Whippy]

Must admit that fully-automated imaging reached a point where I wondered 'why'. I don't like processing that much, and there didn't seem much point in staying in bed while some kit worked away in the garden.

I know what you're saying Ben, I was chatting to Daz about this and whilst I fully understand and appreciate people wanting to have everything or near as fully automated especially if they've got an obs/permanent setup, I like the mechanical process of setting up (bar polar alignment) and being there whilst the setup gathers data, plus I normally observe at the time time anyway. Perhaps I'll rethink this if I ever get the chance to have an obs but even then I don't think I'll be able to sleep while the kit does it's thing anyway!

Tony..

[roundycat]

For what it's worth my kit is capable of being fully auto except for focusing. Depending on the scope and assuming the filters are parfocal I often focus in green and then let the RGB sequence run. I will check every so often that focus is still good plus I have to occasionally check that the roof is still out of the way as I only open it as much as is needed for an hour or so. I also like to check the twelve or so wires that come from the cameras etc to make sure they are not getting tied in knots. Plenty to do during a session including doing a bit of observing on the side with the bins.

Dennis

[daz]

Thats a good point Dennis - checking things are not in the way!

My plan is to have the dobbo on the patio while the imaging ring does its thing!

[Vega]

MaximDL can be set up to take a number of exposure on one filter, change filter, take the next set and so on - no problem.

Thanks Daz. I presume MaximDL is compatible wth most auto filter wheels and my choice of filter wheel shouldnt be affected by choice of CCD camera. (Was eyeing up an Atik filter wheel and QHY camera... bit of a conflict of manufacturers lol but I guess it shouldn't matter?)

I dont plan on automating the framing, focusing polar alignemnt or guiding! :-D

Matt

[Ben Ritchie]

I dont plan on automating the framing, focusing polar alignemnt or guiding! :-D

I found automating the framing (by slewing, plate-solving and recentering) one of the most useful bits, as it makes multi-night runs much easier.

[daz]

Yes Matt, Maxim is compatable with most things - if not, there are ASCOM drivers available for most things!!

[Aza]

I found automating the framing (by slewing, plate-solving and recentering) one of the most useful bits, as it makes multi-night runs much easier.

This is something I would like to do!

Do you need EQMOD for this? And is it simple to do?

Cheers

[Ben Ritchie]

Do you need EQMOD for this? And is it simple to do?

I used CCDSoft and TheSky, I think Maxim can do it too - maybe other stuff, all it really needs is some cooperation between the CCD software and planetarium software.

Basically I take an image with CCDSoft, use TheSky to figure out exactly where the telescope is pointing (it has an automated 'image link' function to compare the image against its star charts to work out the coordinates), resync the telescope to those coordinates and then do a final short slew to the target ... which is now exactly where you want it. Do the same the next night and the two datasets overlap near-perfectly, to within a few pixels in my case.

Once you're setup it's extremely easy, just a few mouse clicks. Obviously rotation's still an issue though if you move the CCD between runs, so best for an observatory setup.

[Psychobilly]

You got to be out there with it ... if your going "robo" you might as well just buy time on a decent scope somewhere where there are decent clear dark skies.... and ideally more southerly as well...

[Aza]

Cheers Ben, I shall have a look into that

[Dangerous-Dave]

Just to add my two pennorth, I used to think USB filter wheels were an unnecessary luxury, but having lost my customary "two hours kip on the sofa" (with the 20D) to jump up and change filters I'd give my right arm for one now (not that I can afford it like).

D