460ex purchase imminent - final questions

[peroni]

Hey all,

So, I have approval and budget to get the Atik 460ex. Now I need a sanity check before hitting the buy button.

I have a Skywatcher Evostar ED80 scope and the FF/FR. My interest is in giving narrowband imaging a go to maximise my chances of a clear evening. 

I'm at the limit of my budget (£2200) and my purchase list consists of ...

Narrowband filters here

Atik 460ex mono here

Manual filter wheel here

1)  I don't have room in my budget for RGB filters yet. Is that a showstopper?

2)  I have power in the obsy so would I be better getting the Atik 12v power supply here?

Or should I connect the camera to my 12v bench supply here? Using one of these (I don't have a soldering gun)

3)  I have a collection of adapter rings but probably not the correct ones. What do I need to connect the 460ex up to my scope?

I see the Atik 414ex is available soon but I think I'll prefer the FOV provided by the 460ex, I'm coming from a DSLR (Canon 1000D). I've seen people refering to Nyquist, sampling and resolution; most of it goes over my head...

Blackwaterskies gives me some useful info for my scope and camera combination here: to summarise my ED80 with FF/FR

Canon 1000D gives 2.30" per pixel

Atik 460ex gives 1.84" per pixel

Atik 414ex gives 2.61" per pixel

4)  What do all these figures mean?

5)  How does 'binning' affect this?

Thanks

[sloz1664]

Hi Peroni,

I use the Atik 460exm and the fov is a good size. I came from the QHY8 pro which has a similar size chip to your 1000D

The 460 is a great ccd camera it is so sensitive compared to the QHY8 Pro so you will see a significant difference with the 1000D

I would certainly get the HaOiii&Sii narrowband filters as you tend to use predominantly Ha followed by Oiii then Sii. Hb I would

purchase at a later date once you have mastered the HaOiiiSii, unless you get an excellent deal on the set.

With the scope you have at present you binning at 1x1 is fine.

cheers

Steve

[kirkster501]

I bow to the greater experience of many others in our learned community  However, I have a 460EX and have found it superb.  Very robust, reliable and noise-free. A joy to use.

[ollypenrice]

You're good to go in my view. 1.84" per pixel is really nice. It means you will get enough light onto each pixel, decent resolution without needing insanely fine guiding or exotically good seeing, and you should get great results. What the figures mean is how much area of sky lands on each pixel. More sky per pixel means more light per pixel. Less sky per pixel means finer resolution - but do you have enough light? And can you guide it? And will the atmospheric seeing let you really capture that detail or will it be blurred out? In my view you can go below 1.84 but 1.84 is a decent compromise. Very decent, especially if you don't have lots of experience.

Binning is not for you if you are doing narrowband at this focal length. If you move to twice the focal length then consider it.

Pure NB imaging is best if you have LP. It makes RGB very difficult.

Attaching the camera to the reducer? I don't know the specific details of this setup but the reducer will have a specified chip distance. Atik give a front of camera to chip distance, add the filterwheel thickness to this and ask your supplier for the adapters and spacers you need.

Olly

[Earl]

Personally id avoid Baader filters I have had 3 sets and all the  Ha had reflections / halos.

[peroni]

...

I would certainly get the HaOiii&Sii narrowband filters as you tend to use predominantly Ha followed by Oiii then Sii. Hb I would

purchase at a later date once you have mastered the HaOiiiSii, unless you get an excellent deal on the set.

...

Personally id avoid Baader filters I have had 3 sets and all the  Ha had reflections / halos.

I was going to get the Baader NB set here which includes Ha(7nm), OIII, SII & Hb for £265 and seems like a good deal.

What NB filters would you recommend?

[peroni]

I bow to the greater experience of many others in our learned community  However, I have a 460EX and have found it superb.  Very robust, reliable and noise-free. A joy to use.

 Thanks for the words of recommendation. I read your post about 314 or 460/490 here and I'll read it again before I finally hit buy. Best to be cautious 

You're good to go in my view. 1.84" per pixel is really nice. It means you will get enough light onto each pixel, decent resolution without needing insanely fine guiding or exotically good seeing, and you should get great results. What the figures mean is how much area of sky lands on each pixel. More sky per pixel means more light per pixel. Less sky per pixel means finer resolution - but do you have enough light? And can you guide it? And will the atmospheric seeing let you really capture that detail or will it be blurred out? In my view you can go below 1.84 but 1.84 is a decent compromise. Very decent, especially if you don't have lots of experience.

Binning is not for you if you are doing narrowband at this focal length. If you move to twice the focal length then consider it.

Pure NB imaging is best if you have LP. It makes RGB very difficult.

Attaching the camera to the reducer? I don't know the specific details of this setup but the reducer will have a specified chip distance. Atik give a front of camera to chip distance, add the filterwheel thickness to this and ask your supplier for the adapters and spacers you need.

And more reassuring words of recommendation. My sky is rural and reasonably dark compared to towns but I still get some sky glow and I can't influence when the moon is around on clear nights.

[Earl]

I was going to get the Baader NB set here which includes Ha(7nm), OIII, SII & Hb for £265 and seems like a good deal.

What NB filters would you recommend?

Having used 3 sets of baaders over a period of time, to make sure they were not from the same batch, all had reflections, I Have not had these with Atrodons, However they cost per filter the same as the baader set, I do have a set of astronomiks in my SX camera im planning on testing out soon (have a few gear issues to sort first.

[peroni]

Having used 3 sets of baaders over a period of time, to make sure they were not from the same batch, all had reflections, I Have not had these with Atrodons, However they cost per filter the same as the baader set, I do have a set of astronomiks in my SX camera im planning on testing out soon (have a few gear issues to sort first.

It looks like you may get what you pay for. Astrodons are way out of my price range, Astronomiks are cheaper but still too much. So Baader will have to meet my poor man's budget 

I'll research Baader's a bit more. Anyone else have an opinion on NB filters?

[ollypenrice]

It looks like you may get what you pay for. Astrodons are way out of my price range, Astronomiks are cheaper but still too much. So Baader will have to meet my poor man's budget 

I'll research Baader's a bit more. Anyone else have an opinion on NB filters?

Yes, I've used three sets of Baader 7Nm Ha without significant halo problems. I had problems with Astronomiks, though. The Baader O111 does give haloes sometimes. I've used the Baaders in Tak FSQ85, FSQ106, Tec140 and ODK14. I'm surpirzed Earl had this problem. I wonder if it could have been internal reflection from somewhere else? I also have an Astrodon 3Nm which gives truly tiny stars and great contrasts but it is hard work because you can hardly every find a star on which you can focus in shot. You have to slew away to a bright one. Bit of a pain!! It's true, though, that in NB you will get a better result from the Astrodons.

I've tried the Astrodon LRGB set three times now and not been convinced that it had any advantage over the Baader set,  which I like very much.

Olly

[peroni]

Yes, I've used three sets of Baader 7Nm Ha without significant halo problems. I had problems with Astronomiks, though. The Baader O111 does give haloes sometimes. I've used the Baaders in Tak FSQ85, FSQ106, Tec140 and ODK14. I'm surpirzed Earl had this problem. I wonder if it could have been internal reflection from somewhere else? I also have an Astrodon 3Nm which gives truly tiny stars and great contrasts but it is hard work because you can hardly every find a star on which you can focus in shot. You have to slew away to a bright one. Bit of a pain!! It's true, though, that in NB you will get a better result from the Astrodons.

I've tried the Astrodon LRGB set three times now and not been convinced that it had any advantage over the Baader set,  which I like very much.

Thanks Olly.

My budget is stretched to the max. so I'll go with the full set of Baader NB filters. Ha, Oiii, Sii, and Hb. The FLO package gives me Hb for only £20 more so I may as well grab it in the set when I can.

So my narrowband imaging covers emission nebula. If I want to try imaging galaxies and clusters, can I use the CCD camera without a filter in place? i.e. the 5 filter wheel has a blank slot (not a clear filter), through which I can take mono images.

[Oddsocks]

I noticed no one had replied to your last question yet.

You can try and image through the empty slot on the filter wheel but as you are imaging with a refractor the stars will be rather bloated because the IR part of the stars spectrum will be focussed outside the visible part of the spectrum, you can't see the IR component by eye but the camera will certainly pick it up.

Then there is also the atmospheric IR back scatter that the camera will see as a slight fog across the entire image, this comes from the moisture content in the atmosphere and is highly variable depending on the weather conditions.

As you are on a tight budget then try it without a filter first and assess how much bloat and fog is present, if it is a problem for you then add the Badder IR/UV block filter to your empty slot.

http://www.firstlightoptics.com/uv-ir-filters/baader-uvir-cut-filter.html

Also remember that the filter (thickness) affects the focus point so if imaging with a narrow band filter in place and then swapping to a no-filter position you will need to refocus the telescope, if you do add a IR/UV filter choose one from the same manufacturers range so that the filter thickness is identical to your NB set then you should not need to refocus between different filters.

[Davey-T]

Hi Peroni, I use the Baader 7nm filter set and as Olly says the only one that I've had bloated stars with is the O111. HA no problems.

Dave

[peroni]

I noticed no one had replied to your last question yet.

You can try and image through the empty slot on the filter wheel but as you are imaging with a refractor the stars will be rather bloated because the IR part of the stars spectrum will be focussed outside the visible part of the spectrum, you can't see the IR component by eye but the camera will certainly pick it up.

Then there is also the atmospheric IR back scatter that the camera will see as a slight fog across the entire image, this comes from the moisture content in the atmosphere and is highly variable depending on the weather conditions.

As you are on a tight budget then try it without a filter first and assess how much bloat and fog is present, if it is a problem for you then add the Badder IR/UV block filter to your empty slot.

http://www.firstlightoptics.com/uv-ir-filters/baader-uvir-cut-filter.html

Also remember that the filter (thickness) affects the focus point so if imaging with a narrow band filter in place and then swapping to a no-filter position you will need to refocus the telescope, if you do add a IR/UV filter choose one from the same manufacturers range so that the filter thickness is identical to your NB set then you should not need to refocus between different filters.

Another filter.

I'd better save this one for birthdays, no way I'd get that past the boss.

Thanks the info.