First light AP RHA 305 F3.8 REPRO

gregbradley · #1 03-05-2015, 01:04 PM

I spent several days at my dark site using this new scope. Its not fully setup yet as I am waiting on some adapters to fit a FLI Atlas focuser and a spare part for the filter wheel.

But I was able to focus manually in the meantime (it tricky as the critical focus zone is very small compared to other scopes I have used but it does snap to focus and the graph spikes suddenly, fine adjustments though are very hard to do with just the microfocuser).

Also there was some tilt that showed up in one corner with the Proline (may be from the filter wheel) that has to be corrected.

Tracking from the mount was not as good as it was last with the lighter AP140 so again an updated Polar Alignment and TPoint model should help there.

Having said all that the results were very good. This a small crop of a much wider field. The Proline is somewhat undersampled so I may reprocess this one and use Drizzle integration to round out some of the undersampled stars (not really visible unless you really zoom in).

I am impressed by this scope. It also works well with the small pixelled Sony camera (perhaps even better). Tilt tip sort out using CCDInspector and adjustments to the tilt/tip adapter is on the agenda.

This is only a 3 hours and 15 minute image (95 Luminance 40 mins RGB each).

Ideally a 10 hour image on this scope and these cameras should be very deep. So given reasonable weather that will be the type of image I will be going for 8-12 hours on a typical target. F3.8 is a blast that way. Exact focus, perfect squareness of components, exact autoguiding are the things that need to be done on this setup for it all to work and take advantage of the sharp optics.

Also on this image I did not have the fans going so perhaps that makes a difference as well. Its all a learning curve and its a good start.

I took an LRGB image of 5 minutes each filter and I was surprised at how deep and detailed the resulting image of 20 minutes is. This is why I wanted this scope to be able to take advantage of my dark skies but not being remotely controlled I need to get a bright image fast. I also have a galaxy image that I like and I took a Ha image that I also liked and again its pretty deep for only a 3 x 20minute 1x1 binned image.

I notice on this image there are some little diffraction spikes on some brighter stars, that seems to be from the microlenses. I don't see them on the Trius images.

This image is about 1/3rd of the full image so the Proline is not the best choice for a galaxy image and shows how sharp the optics are that they stand up to that much of a crop.

Taken from my dark site observatory in Bigga NSW.

http://www.pbase.com/gregbradley/ima...22874/original

http://www.pbase.com/gregbradley/image/159922874/large

Photos of the A RHA 305mm F3.8 setup:

http://www.pbase.com/gregbradley/image/159928675/large

http://www.pbase.com/gregbradley/image/159928686/large

And of course an Eta Carina 1st light test image of only 20 minutes total (LRGB 5mins each). Keep in mind there is no Ha exposure in this image even though it looks like there is:

http://www.pbase.com/image/159931632/large

12 inch aperture F3.8 as Mike knows gets a lot of signal fast. The quickest imaging scope I have ever used.

Greg.

Stevec35 (Steve) · #2 03-05-2015, 01:12 PM

Well to say the least that looks extremely promising Greg! Congratulations on your new acquisition.

Cheers

Steve

gregbradley · #3 03-05-2015, 01:20 PM

Quote:

Originally Posted by Stevec35

Well to say the least that looks extremely promising Greg! Congratulations on your new acquisition.

Cheers

Steve

Thanks Steve. There's always a learning curve with new gear but as you say its very promising.

Greg.

RickS (Rick) · #4 03-05-2015, 01:20 PM

As expected, the RH certainly sucks down the photons, Greg!

gregbradley · #5 03-05-2015, 01:30 PM

Quote:

Originally Posted by RickS

As expected, the RH certainly sucks down the photons, Greg!

It sure does. It doubles as an excellent widefield scope but also with a small chip camera an excellent galaxy imaging scope much like your Ceravolo. I have a galaxy image I'll post later which I was happy with especially considering the exposure time (5 hours 20 minutes).

Greg.

Slawomir (Suavi) · #6 03-05-2015, 02:43 PM

Nice one Greg, I like how the halo around the Galaxy shows up very clearly.

It surely will be an exciting journey fine tuning the rig, and it will only add to your experience as an astrophotographer.

gregbradley · #7 03-05-2015, 03:12 PM

Quote:

Originally Posted by Slawomir

Nice one Greg, I like how the halo around the Galaxy shows up very clearly.

It surely will be an exciting journey fine tuning the rig, and it will only add to your experience as an astrophotographer.

Thanks Slawomir.

Ideally it would be longer exposure time. The Trius 694 is better suited for galaxies as it is a bit undersampled. I had the Proline setup and it was running so I let it go for a while. A 1/4 moon was still up for some of this as well.

Greg.

omegacrux (David) · #8 03-05-2015, 04:20 PM

Been following your progress
Sweet scope & good looking first light

David

OzEclipse (Joe Cali) · #9 03-05-2015, 04:21 PM

Greg,

Very nice image especially given you are still in shakedown mode, and fast setup too. A friend of mine bought a 12" Planewave CDK a few years ago. Took him more than a year to iron all the bugs out of it before he got first light. In the end, Planewave sent him a swag of new parts and he had to do a major remachine at the back end. If I recall, the focusser was not concentric or something.

You must really be looking forward to this coming winter.

I hope you realize you have just guaranteed all of us in NSW/ACT of having the motherload of cloudy nights all winter.
Look forward to seeing more of your work.

Joe

gregbradley · #10 03-05-2015, 05:11 PM

Quote:

Originally Posted by omegacrux

Been following your progress
Sweet scope & good looking first light

David

Thanks David.

Quote:

Originally Posted by OzEclipse

Greg,

Very nice image especially given you are still in shakedown mode, and fast setup too. A friend of mine bought a 12" Planewave CDK a few years ago. Took him more than a year to iron all the bugs out of it before he got first light. In the end, Planewave sent him a swag of new parts and he had to do a major remachine at the back end. If I recall, the focusser was not concentric or something.

You must really be looking forward to this coming winter.

I hope you realize you have just guaranteed all of us in NSW/ACT of having the motherload of cloudy nights all winter.
Look forward to seeing more of your work.

Joe

Ouch on the Planewave. My CDK17 has been trouble free except for a bit of off axis bright star streaks that got corrected with some free baffles they sent me.

I am hoping the heavy rain the purchase induced has already subsided with that heavy rain about a week ago. But one can't be certain when AP telescopes have been purchased!

I should have a steady stream of images given the fast F3.8 and renewed interest a new scope often brings.

Greg.

strongmanmike (Michael) · #11 03-05-2015, 06:38 PM

Hmm? Meeeah..well,the scope sure looks beeeautiful! But not sure the first two images are showing us what it should be capable of Greg

As you say you have some more shaking down to do and have some better adapters coming, so I look forward to what I am sure will eventuate

Mike

gregbradley · #12 03-05-2015, 07:26 PM

Quote:

Originally Posted by strongmanmike

Hmm? Meeeah..well,the scope sure looks beeeautiful! But not sure the first two images are showing us what it should be capable of Greg

As you say you have some more shaking down to do and have some better adapters coming, so I look forward to what I am sure will eventuate

Mike

First 2? Its a shakedown cruise and for 3 hours its not bad. Ideally I'd use the Proline for widefield shots I think.

Greg.

strongmanmike (Michael) · #13 03-05-2015, 08:37 PM

Quote:

Originally Posted by gregbradley

First 2? Its a shakedown cruise and for 3 hours its not bad. Ideally I'd use the Proline for widefield shots I think.

Greg.

NGC 6744

oh of course, shaking down takes time I know

yes the Proline on the Honders will rock for the bigger things

Mike

LewisM · #14 03-05-2015, 08:47 PM

The reflecting refractor delivers the goods!

Exceptional.

Peter Ward · #15 03-05-2015, 09:17 PM

Not bad, but sorry no cigar...a galaxy would not have been my first choice...

but...you go after what *you* like, after all, it's your scope!

It took me about 6 months (of spotty efforts) to get the Honders, camera, CFW and AO lined up to within a few microns...in a perverse way, you'll find the optics are so good, they'll let you know often enough when something is off.

It really sings when you get the orthogonality of the focal plane sorted...particularly with a 16803 chip.

But isn't it great to have first light through such a special instrument!

Bon voyage!

P.S.

We still need to have a conversation about the weather

alpal · #16 03-05-2015, 09:30 PM

Hi Greg,
that's a great first light & I can't wait to see you do a nebula with that scope.

cheers
Allan

gregbradley · #17 03-05-2015, 10:08 PM

Quote:

Originally Posted by strongmanmike

NGC 6744

oh of course, shaking down takes time I know

yes the Proline on the Honders will rock for the bigger things

Mike

Right.

Quote:

Originally Posted by LewisM

The reflecting refractor delivers the goods!

Exceptional.

Thanks Lewis. Its a start and promising better things.

Quote:

Originally Posted by Peter Ward

Not bad, but sorry no cigar...a galaxy would not have been my first choice...

but...you go after what *you* like, after all, it's your scope!

It took me about 6 months (of spotty efforts) to get the Honders, camera, CFW and AO lined up to within a few microns...in a perverse way, you'll find the optics are so good, they'll let you know often enough when something is off.

It really sings when you get the orthogonality of the focal plane sorted...particularly with a 16803 chip.

But isn't it great to have first light through such a special instrument!

Bon voyage!

P.S.

We still need to have a conversation about the weather

Exactly right Peter. That is what I have noticed so far. Not quite square and it shows up. Its reassuring to hear that and confirms what I thought.

Yes a galaxy wasn't what I intended either. But my filter wheel needs repair and I am waiting on a part. It misaligns after a few filter changes losing more and more of the FOV as it does. So I did tend to concentrate on narrower targets because of that. I should have it fixed this next week as the part is on its way.

This image isn't meant to be the best it can do but an output from it that starts the refinement process. Which is fun in itself really. Its a fiddly sort of pursuit.

Sorry about the weather.

Greg.

gregbradley · #18 03-05-2015, 10:09 PM

Quote:

Originally Posted by alpal

Hi Greg,
that's a great first light & I can't wait to see you do a nebula with that scope.

cheers
Allan

Thanks Allan.

I have done a quick image of a couple. The weather was clear for most of 2 nights one of which was a late clearing. The 3rd night it was clear but very windy so no go.

The weather forecast is improving so more time to work on it.

Greg.

Paul Haese · #19 03-05-2015, 10:27 PM

Bit of a shake down yet but you're well on your way Greg. I look forward to your updates.

gregbradley · #20 03-05-2015, 10:28 PM

Here's the 1st test image I took with the Honders.

I was blown away by the depth of this quick exposure. This is only a single 5 minute exposure of LRGB for a total of 20mins yet it shows a fair bit of detail.

It was good to see the snap to focus when its close even if touchy manually.

More wide field Proline images next time once my filter wheel is fixed
and the filters don't progressively go out of alignment costing more and more field of view.

Eta Carina naturally. Keep in mind there is no Ha in this exposure even though its picking a lot of it up.

http://www.pbase.com/image/159931632/large

Greg.