Move to CCD, please help!

[PhotoGav]

Ouch - that is a stunning image Sara, thank you for posting the link, I really enjoyed looking around that one. And, no, it certainly isn't flat. But then, it's taken with a refractor, which would support the earlier thoughts about scope type rather than chip.

(Some fantastic images on your flickr page - I'm meant to be working, but just enjoyed a good meander through the heavens... Thank you!)

[GuillermoBarrancos]

PS. Sara. Have you already decided which camera and sensor you going for now?

As you seem to be focussed on long focal imaging atm, I guess you go for one of the KODAK sensors with larger pixels?

[ollypenrice]

The quantum mechanical description of  light passing through telescopes dispenses entirely with the idea that the photons arriving at the chip are those which entered the top of the tube. This applies equally to reflectors and refractors. I don't believe that reflector/refractor choice will have any effect on apparent depth. The only thing I can think of is the gamut of colours made available by the well depth and even then I'm not for a moment saying I'm convinced. I'm open to considering the issue though. This effect, if it exists, will probably be more apparent in RGB than narrowband since the eye has evolved to respond to natural colour. All this is getting so far from the testable as to be pretty dodgy in my view!

Regarding the filters, I processed two images with the Astrodon filters and can't say I liked them, really. (A very good thing because they ain't cheap!) While many of the best imagers in the world swear by them I had a strange feeling of two dimensionality while working on the data. Totally subjective and possibly nonsense but I had this feeling of red-blue bipolarity without the green doing its pecualiar thing. I say pecualiar because we rarely want to see green per se, but it has a distinct effect on the reds and blues, giving them a nice range of possibilities. I couldn't tease much variety out of either red or blue with the Astrodons but it might just be unfamiliarity or something existing only in my head!

I like the Baader interference colour set.

Olly

[swag72]

Got a few ideas in the bag thanks Guillermo - It has to work between the short focal length of the Tak and the 2350mm focal length of the SCT - Not too much required then!!!

Sorry Gav - didn't meant to hijack this thread, just wanted to throw out an image that is taken by the same camera as took one that seem to be coming across as 'flat' - Probably proves that it's not the camera after all?

[PhotoGav]

Olly - yes a very dodgy hypothesis, grounded in no science whatsoever! Thank you for your opinions on the filters.

Sara - far from hijacked, most definitely adding to the discussion and I thank you for that. When you have formulated your opinions on what camera will be better than the 460EX, I am very interested to hear!

As for depth of image... I think (and what do I know) that depth comes from more data and flat images are generally from a lack of data.

[GuillermoBarrancos]

The quantum mechanical description of  light passing through telescopes dispenses entirely with the idea that the photons arriving at the chip are those which entered the top of the tube. This applies equally to reflectors and refractors. I don't believe that reflector/refractor choice will have any effect on apparent depth. The only thing I can think of is the gamut of colours made available by the well depth and even then I'm not for a moment saying I'm convinced. I'm open to considering the issue though. This effect, if it exists, will probably be more apparent in RGB than narrowband since the eye has evolved to respond to natural colour. All this is getting so far from the testable as to be pretty dodgy in my view!

Regarding the filters, I processed two images with the Astrodon filters and can't say I liked them, really. (A very good thing because they ain't cheap!) While many of the best imagers in the world swear by them I had a strange feeling of two dimensionality while working on the data. Totally subjective and possibly nonsense but I had this feeling of red-blue bipolarity without the green doing its pecualiar thing. I say pecualiar because we rarely want to see green per se, but it has a distinct effect on the reds and blues, giving them a nice range of possibilities. I couldn't tease much variety out of either red or blue with the Astrodons but it might just be unfamiliarity or something existing only in my head!

I like the Baader interference colour set.

Olly

Interesting Points. It´s all theory taken from ongoing discussions regarding refractors vs reflectors.

As the Atik 460EXM has a relative small pixel size, it might in the end also be something simple as sampling rate and that this sensor might not be at it´s best on long focal lengths.

Firing up the arcsec pixel ratio debate again.

I guess it all comes down to each their own personal perception of the image.

[mikeyscope]

Olly

What series Astrodon filters was used with the 460 to take the globular image ... E-series ...OR the I-series?

Mike

[PhotoGav]

Hello again folks, my research has led me to be seriously considering the Atik 383L+ with EFW2. This seems to be the one that gives me quality, FOV and value. My question is what size filters should I go for: 1.25" or 36mm? I will be using the camera with the ED80 with reducer & edgeHD 8" with and without reducer.

[swag72]

Gav, I would seriously take a look at the QSI range - 583 or 683. A litte more expensive, but in my opinion, worth the extra.

[cfpendock]

Hello Gav.  I am not an expert with your optics, but if you go for 1.25" filters, is it possible you will experience some vignetting, especially when using the reducer with the ED80?  

Chris

[PhotoGav]

Gav, I would seriously take a look at the QSI range - 583 or 683. A litte more expensive, but in my opinion, worth the extra.

Sara, that is exactly the alternative, but comes at around a grand more expensive... Is it really that much better? If so, what is it that is so much better... Will I really notice a difference? £2.5k is already quite a chunk for a hobby! Interested to hear your further opinions.

Hello Gav.  I am not an expert with your optics, but if you go for 1.25" filters, is it possible you will experience some vignetting, especially when using the reducer with the ED80?

That's exactly the reason for my question! Not sure if the smaller filters will give me trouble...

[swag72]

Sara, that is exactly the alternative, but comes at around a grand more expensive... Is it really that much better? If so, what is it that is so much better... Will I really notice a difference? £2.5k is already quite a chunk for a hobby! Interested to hear your further opinions.

Here's my thinking Gav - Get one with an integrated filter wheel and OAG - That way you need never worry about OAG spacing ever again. It's an absolute gift. That way, changing over from one scope /  imaging train to another is about as easy as it can get.

If you speak with IKI you can talk about whether the 683 / 583 will work with 1.25" filters. I'm sure that I read on here comments that if the filter wheel was close enough to the sensor you could happily use 1.25" with this sensor. I'm sure that IKI can confirm either way.

Build quality of the QSI is superb. In my opinion it is head and shoulders above the Atik. It's absolutely solidly built and feels like an utter quality product.

Cooling - Something very personal to my heart of course living in Spain - But the cooling on the QSI is unbelievable. When I first plugged it in, the temperature was showing as 28 degrees. It took me to -10 degrees in seconds, using only 50% of the cooler power and so quietly I couldn't even hear it. Gone are the days of the loud Atik fan in my ear, this is ridiculously quiet and efficiency is unbelievable. Now while you won't need the cooling so much, I still reckon with that Kodak sensor that you will do well to cool as low as you can.

Ease of use - As per the Atik, the drivers loaded into Maxim and that was that.

Cable connectivity - Much better on the QSI. The cables come out from the bottom, so no danger of snagging them or pulling them out.

Now are these things worth the extra ££'s? Only you can decide. They certainly were to me.

[cfpendock]

Well, I originally went for 1.25"for my refractor, and always had to use flats to get rid of the vignetting (never very satisfactory in my view) so now I also have 36mm.  Unless you are sure, for around £100 extra for the 36mm it maybe a worthwhile insurance.  Especially if you change your rig at some time in the future....

Chris

[PhotoGav]

Sara, sounds like you have a tasty new QSI on your rig! Congrats. Which one? Many thanks for your full response, it is very convincing and certainly makes a great deal of sense. I will have to seriously look at the finance side of this again...

Chris, thanks for that. Looks like the larger filters will be the way forward, but as Sara suggests, I will ask the question to IKI.

Thanks both.

Sent from my iPhone using Tapatalk

[ollypenrice]

Olly

What series Astrodon filters was used with the 460 to take the globular image ... E-series ...OR the I-series?

Mike

Sorry, Mike, I can't remember. It was a while ago and our guest had bought his set second hand.

Olly