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Why do some consider Hyperstar a 'crude' platform?

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#76 Starhawk

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Posted 27 April 2013 - 04:15 PM

You've got some pretty pictures, Mike. It seems you have been holding out on us.

Of course, that implies what this is all about is pointing out one can out-resolve a $3000 CPC 1100 11" SCT taking 30 second exposures using a $900 hyperstar system with 89 minutes of exposure with as modest a setup as a $66,700 10" TMB APO on a $27,000 AP3600.

I'm not sure this was a subtle insight any of us had missed and needed to have explained. We could have also gone down the road of pointing out how Yuri's $50,000 f/1.44 300mm astrograph would also outperform hyperstar.

-Rich

#77 jrcrilly

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Posted 27 April 2013 - 04:36 PM

With the same camera they would both produce the same image scale.


True. Most folks tend to choose different cameras for Hyperstar than they would for other applications, though. A mono camera that would be somewhat undersampled at that focal length would be much more undersampled if replaced with a OSC camera using the same chip - and OSC cameras are the Hyperstar norm for various reasons. It costs more to own a widefield platform that doesn't care what camera one uses - but one shouldn't understate the benefits of having that flexibility. HS can be an acceptable compromise but it will always be a compromise.

#78 Alph

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Posted 27 April 2013 - 05:05 PM

I have RAW data. What would you like to see?

-Rich

Sure. Raw FITS images are always welcomed.

#79 Starhawk

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Posted 27 April 2013 - 05:17 PM

MyRAW images aren't in FITS format. The camera produces 14 bit images in a proprietary format. I can export stacks as FITS, but that obviously not a raw image anymore.

-Rich

#80 David Pavlich

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Posted 27 April 2013 - 05:49 PM

[quote name="Starhawk"]

In the end, the real drawbacks are camera size (which appears to be losing relevance weekly), and back focus distance to accommodate filter wheels and such.

-Rich

[quote[/quote]

The QSI583 with the 36mm filters installed would work quite well on a C11 or C14. It's not much different from a DSLR in size. So, there is a terrific way to do LRGB if you want to spend the bucks on the camera since the 8300 class chip works so well with short FL.

David

#81 Phil Hosey

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Posted 27 April 2013 - 06:19 PM

There are a number of cameras that have come out recently that have small pixels that will get you around 1.5"/pixel and many of these are even shaped with Hyperstar in mind. There is also the filter drawer system that can be used to swap out filters making monochrome imaging with Hyperstar much more doable. I am plannig at some point to get one of the new the mono cameras with the Sony 674 or 694 chips so I can do some narrowband with the Hyperstar. Until then I'll continue to use my T2i which gives me 1.58"/pixel

#82 wolfman_4_ever

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Posted 27 April 2013 - 06:51 PM

Hi Phil and others.

I have the starizona filter drawer for hyperstar and the 694. The SX 894 would give you a pixel size of 1.36 The 694 is 1.67. I have never used the hyperstar or filter drawer.. lol. My 127is gives me a FOV about the same when using said h694.. aperture/speed would be the difference.... guess i'll have to do an experiment one of these days..

OSC only in hyperstar is no longer your only option.

USB wireless/bluetooth 3.0, etc dongles and sticks are becoming more widespread and faster.. Soon you'll only have that darn power wire hanging down..

Can I get some longer distance wireless power please :p

#83 frolinmod

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Posted 27 April 2013 - 07:46 PM

We only need to transmit that power from the edge of the OTA to the camera hanging off the Hyperstar lens. Perhaps 12 inches. If only!

#84 mmalik

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Posted 27 April 2013 - 07:56 PM

It seems to me the issue Jared is talking about is in regard to image scale only.


For a given sensor image scale would translate into resolution one is going to get. With the same aperture say C8 one is going to get less resolution with HyperStar (being wide FOV) than without HyperStar (being narrow FOV) using the same sensor. Regards

#85 mmalik

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Posted 27 April 2013 - 08:12 PM

I'm not sure this was a subtle insight any of us had missed and needed to have explained.


Not at all Rich; was not implying that. What I have been implying, Jared I think has taken it a step further in explaining pros and cons of the HyperStar system even more eloquently. Regards

#86 Phil Hosey

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Posted 27 April 2013 - 08:34 PM

It seems to me the issue Jared is talking about is in regard to image scale only.


For a given sensor image scale would translate into resolution one is going to get. With the same aperture say C8 one is going to get less resolution with HyperStar (being wide FOV) than without HyperStar (being narrow FOV) using the same sensor. Regards


Yes, I know that, but you seem to imply that there is something wrong with Hyperstar being fast other than the affect it has on the focal length. Unless that is what you meant all along in which case it is obvious. But a Hyperstar C11 at 560mm is basically the same as an NP101 (540mm) as far as image scale with the same sensor, but the Hyperstar is faster.

I guess I still don't quite understand the point you are trying to make. If all you are saying is that because the focal length of an f/2 Hyperstar system is short compared to a C8 at f/10 or f/7, then yes, this is purely a function of image scale and image scale affects resolution, but being 560mm is nothing unique to Hyperstar, there are plenty of other optical configurations that would put one in that focal length range.

#87 mmalik

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Posted 27 April 2013 - 09:11 PM

I guess I still don't quite understand the point you are trying to make.


Besides my main reservation HyperStar being on obstructed SCT/'not so solidly put together platform', I guess another way of looking at it would be one taking casual, less resolved pics in lesser amount of time on HyperStar than one taking sophisticated, more resolved pics in bit more time on unobstructed refractors. Regards

#88 jrcrilly

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Posted 27 April 2013 - 09:21 PM

Besides my main reservation HyperStar being on obstructed SCT/'not so solidly put together platform', I guess another way of looking at it would be one taking casual, less resolved pics in lesser amount of time on HyperStar than one taking sophisticated, more resolved pics in bit more time on unobstructed refractors. Regards


So you don't approve of the Riccardi-Honders or Epsilon either? I've never heard them relegated to casual use before.

#89 milby

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Posted 27 April 2013 - 10:24 PM

Five pages of facts and theory demonstrating the ingenuity and facility of the HS platform and refuting the unfounded biases of the original poster. And it turns out he just doesn't like it because it's "casual."

To quote the 21st Century philosopher Katt Williams, "Haters gonna hate. It's what they do."

#90 Starhawk

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Posted 28 April 2013 - 01:26 AM

Milby, I think you've got it. It's pretty clear the arc in tech development favors this system. And that annoys some people for specific reasons they don't want to voice. So, here we are with a thread with the final complaint boiling down to, "I just don't like it."

Sounds like the time has come to wrap it up if you ask me.

-Rich

#91 Phil Hosey

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Posted 28 April 2013 - 02:08 AM

Five pages of facts and theory demonstrating the ingenuity and facility of the HS platform and refuting the unfounded biases of the original poster. And it turns out he just doesn't like it because it's "casual."

To quote the 21st Century philosopher Katt Williams, "Haters gonna hate. It's what they do."


Just for the record, I'm the original poster. I like SCTs and I like Hyperstar. Oh yea, and sometimes I like to be casual. I don't have any unfounded biases for or against it. Oh wait, maybe I do.. I just like it. I think you may be referring to the one who prompted me to start this thread in the first place.

#92 mmalik

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Posted 28 April 2013 - 03:41 AM

This has been a great discussion I think; I am sure there is lot for everyone to take away from this. I surely feel more informed than before about HyperStar and it's capabilities. Thanks to all who contributed, especially Phil for starting the discussion. Regards

#93 telfish

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Posted 28 April 2013 - 07:53 AM

I love my Hyperstar "crude" or not.

The End.

#94 milby

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Posted 28 April 2013 - 08:24 AM

Sorry, Phil. I was, indeed, referring to the author of the "casual" comment.

#95 Starhawk

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Posted 28 April 2013 - 09:40 AM

Seriously Mike, with a rig at the level you're using, you should just get a hyperstar SCT and play with it then draw your own conclusions.

What's completely missing from this discussion is what it's like to use hyperstar in practice. You go out, get aligned, and then swap the secondary for hyperstar and hook up the camera. After that, the biggest problem is coming up with more objects to photograph and choosing camera orientations for the image capture. I

t's just a radically different experience from setting up an autoguider and spending several nights working on just one object.

-Rich

#96 milby

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Posted 28 April 2013 - 10:09 AM

It's also possible to align using the Hyperstar.

#97 Starhawk

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Posted 28 April 2013 - 11:08 AM

This is true. Especially in the case of a permanent mount, there's little reason to be setting up and taking down a hyperstar system. Come to think of it, that's what what the ISS installation is like.

-Rich

#98 rmollise

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Posted 28 April 2013 - 12:01 PM

I guess I still don't quite understand the point you are trying to make.


Besides my main reservation HyperStar being on obstructed SCT/'not so solidly put together platform', I guess another way of looking at it would be one taking casual, less resolved pics in lesser amount of time on HyperStar than one taking sophisticated, more resolved pics in bit more time on unobstructed refractors. Regards


Have you TRIED Hyperstar/Fastar or watched somebody using it? As I said in my post above, most of your assumptions are incorrect. If you don't want to image at this focal ratio, that's fine. It doesn't fit in with everybody's goals, but your fears and reservations are incorrect. It works just fine. ;)

#99 JMW

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Posted 28 April 2013 - 11:37 PM

Just ordered a Hyperstar III lens for my C11 EdgeHD. Picked up a used Starlight Xpress 26C to use with it. Do most people auto guide with Hyperstar? I will have it mounted on a AP900GTO and PEC does pretty well. I have done 10 minute unguided with a SV115T at 800mm and got nice round stars.

I figure sky glow will be quickly be my limit when imaging at my home. Hopefully will be able to go deeper when I take the rig to the GSSP in July. What's the typical exposure when doing one shot color a f/2 in a light polluted area?

#100 Starhawk

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Posted 29 April 2013 - 12:45 AM

You can expect to be sky limited within a minute. I've been curious myself about what can be done with really long exposures, but it would require remarkably dark skies to find out.

-Rich






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