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Guiding Guidance

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#1 Dave Lee

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Posted 10 July 2013 - 04:52 PM

I am sizing up a move to guided AP (currently operating unguided using shorter prime focus DSLR lenses). The target here would most likely be an older 8" Meade f10 SCT (focal reduced to f6.3) on an older G11 mount. I am leaning toward a separate guide scope but have not ruled out an OAG.

The cameras in the running are the Orion SSAG and the QHY5 - based on price and the fact that they directly support the required ST4 output. I assume that I would be using PHD, BTW.

Any thoughts on why I should chose one or the other - or suggestions on alternatives here?

THanks.

dave

#2 shawnhar

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Posted 10 July 2013 - 05:29 PM

I have heard OAG's are the solution to issues with flex between the guide scope and imaging scope, but I am running an 80mm short tube with a DSI using rings and a rail and lovin it so far. OAG can make it hard to locate a guide star as well.

#3 palmer570

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Posted 10 July 2013 - 05:48 PM

I was in the same position a week or so ago.

I like that the QHY5 can be used as a guider, lunar/planetary imager, or a allsky cam(with the additional lenses). More sensitive?

I can be wrong but I believe it was PHD that is just starting to support the QHY5, could have been another program I was cross checking, I forget.

I decided on the SSAG instead because of cost, in stock locally, and I will probably never use it as a allsky or imager.

#4 Jeff2011

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Posted 10 July 2013 - 05:53 PM

I have a QHY5L-II mono and am extremely happy with it. Someone on CN had suggested it to me over the SSAG and I am thankful. Do not get the color QHY because the mono is more sensitive. My imaging scopes do not have long focal lengths, so I use the Orion 50MM mini deluxe for a guide scope.

#5 D_talley

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Posted 10 July 2013 - 06:06 PM

I currently use the QHY5 with a 102mm scope as a guider with PHD. But I am looking to buy the more sensitive Lodestar guider instead.

#6 Dave Lee

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Posted 10 July 2013 - 06:20 PM

Dwight, I'm curious as to what factors are driving you to something besides the QHY5 (and what your setup is, including the fl of your guidescope).

Thanks.

dave

#7 DaemonGPF

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Posted 10 July 2013 - 06:32 PM

The QHY-5 and the SSAG are the same camera. Difference being proprietary firmware in the SSAG which limits it to guiding. The QHY-5 can be multi-purposed. The mono is quite sensitive. I've owned two of them over the years.

I recently switched to an ASI120MM. It is EXTREMELY sensitive with very high QE, and for an inexpensive price. Might want to take a look at them.

#8 freestar8n

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Posted 10 July 2013 - 06:40 PM

There is the older QHY5 and the new QHY5L-II, which has video drivers, an st4 port, and is supported for video guiding by my software, MetaGuide. It is small, about the size of a lodestar and 1.25" diameter, and very sensitive. Good for guiding, video collimation, video finder - all kinds of things.

I think it is the same chip as in the ASI120MM, for the mono version anyway.

Frank

#9 Wmacky

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Posted 10 July 2013 - 08:17 PM

The QHY-5 and the SSAG are the same camera. Difference being proprietary firmware in the SSAG which limits it to guiding. The QHY-5 can be multi-purposed. The mono is quite sensitive. I've owned two of them over the years.

Josh, Have you had a chance to compare sensitivity between the MM, and MC version of the ASI cams?

I recently switched to an ASI120MM. It is EXTREMELY sensitive with very high QE, and for an inexpensive price. Might want to take a look at them.



#10 DaemonGPF

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Posted 10 July 2013 - 08:50 PM

I haven't had a chance to do a comparison yet, as I've been busy rebuilding my mount. However, the MC was quite good enough to autoguide in my red zone, unfiltered, facing into the light pollution source (DENVER). I pointed it towards M106 where there's not really any bright stars and I was able to pick up several.

#11 Cliff Hipsher

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Posted 11 July 2013 - 03:18 PM

I'm going with an OAG (actually a Celestron Radial Guider #94176).

I had considered a separate guide scope and camera, but I ran into cost and balance issues.

When I compared the cost of the scope, rings, and dovetail/mounting bar and counter weight(s) to a OAG, it was a no brainer.






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