i have been looking at OAG's and guide cameras for what seems like months..
Are there any brands i should stay away from?
i have been looking at the brightstar OAG, and the orion guide camera, is this a good choice? Im very nervous buying these items without advice from more experienced Astro photographers, any and all advice is greatly appreciated
The brightstar is OK but has a fiddly screw setting, the Celestron radial is good...IMHO I'd go for a QHY5 over the Orion...more "standard" ie ASCOM drivers
The new qhy5LII is about 3 times more sensitive than the old qhy5, gives a far cleaner image, can be used for planetary imaging plus it's smaller than a standard eyepiece, 1.25" format. I just got one myself.
So how does a QHY5L II + Celestron radial guider sound?
is http://www.gamaelectronics.com.au a trustworthy company to order from? I have never heard of them before.
Don't know about the supplier, but the new range of QHY5's looks neat!
The only issue I have is the very small pixels (3.75micron) with no binning option....the QE>75 on the Mono is impressive!
So how does a QHY5L II + Celestron radial guider sound?
is http://www.gamaelectronics.com.au a trustworthy company to order from? I have never heard of them before.
Don't know about the supplier, but the new range of QHY5's looks neat!
The only issue I have is the very small pixels (3.75micron) with no binning option....the QE>75 on the Mono is impressive!
It's the same sensor as is in that group buy webcam but it has a guide port. I'd suggest you don't need big pixels when you're shooting short exposures where well depth isn't an issue. There are quite a few planetary images from it now on the qhy forums but all I've got from it due to weather and changing scopes is a deep space attempt on a cluster. That was shot with the latest beta drivers which give the camera 12bit image support.
The latest PHD has native support for the qhy5II and I believe he is adding native support for the qhy5LII to the next version.
By binning the pixels say 2 x 2 you end up with a 3.75 x 2 = 7.5micon pixel which is much more sensitive. Allows you to better match the guide focal lengths/ plate scale and guide on even fainter star images.
The original (and best!) ST4 - which was used at Siding Spring and other observatories had 13.75 x 16 micron pixels!
The Lodestar guider for comparison has 8.2 x 8.4 micron pixels and the original QHY5, 5.2 micron pixels.
The sensor data sheet shows that binning is available, I guess they just haven't put it into the drivers yet. And if I am reading it right it is saying RGB binning is available on the colour sensor?
Quote:
Digital Binning
By default, the resolution of the output image is the full width and height of the FOV as
defined above. The output resolution can be reduced by digital binning. For RGB and
monochrome mode, this is set by the register R0x3032. For Context A, use bits [1:0], for
Context B, use bits [5:4]. Available settings are:
00 = No binning
01 = Horizontal binning
10 = Horizontal and vertical binning
Binning gives the advantage of reducing noise at the cost of reduced resolution. When
both [horizontal and vertical binning are used, a 2x improvement in SNR is achieved,
therefore improving low light performance
Bayer Space Resampling
All of the pixels in the FOV contribute to the output image in digital binning mode. This
can result in a more pleasing output image with reduced subsampling artifacts. It also
improves low-light performance. For RGB and monochrome mode, the digital binning
factor is set by the register DIGITAL_BINNING (R0x3032). For Context A, use bits [1:0],
for Context B, use bits [5:4]. Available settings are: 00 = No binning; 01 = Horizontal
binning; 10 = Horizontal and vertical binning. For RGB mode, resampling can be
enabled by setting of register 0x306E[4] = 1.
I thought true binning is performed on the sensor. That data sheet extract seems to say you just need to flick a bit in a register on the sensor to change the mode. It's typical qhy really, they push products out the door and then work on the software
I seem to be seeing new drivers and capture software for it on their website every time I look. They now have turned on a 12bit HDR function for it so they appear to be turning up the planetary options for it.
Hi,
The qhy5-2 has a higher sensitivity near the 400nm as opposed to the qhy5 at around 550 and lodestar at over 600nm
Would this affect sensitivity as a guidecam?
The costar is more affordable, slightly less sensitive than the lodestar and is a good contender
Would the celestron radial be viable for newts as well?
I will try binning with the qhy5. Not sure where the option is though
You'll probably find backfocus issues with the corrector on a newt using that OAG. I've had to go to one of these low profile jobs to get around those issues. I'm still waiting for adapters to get it all working.
I see the binning options in maxim, don't see them in phd.
I personally went with the TSOAG9 from Teleskop Express, I think they still have a few second hand stock left. I got it second hand from their site for $190AUD, which is a little steep compared to the others but it's only 9mm long which allows for much more flexibility later on down the track with correctors and flatenners (Like using a CCD & Filterwheel or a DSLR with the common backfocus of 55mm). Plus it has a whole host of adapters available for it so you can really customise it if needed. I decided I'd rather spend the extra and future proof
In terms of guidecam its completely dependent on what you're imaging with. If it's a f/5 then the new QHY5-II or the QHY5L-II would be just fine as it's plenty sensitive. I have a QHY5-II on loan for review, yet to a clear night but already obvious its alot cleaner than my older QHY5 which I sold. Stay away from the Orion SSAG, its more expensive and some features are disabled. Teleskop also sell the 'ALccd' brand, which are clones of QHY but cheaper.
The sensor data sheet shows that binning is available, I guess they just haven't put it into the drivers yet. And if I am reading it right it is saying RGB binning is available on the colour sensor?
The QHY-5 II datasheet says it supports 2x2 binning.
The QHY-5L II datasheet says it does not support binning, but does not say if that applies to both colour and mono versions.
