Quote:
Originally Posted by Slawomir
Hi Colin,
I would pick Atik One 9.0 as an integrated kit (with FW and OAG), or, if budget permits, the SX camera, as you could later on add their dedicated Active Optics unit.
ICX 814 from my experience is a very nice sensor, I am sure you will be very happy with any camera you decide to buy from your list.
EDIT: If you are not planning to keep your current camera, then there is an option of selling your current filters or swapping them for smaller ones that would fit a QSI 690 WSG-8, 8 position filter wheel can be quite useful if you would like to add RGB stars/data to your narrowband images  |
The Atik One does look like a nice camera but it doesn't allow for 36mm unmounted filters. I am looking at selling the camera but I would prefer to keep the filters. I could effectively swap the 36mm for a set of brand new 1.25" ones but it does constitute a relatively large monetary drop that is quite unneeded. I currently have set of Astrodon LRGB & Ha OIII SII (all 3nm) so I do want to get a 7x36mm filter wheel, like the one I've already got
Quote:
Originally Posted by billdan
Hi Colin,
If you want the ICX 814 chip then the QHY24 is the one to go with.
The QHY23 uses the ICX 694 chip.
Physically they are both the same size chip 14.6 x 12.8mm, the 694 chip is 2838 x 2224 with 4.54 micron pixels, the 814 chip is 3468 x 2728 with 3.69 micron pixels.
Well depth may be an issue with the 814, only 15,000e vs 20,000e.
Regards
Bill
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As far as I am aware there is no QHY24. QHY22 is the 694 and QHY23 is the 814, QHY21 is the smaller QHY22 variant. The ICX 694 has a 18,500 e- well depth. Given the smaller pixel size, the ICX814 has 0.66x less surface area which therefore means 0.66x the overall flux per pixel given that they have near identical QE. As the ICX814 only has 0.8x of the well depth, it should take up to ~22% longer for the ICX814 to hit full well depth than the ICX694. Someone can correct me if I am wrong there. Well depth shouldn't be an issue.
From what I can tell the biggest issue is actually going to be in read noise between the two sensors. When comparing the FLI Microline versions, the 814 has 2e- RMS and the 694 has 3e- RMS. This means that even with the smaller pixels (each pixel takes longer to collect the same number of photons), it still reaches read noise limited ~50% quicker than the 694 version due to a lower read noise.
Taking the QHY22 which typically seems to get around 4.5e-. As long as the QHY22 has a read noise 3.65e- or below, it will reach read noise limited as quickly or faster. One of the QHY23 results I have seen is at ~3.3 e-, although there isn't enough of them out there to test whether this is a normal range or unusually low.