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Old 02-07-2022, 04:02 PM
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john guy (John)
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can anyone advise on a good deep sky camera for a Meade 14'' sct
cheers JG
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Old 02-07-2022, 04:54 PM
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Bassnut (Fred)
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Thats at 3556mm FL!. get the largest pixel size you can and not too large a sensor at a guess, think a full 35mm frame might be a problem.
ZWO ASI482mc at $579 , 5.8um pixel size and .34 arc sec (oversampled) Res pops up, but its colour. Most CMOS cams will be massively oversampled at this FL, but always binning would be an easy option. If your keen on really long exposure deep sky, look for a S/H CCD with large pixels.
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Old 02-07-2022, 07:13 PM
Drac0 (Mark)
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can anyone advise on a good deep sky camera for a Meade 14'' sct
cheers JG
Depends how much you wish to spend, and you don't say if you will be using a reducer, which makes a big difference too. But really any of the CMOS deep sky cameras will work, except maybe the 183MM/MC. But the 533, 294, 1600 etc, etc will all work though you will need to use binning of up to 4x4 to alleviate oversampling, depending on camera/reducer combination.

Cheers,
Mark
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Old 02-07-2022, 10:26 PM
Dave882 (David)
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Thereís certainly a few things to consider such as osc vs mono, sensor size, QE etc - budget is probably a big factor. But as mention by others, at long fl 2 big considerations will be pixel size and fov.

In my experience with a c14 itís good to extend your fov as much as practical with a bigger sensor, otherwise thereís going to be very limited targets you can fit in. But be careful as some reducers will significantly reduce your image circle and provide substantial vignetting on larger sensors.

CMOS cameras will usually win on QE, but donít come with larger pixels but you can always bin. I donít necessarily see a problem with this- just bin according to the condition or your mounts guiding accuracy.
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Old 03-07-2022, 12:00 PM
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ccd

thanks everyone, all your advice much appreciated
cheers J G
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Old 03-07-2022, 02:15 PM
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muletopia (Chris)
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maybe

QHY8l 7.8 micron pixel size, A one shot colour

Chris
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Old 03-07-2022, 03:52 PM
johnnyjetski (John)
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John...You certainly need a large pixel size, and a Focal Reducer. I use an Atik Infinity OSC with its large 6.3 micron pixel. A 0.63 f/r still needs binning 2x2 on my Meade14 LX200GPS. A 0.33 f/r brings the huge focal length down to a more manageable level where binning is not necessary, and many other cameras can be sucessfully used.
Very versatile scope and camera but a focal reducer or reducers are needed.
John
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Old 03-07-2022, 05:46 PM
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You know, just for fun, its worth drilling down with a specific use case on this long FL OTA. I used SBIG ST8XME and ST10XME CCD cams many years ago on a meade 12" SCT, the ST8 used a KAF-1603ME sensor, it's over 15 years old. Specifically for narrowband imaging, Ha response is key to detail in LRGB processing. The ST8 had 75% QE at ha, 9 micron pixels and 100000 e well depth. No CMOS cam under $100k comes remotely close to these specs. Ok its only 1530 x 1020 pixels, but any bigger on a 14" f10 OTA is problematic anyway. If exposure times are long enough to overcome read noise, then read noise is irrelevant, and with accurate darks, dark noise is not a problem. If expense is a concern the ST8XME or ST10XME S/H would be cheaper and vastly superior to most CMOS cams for specifically narrow band imaging on this OTA, if you can find one!.

Last edited by Bassnut; 03-07-2022 at 06:06 PM.
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Old 04-07-2022, 10:37 PM
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The asi2600 CMOS is hitting 80% qe for Ha, and 50k full well, but yes tiny pixels. Iíve never seen a side by side comparison with the st8 (or eqivalent CCD), but Iím assuming if you limited your sub exposures and binned, you would still be in front. (Assuming cost and availability are ignored)

Fred- Iím interested to know why youíd recommend such small sensors for long-fl scts? Surely with a good reducer/corrector such as the offerings from Starizona it would be much preferable to go as large as possible? I was imaging
Ngc55 the other night with my c14 and I could only JUST fit it into the fov of my apsc size sensor (at f7 with Starizona SCR LF reducer). Fairly well corrected over entire field, but any sensor smaller for me would just be super frustrating.
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Old 05-07-2022, 08:41 AM
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With the Meade 12" f10 I had, I used it with and without a FR. Yes, I could fit more in and image faster with the FR, but I went through a phase where I got sick of the usual objects and went for small galaxies and especially small PN. Without the FR a large number of choices suddenly became doable at a reasonable res and my whole selection process changed, it was a breath of fresh air. The size of the sensor was not a problem as these were all small. Then I went back to the FR and all these objects became too blocky and not worth imaging. Then I was stuck in this zone of regular objects again without being able to do PNs properly.

A 14" f10 FL was popular decades ago but is in a relatively niche space now (everyone is going wide field) so my thinking was use its uniqueness for what other cant do, small galaxies and PNs, where sensor size is not so much of an issue (and CCDs have a much bigger well depth BTW, that can really matter).

I dont know, havent tried, does using a small pixel CMOS binned with a FR on cropped images of PN give a similar result as a large pixel sensor without the FR?. If so, then Im wrong about my thinking and of course a large sensor would be much more versatile.

The full FL at f10 imaging is more difficult of course, but the challenge and producing"different" images is very rewarding.

Last edited by Bassnut; 05-07-2022 at 08:58 AM.
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Old 05-07-2022, 10:38 AM
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With the Meade 12" f10 I had, I used it with and without a FR. Yes, I could fit more in and image faster with the FR, but I went through a phase where I got sick of the usual objects and went for small galaxies and especially small PN. Without the FR a large number of choices suddenly became doable at a reasonable res and my whole selection process changed, it was a breath of fresh air. The size of the sensor was not a problem as these were all small. Then I went back to the FR and all these objects became too blocky and not worth imaging. Then I was stuck in this zone of regular objects again without being able to do PNs properly.

A 14" f10 FL was popular decades ago but is in a relatively niche space now (everyone is going wide field) so my thinking was use its uniqueness for what other cant do, small galaxies and PNs, where sensor size is not so much of an issue (and CCDs have a much bigger well depth BTW, that can really matter).

I dont know, havent tried, does using a small pixel CMOS binned with a FR on cropped images of PN give a similar result as a large pixel sensor without the FR?. If so, then Im wrong about my thinking and of course a large sensor would be much more versatile.

The full FL at f10 imaging is more difficult of course, but the challenge and producing"different" images is very rewarding.
Ok I get you. Thanks.
Yes, while challenging at times, long fl imaging presents a heck of a lot of unique targets and in the relatively short time Iíve had my c14 Iíve really come to love it. In my setup, with the FR in place, Iím imaging at 0.28Ē with the reducer and 0.2Ē without (unbinned). But I need several minor miracles to occur to make use of that res so binning is done to some degree in post processing. But thereís really no chance of blockyness when your pixels are that small! Just need a crop.

Having said all that, I have not done a direct comparison - big pixels unbinned vs small pixels binnedÖ would be interesting to see if it makes a difference
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Old 05-07-2022, 01:08 PM
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can anyone advise on a good deep sky camera for a Meade 14'' sct
cheers JG
Hi John,

Along with the various astro-camera suggestions already provided and in light of your focal length, you could also try various typically 10 to 24 Megapixel full-frame DSLRs if needing pixels in the range of 6 to 9Ķm to keep your image scale in the zone and your field of view as wide as possible. It would be a fraction of the cost of a full-frame astro-camera and could be useful as an entry level full-frame test.

Best
JA
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Old 14-07-2022, 08:19 PM
gb44 (Glenn)
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Camera for C14

Bit late sorry but heres some food for thought.

Have you seen the C14 pics taken by Nial on AStrobin ? Hes done a few DSO pics lately so check em out. https://www.astrobin.com/k37d19/
Hi planetary pics show how the C14 reigns supreme for solar system stuff.

Consider QHY cameras - seen Peter Wards pics lately lately? If you want full frame with 120,000 FW depth and 24Mp look at the review of the 410c by Tony Hallas.
https://astronomy.com/magazine/produ...hout-the-noise

Modern DSLRs are good but uncooled ...

Cheers
GlennB
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