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Planetary camera


Ken82

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47 minutes ago, vlaiv said:

I was under impression that following happens:

12 bit mode is recorded in 16bit mode by padding LSBs with zeros (4 LSB)

10 bit mode is recorded in 8bit mode by discarding 2LSBs

Your impressions are right if recorded means output from the camera. 🙂

The camera will record in 12 bit (normal mode) or 10 bit, (high speed mode). If you select 8 bit o/p it will discard the necessary number of LSBs and if you select 16 bit o/p it will append the necessary number of zero value LSBs.

Alan

Edited by symmetal
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17 minutes ago, symmetal said:

Your impressions are right if recorded means output from the camera. 🙂

The camera will record in 12 bit (normal mode) or 10 bit, (high speed mode). If you select 8 bit o/p it will discard the necessary number of LSBs and if you select 16 bit o/p it will append the necessary number of zero value LSBs.

Alan

I think I was mistaken in thinking that 10 bits of high speed mode were lower 10 bits of 12bit ADC, while in fact they are higher 10 bits.

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Jumping on the bandwagon here. I'm looking for an imaging setup for lunar/planetary based around a C9.25. With the planets low at the moment I know it's not going to be great in terms of seeing and I'll probably be more focused on lunar. Thinking to get something like a ASI 120MC/MM to get started and later re-purpose it and then upgrade to a 178 or 290 (or similar). Or should I just go for one of the latter? I have a leaning towards mono but how would the colour/mono versions of 178/290 work with this setup? Barlow? In terms of the math (pixel size, focal length, etc.) are the aforementioned OK with the C9.25 (I'm usually in Bortle 5/6)? I also have a 60mm F5.9 which I intend to use on a portable setup so anything that works with that (not essential as I have a DSLR) would be good.

Are ZWO the only game in town?

One other thing, my old clunker of an astro lapop is USB 2.0. Is that going to be a major bottleneck or just slow things down?

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9 minutes ago, inapottingshed said:

Jumping on the bandwagon here. I'm looking for an imaging setup for lunar/planetary based around a C9.25. With the planets low at the moment I know it's not going to be great in terms of seeing and I'll probably be more focused on lunar. Thinking to get something like a ASI 120MC/MM to get started and later re-purpose it and then upgrade to a 178 or 290 (or similar). Or should I just go for one of the latter? I have a leaning towards mono but how would the colour/mono versions of 178/290 work with this setup? Barlow? In terms of the math (pixel size, focal length, etc.) are the aforementioned OK with the C9.25 (I'm usually in Bortle 5/6)? I also have a 60mm F5.9 which I intend to use on a portable setup so anything that works with that (not essential as I have a DSLR) would be good.

Are ZWO the only game in town?

One other thing, my old clunker of an astro lapop is USB 2.0. Is that going to be a major bottleneck or just slow things down?

If you want to focus on lunar - sensor size plays a part - the bigger the better as you'll need to take less panels for lunar mosaics.

178 wins here.

For lunar I would also consider mono over OSC as there isn't much color on the Moon. Mono will also let you do some fancy stuff better like UV photography of clouds on Venus and CH4 methane band and use of NB filters to tame the seeing.

Again,

178 has 2.4um pixel size, optimum sampling rate is F/9.4 for mono and double that for color (F/18.8)

290 has 2.9um pixel size, optimum sampling rate is F/11.4 for mono and double that for color (F/22.8)

120 has 3.75um pixel size, optimum sampling rate is F/14.7 for mono and double that for color (F/29.4)

I'd say you would need barlow for any color camera and ASI120 in mono. 178 and 290 in mono don't need barlow as they are close to native F/10 of the scope.

ZWO is not the only game in town, QHY, Altair Astro also make cameras with same sensors.

If you can, get USB3.0 laptop and camera as speed of USB 3.0 enables much higher frame rates to be achieved - means more subs captured, means better stack / better SNR.

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1 hour ago, vlaiv said:

If you want to focus on lunar - sensor size plays a part - the bigger the better as you'll need to take less panels for lunar mosaics.

178 wins here.

For lunar I would also consider mono over OSC as there isn't much color on the Moon. Mono will also let you do some fancy stuff better like UV photography of clouds on Venus and CH4 methane band and use of NB filters to tame the seeing.

Again,

178 has 2.4um pixel size, optimum sampling rate is F/9.4 for mono and double that for color (F/18.8)

290 has 2.9um pixel size, optimum sampling rate is F/11.4 for mono and double that for color (F/22.8)

120 has 3.75um pixel size, optimum sampling rate is F/14.7 for mono and double that for color (F/29.4)

I'd say you would need barlow for any color camera and ASI120 in mono. 178 and 290 in mono don't need barlow as they are close to native F/10 of the scope.

ZWO is not the only game in town, QHY, Altair Astro also make cameras with same sensors.

If you can, get USB3.0 laptop and camera as speed of USB 3.0 enables much higher frame rates to be achieved - means more subs captured, means better stack / better SNR.

The 178 is sounding good. What would be a good brand/product EFW and filter set to use with it?

Apologies to the OP for bending the thread slightly.

Edited by inapottingshed
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1 minute ago, inapottingshed said:

The 178 is sounding good. What would be a good brand/product EFW and filter set to use with it?

Apologies to the OP for bending the thread slightly.

I use baader RGB filters for DSO imaging, but I think for planetary I would go with cheapest filter set as you don't need to worry about faint reflections / halos and such.

As for filter wheel - I don't have one, I use filter drawer, but I did get my eye on one of these since I'll be making permanent setup / obsy next year:

https://www.firstlightoptics.com/filter-wheels/zwo-mini-electronic-filter-wheel-efw-5-x-125-or-5-x-31mm.html

It's not that expensive and has positive reviews. I did not do much research but you want your EFW to be repeatable - filters always in the same position (so you can reuse flats) and there is no light leak.

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6 minutes ago, vlaiv said:

I use baader RGB filters for DSO imaging, but I think for planetary I would go with cheapest filter set as you don't need to worry about faint reflections / halos and such.

As for filter wheel - I don't have one, I use filter drawer, but I did get my eye on one of these since I'll be making permanent setup / obsy next year:

https://www.firstlightoptics.com/filter-wheels/zwo-mini-electronic-filter-wheel-efw-5-x-125-or-5-x-31mm.html

It's not that expensive and has positive reviews. I did not do much research but you want your EFW to be repeatable - filters always in the same position (so you can reuse flats) and there is no light leak.

Thanks. I'm in a similar situation in that I'm planning a ROR next year and trying to preserve funds for what is likely to be a big hole. I worry that if I use a drawer I might end up dropping filters in the dark/mud!

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2 minutes ago, inapottingshed said:

Thanks. I'm in a similar situation in that I'm planning a ROR next year and trying to preserve funds for what is likely to be a big hole. I worry that if I use a drawer I might end up dropping filters in the dark/mud!

Drawer is really not practical for planetary as one needs to change filters rapidly as not to loose any imaging time (planets rotate and one does not have very long window for imaging). This is why I linked to EFW. Maybe even regular manual filter wheel could be used, but I would not use drawers for planetary.

DSO imaging is different - you don't loose much of imaging time if you spend one minute on filter change there.

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2 minutes ago, inapottingshed said:

Thanks. I'm in a similar situation in that I'm planning a ROR next year and trying to preserve funds for what is likely to be a big hole. I worry that if I use a drawer I might end up dropping filters in the dark/mud!

I used to use drawers but it was a faff in the dark. Got a ZWO EFW mini which is a godsend! I used the Baader 1.25" RGB CCD filters and have found them to be parfocal - not having to refocus between filters is another godsend

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2 minutes ago, inapottingshed said:

Does the EFW have a button to operate by hand or is it computer control only?

Has to be operated by the computer.  Firecapture controls it via ascom for me

Edited by CraigT82
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1 hour ago, inapottingshed said:

Would there be any merit with in cooled 178? I think deep space targets might be limited due to the OTA?

Not if you use that 60mm F/5.9 or get decent Samyang lens.

I've got ASi178mcc - color cooled version and can't wait to test out newly acquired 85mm F/1.4 :D with it.

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