Planetary: TEC Vs Mono

[Mav359]

Hi Guys

Is cooling as important in a CCD/CMOS when planetary imaging?

I'm looking for a camera for planetary imaging, i have a QHY8L for DSO's so whatever camera i go with it won't be used for that.  Soooooo

1) Would i be wasting money buyinig a TEC cooled CCD bearing in mind i'm not imaging for great lenghts of time?

2) Would you rather have say a QHY5-II Mono & filters rather then TEC cooled CCD

Cheers

[michael.h.f.wilkinson]

In the short exposures of planetary imaging, thermal electrons do not have time to build up, really. Read-out noise completely swamps thermal noise as a rule. At the moment the leading contenders in the planetary world are the ASI120 (MM/MC) and the DMK/DFK21 with the ICX618 chip. These are non cooled and provide great shots

[Mav359]

Cheers Michael

I see from your signature that you have both, any preference?

[michael.h.f.wilkinson]

I like the ease of use of the ASI120 MC colour camera. The DMK21 is mono, so a bit more involved in its use, but has the edge in that you can do IR RGB or LRGB images which can have the edge in sharpness. I like o have both options. I ended up with an ASI and a DMK largely due to offers on ABS-UK and its Dutch equivalent.

[Zakalwe]

2) Would you rather have say a QHY5-II Mono & filters rather then TEC cooled CCD

Cheers

As Michael has said, cooling on a planetary camera isn't that important. The very best planetary imagers don't use cooled cameras. From the little that I know, adding cooling to a planetary cam is an attempt to make a dual-purpose DSO/planetary camera (like the IMG0H and the Atik Titan).

Me personally, I'd rather have the mono and filters. Mono is a little bit more work (3 sets of data to stack instead of a single set), but the results are in a different ballgame. Plus the post-processing can be easier as the data quality is so much better it takes less work to get a decent image.

here's a quick'n'dirty comparison that I did for my local astro society. I used a colour DFK21au618 camera vs a mono DMK21au618. Both cameras use the same Sony sensor and both sets of images were taken with a Celestron C11 and Powermate 2.5.  The images were captured a few months apart, but the difference in detail is clear.

Mono vs OSC.pdf

I started out using colour cameras and to be honest, learning the basics of planetary imaging is hard enough without throwing in stacking and combining RGB data sets. Just getting the planet onto the sensor can be tricky enough, so I'd always recommend starting with an OSC. But I do wish that I converted to mono much earlier as the difference is so marked.

[oldpink]

was torn between the ASI 120 MC and the MM
I eventually went for the MC due to the ease of use and no filters needed though I do appreciate the loss in quality
eventually when I move over to CCD I will go Mono then get a filter wheel and possibly a MM and the MC will become a guide cam

In saying that I am more than happy with the MC, does what it says on the tin and then some

[michael.h.f.wilkinson]

As Michael has said, cooling on a planetary camera isn't that important. The very best planetary imagers don't use cooled cameras. From the little that I know, adding cooling to a planetary cam is an attempt to make a dual-purpose DSO/planetary camera (like the IMG0H and the Atik Titan).

Me personally, I'd rather have the mono and filters. Mono is a little bit more work (3 sets of data to stack instead of a single set), but the results are in a different ballgame. Plus the post-processing can be easier as the data quality is so much better it takes less work to get a decent image.

here's a quick'n'dirty comparison that I did for my local astro society. I used a colour DFK21au618 camera vs a mono DMK21au618. Both cameras use the same Sony sensor and both sets of images were taken with a Celestron C11 and Powermate 2.5.  The images were captured a few months apart, but the difference in detail is clear.

Mono vs OSC.pdf

I started out using colour cameras and to be honest, learning the basics of planetary imaging is hard enough without throwing in stacking and combining RGB data sets. Just getting the planet onto the sensor can be tricky enough, so I'd always recommend starting with an OSC. But I do wish that I converted to mono much earlier as the difference is so marked.

Very nice comparison. The main reason I have used the ASI120MC is the dreadful weather we have been having. I did not want to have L, R, but no G and B. Under better conditions I would certainly go for the DMK

[oldpink]

Very nice comparison. The main reason I have used the ASI120MC is the dreadful weather we have been having. I did not want to have L, R, but no G and B. Under better conditions I would certainly go for the DMK

same here In Scoland you take any time you get and having to do 4x the amount of runs (LRGB) isn't always possible

esp if you only get a short gap in the clouds to gather data, so it was one of the major influences on my decision to go with the OSC

[Zakalwe]

I used to do 2-3 minute runs on Jupe with the OSC. Now I do 3x50 second data runs. The collection time is exactly the same.

[oldpink]

I used to do 2-3 minute runs on Jupe with the OSC. Now I do 3x50 second data runs. The collection time is exactly the same.

yes I have heard and read a few posts regarding the time used by OSC and Mono + filters

Olly was quite convincing on the argument in a thread, thats why I may get the MM as a future upgrade

but my original idea was to keep setup time to a minimum and build up my knowledge rather than get in too deep and get Pee'd off because I didn't know enough to get it to work

to me the MC is like a point & shoot, no messing with filters and having to remember to change capture settings for each run as I'm very forgetful

[michael.h.f.wilkinson]

I used to do 2-3 minute runs on Jupe with the OSC. Now I do 3x50 second data runs. The collection time is exactly the same.

If everything is automated, fine, but if you have a manual wheel, and you are still finding optimal settings per filter, you take quite a bit more time. With Jupiter you also have the rotation to contend with (still need to install winjupos). My best ressult on Jupiter has been with the ASI130MM using IR RGB, but I have yet to get the DMK21 sorted out. The use of FireCapture has made things easier as it stores profiles per filter and per object.

[Zakalwe]

yes I have heard and read a few posts regarding the time used by OSC and Mono + filters

Olly was quite convincing on the argument in a thread, thats why I may get the MM as a future upgrade

but my original idea was to keep setup time to a minimum and build up my knowledge rather than get in too deep and get Pee'd off because I didn't know enough to get it to work

to me the MC is like a point & shoot, no messing with filters and having to remember to change capture settings for each run as I'm very forgetful

Olly was referring to long-exposure DSO imaging, which is a completely different kettle of fish. The two aren't really comparable.

If you are a beginner to planetary imaging then I'd agree. Go OSC as there's a whole lot to learn. The "mechanics" of planetary can be frustrating at first, especially if you are setting up and tearing down each night. I know that when I started it often took me ages just to get the planet onto the sensor.

If everything is automated, fine, but if you have a manual wheel, and you are still finding optimal settings per filter, you take quite a bit more time. With Jupiter you also have the rotation to contend with (still need to install winjupos). My best ressult on Jupiter has been with the ASI130MM using IR RGB, but I have yet to get the DMK21 sorted out. The use of FireCapture has made things easier as it stores profiles per filter and per object.

Yeah, Firecapture is a tremendous program, which makes taking RGB almost a one-button affair. We are so lucky that there are dedicated people out there creating and distributing programs like Autostakkert, Registax, EQMOD, Firecapture.

I personally don't use WinJupos. It's anything but user-friendly or intuitive. At some point I will have to learn it, I suppose, but until then I'll keep the imaging runs short enough to ignore rotation.

[Mav359]

cheers guys for all the advice...

i think im leaning towards the DMK whether that OSC or not i still have to decide. Filters and wheels drive the price up and knowing what i'm like i already like  the idea of a auto filter wheel.

Bonus time so hopefully (depending if i get one) i'll be buying something end of the month

Here we go again.

[Zakalwe]

The DMK is a bit long in the tooth now, and it's expensive for such a small sensor. I use mine for planetary imaging, where it still packs a heck of a punch, but I wouldn't buy one if I was starting out. I also use a Chameleon for Lunar and Solar and the results have always impressed me no end.

The ZWO cameras seem to be delivering great results on planetary, though I have seen plenty of reports of Newton Ring interference on bright objects (Solar and Lunar). it seems to be a bit hit-and miss though.