Tell me about your AM3 / AM5?

[Ags]

Can you do short (6s-20s) unguided subs with these mounts at a focal length of up to 400mm? 

In alt-az mode can you point at a target and engage tracking. I don't use goto but do like tracking.

What sort of scopes are reasonable for these mounts? I can never afford a large SCT so could either cope with 10" newtonian?

[Elp]

Not those mounts but I've done 9s at 370mm FL with my Z61 on an AZGTI in alt az. Wasn't the best result. Alt az isn't really ideal unless you're running around f2 or have a larger aperture, it also depends on what you're imaging. When doing eq with any other mount you can expose for longer, I've done 20s and within the space of an hour I don't think the target even moved from centre at 300mm FL and can likely go to around 60s depending on the focal length and optics.

Edited December 30, 2023 by Elp

[Ags]

I am happy using 6s subs with my AZ-GTI. This works fine for DSOs. My question was more about the unguided performance of the harmonic mounts, as they are really designed for guiding but I hope to not use guiding as it is not needed for my supershort subs. The only reason for me to use longer subs is to reduce storage requirements and processing time.

I would only use the AM3/5 in alt-az mode for visual and planetary imaging. Theoretically both these mounts could cope with a 10" newt, but they are so small I can hardly believe it.

[Elp]

My hem15 is even smaller and tosses around the C6 or Starfield 102 like it's nothing, the nerve wracking thing is whether the tripod will fall over but always wise to test the east and west heavy balance before trusting it to automatically do a meridian flip when imaging.

[Ags]

Interesting. I had discounted the HEM15 partly because it has no at-az mode, but also because I understand unguided imaging is impossible with the non-EC Ioptron harmonic mounts. Have you ever tested this by any chance?

[Elp]

Not yet. I'm going to be testing it with the SF and a few other bits of gear if this poor weather ever decides to shift.

As mentioned my gem28 when imaging E3 comet earlier this year within an hour the target didn't really move from centre, but as you say the gem isn't a HD mount whereas the hem has the drive on the RA.

[Ags]

You've got me thinking about the HEM15 again. It is more in my price range, and I like the weight. I'd really be interested in test exposures - say 5/10/20 seconds, if you have the time to try this out. In general how are you finding the mount?

At the price differential I can live without EQ mode. In terms of scope upgrades, it would let me mount a C8 at least. That would be a nice bump up from the C6 for lunar observations and planetary imaging.

I also see the mount can be trained with PEC...

[Elp]

I quite like it. It was intended as a replacement for the gem28. I was in a similar position, first I wanted the am5, then the am3 got announced but took ages to be supplied to resellers so I went for the hem15, mostly due to price (is the +500 justified for the am3 for added hd drive in declination, alt az mode etc? I didn't think so), the hem15 is also smaller, lighter and uses slightly less power (important as I usually use batteries, and mindful for if I take it off site) and it was important for either of the mounts for them to be compatible with 3/8 photo tripods (I've got strong sturdy ones) as well as being able to handle an 8 inch SCT for future possible upgrades. The biggest plus is I can pack it together with the C6 and all the AP gear into one backpack with tripod in hand.

Autoguiding probably isn't as good as the ZWOs, the lowest rms ive managed is 0.6, my gem28 I've had 0.4 but I didn't really have a bad sub over a 3-4 hour session so performance was adequate, and the declination wasn't even balanced during this session (only imaging 135mm though). The true test for it will be long focal length imaging which apparently HD mounts aren't suited to. The azimuth locking mechanism is awful however, I leave the locks loose as it knocks out the polar alignment if I tighten them, looking at it I don't know if I can add in washers to alleviate this issue. The fixed altitude range adjustment is also fiddly and a work table job, but once done the fine altitude adjustment knob is okay to use within the fixed set range.

I'll try and do some unguided tests, but judging by the weather systems it likely won't be for another 4-6 weeks.

[Ags]

To be honest, I have been all over the place looking for a mount that tracks reasonably in EQ mode and can take something a bit heavier than a C6. I started out thinking of an EQ5 with an RA motor, on the basis that this option has the least to go wrong. The issues with it are no AZ mode and weight. That got me thinking about harmonic mounts, but I think realistically they need guiding which I really don't want to do. I have no doubt I can figure out guiding but I want to keep things simple with less to set up and fewer points of failure.

Now I am thinking the new EQ-AL55I mount may be the best fit - it is over 2 kg lighter and smaller than the EQ5, and according to SkyWatcher can even take more load (10 vs 9 kg for the EQ5). It also partially supports ALT-AZ mode, unfortunately the firmware does not permit tracking in ALT-AZ, but you can still use it manually with motorized slow-mos.

Edited December 31, 2023 by Ags

[Elp]

I wouldn't worry too much about troubles with setting up autoguiding, in fact it was this and my asiair addition which transformed my imaging. In all seriousness it was focusing the 30mm guidescope initially which provided the most trouble (as at the time I used to setup and breakdown the 224mc camera within it, now I leave it assembled). The software side pretty much worked without issue. Setting up autoguiding will open your available mount options rather than hinder.

[Ags]

Ok, so I have these items in the shopping cart:

- HEM15 (with or without ipolar?)

- ASIAIR Mini

- ASI120MM Mini

I have a just fine guidescope in my FMA135. Maybe my 50 mm RACI finder could also be pressed into service...

Does the HEM15 come with a handset and counterweight rod?

[adyj1]

9 hours ago, Ags said:

Does the HEM15 come with a handset and counterweight rod?

Yes, it comes with a 'proper' handset (star database and all the gubbins), but no counterweight bar. The payload is 8kg without a counterweight, and 12kg with (it takes the same counterweight bar as the Skyguider Pro). 

[Ags]

OK, thanks. Do you know if the mount base is compatible with 3/8" photo thread - this is used by all my tripods.

I don't need to worry about the counterweight for now as my heaviest scope is a C6. I could go up to a C8. Not sure I could go bigger - a C9.25 is easily in the weight capacity of 12 kgs, but that 12 kg is quoted for a tube diameter of 220mm. Upgrading from the C6 to a larget SCT would be for visual and planetary AP only.

Does anyone know if I need the iPolar version if I get the ASIAIR? I presume it can take care of polar alignment with the main camera?

Also wondering how many people use ASIAIR visually. I don't like goto but I might like it more if I add plate solving for better precision.

Edited January 2 by Ags

[Elp]

You don't need ipolar if you're using the air to PA, the air is infinitely more useful as you don't need a laptop and can use your phone to interface with it.

I often use goto and the air for visual making the guidescope the "main" camera to do the plate solving. Due to high bortle 7 it saves so much time rather than manually searching. You may need to slightly slew the scope due to the slight fov difference between the guidescope and main scope, unless if you use a flip mirror diagonal.

[Elp]

The counterweight bar thread looks to be a photographic 3/8 16tpi, I've just tested it with a bolt, but it's a through hole so if you decide to DIY the bar with an all thread it'll need a physical stop (like a nut) to stop the bar from screwing in further. This hole is the same as the mount head hole, so yes compatible with photo tripods as I believe the AM3 and 5 are too, I use my hem15 with 3/8 tripods.

[adyj1]

3 hours ago, Elp said:

I use my hem15 with 3/8 tripods.

I have the HEM27, and the centre hole on that is not threaded and just used for a locator pin - it's the bolts on the east/west sides of the mount that clamp it to the base. From the FLO pictures the HEM15 looks similar, but if you can screw it to a photo tripod in that would be handy. 

Mind you, without a counterweight, I imagine the centre of balance could move quite a bit away from centre, so I would assume you would have to make sure you use a pretty stable tripod...

[Elp]

Hem15 definitely has a 3/8 centre mount hole, one of the reasons I bought it. I have two sturdy tripods, and it's always wise to check the max east and west heavy balance to make sure it doesn't feel like toppling over before using it, especially before allowing an automatic meridian flip to happen when imaging.

[Ags]

I might be moving to an upstairs apartment, so I think the HEM15 might be the only game in town. The move isn't a disaster though, it's part of a plan to buy a pad in Greece or Spain. So an airline-friendly HEM15 would be a winner there too.

What's a good battery to power an ASIAIR Mini?

[Elp]

You can use any usb power bank really. During solar observing I use a 20000mAh one which is probably overkill as it'll last hours and hours on that one via a usb A to usb C cable. For my AP sessions the better one I use is my Talentcell 72W'

https://www.amazon.co.uk/TalentCell-Rechargeable-11000mAh-20000mAh-Portable/dp/B06Y5G3C8Z/ref=mp_s_a_1_2?keywords=talentcell&qid=1704222644&sr=8-2

Runs for around 2-3 hours, you'll need a 12v adaptor cable as the input pin type for the hem15 is different from the asiair 12v cables if you use the air to power everything, or you can power the hem15 separately from the air.

If you want the air to control the hem15 the included usb cable with the hem has to be plugged into the hand controller and the other end of the usb cable into the air. Hem15 I don't think is in the air mount list but selecting the hem27 as your mount does the job.

 

Edited January 2 by Elp

[Ags]

I have one of these, although I have lost the charger!

TalentCell Rechargeable 36W 12V 6000mAh 5V 12000mAh

I was thinking of buying another to have two packs and one charger.

@Elp why is your imaging so power hungry - are you running a cooled camera or dew strips? Or does the power usage of the AIR or mount spike when imaging/guiding?

Edited January 2 by Ags

[Elp]

Anything running via 12v is power hungry. Yes it's a cooled camera. If I use an uncooled camera it runs slightly longer. If I'm using my C6 this is also connected to the 12v for the dew heater ring. Cold temperature also doesn't help with batteries. For my refractors the dew heater bands are powered separately because they use a lot of power.

The portability vs run time works for me. If I go off site I doubt I'd be imaging longer than 4 odd hours anyway, or I'd run two rigs for two hours each. The batteries I have need to be stored all with the equipment together in one carriable package, larger batteries won't fit this requirement.

[adyj1]

54 minutes ago, Ags said:

I was thinking of buying another to have two packs and one charger.

Don't let me stop you buying another one, but there's nothing special about a talentcell charger - 12v/3A DC 5.5/2.1mm barrel plug... (switch the battery on to charge) 

Ady

[Ags]

2 hours ago, adyj1 said:

Don't let me stop you buying another one, but there's nothing special about a talentcell charger - 12v/3A DC 5.5/2.1mm barrel plug... (switch the battery on to charge) 

Ady

Thanks for the charger specs - you've saved me a bit of cash.

But to be safe I'll closely supervise the next few chargings.

Edited January 2 by Ags

[Ags]

3 hours ago, Elp said:

Anything running via 12v is power hungry. Yes it's a cooled camera. If I use an uncooled camera it runs slightly longer.

Surprised using an uncooled camera doesn't make more of a difference! My only experience is running my AZ-GTI and that hardly dents the power levels each night.

[Elp]

10 hours ago, Ags said:

Surprised using an uncooled camera doesn't make more of a difference! My only experience is running my AZ-GTI and that hardly dents the power levels each night.

Using the azgti, mini and an uncooled cam generally doesn't. When it's fully autoguided loaded and constantly taking images with a cooled camera (level of cooling makes a difference, I normally cool to minus 10 deg C) the same battery probably stretches to just over 3 hours. During warmer nights it's ever so slightly longer. If I'm just using the azgti only the power pack lasts over 5-6 odd hours and my Celestron Lithium LT then becomes usable for it.