Martthebass

It was nice to get a clear night last night, the first decent seeing in many weeks. The AM5 took advantage of the good guiding and gave me 0.40” rms over the 4 hours with the little Redcat51 on board.

Nice shot. I usually struggle with this target. I got about 90 minutes the other night before the clouds rolled in. I never seem to be able to get the colours right in SiriL, on the AAP stack it’s ok (red and green with the L-enhance) but I get yellow and white on post processing.

40 minutes ago, alacant said:

Hi everyone

Not seen many of these so far this season so...

Thanks for looking and do remind me how this should be done!

nt150s + UHC ~5h calib-apilado siril 3.0.0a proc. st 1.9.558b

I had a go at this with my new (to me) Redcat the other night. Couldn’t get the colours right though….more work required.

18 minutes ago, Elp said:

Looks snazzy when it all matches.

Some of the ZWO red bits are starting to go pink 😂

Well a Redcat 51 v1.5 came up for sale at a very reasonable price locally so I took the plunge. The sky is looking ominous at the moment but ‘Clear Outside’ assures me it will be clear by 9pm for a good few hours. So, I’ve swapped out my SM90EDT and put on the Redcat for a hopeful first light.

With only a couple of hours of reasonably clear skies in these parts over the last 6 weeks it’s not been the best time for imaging. So with these 2 hours I decided to do something foolish and aim at Abell 39. I think this is one of the most beautiful PNs in the sky with its almost perfect spherical symmetry. The image certainly isn’t great, I needed at least 3x the integration time to get the noise down but im just happy I could see it at all.

I’ve been hunting about for a decent comparison between these 2 but so far not seen anything that helps much. I’m looking for a little mobile wide field set up; I’ll be using it on my AM5 with an ASI533MCP. I’d pretty much settled on a Redcat51 but the Askar looks interesting.

I’ve just been reading a post on the FB AM5 users group regarding a user who’s noting that the tracking/guiding performance on his unit has deteriorated significantly with time but stating that his has had significant use - probably much more than any UK users. I was an early adopter and have had mine just under a year, I estimate in that time the mount has probably had about 50 outings. So far the mount has been pretty consistent with typical performance in the 0.6” range but worse if the seeing is dodgy but rarely averaging above 1”.

Is anyone seeing any deterioration in their unit that could cast doubt on the durability of ZWOs execution of this technology?

On 13/06/2023 at 18:19, Gary Clayton said:

I see that the1:1 field flattener is now available from FLO, I will let you know how I get on with it once it arrives

 https://www.firstlightoptics.com/stellamira-telescopes/stellalyra_adj_flat_90_125.html

Thanks Gary, interested in this as I'm looking at getting something more widefield than my EDT90 and going to a longer FL on the 90 would give me a better separation.

Sorry, typo, meant AAP

3 hours ago, Adam J said:

You would get as much additional FOV by selling the 533 and buying a rising cam 2600 equivalent and have more change left over than buying a redcat. 

 

Adam

Good idea but I’d be completely lost without my AAP 😂

I’m currently using a 90mm triplet apo with a 533MC and would like to look at doing some more wide field views than that offered by the 432mm reduced focal length offered by my existing setup so I’m considering looking at adding a Redcat 51 to facilitate this. I’m not exactly flush with cash and so will have to persevere with the 533 at least for a while which I’m aware isn’t technically a good match. Does anyone have a good experience (or bad) with this arrangement?

Just making a quick image now. Some high level haze but the SN looks very bright now, so bright I thought it was a foreground star at first.

14 hours ago, Northernlight said:

Elp, i just saw a nice one that is just within the weight limit. FLO does the StellaMria 90mm carbon fibre triplet which comes in at 4.5k with all the rings and dovetail etc, then my 30mm guider and asi 585 camera weight 413g, so i'll be coming in just under the weight capacity limit at 4.9kg but then add 100-300g for a flattener.  I figure if i take off the handle i can get it bang on 5kg. 

With a small camera sensor i might not need to even use a Flattener.

 

I'm using the 90EDF, albeit on a bigger mount and it's a cracking little scope.  I do use the flattener on a asi 533 but I concur you would probably get away with it on the 585

14 hours ago, vlaiv said:

Do people find value in these mounts and if so, what is it? Portability? Lack of backlash?

Spec wise, I don't see them being high performing mounts. P2P periodic error of >25". Period of periodic error of 288 seconds - faster than other mounts which puts strain on guiding (faster change in periodic error).

0.17" / micro step tracking resolution being in the same ball park as for example Heq5 or EQ6 (in fact these have ~0.14" / micro step).

Reduction of 300:1 requires steppers to operate on 128 micro steps. Period is actually one full revolution of stepper motor

200 steps * 128 micro steps = 25600 micro steps per revolution of stepper motor

Sidereal rate is 15.041"/s and if stepper resolution is 0.17"/ micro step that makes ~88.5 micro steps per second (sidereal / resolution). 25600 micro steps per one motor turn / 88.5 micro steps per second = ~289 seconds per motor turn.

I wonder if PE comes directly from step motor?

In any case, I see these mounts as being overly expensive for what they offer - unless I'm missing something that people value.

 

I think individuals value different things. Having experienced ill health of late I was looking at something lighter and quicker to set up than my previous AZEQ5 Mount with 90mm APO set up.

The AM5 set up is now an easy one lift solution. I also don’t need to be concerned about balance. The PA adjustment is easier and quicker also; generally I can be up and running in less than 10 minutes which means I use the set up more as I can take advantage of short or unexpected periods of clear sky. I’ve always considered the best set up is the one you use the most.

Regarding guiding, it’s better than my AZEQ5 was with me typically getting 0.6”rms and on good seeing nights (like last night) around 0.3”. I’d maybe get better on an EQ6 type but lugging it around would mean it would gather dust.

I don’t disagree that it’s not a cheap option but for some, like me, it’s been a game changer.

A bit surprised by this, I thought they'd go for a higher capacity job first.  

As the weight isn't that much lower than the AM5 (but the mount capacity is) I think the final RRP in the UK will need to be a good bit less than the AM5 otherwise the AM5 would make more sense from a flexibility point of view.  I'm more than likely going to be proved wrong though...

Just cooling and awaiting sufficient stars to enable PA.  My lightweight 'one-lift' job.

I love Orion and it’s environs, sadly my house and trees are in the way most of the time and I only get a short window of opportunity. I managed about 30 minutes last night but not too keen on the result with the L-Enhance...

Also, managed to blow the core as I used 60s subs - looks far less blown out on the original image though.

Thanks for the write up, very informative.  I came from an AZEQ5 to the AM5; I always struggled to get good balance on set up (same 90mm scope as yourself) and it meant that I spent more time out in the cold than I liked.  I wanted a one lift out and due to a current health problem I also went the TEC40/PE160 route so I could do this without undue grunting.

I've generally found my RMS error to be about 0.6" with the odd excursion to 0.8" which is more than adequate on 300s subs at my focal length.  Sometimes, when seeing is better than average this comes down to 0.4" or a bit lower (all on 1sec guide exposures).  I've not done much research into the effects of good PA, I generally make sure it is <1' (normally <30") and check after I've locked off the mount and generally always get the figures above.  I've not had the setup out in 'big wind' but it wouldn't surprise me if the mount was a bit susceptible to the odd gust.  

Regarding calibration; I used to do this every time with the AZEQ5, with the AM5 I've generally found I only 'need' to do it every 4 or 5 sessions, not sure why that is the case but it does seem to be fairly consistent from session to session.

Overall, like you I think it's been a positive experience so far, the only negative experience so far was when the mount inverted the scope into the tripod when sent to home at the end of a session....never found the reason for that and concluded it was an ASIAir glitch (it did manage to do this with my AZEQ5 once) - fortunately it hasn't happened since. 

@JCIdaho Yes I'm using the ASIAir+.  I've not had a problem with 'stopping' near the Zenith, but if you are in live mode on the AAP it does stop when it hits the meridian as it wont perform the auto flip in that mode.

On 14/11/2022 at 11:03, JCIdaho said:

Using a StellaMira90, but with a chunky imaging train on the back.

I can't see any damage, and it subsequently worked OK. I've ordered the pier extension, I hope all will be well.

I'm using the Stellamira 90 on my AM5 and can confirm that shooting near the Zenith hasn't been a problem with the 160mm pier extension.

I use the ZWO 30mm F4 and ASI120mm set up and it works just fine.  A bit of a faff getting focus first time (did it in daylight on a distant tree and jiggled the cam in-out of the tube and then locked it off) but once set it's never needed adjusting.  Guides my 90mm reduced FL (432mm) set up ok at 1s guide exposures.  Hope you get sorted.

I had read something recently on the Facebook group for this camera that the latest model needs 12v power to operate. The older version (like I have) only needed 12v power to operate the cooling, the camera would still operate uncooled without power.

Power connection can be a bit fiddly, on occasion mine has not been quite located when pushed home and I only noticed when the camera failed to cool. I now power it with a short cable from the ASIAIR plus for this reason.

I look forward to it Mandy. I only managed one image of it last year, my south and west aspect is pretty obscured and I can only get about 30 minutes before the trees get in the way. With the new mount I’m a bit more mobile so hoping for better things this year.

10 hours ago, Mandy D said:

Sadly, not had a chance to use it yet. I'd love to have a proper session on M42 with it, but still having problems with my eye, so it might be a while yet. How are you doing with the new mouunt?

Sorry to hear that Mandy, it should do well on M42 with the RC6.  Did you pick up an ASIair to run it with?

The new mount has been a bit of a learning curve (especially the guiding aspect) but it's been worth it, it's a one lift out for the rig and I can now be up running, guiding and imaging in less than 10 minutes which is useful with our skies.