QHY268M & QHY268C Users Thread (Please share your knowledge and tips)

[tomato]

Thanks Vlaiv, I hadn't thought of this. In my working life I was used to glass viewing windows being made out of 2" thick borosilicate glass (on chemical reaction vessels) and hence not prone to much flexture (hopefully).

[Richard_]

17 minutes ago, tomato said:

I have just noticed this morning that along with the ambient air pressure, the sensor pressure reading has risen also. I'm aware this will go up and down in a sealed system in line with temperature changes, but it does appear to be tracking the outside air pressure, more evidence that the chamber is not sealed.

I know @Tomatobro has a barometer/RH station in his dome, he can maybe make a more precise observation on this when he sees then post.

Does your chamber plug still have the rubber/silicone o-ring attached? You'd like to think that would create a decent seal, if you have a leak that is. 

[tomato]

1 hour ago, Richard_ said:

Does your chamber plug still have the rubber/silicone o-ring attached? You'd like to think that would create a decent seal, if you have a leak that is. 

Yes, the threaded plug has the silicone o ring in place. I’m assuming there are some bonded joints on the sensor housing and there may be a wiring port somewhere? Certainly some potential sources of a leak.

[Stuart1971]

Well, I have had the desiccant tube in for 4 days now, and it’s running at 48% humidity  ambient and 60% at -10, so we will see how long that lasts, and no more dewing up ATM, Although I am cooling the sensor now over a 10 min period instead of 5 min as I was before.

[tomato]

Yes, since seeing the mist patch on the sensor I have extended the cool down to -10 deg C duration to 15 minutes.

There might be a good test of it tonight, as I wait for it to get dark there isn’t a cloud in the sky!🤞

[Stuart1971]

1 hour ago, tomato said:

Yes, since seeing the mist patch on the sensor I have extended the cool down to -10 deg C duration to 15 minutes.

There might be a good test of it tonight, as I wait for it to get dark there isn’t a cloud in the sky!🤞

Did you speak too soon, ?? as was the same here, and now just poured down….☹️

[tomato]

Yeah, recent early evening clear skies have not lasted into Astro darkness. Last night  I set up on a target for 9 hrs of imaging before the meridian flip, I got 90 minutes.

[Richard_]

It was clear all last night for the first time in 4 weeks and I imaged all night. LRGB on M33 until it set on horizon at around midnight and I then moved on to the Rosette nebula. I couldn't quite fit the rosete into my FOV, so I decided to go for a 2x1 mosaic with just H-alpha for fun as I haven't tried a mosaic with this camera yet.

It looks like I had some high cloud, the bright stars in my ~3hrs of LRGB on M33 show fuzzy halos which I've seen before on hazy nights. I'm a bit disappointed as I've wanted to do M33 for the past two years (I've either had cloud/rain, a full moon or a combination of the two).

On the other hand, the H-alpha data on the rosette nebula really surprised me! Even with just over 1hr per panel and the not so great seeing, the detail is incredible, you just want to zoom in more. I have to add that the PhotometricMosaic script by John Murphy worked brilliantly, no visible artifacts can be seen at the seams. This is a semi-processed image, it has been treated with all the Xterminator tools and such. I'm so glad I persevered and decided to add this target on after M33 had set. I'm looking forward to gathering some S and O data on the Rosette now

[tomato]

I might have a temperature control issue with my QHY 268c, I set it to cool to -10 degrees C as usual it got about half way there then the cooler power went to 100% which I didn’t notice straight away, when I did it was at -25. I set it to warm up but the temp is stuck at -18 to -20 deg C with 0% cooler power. Powering it down and on again had no effect, I didn’t want to waste the clear sky so I imaged with it, no problem with the subs.

It clouded out at 20:30, the temp indication is not moving, so I’ve powered it down and will look at it tomorrow.

[Stuart1971]

24 minutes ago, tomato said:

I might have a temperature control issue with my QHY 268c, I set it to cool to -10 degrees C as usual it got about half way there then the cooler power went to 100% which I didn’t notice straight away, when I did it was at -25. I set it to warm up but the temp is stuck at -18 to -20 deg C with 0% cooler power. Powering it down and on again had no effect, I didn’t want to waste the clear sky so I imaged with it, no problem with the subs.

It clouded out at 20:30, the temp indication is not moving, so I’ve powered it down and will look at it tomorrow.

Oh dear, I hope it’s not a serious issue…I noticed with mine that the longer I set the time to cool, the longer it takes to actually start cooling at all….i set it on 10 mins to get to -10, and the sensor temp was 0, it took 3 mins before the cooler even came on, which I thought was odd…

I have managed to get the humidity on mine down to 47% at -10, am out imaging tonight 

[tomato]

37 minutes ago, Stuart1971 said:

Oh dear, I hope it’s not a serious issue…I noticed with mine that the longer I set the time to cool, the longer it takes to actually start cooling at all….i set it on 10 mins to get to -10, and the sensor temp was 0, it took 3 mins before the cooler even came on, which I thought was odd…

I have managed to get the humidity on mine down to 47% at -10, am out imaging tonight 

Yes, my camera does exactly the same thing, I was always puzzled why it showed 0 deg C initially, my Rising Cam version always displays an initial temp closer to ambient.

[Stuart1971]

2 minutes ago, tomato said:

Yes, my camera does exactly the same thing, I was always puzzled why it showed 0 deg C initially, my Rising Cam version always displays an initial temp closer to ambient.

The QHY as soon as you add the power it auto cools to zero, or there abouts..that’s normal..

[tomato]

10 hours ago, Stuart1971 said:

The QHY as soon as you add the power it auto cools to zero, or there abouts..that’s normal..

Is that independent of NINA displaying the cooling power? Mine shows zero % cooling when connected to NINA but the cooler must be on to bring it to 0 deg C.

[Richard_]

1 hour ago, tomato said:

Is that independent of NINA displaying the cooling power? Mine shows zero % cooling when connected to NINA but the cooler must be on to bring it to 0 deg C.

That's right, my camera does the same thing. I'm sure I read about this somewhere but I can't find anything online.

The other thing that is automatic and cannot be controlled on the QHY268M is the dew heater ring built in front of the camera. ASI2600 user's can switch it on or off, but we QHY users cannot. 

[tomato]

Good to know, the Rising Cam dew heater can be switched on or off in NINA, but it’s not up to much, I had to fit a ZWO external heater to stop the sensor window misting up.

[Stuart1971]

I had 45 mins at the end of my session last night, and after seeing @Richard_ Rosette above, and being very impressed, I thought I would turn the scope to the same Target, so this is 15x3 min subs, with my new 3nm Optolong SHO filters, this is just the Ha. I wasn’t expecting much for 45 mins, but was totally surprised…

Esprit 100 on CEM70, QHY238m guided with Whitecat 51 with ASI178m

 

 

Edited January 10 by Stuart1971

[Richard_]

48 minutes ago, Stuart1971 said:

I had 45 mins at the end of my session last night, and after seeing @Richard_ Rosette above, and being very impressed, I thought I would turn the scope to the same Target, so this is 15x3 min subs, with my new 3nm Optolong SHO filters, this is just the Ha. I wasn’t expecting much for 45 mins, but was totally surprised…

Esprit 100 on CEM70, QHY238m guided with Whitecat 51 with ASI178m

 

Looks brilliant Stu! It's surprising how bright it is. I think you have the perfect focal length for framing without having to do a mosaic. I'm looking forward to seeing you complete this with S and O

I managed to image again last night. Seeing conditions were still meh, so I did one round of LRGB on M33 and moved back to the Rosette once it cleared the top of the trees in the garden. I managed to grab some S and O data for both panels, so I should be able to have a go at a SHO mosaic tonight just to see how it's coming along 

[Stuart1971]

22 minutes ago, Richard_ said:

Looks brilliant Stu! It's surprising how bright it is. I think you have the perfect focal length for framing without having to do a mosaic. I'm looking forward to seeing you complete this with S and O

I managed to image again last night. Seeing conditions were still meh, so I did one round of LRGB on M33 and moved back to the Rosette once it cleared the top of the trees in the garden. I managed to grab some S and O data for both panels, so I should be able to have a go at a SHO mosaic tonight just to see how it's coming along 

 

Thanks , Yes me too now, after seeing what just 45 mins gets me, I’m thinking what will 6-8 hours bring..

I am very impressed with these 3nm Optolong SHO filters too, no gradient at all to speak of, and I am in bortle 7ish zone..

Onwards and upwards…

[tomato]

Powered up the 268c tonight, initially showing -56 deg C😳, this slowly “warmed” to -6 deg C, over an hour, cooler power at 0% throughtout. I then set it to cool to -10 over 10 minutes, this it did, requiring 1.6% cooling power to do so, which is definitely not right. I will update the driver and see what this does…

[Richard_]

40 minutes ago, tomato said:

Powered up the 268c tonight, initially showing -56 deg C😳, this slowly “warmed” to -6 deg C, over an hour, cooler power at 0% throughtout. I then set it to cool to -10 over 10 minutes, this it did, requiring 1.6% cooling power to do so, which is definitely not right. I will update the driver and see what this does…

You're meant to set the Gain to 56, not the temperature 😂 /s

All joking aside, that sounds annoying. I remember seeing weird numbers on the humidity and stuff in NINA with this camera when I had it new. I had to reinstall the "all in one" driver package a number of times before it all worked a-OK. Hopefully the driver update solves the problem! 

[Richard_]

I now have some S and O data on the Rosette nebula. Details on acquisitions below, just so people have an idea of what equipment was used other than the camera to capture this.

I made two attempts of processing the Rosette as SHO: the first was a typical Hubble palette, the other was a "colour accurate" version using the ColourMapping script in PixInsight. The images look OK, but there is too much noise after stretching and boosting colour saturation (looks a bit deep fried lol) so I want to get some more integration time before spending any more time doing any further processing. Also, I messed up with balancing the integration times between the panels so I want to balance these better whilst imaging tonight.

The images below are just the mono master lights after merging the two panels, registering each channel, cropping and applying an automatic screen transfer function. No additional processing was performed on these images like my H example above, so you can treat these as "straight out of the camera" if you wish. The mosaic merge is horizontally through the middle of the open cluster NGC 2244. The joins are virtually invisible. You can only really see the merge if you look closely at the OIII data where Panel 1 exhibits less background noise than Panel 2 (at half the integration time, that's hardly a surprise). Nothing NoiseXterminator can't handle but I'd rather fix this with balancing the integration time first.

Data is looking good, just want need more of it

Telescope

• WO FLT120 with x0.8 reducer (effective focal length of 624mm at f/5.2)

Filters

• Antlia EDGE 4.5nm, 36mm unmounted

Camera Settings

• Mode #1
• Gain = 56
• Offset = 25
• Cooling = -5C

Panel 1 (bottom half)

• S  = 18 x 5min = 90mins
• H = 15 x 5min = 75mins
• O = 10 x 5min = 50mins
• Total = 3hr 35mins

Panel 2 (top half)

• S  = 18 x 5min = 90mins
• H = 19 x 5min = 90mins
• O = 18 x 5min = 90mins
• Total = 4hr 30mins

S

 

H

 

O

[tomato]

Updated driver has made no difference to my sensor temp anomaly on the QHY268c. It still shows -25 on start up and won’t go above -16 even with no cooling. Voltage to the camera looks good so I have submitted a ticket to the tech help centre at QHY, will keep this thread updated.

[tomato]

I have received a prompt reply from QHY, they suspect a fault with the temperature control system, but have asked for more information (screenshot of the temperature interface) which I will sort out this morning. 
I’ll contact Bern at Modern Astronomy (where I purchased the camera) to see if they can assist with returning it to China, as that looks like where this is going.

[Stuart1971]

2 minutes ago, tomato said:

I have received a prompt reply from QHY, they suspect a fault with the temperature control system, but have asked for more information (screenshot of the temperature interface) which I will sort out this morning. 
I’ll contact Bern at Modern Astronomy (where I purchased the camera) to see if they can assist with returning it to China, as that looks like where this is going.

Bern will sort you out, he is a top bloke, and very helpful…👍🏻

[tomato]

Yes, +1 for Bern at Modern Astronomy, he selflessly pointed me in the right direction 10 years ago when I had a wad of cash and not much idea.

As for the errant temp control on my camera, I took it off the scope, brought it in the house this morning and let it warm up to ambient as it was still 0 deg C in the dome. I powered it up with the QHY supplied 12V power supply, connected to EZCAP and wouldn't you know it, the temp control is working fine! It cooled to the set point, would warm back up when I raised the set point and then cool back down when I lowered it, all the values making sense.

I warmed it back up to+5 deg C then connected to NINA, all good except for this short lived spike in cooler power:

It quickly recovered, and continued cooling to the set pt and is controlling rock steady from then on. I have seen a couple of these spikes in the past, anybody else  seen them?

So, is it my dome PS? I doubt it, all the other kit runs off it OK and I've never seen a problem with this camera before or the QHY268M for that matter. OK the camera started off at a positive temperature this morning, rather then -1 or 0 deg C in the dome, but the camera has seen these conditions several times in the past without a problem. I'll put it back on the scope now and see how it behaves...