Rob_Jn

40 minutes ago, Stuart1971 said:

Wouldnt the cotton wool get saturated before the desiccant, which would then get back in the chamber….??

The cotton wool is just stop any dust getting into the chamber from the mol sieve. The sieve I use came from a lab I used to work in and is a high quality grade, I can’t vouch for the dustiness of what’s available now but I think the dust risk with a cotton wool plug is low. I’ve used mol sieve on all my cameras for the past few years, lasts longer than silica gel and just as easy to regenerate.

Yeah, you have to make sure you have a decent plug of cotton wool in the tube first.

If you’re still using the pale pink silica gel desiccant supplied with the camera then ditch it. As mentioned in one of the messages  use molecular sieve 4A. After a couple of days my RH dropped to 24% a bit extreme but it would ensure your chamber was thoroughly dried out. After a week or two the RH increased to 60% which says the chamber is not sealed effectively. I run it at about 65% at -10C and never had the dark spot problem.

I’ll give it a go and see what comes out …..

Just wondering if anyone else sees these specs in their cooler fins, is it dirt or surface mount components ☺️ if it’s dirt should I carefully clean out? Could be something from a nearby conifer. Never noticed them before.

I’ve been working on images of M81 and M100 LRGB mode 0, gain 26 offset 30 with 60s subs at f5 and neither show the cores burned out. Hope it’s clear for you 😉

Rob

Molecular sieve is capable of reducing the humidity to ~20% whereas silica gel is higher, from memory around 40%. The Atik cameras use mol sieve tablets and I think some ZWO cameras too. 4A sieve is usually recommended for moisture absorption but 3A will work.

(not that you need to go down to 20% in this camera 😊)

Looks like a comms  issue to me, have you tried connecting the camera directly to a pc with a short usb lead? It works fine on usb 2.0 with downloads of about 2s. The other thing you could try is using the QHY app, very basic but it might reveal something if the images are ok. I received mine in June and didn’t have any problems with driver installation.

The Ha filter should centre up with the electronics on the filter wheel so I’m a bit puzzled why it should appear to be out of centre. Perhaps try the reproducibility of the centering a few times and see what you get, applies to all the filters as well.

The masks look good either option, I was thinking just knock one up out of black card to test the concept before you spend the money. 

Congratulations on the new camera 😊 I would try and get a few images to calibrate and see how they work out, but the SHO flats do look unusual, the Ha appears to be off centre. You could try making a mask for one filter and see if it has an effect before you invest in a full mask.

Thanks Steve, I would think if you can use ROI for planetary etc. it should work for longer exposures, I’ll dig a bit more to see if I can find out.

Hope I’m not off topic here but I’m considering buying the QHY268M and would like to know if I can hardware bin 2x2 and also does the camera support ROI for deep sky imaging? The ASI2600MM supports both in their specs.

thanks,

Rob

37 minutes ago, kirkster501 said:

Set the Ephemeris time to 10 days.  30 days does not work.

Brilliant, thanks that worked 😊👍

Anyone got a good ephemeris for JWST, I get an error on JPL Horizons 😐 tried quite a few settings but all the same error message

Phew, I have succeeded in cleaning it without removing the lens but took a soft lens cloth on a rod and gently tried rubbing a small area and it seemed to clean up, carried on very carefully and although it’s not perfect it’s nearly back to normal ( most of the dust you can see is on the outside now 😊) I suspect I’ve been very lucky in that it has started to develop recently with the onset of damp and cold weather. Lesson learned though I’ll be keeping it indoors from now on. 

thanks for all the advice guys,

Rob

I’m glad something good has come out of my troubles Mike, William Optics are well known over here, I’ve had the 72FD for 10 years or so and it’s always performed very well.

I’ll probably expose to some UV as Jonk has suggested (we have a uv exposure frame where I work in the absence of sunlight at the moment!) but very carefully, I don’t want to degrade the paintwork.

Rob

Yeah I thought it looked a bit more suspicious, worried that it might be between the lens elements 😒

I’ve come to use my WO72FD after some months stored in my observing shed in a case and found a deposit on the inner surface of the lens. I’ve tried blowing warm air down the tube thinking it was just condensation but no luck. I can get the dew cap back to reveal the lens housing which has a grub screw in. I removed the grub screw thinking the lens housing might screw off but no luck. Anyone know if it should screw off or will I have to clean the inner surface down the tube? 
thanks,

Rob

Thanks 😊

I meant to mention JPL had the predicted mag as 14 but I think it was more like 15-16, maybe 14 in the ‘glints’.

NASA updated the story yesterday.

https://www.jpl.nasa.gov/news/news.php?feature=7795&utm_source=iContact&utm_medium=email&utm_campaign=nasajpl&utm_content=daily20201202-1
 

confirming the spectrum matches another Centaur stage wandering about up there 😊

Managed to catch this last night moving eastwards across Gemini as it passed close to the Earth. This has been designated an asteroid but is in all probability the upper stage of the Centaur rocket that launched the ill-fated Surveyor to the Moon in 1966. I think the image confirms this is man made as it appears to be tumbling and possibly glinting in the moonlight every ~10s.

This is a gif of 3 frames 60s each through my 12" f5 reflector, 23:10 to 23:12UT.

https://en.wikipedia.org/wiki/2020_SO

I’m a bit limited with where I can mount the camera so couldn’t guarantee I might not get some illumination down the tube but I might be able to rig up a nearby post perhaps? The Amazon blink looks a good choice. 
Ah the SPC900  😊 can’t get hold of one now it seems, my old ToUcam probably would have done the job but it packed  in a few years ago.

thanks for the ideas guys

I’m imaging and the CCD is very sensitive to IR, ok most filters block most of the IR but I don’t like the thought of illuminating my rig with IR.

Do you get any problems?

I’m looking to place a webcam to monitor my telescope while it’s operating automatically to make sure nothing untoward is happening.

Can anyone recommend a webcam for doing this? The security types I’ve looked at all seem to have IR illumination fitted and the one I have for general use can’t see a thing in the dark.

thanks,

Rob

A very nice image, I would be very pleased with that too, agree on the more delicate processing approach.

Bought an OIII a couple of months go but haven't used it yet to do some HOO the rosette is probaby too far to the west now.

Thanks 🙂 I like the drawing, it's certainly less stressful than imaging!