abmwinnoch

10 minutes ago, ONIKKINEN said:

Fewer pixels so the filesize is smaller naturally.

By the way ASI fitsview is not very useful for actual image analysis as it stretches the image with some arbitrary set value so you are not really seeing the raw data. Its better to view the image in something like Siril where you can make objective measurements on the pixel values/standard deviation/whatnot and try to make an educated guess on the sub. But ultimately i dont recommend viewing subs at all, just check their statistics when stacking (and maybe reject the worst ones) and only judge the final stack on quality.

Thank you- you've been very helpful.

1 hour ago, ONIKKINEN said:

ASTAP (free) has a binning tool which works with colour images that you can use after capture. Easiest way is to stack unbinned and bin the stack before making any adjustments. You can also batch bin your subs and then stack them, same result either way (almost).

 

Just used it and it seems to work well- much reduced noise. Much smaller file too- from 51mb down to 1.84mg- does that seem right or do I need to alter some settings in ASTAP?

1 minute ago, ONIKKINEN said:

How do you quantify the amount of noise in bin1 vs bin3? If its with a stretched file you should make sure that they have an equal stretch. You should also view both at 100%. Bin3 will have 3x signal to noise ratio or in other words be equal to a bin1 exposure of 9 times the length.

It just doesnt make sense (cannot be true) that the bin3 image is noisier.

Hmm; this was just visually looking at the subs- I admit I've not been able to capture enough 3x3 subs yet to directly compare a stacked result- below is a screenshot snip of the subs with 1x1 on the left and 3x3 on the right at the same scale. The 3x3 looks far noisier to me.

15 minutes ago, ONIKKINEN said:

ASTAP (free) has a binning tool which works with colour images that you can use after capture. Easiest way is to stack unbinned and bin the stack before making any adjustments. You can also batch bin your subs and then stack them, same result either way (almost).

 

Thanks, I've got ASTAP; i'll give that one final go, before abandoning the experiment and returning to 1x1 imaging and living with the noise.

OK, think I'll 'bin' this experiment and return to using the full resolution of the camera. I've never been able to wrap my head around the concept of throwing away a third or a quarter of the camera resolution I've paid for and I also don't understand how the focal length of telescope matters? Surely a camera is telescope agnostic in that all it's 'seeing' is an analogue image from the focuser; how can it 'know' whether this image is coming from my 360mm WO or from a reduced 2888mm focal length of the C925? It's all just billions of photons landing on the sensor. Sorry despite having it explained to me on various fora over the past year or more, still don't get it. Thanks for trying though!

1 hour ago, tomato said:

If it’s a OSC camera won’t you lose the colour data if you bin when taking the subs?

Nope full colour, but noisier than the front row of a death metal concert.🤨

1 hour ago, tomato said:

If it’s a OSC camera won’t you lose the colour data if you bin when taking the subs?

Just about to find out as I stack the meagre few frames I got before the rain. Don't think so though- sure I've tried stacking binned frames before ages ago. Will report back

16 minutes ago, scotty38 said:

so you're binning after stacking and not at acquisition time?

No- binning at acquisition time. I can't seem to get binning to work in DSS and no idea how to do it after that, so simplest for me to Bin at source.

19 minutes ago, scotty38 said:

I see what you mean, does look a bit odd. How are you binning at acquisition time?

Just trying, for the first time to use 3x3 binning as suggested above. Started doing darks with this binning level, in preparation.

11 minutes ago, Dave Matison said:

I have found that liberal dithering greatly improves the apparent noise of my 533mc pro.   I love the camera, almost as much as the 2600mc pro.

I've been dithering every 4 frames; more?

Caldwell 9-CaveLIGHT240.001002022-12-220076.fitsBetter example now it's dark. Actually I'll reserve judgment till I've stacked a few of these. Certainly the signal (target) seems nice and strong.

So, I'm currently imaging with 3x3 binninCaldwell 9-CaveLIGHT240.001002022-12-220070.fitsg and the subs look much, much noisier than 1x1; that shouldn't be should it? FITS file attached- note, it's not fully dark yet so the image is a bit of a mess but you get the idea.

16 hours ago, vlaiv said:

Do keep in mind that you need some "pre/post processing" for best results with C925 (even with focal reducer) and such small pixels.

I'd keep resulting sampling rate at around 1.5"/px in either case.

ASI294 with x0.7 reducer on C925 will give you ~0.58"/px. I would bin such data x3 after stacking and before processing

ASI533 is going to be even higher sampling at ~0.47"/px - again at least x3 bin.

If you use them natively - then bin x4.

Sorry, what do you mean by- "if you use them natively?"

1 hour ago, vlaiv said:

Looks perfectly fine.

You have to note that ASI294 has 4.63um pixel size and ASI533 has 3.76um pixel size.

That is x1.5 in signal level per pixel if they are both used on same scope. Difference can be even bigger if there is additional difference between scopes.

If you use both cameras on same scope - you need x1.5 more total imaging time with ASI533 to match 294 (if they have the same QE, and they probably do).

What scopes are you using with these cameras?

Okay that makes sense and would explain the noisier data. I should probably have considered that before buying this model- The rarity of clear, windless nights means less time per target would've been a better outcome, at least until I buy a hyperstar one day! I haven't decided which way round is best yet- 294 on the Celestron C925 (usually with with reducer) and 533 on the WO ZS61iiAPO or the other way around. In terms of framing, the 294 gives a wider field of view so would probably be better employed on the William Optics scope with the tighter, square framing of the 533 being good for framing targets like planetary nebula and galaxies.
In this case, the FITS image above was from the 533 on the WO.

Hi. On the suggestion of the good folk at FLO, I'm posting this query on here. I've just bought the ASI533MC so I can image on both my rigs at once, joining my existing ASI294MC camera.

First impressions are good; very impressed with how quickly the camera cools and maintains temp amongst other things, but one thing I have noticed is that the noise levels seem higher than my 294.  See a typical sub below. It means that I'm having to apply more noise reduction after stacking than I'm used to doing at same settings with my 294.

Does anyone who has this camera have a sub with IC 1848 - SoulLIGHT180.001202022-12-200025.fitssimilar setting to me, that they can post for comparison? I had the camera at 120 gain (though I believe 100 is a better level for this camera), cooled to -20 and this is a 180 second exposure. Just seems a bit noisy to me- wanting to check I don't have a dud or there is a setting somewhere that needs set. Thanks!

Hi, does anyone have any suggestions for the best way to dry out the reusable tiny sachets that come with this dessicant cap? https://www.firstlightoptics.com/adapters/astro-essentials-dual-fit-desiccant-cap-red.html

I'm sure that radiators are fine in the winter but now that they are off for the summer, I've tried everything from heating them gently on an induction hob, to leaving them out in the sunlight! Nothing turns those green crystals orange again fast enough to over come the speed they obsorb moisture from the air!

At best I see condensation forming inside the plastic cover, but it doesn't seem to escape fast enough. Any sensible suggestions? Thanks

Interesting! How do I go about getting/building one of those?

2 minutes ago, banjaxed said:

Those focuser knob grooves look like they would take the GT2 timing belt if you could find a way to attach the motor.

Can you elaborate please- what is the GT2?

Hi- due to a (very) extended wait for my new OTA I have been using my old TAL optics for use with my ASI294MCpro on an EQ6-R mount. With NINA / sharpcap I can run sequences and automate most aspects of imaging, bringing this 'made from Russian tanks' 1990's relic kicking and screaming into the modern astrophotographical age ! One thing I haven't tried doing with it yet is attaching an electronic focuser to it. I think the focus knob comes off, or at least turns to adjust resistance- not tried this but I'm sure I've seen this on a youtube vid. Anyway has anyone on here ever tried to remotely focus a TAL ?

23 hours ago, Viktiste said:

And try to reset your layout: options - Imaging - reset layout

You're a genius ! Just when I had all but given up. Resetting the view did it! Even though I had all windows closed, who knows what I had done. Thanks- hopefully this wont be a recurring issue.

Wow, could it be that simple? I'll give that a try later. It had occurred to me that the window could just be hidden and I thought I had closed them all but maybe not; it's quite an annoying interface in that whatever you are looking at gets covered by subsequent windows with no indication that there are other windows underneath.

To be honest, I think I'm just going to give up on NINA. I was thinking last night as I was imaging with Sharpcap, that I just don't want to waste any more precious clear-sky time messing about trying to get it to work. I'm certainly not going to mess about with drivers that are working fine with other applications. If it ain't broke and all that. The Sharpcap/PHD/Cart du Siel trio seems to do everything I need. It would've been nice to have the choice of trying another application but if it fails at the first hurdle of getting an image to display then I'm not going to waste any more time on it. Thanks for everyone's help here.

Okay I can't see that setting whilst the camera is disconnected- must just pop up when connected so I'll give that a go later.

1 minute ago, Jamgood said:

Can you not test it in the daytime on a distant object or even a blurry close object.

For the 294mc I use the defaults of 120 Gain and 30 Offset. Like I said before I did have some idle camera issues with APT, usually after a meridian flip, and dropping the USB down to 40 solved that for me. 

Sorry where is that USB setting? I meant to try that and forgot.

3 minutes ago, Clarkey said:

The only time I have had any problems with NINA and the camera is due to a dodgy connection somewhere. So an intermittent USB fault. In some cases I have had the camera stuck in the 'idle' state but will not do anything. Sometime just disconnecting and reconnecting the camera cable has worked. Other times I have had to restart everything from scratch which is a real pain. Sometimes you can connect one of the simulated cameras then disconnect and reconnect the real camera and it seems to restart. Also, try going from live view to imaging can work.

This camera issue is the only real negative I have found with NINA (along with the meaningless error messages). However, once working the benefits do outweigh the drawbacks.

Yes, this is the frustrating thing. I don't have any major issues using the combination of Sharpcap, PHD2 Cartes Du siel; they appear to get the job done as far as I can tell this early into my astrophotography journey. But many people extol the virtues of NINA, so I really want to try it! I'm not sure it's a connection issue though. Like I say, I can switch between NINA and other software all night long and I get a camera feed successfully from the other software and not NINA. It must be a NINA issue.