Stuart1971

Ok, sorry, my bad…👍🏼

You can set your backlash comp, in PHD2, no need to set it In The driver 👍🏼

You have not got the settings set to show…

Many thanks for your reply, and I too could not see the walking noise, in the calibrated version, but I wanted a more professional eye, such as yourself, to comment, so thanks for that….👍🏼

Ok, these are two crops of the same image, the first one was just stacked and no calibration frames at all, and you see the FPN / walking noise, and hot pixels, the second was stacked just using Darks, and the FPN has all but gone, no dithering, so do Darks help with this type of noise, at it seems it does. the image is very noisy due to height LP and shot under the moon, and very few subs…

They are still excellent mounts, and I don’t regret buying it at all, I got second hand and I knew about the reputation… I too have considered the CEM120, not seen the latest price increases…has it gone up a lot then…??

I have no choose but to use RA only, if I continue to guide in only one direction in DEC…correct…? I can’t dither in both directions and guide in just one direction in DEC, it’s one or the other….

Sorry confused, not sure what you are saying here, you mean I should not guide in one direction, or I can but I will have to either in RA only, as it will not work in DEC due to the setting I have for the DEC guiding…

No, the older EQ8 suffered from terrible DEC backlash due to not absolutely perfect round worm wheel, mine has barely any backlash around half of the worm, and some on the other half, it’s a known issue with them….and one that has had many a thread discussing it, and apparently the later ones are not much better….😮

Yes, that what I said, I can still guide in one direction, and just dither in RA only, and this DOC confirms this….yes…?

This is what is says on the NINA site re dithering in RA only…

I did, and it told me I have 3200ms of backlash and to guide in one direction only, and this has worked really well…..🤔

Yes, under the graph at the right hand end you will see a drop down box, which has three settings, the default is Auto, and you also have North only or south only, so if it drifted north after a few min test, then you select south, but you have to swap it round after a flip.

No, if I have it set on south or North guide only I have to use RA only for dither, well that’s what I have read on the NINA website anyway…

Thanks, so as I guide in one direction only because of DEC backlash and this works very well, I see I can dither in RA only, is this not as good, or is it at least better than nothing…?

Another option, which I do, is to guide on DEC in one direction only, this makes the DEC backlash issue moot, so my PA is about 3 arc mins out, so I watched to see which way the DEC drifts without guiding on, and set it to guide just in the opposite direction, so no swapping from one to another so no backlash issue, it works extremely well with mounds with DEC backlash which my EQ8 has 3200ms of….

Well, thank you very much, appreciated….finally getting some good results with this QHY268c, after a couple of months, thinking I had made a mistake buying it…👍🏼

I have been imaging for a while now, and getting fairly decent results, but have been told I need to dither, now I never have, I image with a QHY268c with the IMX571 sensor, and it’s really low noise, I have noticed a bit of walking noise, I think it’s called, where it looks like streaks across the images, when stacked with no calibration frames, but not in the final calibrated images out of APP, now people say that darks are not needed with this camera, and other say to use them, I do use them, as well as flats and dark flats, and seems to work well, so my question what is dithering, and do I need to do it..??? here is an example of my latest image of the Heart nebula, with the above calibration frames, 5 hours of 2 min subs, 50 darks, 50 flats and 50 dark flats, processed in APP with a final tweak in affinity Photo, so more data I’d needed for sure as it’s still quite noisy, but will dithering make any difference to this image had I don’t it at the time…??

Thanks, I think….🤔🤔😂

The PA figure is, well in my experience anyway, also read it in another forum, but if it works for you….👍🏼

Looks good to me…👍🏼

The PA algorithm in PHD2 is pretty much useless, it just does not work at all, so this should be ignored. I ran guiding assistant two nights ago, twice in pretty much succession, in very close parts of the sky and got 3 arc mins error the first time. And 14.7 the second….it’s just a waste of time taking any notice of it….in Sharpcap I am approx 2 arc mins off the NCP…so the figure above don’t surprise me….

No need for it to be level, close is good enough, PA does the rest….don’t sweat over it….👍🏼

Correct, it makes no difference at all if the mount is level, as that’s what PA corrects, close is good, but that’s all you need…no point in spending time on getting an EQ mount perfectly level….many people just do not realise this….👍🏼

Had another go at the Heart Nebula last night, under full moon with the Optolong L-Extreme Duo Ha, OIII filter, with QHY268c 5 hours of 2 min subs, full image and a crop of the centre region