JonHigh

Hi. Yes I definitely hear that!!! Waited months for someone to help me but in the end I had to figure it out when the skies cleared on those rare occasions. Hate wasting on experimenting too but once it’s done it done I have been using my AA26c for ages on 100 LCG but heard the DR / read noise is better once changing it to HCG. I found that the results from using gain 100 at HCG were notably noisier. However, that said I realized after the fact was that I had kept the subs at the same length of 3mins. Probably should have drop it to 2 mins. But hey the results I’m getting are very good using LCG (as pictured) so I’m not sure sacrificing the apparent noise for a bit more DR is worth it even if you’re getting a few more subs in. Likewise I will be trying it again at some point as I will need to drop my exposures to compensate for the higher gain. Also I manually switch from LCG to HCG so I might go to 300 LCG (Ultra Low Noise mode) instead of 100 HCG? Just have to experiment further I guess.

Yup I got that for upper clamp to lock the scope down as the supplied thumb screw was too big for the RA axis to revolve. Bought from Amazon (made by Sourcing Map). I haven’t upgraded the Alt ratchet, although it could do with it but I really don’t want to spend any more on it. Looking at prices and to save £70 odd pounds, the Omegon Deluxe might be the way to go. Seems to be a solid performer.

Hi all, Thanks for all the replies. I have had another look at the skywatcher wedge last night after dismantling it. The pin for the Az was a bit loose so tightened that up! Indeed it seems better once everything is nipped up followed by small adjustments. Went slightly higher in Alt then eased it south so it’s resting on the gear and seems to be better. I think I might save up and get the WO one. However, I’m only using the Az-GTi for a light AP payload or a quick visual setup. Otherwise my modded StellarDrive HEQ5 comes out!

Cool. Thanks for that. i believe the AZGTI can handle up to 5Kg payload and I’m not putting anything too heavy on it so should be okay. The Ioptron seems to be the one to get if it doesn’t move when locking everything down. Will check out the Minitrack so thanks for all your help.

Well after some experimenting I have decided to go back to LCG at gain 100. Looks so much better to anyone else seeing this post.

https://amzn.eu/d/3kv0drE Sloppy is a good word to use. As soon as you go to lock it down PA is lost! Yes. I had to do a bit of a fix as you say to get it working. I bought a M8 x 20mm thread with a push button ratchet that worked well. I know it’s for fun in EQ mode but I have got some decent images from it. The wedge is just frustrating and flimsy as you know. I take it this is the Ioptron one… https://www.firstlightoptics.com/ioptron-mount-accessories/ioptron-alt-azimuth-adjustable-base.html?gad_source=1&gclid=CjwKCAjw26KxBhBDEiwAu6KXtxoA7i09_s7AiV0qKB67t_C7gp52irh5ZkZ77biFQv4mbmP8is7FvRoCQH0QAvD_BwE Seen the Omegon polar wedge as well if it’s any good but starting to see £200!! Seems to me that I will have to have patience and get a used WO wedge. 🙄

Thanks. Agreed, the WO does look the business. There was one on Astro Buy/sell for £120 but sold already. That’s about as much as I want to spend in all honesty. I did see the Bresser star tracker wedge but can’t find much by way of reviews other than Amazon. Will have a look at the IOptron. Can only be better than the SW offering. 😂

Hi all. Just a quick question. I have a skywatcher AZ-GTi that I have converted for use in EQ mode using the Skywatcher wedge. However it really isn’t great. Any suggestions on a decent replacement without spending a vast amount. Looked at the WO but costs the same as the mount so that’s out. Any advice would be appreciated.

Awesome. Thanks so much for your help! Really is very much appreciated! I feel like a newbie all over again!! 😂

Thanks for the detailed info. To be honest I thought it was something I may have inadvertently done to it! - I will check the back focusing spacers just in case which is an easy thing to do. However it's the collimation I don't know at all. I will get a cheshire to start with so at least I can bring it to where it should be. This was one reason why I didn't go for an RC scope and got a my Triplet some time ago now. Was thinking about selling it and getting a Newt as a replacement but I'm not so sure now. Maybe my brother should take it back but not before I have played! 🤣 Thanks again PS. Aha yes there is a central dot. Right I get it now! 🙄

Oh I see. I'm so used to my triplet, Oh the fun of newts 😂 ! I will have to check with my brother as he set it up initially so I am assuming he has set it up correctly. I will check if the distance is correct maybe an extension spacer was left off? So birdlike stars is a collimation issue? What is a backwards coma? Starting to wonder if I should just stick to my frac! Sorry for going on - Just want to understand. 👍

Thanks for the fast and sound replies! So I was going in the right direction of it being well out of collimation. Is this a Primary / secondary or both mirrors out? Yes, indeed a coma corrector was in place but I didn't think it could present an issue as long as a corrector was used? Maybe a better one is needed? This is a totally new scope to me so I'm a bit like a fish out of water! I'll have to sort this out and get it back up and running when clear again. Also need to sort out the tilt!! Birdlike Stars... If it turns out to be astigmatic is that the end of the scope?

Hi All. I hope you can advise on this. I borrowed my brother's Newtonian (SW 150PDS) to have a look if it was something worth getting as I have only ever used refractor's and Mak's. I took this 2 min sub and saved an auto stretch version in ASIFITS viewer to ask someone more knowledgable what this is? Im guessing it's a collimation issue (primary or secondary?) or is there something wrong with it optically? I first thought it was out of focus (Used a mask) although it was saying it was focused!? I assumed if it was out of focus I would get donuts rather than odd shapes? Please help.

Had a little play with this image on a bit of downtime plus the weather has been awful so...

Brian May would be pleased to see all that dust! Really excellent reprocessing. I must look into getting PI and these plug ins at some point!

That’s a great image. I had to zoom in as it didn’t look real. Very Eskimo looking! 👍🏻

Hi Alan. That's some light reading I will be doing. I love to be educated and gain (excuse the pun) knowledge especially in this hobby that I enjoy maybe too much! So thanks again for your time. I will have a look at the exposure times next time it's clear, whenever that will be. I do have a Pro Licence for SharpCap that I mainly use for PA. I recently did a Sensor Analysis which, to be honest put me on this road in the first place. But come out the other side with more understanding, so was definitely worth it! 👍 Indeed, I will check out the Smart Histogram function now I have done the SA. I live in Bortle 5/6 which is why I have never ventured further than 3 min subs for the very reason you gave. The camera side I get instinctively. Re the RedCat. Sounds like you had an awful time with it but pleased the distributor was good enough to help you! Yes agreed, I actually deleted it from this post and started it on a new one as there seemed to be an issue reinserting it as I decided to reprocessed it again.. Many thanks for your comment. 😇

Hi All, Finally got to reprocess the Soul Nebula over the weekend. I think I have tamed the noise levels in the high gain setting I used...

Alan. Thank you so very much for your time and patience. I think it has now gelled. It seems an absolute mine field, but an enjoyable learning curve especially with good people like yourself shedding light on things clearly and thoughtfully. I thought I had an understanding of sensors and how they worked but never realised how different manufacturers use different scales to describe the same thing. Almost like using imperial and metric units I guess! Either way thanks again 👍. Being an ex-pro photographer with an understanding I assume as the gain levels have risen, I take it that the exposures would need to decrease or should I continue with 3 mins subs for example? On a side note from looking at your impressive equipment list, I noticed you have WO RedCat-51. I was considering it as a possible next purchase as the Evoguide 50 I repurposed has got me into wide field captures.

So the auto switch over from LCG TO HCG on the Zwo is at 100 where it’s done manually on the Altair. So I thought I was right in using a gain value of 300 and switching it into HGC mode. As it’s a rough equivalent value? Better to use 100 in HCG which brings it up to 300 in brightness/sensitivity at a lower read noise level? Sorry about this.

Thanks again for your time Alan. Crazy. I don’t understand why the scale values are different from various manufacturers and aren’t just standardized across the board! Oh well. I use APT for image capture rather than Altair’s own software. I loaded that software up for the first time and indeed it starts at 100 (ZWO 0). Also checked APT and confirms that too, it reverts to 100 if I enter a value <100. So I’ve been using the camera at its base line. Or in ZWO terms Gain 0 in LCH mode all this time.

Hi Alan. Okay thanks for that. I think I have worked it out in my head now 🙄. Looking at the graphs and of my Sensor Analysis from SharpCap, it’s seems best to have it set at 100 using HCG mode. I will give it a try next time out and hopefully I get a better result?! Let’s face it, either way it will not be as noisy as the shot from last night!

Hi Alan. Thank you very much for your info and help. Really do appreciate it. Ah. That explains why I have a noisy image. So I was using a Gain value of 900! Blast. APT has a manual switch over for the conversion modes. So would I be right in saying that LCG at 300 is equivalent to 100 HCG. If so then the later should give better read noise results but a loss in Dynamic range and well depth? I found the graphs for the 26c and have attached them. thanks again

Hi All. Took this last night and quickly processed it in Siril and PhotoLab. Trying to work out different settings for the camera. Using HCG mode, higher gain and offset values in APT. 54 x 3 min subs, gain 300, offset 200. Switched over from LCG to HCG. Although brighter and higher SNR, I think it looks noisier than when I was shooting at gain 100 with an offset of 50 in LCH mode. I assumed it would be less noisier, maybe shorter exposures and more subs? Appreciate any advice. Can I still use LCG at 300 as the switch over is done manually? Also, It didn’t help that my EAF was slightly out of focus, something I need to have a look at. I will be looking at processing it in the Hubble Pallet this weekend for fun.

HI all. I hope someone can help me out? I have an Altair 26c that I have been using for a while now and been very happy with it as per previous images/posts I have shared. However, I think I could be doing better with regards to its settings in APT and Read Noise levels. Currently, I have been using it by and large at Gain 120, Offset 50 with about 3 Min exposures in Ultra Low noise mode and in LCG mode. I have now got a SharpCap Pro licence and ran the Sensor Analysis routine and came up this info (see attached). It would seem running the Gain level at 300 would be most beneficial. As I understand at Gain 300 is the switch over from LCG to HCG? So should I be running APT in HCG or just keep it in LCG at Gain 300? If I do change it to HCG at 300 does that correspond to '300' in both apps as I have seen that these values can change EG 300 in one app means 150 in another?? Confused! Also the Offsets in SharpCap started off with 794 should I keep to that? Hope this makes sense and appreciate any help.