andyrawlins

FLO are now selling a low profile nose piece for the ZWO planetary cameras (I have a 224 MC) which allows me to easily get focus without a Barlow and just about get a full disc. Its one downside is that the nosepiece is not threaded for filters, its just baffled, so if you want to use it for normal work you will need to swap it out again. Its £29 which is a little steep but I guess they have had to commission it specially and it does what it says on the tin! I've put a full review on the product page: https://www.firstlightoptics.com/adapters/astro-essentials-low-profile-camera-adapter-for-zwo-planetary-cameras.html

Ah I read this wrong I think - there is currently not enough inwards movement available to get the camera into focus with a PST so this will make it worse. Very interesting though and I'll bear it in mind should I get a solar scope more suited to imaging

Thank you! I also need to get an ASI 120mm mini I think as my 224MC needs a Barlow and then I can't get the whole disk in. Plus its colour... Great articles thanks, I have them bookmarked so will refer to them when I have the kit I need

Very interesting, thanks Nicolàs. Re the ADC, I think I'll get one of those but am curious about how focus is achieved. With these small scopes (I also have a PST) the difficulty is getting the sensor close enough to reach focus. The ADC would appear to move it significantly further away. Presumably it moves the focus point with it somehow? Andy

Brilliant, thanks for that info

Great picture thanks I’ve been struggling with Autostakkert! (V4) a bit with solar. Have you been using any particular settings apart from surface? How many alignment points are you using ? I really like how you have got a 3D effect there. I don’t quite get a full disc with my current setup but ny tips on how to enhance that globe effect? I have the standard PST btw, no double stack.

I eventually solved this. It was Third Axis balancing. I came across this by chance - I had never heard of it before which amazes me because its so fundamental. Maybe for a small refractor its fine but for a biggish Newtonian stretching the mount towards its limit it makes a huge difference. All I needed to do was rotate the tube so that the centre of gravity was in line with the axis of the mount (rather than having say all the weight of the focuser, finder etc on one side) and all of a sudden it tracks very well and also finds targets much better. Its difficult to describe in words but there are some great videos out there explaining the issue and how to solve it. If I can re-find the one that solved this for me I'll post the link.

Hi All, I'm looking for some advice about how to keep my subject in frame when imaging the moon. I'm using a 1200mm f6 Newtonian on a HEQ5 Rowan with a 3x Televue Barlow, so 3600mm focal length ,and an ASI 224MC camera. I am polar aligning with an iPolar which does seem to have issues with camera centering so I re-align when I'm at my target so polar alignment should be good. When imaging at this focal length with an IR pass filter, which gives the best results, I'm only getting 25fps so to get 15000 frames takes 10 minutes. The problem is, in this time, the image shifts and I lose some of the things I want to image. The stacking takes care of this but I do lose some of my image, or at least the quality of the area at the edges of the image (I stack with ASI Studio which I find the best but I'm not sure how it deals with a shifting image) . I can't use guiding as far as I know as obviously the moon is moving faster than the stars. I can, and do, manually re-center the image during capture but this isn't ideal for several reasons. So my questions: I s some drift to be expected with this mount/focal length or do I have a problem with the mount? If drift is to be expected, what do i do about it? Obviously I can lower the focal length or just crop the image but that isn't fixing things, its just putting up with them. I'd be grateful to hear what others are doing. Cheers Andy

I had to look that term up but thanks

Thanks all. I'm using my current Barlow and it seems OK. My question is really whether a 'premium' Barlow will make an appreciable difference over a 'standard' one. I have only ever used the one I have and would be prepared to spend £100 or whatever if its going to make a big difference, but don't want to waste my money if it won't. I have nothing to compare it to. vlaiv recommended 2.5x here

Hi all. I have an 8" reflector which I use visually mainly with Vixen LV 5&12mm objectives. I also have a 'no name' 25mm and a no name 2xBarlow that came with the telescope. The Barlow seems OK. If I visually compare the 5mm on its own with the 12mm plus Barlow there is little if any difference in quality on Moon or planets. However, I have started imaging with an ASI 224mc that I believe is ideally used with a 2.5x Barlow (reflector is 1200mm f6) So to my question: does the fact that I can't see any obvious image degradation visually with the Barlow mean that it is good enough for imaging too? What is the difference between an ok Barlow and a premium one? Should I upgrade to a better one or a Powemate? Recommendations gratefully received. Cheers in advance

I got the iPolar with the HEQ adaptor to go on my new HEQ5 Rowan which is 'on the way'. It doesn't directly fit the Vixen mount (too small) but I managed to make a collar or washer out of a stiff foam which allows me to seat it quite firmly and reasonably accurately - more than enough for my needs. The iPolar worked a treat (once I entered long and lat the right way round) and the Starbook worked like a deamon finding targets with better than ever precision. So it looks like after 16 years of owning it I've finally found out how to use it properly, just in time to replace it with the HEQ5 I took the Dec axis apart cleaned and re-greased it. Actually the grease in it wasn't too bad and I had quite a bit of trouble getting it back together just tight enough to work properly. I think what made more difference was carefully adjusting the worm gear. The whole thing now moves far more smoothly and quietly. There still seems to be a vibration which renders it useless for long exposures but that may be due to overloading. It will probably spend its retirement as a posh equatorial mount for my DSLR.

Brilliant thanks Pete - I knew I'd heard something about it 'hunting'. I can't use a polar scope (because I don't have on and because of my knees if I did) but am planning to get an iPolar for my new mount. They don't do an adaptor for Vixen GP but would you happen to know if it is compatible with other mounts.? I seem to remember hearing that you can use another make of polar scope (maybe Skywatcher) on them so an adaptor of that make should do the trick. Polemaster do a Vixen adaptor but they are more expensive and people seem to prefer iPolar.

I have just had another fiddle with the mount with and without the scope on. The vibrations in the dec axis are there all the time at a low level but much worse with the scope on. (which is a big metal tube after all) The dec motor was slightly loose in its mounting which I have tightened. However, the dec axis is incredibly stiff, with the RA one not much better. Does anyone have any instructions for servicing this mount? I assume its a case of take it apart, clean re-grease and reassemble but that may be easier said than done

Have you got yours on their 1.75" tripod? Their mounts seem to come by default on a 1.5" but FLO recommended the 1.75" even for the GEM28 which puts the price up.