robster

Nice pic! It's sharp in the middle, and soft round the edges - you need a Coma corrector or field flattener - a bit pricey, but essential for getting an in focus image across the frame when used with a DSLR / telescope combo.

Hi, I've been trying to get a good shot of Andromeda for ages, but have been blighted by clouds, weather, work and all sorts. Last night was clear over Exmoor, although the moon was out, so I went out early. Unfortunately, just as I started capturing, my blessed pager went, and I had to dash out, in my haste, I knocked the focus out of my camera, and 200+ lights were ruined. 🥵 Anyway, hopefully the sky is clear again tonight, but I have some questions.... 1) The moon will be bigger and brighter tonight - will this be an issue, and if not, what camera settings should I use. 2) I intend to use my Canon 5DMkIV (full frame DSLR) with a 400mm f5.6 lens and take around 150 to 200 lights at 30 seconds at ISO 800. Is this about right, or should I be increasing the exposure time? 3) I also have a f2.8 200mm lens which I can use with a 1.4X teleconverter to give me 280mm at f4 -would 200mm or 280mm be a better option? Thanks!!

It's a professional sports camera (not that I use if for that, but it is ideally suited to my professional needs, which is why I have it). I guess most sports 'togs don't do 30s exposures!!!! Yes - it does have a bulb setting, so I've ordered a cheap intervalometer - might get it this side of next Easter if I'm lucky......Betelguese will have probably supanova'd by the time it arrives 🤣

Thanks Billy. Intervalometer on it's way!! I had thought of about 2 hrs of subs, so I was in the right ball park. Optical train is the same, so all OK there. Thanks

Thanks for the lovely replies....but any suggestions what I do about the limitation to 30s? Thanks!!!

Thanks Pankaj! It was 100 X 10s exposures at ISO1600, 50 darks, 50 bias and 50 flats. Stacked in DSS and processed in PS. The optics of that lens though and the quality of that camera are truely astounding.

Hi, I'm new to Astrophotography, but been bitten by the bug (see attached last night's attemt at M42 and friends, that I'm quite happy with for my second ever DSO picture!). My work involves me having a Sony A9 Mk II and in the kit are a whole load of lenses, indluding a F5.6 200-600mm zoom. This is an exeptional camera, and I'm very lucky to have use of it. It's this setup that I did the M42 shot of. As the weather will be clear again tonight, I want to attempt the Rosette Nebula. The problem is that my camera's maximum shutter speed is 30s - and most people are advising somewhere between 30 and 100 shots at between 120s and 240s (ISO1600). I see my choces as being: 1) Shoot more lights at a maximum exposure of 30s each 2) Increase the ISO to 6400 (noise is pretty good on this camera, even with all noise reduction switched off) 3) A combination of 1 and 2 above. There are a few aftermarket interval timers, that may allow longer shutter times, but I can't get one in time for this evening!! Thoughts? Thanks Rob

Hi, I’m a bit of a newbie, I’m afraid, and I'm struggling to get my polar alignment right, despite watching a load of you tibe videos etc.. The process I follow is : 1) Get the HA from either the PS Align App or from my synscan handset 2) Line the polar scope up so that polaris is right at the bottom of the reticule 3) Set the RA ring to zero 4) Rotate RA using the northern hemisphere calibrations to the HA. I have used the PS Align app to get my HA – it reports, say 8:22.2, which is the same as my synscan handset reports. However, the reticule display on the app, shows Polaris at just below the nine oclock position (assuming a 12 hour clock face; see image:). If, however, I use the HA of 8:22.2 on my EQ mount, the position of polaris is nowhere near that as represented on the app. I have started with Polaris at the zero position (straight down the the reticule) and am definitely using the Norther hemisphere HA ring on the mount. It's definatley not just inverted - I've tried that!! Any advice appreciated?

Borrowed a camera from work for the weekend and mounted on my EQ5GT mount. Polar alignment was rubbish because I was rushing. This was my first time using anything like deep sky stacker, and the first time I've taken a photo of the sky. I was fairly impressed with the results, although I didn't seem to get the flat files right, so I didn't use them - 100 lights, 50 bias and 50 darks. Sony A9II with a 200-600 f5.6-6.3 lens set at the long end. ISO800, Shutter speed of six seconds.