what is the recommended imaging resolution ?

[red dwalf]

would i be correct it thinking that the best imaging resolution with scope and camera is somewhere between 1" and 2" per pixel ? and does it make any difference if you image from a light polluted area ? 

[symmetal]

Yes, 1" to 2" per pixel is the accepted optimum imaging resolution for long exposure imaging at your 'average' imaging site. At the top of mountains or in areas of stable air you can manage higher resolutions. Adaptive optics can also enable higher resolution but that's too costly for most people. 

Light pollution itself won't affect the resolution but in built up areas (particularly cities) where light pollution is generally found, there will normally be more thermal air currents about, which would likely cause a lowering of the resolution obtainable.

Alan

[ollypenrice]

I have found that, at one end, 3.5"PP is still OK in that it gives smooth round stars and no other signs of pixelation at full size. Beyond that it starts to show. If you're doing widefield at this resolution it will give a nice result but it won't let you crop to present a small object in detail. At the other end of the scale I found no real difference in captured detail between 6.2 and 0.9"PP so I'm happy to call it a day at 0.9. However, to get 0.9 to capture more real detail than 1.8 you have to have a good stable night of steady seeing. If you don't have that then you'd do just as well with 1.8. (Mono cam users can shoot luminance on the nights of best seeing and colour on the poor ones.) These are all resolutions at which I've imaged extensively. So, yes, 1 to 2 is sensible enough but it can also be target specific and a small chip working at low resolution will be a lot less satisfying than a large one at the same resolution once you consider what the picture itself is all about. In other words the raw numbers don't tell all the story.

Olly

[Alien 13]

The optimum resolution is obviously very different with "lucky" planetary or lunar imaging, 0.25 or lower being ok.

Alan

[wimvb]

In my limited experience processing images at various resolutions, I've always found it easier to tease out more detail when the images were oversampled rather than undersampled. Also, if your main interest is galaxies, it's better to keep in the "/pixel low range. For nebulae it's probably less critical.