M11 - I'm struggling

[Helen]

This is from 14 30s subs (it then disappeared behind a tree!). I can't seem to get it sharp. Is it because of movement/rotation? or is there a processing trick I'm missing?

Thanks

Helen

[SteveL]

Use some unsharp mask on that image to bring the stars out. As for why they are not sharp in teh first place, I`m not sure sorry

[Helen]

Thanks Steve, I'll give it a go!

Helen

[centroid]

I don't thinks its that much out of focus Helen.

I think a little more exposure was required (more or longer subs), to bring out the feinter stars in the cluster.

Also bear in mind that the image that comes out of the camera, has zero processing applied to it, and as a minimum, some degree of sharpening will be necessary.

As Steve says, try using 'Unsharp Masking'. This is more controllable than straight forward sharpening. Keep the 'radius' small (less than 1 pixel), the 'threshold' at zero, and 'crank up' the sharpening to bring out the finer detail in the iamge. Too much, and you will start to introduce too much noise, and possibly dark halos around stars.

The more images you have in the 'stack', and the longer the exposure, the more agressive you can be with the processing, before the 'noise' start to become objectionable.

Dave

P.S. applying DDP, can be very effective with cluster images.

[geppetto]

I think it's a very nice image Helen...

Had a bit of a play with unsharp masking and levels...

[SteveL]

[Helen]

Thanks guys. :salute: There is obviously some room for improvement in my processing I'll give it another go! and let you know how I get on

Helen