Cygnus with new (to me) lens

[Scott]

I took this last night with a 24-200mm vivitar lens on my modded 1100d mounted on astrotrac. 6 X 600 lights and darks only.

Stars are shocking the further you move away from the centre. Need to back off the f/ratio.

Still, what can you expect with a £10 lens

28mm process1 by Scott Prideaux 1961, on Flickr

[DirkSteele]

What f/ratio did you use?

[Scott]

f/3.5. am I right in thinking that the f/ratio in byeos doesn't matter when the lens is set manually?

[Alien 13]

Good result its always worth  a punt with these types of lenses some real gems out there.

Alan

[wxsatuser]

You don't know unless you try, looks reasonable and Astrotrac works well.

[bogdog]

nice pic.

liked the tandem sattelite trails from top left  down through centre

[mikeyscope]

Very nice result for an inexpensive lens, however yes better to close the lens down for better quality star images, I tend to set aperture as a priority around f7 give or take an f-stop, most lenses give their best to the corners of the frame at these settings.

On  a driven mount you have the advantage to take longer exposures ...to a point before noise builds up, not sure what ISO you used but 600 secs is a reasonable maximum for a non-cooled camera give or take some seconds depending on local conditions. 

Of course photographing auroras for instance you do need to open the lens up as far as optics allow, for these type of subjects you would have to put up with poorer star images at corners of frame.

[robbie c]

Looks like you got a great bargain nice image 

[Pete Presland]

looks very nice to me, good colour and star shape.

[jgs001]

Looks pretty good Scott, I reckon you got a bargain there... I can't tell, but you may be able to recover the edges somewhat with the lens correction tool in PS (use that for my ED80 images to 'flatten the field', as it were ).

[Knight of Clear Skies]

 Looking good, must be satisfying to take a bargin bin lens and get that out of it.

f/3.5. am I right in thinking that the f/ratio in byeos doesn't matter when the lens is set manually?

It shouldn't do, as the aperture is on the lens rather than the camera. I can't imagine BYeos does anything else with that information, although for reference it might store it in it's output files.