Best Lenses for DSLR Widefield

[Gina]

I wonder how a 400mm camera lens compares with the ST80 scope There's an enormous difference in price.

[Viv]

Hope to be able to find out soon Gina !

If these (arghhh) clouds clear ...........

So many things I want to try and image / attempt, just not enough clear ones.

[Gina]

I know just what you mean We've had barely a handful of clear nights since the year began! I too have lots of things to try. Haven't even got my PA right yet - there always seems to be cloud to the north even if the sky is clear generally. Got to get guiding sorted out too - not even had a chance to try that yet! There's so many things wrong with my set up that need sorting out!

[Viv]

Don't fret - we'll both soon be posting pics, worthy of our set ups.

I was dreading attempting guiding, but it really is straight forward & easy. It all seems to be in picking the right guide star. I have some advance option settings to try as well - see what difference they make.

[Psychobilly]

Its the handful of clear nights that are causing me to move awah from single use scopes towards multi use lenses...

I just wish I had made the decision sooner...

Peter...

[JamesF]

I'd hazard a guess that the 400mm lens might well have far higher quality optics than an ST80

James

[Viv]

Lots more options open then ....

Would love to try some wire wool night shots / light trails - maybe when it's a little warmer.

[GlassWalker]

GlassWalker, thanks for those excellent examples. Why are the stars in the f/1.8 shot so blurred? This is exactly the colourful distortion I was experiencing. I'll try stopping down next time.

I got some coloured blobs in some of the images which must have been the internal reflections. I guessed that was the case

Lenses are not perfect. The more you pay, the closer they might get. In the example of the EF 50mm f/1.8 II, I've found that lens is pretty good in the middle, but degrades as you go towards the edges. I also have the "slightly" more expensive Zeiss 2/50 makro-planar, and that keeps the stars a lot tighter throughout the whole frame.

Also, are you using protection filters on the lens? If so, remove it. This is one of those cases where they are likely to cause unwanted reflections.

I wonder how a 400mm camera lens compares with the ST80 scope There's an enormous difference in price.

Which specific scope as I see a few scopes of that model name? A decent scope should be better than a camera lens of similar specification, and at lower cost. Scopes can be optimised for the task. Camera lenses are much more complicated, needing to focus from near to far, and even doing that with varying focal length. Throw in even more cost for AF motors, something to drive the aperture and maybe an image stabilisation system, and it all adds up!

[Gina]

I was thinking of the Skywatcher Startravel 80 OTA :- First Light Optics - Skywatcher Startravel 80 OTA

[RikM]

The ST80 is a better guide scope than imaging scope. f/5 achromat!

I have seen some very nice images taken through these, but they probably involved a lot of TLC at the processing stage, by people who know what they're doing, before being let out in public.

[jgs001]

Rik has summed it up, the st80 will do but it's hardly ideal for imaging with. You can use filters to help with the aberrations. That's one of the reasons it's so cheap. As is focusing performance an image stabilisation a major factor in cost compared to camera lenses on the same range.