Astrophotography Exposure Triangle

Hi Rupert and Mike
Thanks for all this feedback!! Much appreciated and all very interesting to improve astrophotography.

I am about to be off for the day, but a quick note to say I will look into more detail at all the above and try to incorporate some of it (perhaps I should specify Wideangle Astro in the triangle) and perhaps show some symbols for the aberration and and spikes. I had wanted to add spikes, but I didn't not want to clutter things too much.

Just to clarify that this triangle will not be used in isolation. For instance, in my presentation, I am planning to use the triangle as a basis to show what can be done with such and such combination (So for instance, high F number etc. with a picture of my spikey Moon + Jupiter + Venus from Greenwich. Or for very high ISO + Low F number + slow shutter speed, so the ETTR milky ways.

If for Flamsteed members as a standalone handout, perhaps I could include some extra info like those you pointed out. I'm happy to do that after I've finished the slides for the talk.

I will see how to fit it all in and post an additional version soon! 🙂

Enjoy the weekend!

Nice graphic Sumitra! I would love a copy of this as it’s great to have all this useful info in one easy to grab place!
Must say, I also was a little confused by the sensor signal part… Perhaps it’s just the word ‘signal?’ Clarity/detail, is that what you mean?

Hi Christina! Thanks for your comment, sorry I had not noticed your comment yesterday 🙂
Feel free to keep a copy! I might update it later when I get a chance!

I would keep the word Signal as that's the technical term that's meant here.

Thanks Sumitra! I actually referred to your lovely triangle last night as I wanted to test my camera settings. Had a VERY quick stab at making star trails. It was very helpful!

Thanks Sumitra! I actually referred to your lovely triangle last night as I wanted to test my camera settings. Had a VERY quick stab at making star trails. It was very helpful!

Yay! I am most delighted it was helpful!
So where are those star trails of yours? May we see them??

Ok… Erm, brace yourself for this… It's no work of art!!!! Not even a fully finished trail… Just wanted to test those camera settings:

Any ideas/tips on improvement, I would be most grateful for (please feel free to rip this to pieces - I will not be offended).

It's tinyyyyy! Can you put a bigger picture? 🙂 But looks nice from what I can see anyway 🙂

Any ideas/tips on improvement

I presume this is your StarStaX version? There really is no point using Photoshop for stacking star trails, as it takes so long. StarStaX is really quick.

As regards tips, it looks like your camera moved very slightly about half way through your exposures. Make sure the camera is well secured on a tripod and can't be moved, otherwise, you'll end up with wobbly trails!

You need to think about adding foreground objects to add interest to the image. The telegraph pole doesn't do it for me 😉 (and, obviously, my version from last night with a nicely placed water warning sign is not to be taken as a recommendation... it was purely for demonstration purposes!).

I can't seem to see the image at all anymore... is this just me?

Sorry - couldn't get that one to embed (probably me being a muppet). Have uploaded to Flickr instead:

StarTrails_2 by Christina Chester, on Flickr

..And hopefully that should do it…

As regards tips, it looks like your camera moved very slightly about half way through your exposures. Make sure the camera is well secured on a tripod and can’t be moved, otherwise, you’ll end up with wobbly trails!

Thanks for your speedy feedback Mike! Much appreciated. Major problem with the wobble as I can't get my remote shutter release to work with my camera so I have to gently press the button… A right pain! Thinking of taping it down. Do you think that'll suffice as an alternative solution?

You need to think about adding foreground objects to add interest to the image. The telegraph pole doesn’t do it for me  (and, obviously, my version from last night with a nicely placed water warning sign is not to be taken as a recommendation… it was purely for demonstration purposes!).

Hahaha! But I like telegraph poles… especially when you want to observe something and they're right there, in your line of sight… 😉

Yes, I absolutely agree!!! The street lights turn off at midnight so I went and sat in the road (I thankfully live on a quiet road) so that I could get the north star in shot. Will have to scout out a better location. Just wanted to get to grips with the camera settings really. I can see there's quite a bit of noise there. Any tips on reducing that and still getting plenty of stars visible?

Thanks for your speedy feedback Mike! Much appreciated. Major problem with the wobble as I can’t get my remote shutter release to work with my camera so I have to gently press the button… A right pain! Thinking of taping it down. Do you think that’ll suffice as an alternative solution?

What you can do is use a 2 or 10 second delay so your camera stabilises after you press 🙂

I still can't get your image - the link just goes to Flickr (the main site).

How do you embed the image? The easiest thing to do is to click on the 'Share' button on Flickr, then click on BBCode and select one of the medium links.
Hope this helps!

Thanks 🙂 I was trying to embed using the HTML. FAIL. I've updated the above post.

What you can do is use a 2 or 10 second delay so your camera stabilises after you press

Not an option on my camera I'm afraid - Adding new camera to my ever growing shopping list. Nice work around though!

Not an option on my camera I’m afraid – Adding new camera to my ever growing shopping list. Nice work around though!

You do not have the option of a delay on your camera? I would have thought all cameras have that option?

I can see the image now! Good work for a first image of star trails and as a trial run until you find your foreground object 🙂 but I can now see what Mike means about the telegraph post! Mind, if there had been lined up birds on the cable, it would have been fab!

What camera do you have, out of interest? Is a Triggertrap an option?

I can see there’s quite a bit of noise there. Any tips on reducing that and still getting plenty of stars visible?

I can't see your EXIF details on the image, so it's difficult to say, but it's usually a case of lowering the ISO to get the best compromise out of exposure time and sensitivity. To be honest, the amount of noise in the image isn't bad.