10 x 3 minute images at F10 2500mm FL with modded Canon 350D taken from my house Brisbane.
It looks like I will be imaging at F10 for a little while now until I can purchase a decent focal reducer.
Hutech light polution LPR filter used.
Would have liked to have got more images and longer exposures....tracking was acceptable....you can see some slightly oblong shapped stars but I am not after perfection...well yes I am but I am not going to say that...lol
Pretty happy with this one for just a quick target...will probably post another M20 later on with more data..hope you dont mind.
Thanks Andrew and houghy(I think)...I havn't learnt the masking method..looks simple but I keep getting it wrong.
I may have to settle for large scale F10 imaging...it's not all bad
I just never wanted to image at that focal length because it was too hard...F6.3 1700mm is much easier but now the mounts performing much better what the hell...lets do it.
In theory, nebula filters like the UHCS are more efficient at F10 as the cone of light is more parallel, and as the filter is an interference based filter, the passband will be more accurate, at very fast f ratios the light hits them at more of an angle, meaning they arent as efficient. Grab the UHCS filter and tilt it while looking through it in daytime, you will see the colour change.
Anyway your tracking is certainly handling F10 well. If you go 4 times longer (or 4 times as many subimages) you will still get same brightness as shooting normally at F5. E.g. shooting F5 for total of 15 mins, can shoot for 1 hour at F10 and get same intensity (but better images due to better filter efficiency)
Scott
I am intersted on how the hutech LPR filter will perform now..I think I will get a much more natural colour now instead of over doing the red bias....we will see.
Hi Tony took the liberty of running your image with Richarson Lucy enhancement with ImagesPlus. This would work much better with the original Tiff.
Here are two crops. Which is which?