Ok after my
mediocre efforts of capturing the full moon with the 350D and standard 75-300mm lens, I had to try something different to give myself a better chance of capturing better quality results on lunar eclipse night.
I went back to basics
12" newt on
dob base with 32mm GSO plossl eyepiece, and hand-holding the Canon 350D with lens, pointing into the eyepiece .. The old trusty afocal method - exactly how I started in astrophotography 2 years ago
* The first attachment is with the 17-70mm Sigma lens @ 17mm, f/5.6, 1/500s exposure @ ISO100.
The results were quite good, but inconsistent. The large opening on the 17-70 and the small eye lens of the 32mm plossl meant I couldn't get in quite as close as I would've liked and the moon only took up about 1/2 of the frame (in the vertical direction). I also got a lot of vignetting and it was difficult to get a shot that was evenly illuminated without an artificial umbral eclipse in the form of vignetting
* The second attachment is with the 28mm f/2.8 Canon lens @ 28mm, f/4, 1/400s @ ISO200.
The results were much more consistent here. The 28mm lens is tiny and the opening is very close to the front of the lens, so I could put the lens pretty much right on top of the plossl eyepiece. The moon took up 90% of the frame (in the vertical direction) giving me the resolution I was after. Also, there was no vignetting.
The only problem with this shot, is the moon is blurry on the right edge of the moon. I think it's a result of the cheap GSO plossl and the moon drifting to the edge of the FOV, where the image starts to get blurry (and stars would go seagull!).
If I used a better 30-ish-mm eyepiece, and ensured the moon stayed near the centre when taking the shot, I expect it would be sharper across the field.
I could've used the 12" newt on the EQ6 to keep the moon centered, but chose not to because:
a) The moon is so far South at the moment it's behind a tree from where I set up the EQ mount
b) When I go travelling for the eclipse, I'll take the dob base not the EQ mount, so it was better practise.
The results would also be better if I had an adapter or used a tripod to hold the camera and point it into the eyepiece, rather than hand-holding. At short exposure times (1/500s or so) it should eliminate most chance of hand-shake blurring the image, but there's still a chance. I'll look into getting an adapter in the next 4 weeks
Both images had identical post-processing:
1) Crop
2) Levels/curves
3) Sharpen
4) Reduce to 900px wide for web.
Obviously the 28mm image needed little cropping because the moon all but filled the frame.
The image on the left (from the Sigma) actually looks more 3D and in some ways more pleasing. Not sure if it's due to the colour or the fact it's sharper across the frame. Perhaps the right image is a tad overprocessed. I'll play a bit more in the processing to achieve the best result.
Thanks for looking.