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jjjnettie
27-04-2012, 11:53 AM
I purchased a Tamron 18-200 f3.5 - 6.3 lens the other week for day time snaps and thought I'd see how well it would work when pointed up at night.
I used the Modded 20d for the capture. (still learning how to process the data) I didn't bother setting up the guiding, as I thought the clouds would be back at any moment. who would have thought it would end up being the best night in months and an all night session. lol

Eta was taken at approx 140mm, ISO 800, F9, 5 x 5 minutes.
Antares Region, same specs, 8 x 5min
And the big wide field taken at 18mm, ISO 800, F5, 8x5min.

Lessons learned
Remove the lens hood when shooting at 18mm.
For the close up shots, F9 is too much. Drop it down to F7 and maybe go up to ISO 1600.
I need to practice processing this type of data more. Colour correction is a right pain to get right.

I'm pretty happy with the results so far. I'll continue working with it, experimenting with aperture and exposure times. If I get a marked improvement, I'll post them on this thread. :)

rogerg
27-04-2012, 12:36 PM
That's a nice zoom range for a general purpose daytime lens!

I look forward to watching your results to see how the lens quality ends up. It doesn't look like there's any problem with these shots! , perhaps slightly soft? but I expect that's the processing choices not the lens considering the image size.

blink138
27-04-2012, 01:37 PM
wow you can really see the shape of our galaxy with the 18mm
pat

multiweb
27-04-2012, 02:42 PM
Very cool field - sharp to the edges. Pretty cool at 18mm :thumbsup:

gregbradley
27-04-2012, 04:02 PM
Some very nice images there JJJ. Modded 20D, nice one, I have one of those.

To save time on processing you should get yourself an 18% photographic grey card and shoot a custom white balance in sunlight and use the photo as the custom white balance.

Colour won't come out perfect but they are reasonable instead of being all red.

Greg.

[1ponders]
27-04-2012, 05:46 PM
Wow, that Rho/Antares shot. great framing

jjjnettie
27-04-2012, 06:13 PM
As for the pics being sharp across the field, I used the Lens Correction filter in CS3. :)
Thanks for looking.

xstream
27-04-2012, 07:25 PM
Just what you needed for Coona, Jeanette.
Nice imaging too btw.

alan meehan
27-04-2012, 08:17 PM
Nice shots jjj looks like a very nice lens ,like Antares great work
AL

Forgey
27-04-2012, 08:34 PM
Very nice jjj, looks like the lens is going to do the job!