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01-24-2019, 01:10 PM - 1 Like   #31
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Photolady,

Maybe I'm wrong, but 300mm on APS-C sensor (1.5 to 1 for 35mm) would be 450mm equivalent and a 2x teleconverter would make it 900mm. That came from my comment where I used a 300mm f4 with 2x converter on a K3. Most of my issues came in more than one axis direction, not just forward motion blurring due to lunar advance. It was 28 F and I was in a hoodie with no gloves. Totally ill-prepared, forgetful (64 years old) and not as good of an equipment check as should have done. Took into consideration that f5.6 with 2x would be F11.2, f6.3 = 12.6, etc. I just screwed up. Usually when I use 300mm, 400mm, 500mm, etc with a 2x for the moon my shutter speeds are 150 - 500 and all is well even if I forget the SR is on, but here I was nailed by SR and lunar advancement velocity. Glad no lives depended on my operational prep for this one!!!

JB

01-24-2019, 06:57 PM - 1 Like   #32
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QuoteOriginally posted by Take-5-JB Quote
Photolady,

Maybe I'm wrong, but 300mm on APS-C sensor (1.5 to 1 for 35mm) would be 450mm equivalent and a 2x teleconverter would make it 900mm. That came from my comment where I used a 300mm f4 with 2x converter on a K3. Most of my issues came in more than one axis direction, not just forward motion blurring due to lunar advance. It was 28 F and I was in a hoodie with no gloves. Totally ill-prepared, forgetful (64 years old) and not as good of an equipment check as should have done. Took into consideration that f5.6 with 2x would be F11.2, f6.3 = 12.6, etc. I just screwed up. Usually when I use 300mm, 400mm, 500mm, etc with a 2x for the moon my shutter speeds are 150 - 500 and all is well even if I forget the SR is on, but here I was nailed by SR and lunar advancement velocity. Glad no lives depended on my operational prep for this one!!!

JB
300mm x 2 equals 600mm, not 900mm, the equivalent of 1.5 would give 900mm.
01-25-2019, 09:53 AM - 1 Like   #33
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QuoteOriginally posted by clackers Quote
Your shutter speed was way too slow.

The moon is much faster across the sky than the stars (20 seconds would be fine for them).
??The moon moves almost the same rate as the stars??
01-25-2019, 10:57 AM - 1 Like   #34
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QuoteOriginally posted by Bob 256 Quote
??The moon moves almost the same rate as the stars??
Yes, it's about 4 percent *slower* as MossyRocks and orhers pointed out to me, Bob.


Last edited by clackers; 01-25-2019 at 12:44 PM.
01-25-2019, 11:40 AM   #35
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QuoteOriginally posted by clackers Quote
Yes, it's about 4 percent *slower* as MossyRocks pointed out to me, Bob.
Why Do Objects Appear to Move Across the Sky at Night? | Sciencing

Seems a good explanation.
01-25-2019, 05:39 PM - 1 Like   #36
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QuoteOriginally posted by clackers Quote
Yes, it's about 4 percent *slower* as MossyRocks and orhers pointed out to me, Bob.
Oops - Sorry about that Clackers. I clicked on the thread and think I jumped in at a point earlier on - quite a few posts had been made that I didn't see. Didn't mean to add to those.

I know you can get hit over the head too many times and then start to see stars
01-26-2019, 12:00 AM - 1 Like   #37
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QuoteOriginally posted by Bob 256 Quote
Oops - Sorry about that Clackers. I clicked on the thread and think I jumped in at a point earlier on - quite a few posts had been made that I didn't see. Didn't mean to add to those.

I know you can get hit over the head too many times and then start to see stars
I'm grateful to everyone to be set right, and glad the thread (which can be googled in the future) contains rich, accurate info.

01-26-2019, 11:47 AM   #38
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QuoteOriginally posted by clackers Quote
I'm grateful to everyone to be set right, and glad the thread (which can be googled in the future) contains rich, accurate info.
I am as well, Clackers.

Plus, I love starting threads that stir the pot a bit. It's the lawyer in me.

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