Imaging with Mak 127mm

[Russe]

From Martin Mobberley's book on webcam imaging:

time window=drift limit / ((nxplanet diameter) / rotation period)

for 0.5 arc-second drift limit for 25 arc second Mars (big Mars)

Mars rotates in 1477 min

0.5/((3.14x25)/1477=9.4 minutes

for 0.5 arc second drift and 15 arc second Mars (small)

0.5/3.14X15)/1477=15.7min

Jupiter:

45 arc second (opposition) and rotation period 590 min

0.5/(3.14x45/590)=2.1 min

Saturn:

45 arc second size and 614 min rotation period

0.5/(3.14x45/614)=4.9 min

However, increasing this value to 6 min will not produce any noticeable smearing on high latitude spots. When there are no spots on the disc or when seeing is not excellent, there is no reason why a 10- or 15- minute run should not be stacked.

Uranus 0.5/((3.14x3.7)/1034)=44.5min

Neptune 0.5/((3.14x2.4)/967)=64.2min - this is a hubble space telescope object though...

Pluto is purely a hubble space telescope object

[Russe]

n in the formula is not the letter "N" but the number Pi (3.14xxxx)

[JamesF]

I wrote a piece explaining the derivation of these timings here:

http://www.tanstaafl.co.uk/2012/03/focal-ratio-capture-length-planetary-imaging/

James

[Yamster]

Hi, I'm new here and to Astrophotograhy

Bought a Skywatcher Mak127 last month wanted to share my image of the moon.

1st attempt was not good from my Nikon D700 then I tried video mode from my Nikon D3100 and here is the result.

Haven't had many clear nights and it looks like it's going to be cloudy here for my 1st full moon

[JamesF]

A nice image
 

Full Moon isn't that exciting from an imaging point of view to be honest.  Because the Moon is illuminated full-on there are few shadows to show up the craters.

James