Hi Paul,
Quote:
Originally Posted by Sentinel
I could not see Ton 2. It's eluded me for years. One of those Hartung objects that bugs me.
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I'm not for a moment pretending that Ton 2 is easy -- it isn't. There is a certain knack to seeing so many of the difficult non-NGC GCs. Actually it's not so much a knack as a "paradigm" -- I think the keys to success are:
1st rule: Don't look for a GC. The traditional mental pic of a GC is a hindrance. Pretend you are looking for a small late type (ie Sc or Sd) face on spiral eg. No stars, no central condensation just a round smudge of weak gossamer.
2nd rule: (and this would appear particularly applicable to you
) -- slow down. Be patient. You will probably need a several minutes at the ep before detection.
3nd rule: use some magnification -- use an eyepiece that approximately gives a 2mm exit pupil for best contrast on small LSB objects
I have seen it in my old 25cm under a mag 6.4 sky with eyes that were more than a decade younger -- very, very difficult though in that size. It is a little easier in 31cm. Once you've seen it once it's easier the next time.
25cm obs: x181 17' TF. Mag 12.24 Size 25.8" This cluster is found 7-7.5' to the NW of mag 4.5 Q Scorpii. This must be excluded to permit detection. Extremely !! faint in this apeture, barely there but largish, 2.5' -3' diameter as a weak patch of diaphanous gossamer with no central brightening. Mag 13 * superimposed in the WSW near the edge. Round. Confirmed by G Mitchell.
46cm: x247 20' TF can be held steadily with averted vision though it is hardly bigger, has an even surface brightness halo and shows no sign of resolution.
Find mag 4.3 q Scorpii in the tail of the Scorpion. 10' WNW of this star is an 8th mag star. Pick the mid-point between these two and it is just a few ac-mins north of the mid-point.
Try, try, try again!
Best
Les D