Different galaxies - different magnification

Galaxies come in many different shapes and sizes. Experts: To get most of the elusive detail, which magnifications would you use on the following galaxies using a mid-size Newtonian (10 - 14")?

M31
M33
M101
M51
M81
M82
NGC4565
M100
M99
NGC1023
NGC7331

????

using a mid-size Newtonian ... or a small refractor?

Dmitri

As long as the detail means fine detail I would probably use eyepieces yielding exit pupils of 1.5 to 2.0 millimeters on all of the objects.

Dave Mitsky

A friend of mine referred from a star party in Germany that the experienced guys played around with different eyepieces for different galaxies. He told me that just changing from a 13mm to a 17mm eyepiece made a lot of difference, and in some cases the 13mm was best, in other cases the 17mm.

My set of eyepieces is small right now, and I have a gap between 63x and 167x magnification(exit pupil 5mm and 1.9 respectively). For M33 63x is too little, but 167x is definitely too much. For M82, on the other hand, 167x seems to be a very good choice. For M51 I suspect that a magnification in the 120 - 140x range would give the best views.

I had a very strange experience with NGC891 last autumn. I wanted to check it with my 9mm Nagler (167x), but put in the 4mm Radian (375x) by mistake. To my surprise the equatorial dust band beautifully appeared - in fact it was better at the high magnification than with the 9mm.

Inge S

I see the most detail when the exit pupil is around 1.5mm. I believe that more detail is visible with exit pupils as low as 1mm, however seeing rarely permits the higher magnification with my scopes. When seeing permits, the smaller exit pupil is usually better. That translates to magnifications approximately 150X - 250X for the 10" and approximately 225X - 350X for the 14". The 7mm Nagler T6 is by far my most used eyepiece (285X in 17.5" f/4.5). M82 is stunning at 285X, but loses a lot of detail at lower magnification. The proof is in the results. Using 1-1.5mm exit pupils with the 17-1/2" has allowed me to observe almost 400 galaxies in the Coma Cluster and over 300 galaxies in the Perseus Cluster.

Bottom line, experiment with a wide variety of eyepieces. Use magnifications higher than observing lore suggests.