Schiller--exercise in image scale

Hi all,

Beenplaying with some older images using Reg 3 (finally getting the feel for that one). I'm posting the mosaic that I shot at 11500mm fl using a 5X's powermate, its redone in Reg 3 (old one was ver 2) and processed a bit harder. I also did another avi very soon after with a 3X's televue barlow so that would about 7500mm fl. Seeing was pretty much the same for both avis and I tried to process both the same using wavelets in Images Plus, I think that when the seeing warrents it then its very worthwhile to shoot at large image scales. My shot done with the 5X's barlow shows many more smaller features like craterlets in the floor of Schiller. Sure shooting at long fl's has its probelms like less light, tracking problems etc but I think if Mother natures co-operating then go for it!!
What do you think?

cheers

Mike W

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Heres the 3X's barlow version

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Hi Mike -

Nice comparison. I think when when imaging the moon with a large scope increasing the effective focal length will produce a higher resolution image. You will probably always reach a limit defined by the seeing before you are limited by aperture. Prettier pictures might be made at a shorter focal length - but the higher magnification view will reveal finer features.

Seems things are a little more complicated on the planets and their low contrast details. Here there may be a sweet spot at a shorter focal length than would be optimum for the moon. It may be my inexperience with very fine seeing conditions, but I seem to get as good or better results from my 10" mak at f28-30 than f40-45.

Alan

Hi Mike,

Great! images, I never go below a 4x barlow and most of the time I use a 5x barlow, with our 18" scopes though a focal length of 11500mm is just starting to get the motor reved up

Thanks,

Wes Higgins

Oh very nice Mike. Super!

Jim Phillips

Hello Mike,


Awesome!


Kirk

Just curious - what would you guess is the diameter of the prominent craterlet in the left-side floor of Schiller? I'm trying to get an idea of the resolution and distances I'm looking at.

These days, looking at the awesome lunar and planetary images that are often posted here by you and the usual cast of characters is what I look forward to most. Please keep them coming!

Doug

Hi Mike,

Great looking images with a tremendous amount of detail. I imaged Schiller about 6 or 7 weeks ago at a focal length of about 5000mm with my 8" SCT. You said the prominent crater on the floor of Schiller is 3 kilometers in diameter and that is in my image. Do you have any idea what the smallest feature I can expect to image on the Lunar surface with an 8" scope?

Thanks,

Ed Roach

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