Mak 127 - figuring out the 'sweet spot' EP focal length on the planets

[BGazing]

I've settled a while ago on Baader Zoom Mark III and use it in combo with ES 24mm 68 deg for wider field (as the 24mm on the zoom is straw-like). Other eyepieces rarely get out of the box, except when I am doing outreach...

Last night I had a pretty good seeing which I would rate as Pickering 7 easily, but the sky was not that dark, it was 19.87 on SQM-L and there was a bit of moisture (which near the city inevitably pushes the number lower than desired). Now, on all three planets I have observed - Jupiter, Mars and Saturn, the viewing was very steady, and the views crystal clear on 12mm, which is about 1mm exit pupil and around 125X magnification, give or take something since I have upgraded my stock diagonal. Whenever I pushed it to 8mm (to get some use of it) the view got (understandably) bigger, but also lost sharpness. I understand that this is how it works as the eye needs both the size and the brightness to resolve things, but I was under the impression that 8mm on a good night would not be pushing it too far on 127 Mak. After all, it is around 187x. Am I missing something, is 8mm usable on 127 Mak at all?

I feel like 10mm would be better, but then again the stock 10mm is not good at all. Can the Hyperion zoom be used between the clickstops effectively? I.e. is it a continuous zoom, with stops being for one's information, or are the clickstops rather the only option when changing the focal length. I tried and it looks to me like the former is the case, but I just want to check if anyone else has the same experience...or I might be hallucinating.

 

[orion25]

Hi, BGazing

I don't have any experience with the Hyperion zoom, but I do have a 127mm Mak (Orion) and I enjoy pleasing close-up views of the planets with my Orion Expanse 9mm EP. The AFOV is 66 degrees and I estimate the eye relief to be around 15mm. I love the Expanse series because of the nice eye relief, field of view and relatively low cost. I have an Expanse 6mm as well but the view is, of course, more diffuse. For me, 9mm is my realistic limit for the planets.

[YKSE]

The click stops are just for information, you can use anything between the stops, that's the beauty of a zoom

8mm in your f12 mak gives 0.68mm exit pupil (8/12), it will need quite good seeing to be useful. besides, you're probably start to see floaters in your eye, which would make it more difficult to see clearly.

[CraigT82]

Yes you can you the zoom in between clicks no worries. 

It may be that the seeing wasn't actually that good, just looks quite good at lower mags... Keep trying the 8mm setting and you'll soon get a good night where it will be nice and sharp 

[BGazing]

8 minutes ago, CraigT82 said:

Yes you can you the zoom in between clicks no worries. 

It may be that the seeing wasn't actually that good, just looks quite good at lower mags... Keep trying the 8mm setting and you'll soon get a good night where it will be nice and sharp 

thank you all, guys! it looked like somewhat lower than 12 was the sweet spot. also, i can use the zoom as a sort of a helical focuser, LOL. beats mirror flop for sure.

craig, the seeing was good, i reckon it was just not that transparent. the image was really, really steady.