Saturn 8th April

[Rob_Jn]

My first Saturn this year, waited until Saturn was near the meridian and took 3 series of AVI's, seeing average. This series was about the best using a 5x Powermate = f29. The blue channel was very blurry and let's it down a liitle. Nevertheless I'm pleased with the result.

Can't be seen on this image but Dione was very close to the limb and a few minutes later went into occultation.

Rob.

[The Bat]

Lovely pic! Well done.

Rachel

[AztecastroMcJ]

Very nice result there

cheers

James

[Rob_Jn]

Thanks Guys!

Hope to get better seeing next time.

[neil phillips]

Nice image what scope are you using

[Rob_Jn]

Nice image what scope are you using

Hi Neil, I'm using a 14" f5.2 reflector. Not ideal for planetary but with good seeing can get some reasonable results.

Thanks,

Rob.

[oldfruit]

Great result, even with not so good seeing conditions.

[Space Cowboy]

Very impressive image!

[Glasspusher]

I have seen many fine planetary images taken with fast-ish newtonians, this is another one, seems like the old myth about such scopes not being good for planetary imaging needs to be revised!!!

John

[brianb]

Very nice image!

seems like the old myth about such scopes not being good for planetary imaging needs to be revised!!!

Yeah, like a lot of old myths ... nevertheless a 14" f/10 would probably work better ... as would a 16" f/4.8.

[Kokatha man]

A very nice image Rob....!

As to newts and planetary, I'm switching from an f10 Celestron C11 SCT to an f4 16" newt.....I think I'll benefit noticeably, and there are quite a number of other experienced imagers that have or are making that sort of transition.....

The shorter OTA (and often lighter weight) of these "faster" f-ratios is one factor for a lot of us planetary folks.....and I don't think the image scales that were a (major) factor in this old "myth" are quite as important per se.....most planetary imaging involves barlowing the image, and aperture still rules therein.....

14" of aperture is really the "fine & dandy" aspect of your imaging rig to me Rob, regardless of type of scope or f-ratio!

[Clayton]

Nice image Rob

[astroman001]

Rob,

Nice image.

Peter

[Rob_Jn]

Thanks for the comments everyone.

A very nice image Rob....!

As to newts and planetary, I'm switching from an f10 Celestron C11 SCT to an f4 16" newt.....I think I'll benefit noticeably, and there are quite a number of other experienced imagers that have or are making that sort of transition.....

The shorter OTA (and often lighter weight) of these "faster" f-ratios is one factor for a lot of us planetary folks.....and I don't think the image scales that were a (major) factor in this old "myth" are quite as important per se.....most planetary imaging involves barlowing the image, and aperture still rules therein.....

14" of aperture is really the "fine & dandy" aspect of your imaging rig to me Rob, regardless of type of scope or f-ratio!

I like the sound of your 16" f4 .

I think with Newtonians you really need everything as good as you can for planetary, collimation and mirror cooling a priority. I fitted mirror fans about 18 months ago after some experiments and they do make a significant difference especially when the air temp is falling quickly as in spring and autumn.

The main disadvantage for Newts are the diffraction spikes, at least theoretically, it would be interesting to see a comparison to see if there really is any difference.

Rob.

[Kokatha man]

Hi Rob - I already run a highly modded SCT and collimation and mirror temp are my main priorities there also.....I have primary mirror temp sensors and peltier cooling: and SCT's do have fairly large secondary obstructions as well...

I'm out in the wind at the moment and there's no doubt the stubby barrell of my C11 ("Keg") handles windy conditions better than a huge OTA (although the dew shield acts like a spinnaker and can't be utilised in breezy situations, but fogging of the corrector isn't as likely then anyway...)

That's why the VX16 appealed in other ways as a fast newt - under 160cm means it won't be nearly as vulnerable to wind (very bad here at home) as the much more massive unit I had started building before I decided the OO was a far better option.....I know that there'll be issues with the newt that are somewhat different to the SCT but I'm nothing if not game to try..!:)

I'm putting together 2 versions of mirror cooling for the VX (I don't believe fans by themselves are adequate here in Oz for mirror cooling).....normally I do a lot of imaging out in the bush where we go in our caravan, and I often run the car on idle (it runs on LPG) and have heavy-duty cabling driving the C11's peltiers to cool the primary: I've made a device (using velcro) that attaches to one air conditioner vent (I'll switch all other vents off) and the flexible hose will vent the cold air from the air conditioner into the back of the primary for the VX (obviously haven't made that end till the scope arrives...)

The other is "Blizzo" which is essentially a small portable air conny that does the job the auto unit does but running off one of those little invertor gennies which I use to charge the vans quite large battery bank.....and I'm thinking of having a timer stepping the thermostat of Blizzo so that I can make the cooling a little more "controlled":D

My little slightly insane inventing mania helps pass the time between poor seeing spells - but quite a few (like all the C11 mods) have certainly assisted in optimising performance.....