Omegon 127 Maksutov

[johninderby]

Omegon 127mm F15 Maksutov

You might call this Bresser Mak part II 😁

Wasn’t intending to replace the Bresser 127 mak sold to help pay for something else but came across the Omegon on offer at Astroshop for £100.00 off the regular price and just couldn’t resist. Like the black OTA. 🙂

The Omegon is a full 127mm aperture, not only 118mm  like the Skymax 127. Also has a bigger primary and a smaller central obstruction. Tube is bigger in diameter than the Skymax to accomidate the bigger primary. Just on simple aperture alone it's 8% bigger but due to the smaller central obtruction it's about 10% bigger in aperture area. A worthwhile difference.The inside of the tube has micro baffles machined into the tube all the way down which helps contrast a bit. The skymax just has a smooth painted surface inside.

Unlike the Bresser it comes with a Synta type finder shoe and no cheapie diagonal or finder. Why waste money on poor quality accessories. Just don't like those visual backs with a screws that bite into the diagonal so replaced with a Baader visual back. Will be using a Baader prism diagonal. Fitted a Skywatcher 6x30 RACI finder on a low profile bracket.

And fitted a WDS aluminium carry handle. 

Sits nicely on my Manfroto 475 geared tripod and Manfroto 405 geared head. The head has beem modded by removing the centre geared secton to make it into an Alt-Az head. I have used a C8 on this combination which was pushing it's capacity to the very limit. Doesn't even notice the weight of the 127 Mak. The whole setup with OTA can easily be carried single handed outside. Proper grab'n'go.  

Edited April 8, 2020 by johninderby

[Sunshine]

That’s a sharp looking and well thought out little Mak, I’m sure you’ll have some fun with that.

keep us posted about first light!

[Louis D]

Can it be fitted with a 2" SCT visual back?

[johninderby]

10 minutes ago, Louis D said:

Can it be fitted with a 2" SCT visual back?

Ues it has a standard SCT thread on the back. 

[Louis D]

1 minute ago, johninderby said:

Ues it has a standard SCT thread on the back. 

Nice, the Synta 127 Maks require a step-up ring to fit SCT accessories.

[johninderby]

Couple of little mods. 🙂

After the sort of first light last night (haze and clouds🙁) found the finder just got in the way of the eyepiece so moved the finder shoe over a bit. Found under the old location there were two sets of mounting holes so filled the threaded holes with grub screws and the plain holes with nuts and bolts. 

Fitted a flanged bearing to the focuser shaft where it passes through the rear dust cover.

And a gratuitous photo of the neighbours cat relaxing on the patio while I worked. 😁

Edited April 9, 2020 by johninderby

[Dave1]

Nice mods.Did you put the bearing around the focuser nob?

[johninderby]

21 minutes ago, Dave1 said:

Nice mods.Did you put the bearing around the focuser nob?

Reamed out the hole for the focuser shaft and press fitted the flanged bearing into the dust cover. The rear dust cover is held on by three bolts so easy to remove when the knob is removed. Underneath is the metal backplate.

[johninderby]

Putting the Omegon 127 mak next to the CC 8” makes you realise how tiny it is. 😁

[Louis D]

As the old US cereal ad might have said to the 127 'If you eat your Wheaties^TM, you'll grow up big and strong like the CC 8"'. 😁

[johninderby]

The Svbony helical focuser arrived. Now have proper fine focusing. 👍🏻👍🏻👍🏻

Monuted on the Baader prism as didn’t want the weight of the diagonal and eyepiece pressing down on the side of the focuser. Focuser is quite smooth.

Edited April 12, 2020 by johninderby

[johninderby]

The mak on an AZ-GTi mount and Manfrotto tripod. Nice light setup that’s easy to carry outside in one piece. The addition of the 1.25” crayford makes a real improvement but is small and lightweight and suits the little 127 mak.👍🏻👍🏻👍🏻

I have the TS counterbalance system that allows using a bigger scope with the AZ-GTi mount but found it’s not needed with the mak. 

 

Edited May 17, 2020 by johninderby

[RT65CB-SWL]

Very nice @johninderby. 

[Louis D]

On 12/04/2020 at 08:53, johninderby said:

The Svbony helical focuser arrived. Now have proper fine focusing. 👍🏻👍🏻👍🏻

Monuted on the Baader prism as didn’t want the weight of the diagonal and eyepiece pressing down on the side of the focuser. Focuser is quite smooth.

 

23 hours ago, johninderby said:

The addition of the 1.25” crayford makes a real improvement but is small and lightweight and suits the little 127 mak.👍🏻👍🏻

So, did you ditch Svbony helical focuser in favor of the Crayford focuser over the last month?  Was the helical focuser not to your liking?  How much does either extend your focal length?

I've found the Orion/Celestron/Bresser 127 Mak focuser to be fine enough for me, and pretty much backlash free, that I've never felt a desire to add a Crayford focuser to either of the two versions I've used.

I tried a 1.25" to 2" helical focuser on my Dob 20 years ago and never took a liking to it.  Much too slow to see when the image popped into best focus.  It needed a more aggressive thread pitch.

[johninderby]

The stock fouser is not bad but find a fine focuser helps. The Svbony helical focuser was OK but had a limited range and when the chance to get hold of the crayford.came up jumped at it. 40mm travel and the fine focus was far better than the helical Svbony. and the regular focus was a lot faster than stock.