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Mak with TV Plossls

Stu

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Stu

Stu

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After literally years playing around with different eyepieces in my Mak (Orion Optics OMC200), I finally seem to have found a good combination. I used to try and maximise the field of view by using wide field eps, including 2" ones which I bought for my refractors, but this now seems like trying to use the wrong tool for the wrong job!

The OMC200 is a lunar/planetary specialist scope, which is also pretty good on globs and other small DSO's. I've decided to go with the flow, accept the small field of view for what it is, and just to use simple TV Plossls to give best light transmission and minimal scatter. It's an f20 scope so not terribly demanding!

So, I've now got the 32, 25, 20 and 15mm pretty much dedicated to this scope. They give x125, x160, x200 and x267 respectively which should cover most eventualities. For more crazy mags I've got a 12.5mm Hutech and the 11mm TV Plossl normally used in my PST which would take me to x364.

The field of view is never more than 0.5 degrees, but that's not the point of the scope! I have it mounted on a Vixen Sphinx mount and that does make finding things far easier, although it needs to be set up pretty well to plonk objects straight in the very small fov. An accurately aligned finder is essential!

Anyway, just been out using these for the first time properly, and am very pleased. The double double split very nicely at x125, and Izar was also a nice clean split. The star shapes are never going to be refractor like, but they were as good as I can recall seeing in this scope.

I finally plucked up the courage to dismantle the Sphinx and adjust both axes as they were rather stiff which made finding a good balance on the scope tricky. That's now sorted, and the other advantage of the Plossls is that there is limited variation in weight so changing ep doesn't really affect the balance at all.

All in all pretty happy now, popping back outside to do battle with the mosquitoes and hopefully see a few more things before bed.

Enjoy if you are out there.

Stu

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Mark at Beaufort

Mark at Beaufort

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Stu I have only had my 180 Mak 2 months but I have been very pleased with views of the planets and the Moon. Last night I went in the opposite direction to your EP selection and used my Ethos EPs. I am going through the Lunar 100 and I needed to bag a few more objects.

I have to say that the view through the 13mm and 8mm was fabulous and I could easily view the objects that I wanted to see. The 180 Mak is supported on an original SkyTee alt/az mount so therefore all movement is done by pushing so the 100 degree FOV is very useful.

I have never viewed through a TV plossl but did think about buying a pair to use with the binoviewers.

After viewing the Moon last night I did switch to viewing Saturn with the binoviewers using some 12.5mm William Optics Planetary and that was pretty nice.

Perhaps if a TV plossl comes up on the S/H market I should grab it quick.

Mark

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Moonshane

Moonshane

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I am a TV plossl fan also. despite having some wide field TVs I find the plossl are just as sharp as anything else I have and provide very satisfying views. the 11mm seems to hit a sweet spot in any scope I use it in although the eye relief feels a little tight even compared with my 7mm BGO. I have a 32mm, 25mm, 20mm, 15mm and 11mm myself. Stu, did you do any more tweaking of the collimation of the big mak? the methods of the 'experts' at PSP did seem somewhat hit and miss to me. my effort was no better but I consider myself totally lacking in Mak collimation knowledge! (other than common sense).

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Stu

Stu

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I am a TV plossl fan also. despite having some wide field TVs I find the plossl are just as sharp as anything else I have and provide very satisfying views. the 11mm seems to hit a sweet spot in any scope I use it in although the eye relief feels a little tight even compared with my 7mm BGO. I have a 32mm, 25mm, 20mm, 15mm and 11mm myself. Stu, did you do any more tweaking of the collimation of the big mak? the methods of the 'experts' at PSP did seem somewhat hit and miss to me. my effort was no better but I consider myself totally lacking in Mak collimation knowledge! (other than common sense).

I'm certainly enjoying using them. Strangely I only seem to use the 11mm in my PST where is is just about perfect but should give it a try in the other scopes. It would give a rather lovely x320 in the mak which could be spectacular on the right night.

I haven't done anything much with the mak Shane, but am getting braver in what I am prepared to do with it. I took the front corrector off last night to clean it and will probably try the same with the mirror cell this weekend. The collimation doesn't seem too bad, but I know there is something not right and that I'm not using the full mirror aperture. Looking through a Cheshire shows it is not all visible. I don't think this can be fixed by simply adjusting the secondary so will look at how the primary is mounted to see what adjustment there is.

The star test is odd in that the diffraction rings are disrupted in one sector so need to investigate that too.

That said, double double looked nicely split last night so imagine what it will be like when working well!!

Stu

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dave armeson

dave armeson

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Myself being a VERY HAPPY MAK 180 owner, went and got a full set of TV Plossls want "The Best" for my scope. They were excellent, however after having a night with Martin Dawson of York AS up at our observatory who has an outragous eyepiece collection I was absolutely in awe, when he put in an on 1980's orthoscopic eyepiece, the sharpness across the whole field was a revelation. I ended up selling my TV plossls and sourcing a 20mm, 18mm, 12.5mm and 9mm ortho. The Mak has never been better. FOV isn't everything when using a Mak...!

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dave armeson

dave armeson

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Myself being a VERY HAPPY MAK 180 owner, went and got a full set of TV Plossls want "The Best" for my scope. They were excellent, however after having a night with Martin Dawson of York AS up at our observatory who has an outragous eyepiece collection I was absolutely in awe, when he put in an on 1980's orthoscopic eyepiece, the sharpness across the whole field was a revelation. I ended up selling my TV plossls and sourcing a 20mm, 18mm, 12.5mm and 9mm ortho. The Mak has never been better. FOV isn't everything when using a Mak...!

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Stu

Stu

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Trouble with my scope is that the focal length is pretty much 50% longer than the 180 Pro at 4000mm. I have a set of BGO/Hutech orthos and the 18mm is very good in it, I was after some longer focal lengths as the 9mm for instance gives x444 which is rarely useable.

When the skies get darker earlier, I will spend some decent time comparing the orthos and Plossls to see what I find. I guess the 25mm Hutech would be worth a look if there is an appreciable difference in sharpness.

One other question is whether the 80's orthos were better quality than those produced now? I suspect they may have been.

Cheers,

Stu

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