messier objects with 90mak

[Ags]

Yes, a 90mm mak should give excellent views of Jupiter and Saturn at 150 to 200x.

[michael.h.f.wilkinson]

You could also get a mini-giro mount, or a Skywatcher AZ4.

[Walky]

Don't give up on your scope! Many people complain about their 90mm Maks because they have it mounted on a cheap camera/video tripod which can't provide the stability that these high magnfiication scopes require. A mount/tripod with a dovetail socket specifically made to support telescopes would be best. Take a look at something like this:

Orion VersaGo II Altazimuth Telescope Mount | Orion Telescopes

It's kinda heavy at 13 lbs., but it's 15 lbs. load capacity will give you the stability this scope needs (and more).

Also, you may find the small 21mm stock finderscope problematic in targeting objects in the sky. May want to get a bigger one (30, 40, or even 50mm).

Regarding Jupiter, even with the supplied low power 32mm eyepiece (39X), I can see a hint of the two cloud bands - but the seeing has to be good and the higher the planet is above the horizon, the better. I noticed that the detail on the planet is not as good at 45 degrees above the horizon than it was a month ago when it was at the zenith (directly overhead).

Good information. This is exactly my case, the camera tripod is not good enough and this looks sturdy. Of course I am aware we are talking about a very basic setup for a beginner. I only expect to see the bands at least; the 32mm, then, should suffice "if high on the horizon" Good info.

[Walky]

Yes, a 90mm mak should give excellent views of Jupiter and Saturn at 150 to 200x.

Sorry to ask... I think I will be doing a lot of it.

How do I get that "150 to 200x"?

F.L. primary lens/ F.L. eyepiece...

Which is the FOCAL LENGTH, the 90mm or the 1250mm? (THIS!, OK) -- i answered myself, couldn't wait....

So, next question would be, thinking of buying a 7-21mm zoom--- That should help, yes or no, what brand, which is quality/price compatible with a cheap MAK 90.

[Walky]

What can I do to have the camera pointed DOWN, so I can see through the camera screen in an upward position? In the current setup, the camera screen points down as I point upwards, so I need to lean and bend under the scope angular direction to be able to even look at the camera settings and change them.

Also answered. I already had a camera adapter, but after buying it I got engaged in taking photos without the EP, I forgot about it. It's on the MAK and I can look DOWN now.

Next stop to make it more enjoyable?

1- Sturdy mount

2- Enhance Magnification

[michael.h.f.wilkinson]

Sorry to ask... I think I will be doing a lot of it.

How do I get that "150 to 200x"?

Using eyepieces of about 8 mm and 6.3mm respectively

[Walky]

Cool stuff.

[Terrynak]

So, next question would be, thinking of buying a 7-21mm zoom--- That should help, yes or no, what brand, which is quality/price compatible with a cheap MAK 90.

Many amateur astronomers avoid a zoom lens, saying the views are not as quality as getting individual eyepieces. Others also complain that the bulkiness of the zoom lens and the resulting obstruction it creates at the back of the scope (especially if a barlow is attached) is problematic and interferes when looking through the finderscope. Just something to think about.

[Walky]

Will be taken under consideration. Thanks so much for the tidbit. I guess I will go for a 6-9mm since I think the 9mm I have is of no good quality.

[Walky]

Congrats on taking on the Messiers with your 90mm Mak. Earlier today I had a Celestron C90 Mak delivered to my door! Hope you've made great progress since starting out last month - has the weather cooperated?

Using a small 100mm F/5 fast Newtonian scope (Orion Skyscanner) and detailed star charts, I was able to detect the more difficult Messiers in an orange zone site with little difficulty (e.g. M74, M76, M109, M108, M33, all 16 Messier Virgo galaxies). In your case, I would think the most difficult Messiers would be the ones more southerly placed (e.g. M83 in Hydra, M55 in Sagittarius). I observe from further south (34°N in Los Angeles), so I have less difficulty in this respect.

Although I don't think I've observed all 110 Messiers, after tackling the most difficult and interesting ones on the list, I've moved on to non-Messier DSO's, mainly galaxies and nebulae. I use the DeepSkyPedia website as my main resource to plan observing sessions - I pick constellations that are in season, sort objects (mainly galaxies) by visual magnitude, and then choose those objects that are within the aperture capabilities of my scope, also taking into account surface brightness of each object (similar to what Double Kick Drum does).

Last night I had two fast scopes out at my urban light-polluted front yard – my 80mm F/5 achromatic refractor and the 100mm F/5 Newtonian I usually use at my orange-zone site. Using the same eyepiece at 32X, I was able to detect M1 with the Newtonian but not with the refractor. However, double stars looked sharper and more cleanly split with the refractor scope. Looking forward to seeing how the 90mm Mak performs on planets, double stars and DSO’s compared to my other two scopes.

Attached is a pic of the Orion Skyscanner - my portable deep sky scope - along with the Adidas backpack it's housed in.

let me interject:

Would it make difference if I add a celestron st 80t-A which is f/5, 400mm F.L. To the current c90 MAK, which is f/13 and 1250mm f.l.. OFf course if I had known more before, know I would have one scope worth ~$500, just one.

[michael.h.f.wilkinson]

Visually, the focal ratio makes little difference, except in terms of maximum field of view. For a given aperture, an F/4 scope with 8 mm EP gives the same view as an F/8 with a 16 mm EP. My F/10 SCT is my main DSO hunting scope. It has bagged me more than 400 so far, so I must be doing something right. Focal ratio is important when imaging DSOs.

[Macavity]

I think these little (and not so little) Skywatcher MAKs are real "gems" tho'.

I'm glad they have now largely rid themselves of the "planetary only" tag. Yes, they *can* have long(er) focal lengths, but the MAK90, MAK102 are still about the same focal length as yer average Dobsonian... Even the MAK127, MAK180, are not outlandishly "slow"... Compared to an SCT. Sure, you ain't going to get 3-4 degree fields (like a fast APO!) but, as DSO hunters (as Michael notes!) Catadiopterics (MAKs, SCTs) are no slouches. Some will tolerate 2" adaptation. If smaller chip (Webcam, Video) imaging is your thing, focal reducers can get to F6... F5...

Dismounting Soapbox now! But I think (say) an F10 "CAT" is not a bad prime mover scope (Imagers add barlows, field reducers to taste). They may be more versatile than sometimes suggested...

[Walky]

What do you mean with "you ain't going to get 3-4 degree fields" How much a degree covers?

And why a " a fast APO!" would do it?

Just need a quick overview to understand the "language"

[michael.h.f.wilkinson]

A fast scope (say F/4 to F/6) has a short focal length, meaning that the image of a larger section of the sky fits in the apparent field of your eyepiece. My 80mm F/6 APO (apochromatic) refractor has about 15.5x magnification with my 31mm Nagler, which means the circle in the sky seen through the scope has a diameqter of 5.3 degrees. To put that into perspective, the full moon covers half a degree, so I can see a circle more than ten times as large in diameter. Any fast scope with 2" focuser could do something similar, it does not have to be an APO.

[Walky]

But will that mean we should want shorter focal ratios, meaning wider views and less mag?

[michael.h.f.wilkinson]

But will that mean we should want shorter focal ratios, meaning wider views and less mag?

That depends on the object. Some DSOs like the North America Nebula or M31 are huge. A low magnification and large FOV are required. Others require much more magnification (like planetary nebulae). It is easy getting a high magnification out of a fast scope, just use a short focal-length EP. You will need a good quality EP, but it can be done. Getting a large FOV out of a slow scope is not that simple.

[Walky]

OK! Now I see. Thanks

[Terrynak]

let me interject:

Would it make difference if I add a celestron st 80t-A which is f/5, 400mm F.L. To the current c90 MAK, which is f/13 and 1250mm f.l.. OFf course if I had known more before, know I would have one scope worth ~$500, just one.

I would first get a proper telescope mount for your C90 Mak (e.g. Orion Versago II or Vixen Portamount). Then you can use the same mount if you decide on getting another scope later, such as the Orion ST80A or Skywatcher 127 Mak.

[Walky]

where do you guys with a C90, mount it? I mean, if you are not planning to upgrade to a better scope what type of mount do you use?

I need it to be light and grab and shoot, goto and tracking capable. A lot to ask.

Not interested in heavy mounts that I would think twice to move or a future possible scope additions.

[4lefts]

it doesn't have goto, but mine is on a skywatcher supatrak mount. it's ok. though a bit wobbly (but a LOT better than a camera tripod). btw - i dunno about the c90, but I would have thought that 200x mag was a bit too much for the scope. my vixen isn't too happy above 150x. have a look at some zoom eps. the baader hyperion 8-24 zoom would be super useful for you, though it's spendy. the views through it are great.

[andrew63]

It's great you have found M1 and after a while you get a bit of an inkling with these patches or smudges. Unfortunately, you will encounter much fainter patches than M1 - but the satisfaction when you've found them is well worth the hunt!

Good luck, andrew

[Walky]

I haven't done much since the last post due to my lack of a steady tripod to place my MAK C90. After much researching and reading I have since acquired a setup for a newly acquired Polarie that will serve as well to support the MAK. It was sliding down from my photographic tripod, since I never used the CG4 (too heavy and cumbersome to take out to a humid, damp and wavy patio). I would rather work with my Manfrotto tripod and ball heads which is a an easier to move setup. If the weather is merciful I will someday post some MAK and wide field photos with Polarie.

[Walky]

Still bad weather. Plagued by stormy weather; several tropical disturbances in my future right now. Have a polarie I canot test drive, new Manfrotto tripod and heads and cannot do a thing.

[nytecam]

Charles Messier frequently used 3.5" apochromatic scopes, of vastly inferior quality compared to what we can get now, in particular concerning transmission losses. I assume the objectives were not air spaced, because just two glass/air surfaces would cause about 10% light loss immediately (no coatings). Six such surfaces would render them useless.

Charles Messier

That's a surprise - Messier using apochromatic scopes in the 1750s - took a long time to reach the current popular market That said your 90mm should show a lot of Messiers if many somewhat underwhelming - good charts are the clue