107 replies to this topic

[jmccown]

Review of  Celestron - PowerSeeker 70AZ 70mm Refractor Telescope

I have been in a long hiatus from observing. Gave my 8” Coulter Dobsonian to my nephews a long time ago. Also formerly had a Meade 6” f/8 Newtonian and a department store 60 mm refractor.

I know many of you will scorn my choice of scope, but I don’t have a lot of money. (Yes, I have binoculars). I decided to risk $70 and order a Celestron PowerSeeker 70AZ 70 mm, f/10 refractor. I know you get what you pay for, but for $70 there’s not much to lose either. And since Celestron has a good rep, I decided to give it a chance. (I actually got some acceptable use out of that 60 mm department store refractor I had long ago.)

The Celestron arrived with 20 mm and 4 mm eyepieces, and a 3X barlow. When I assembled it in the house, the OTA and mount appeared to be of solid construction. I still haven’t figured out how to adjust the finder scope.

 

First Night:

I found it very difficult to use the finder scope. It’s mounted just to the left of the focuser, intended for use with your right eye. Unfortunately, my left eye is my dominant eye. It gave me the same problem many guns have given me. I shoot rifles and shotguns left-handed due to my dominant left eye, but most of them are made to be shot right-handed. I need to figure out some way to mount it on the right side of the scope.

I looked at a few bright objects that first night: the moon, Venus, Jupiter, and M42. The views with the 20 mm eyepiece were decent. The 4 mm was close to worthless. And the 3X barlow was completely worthless. I was unable to focus the scope with the 20 mm eyepiece stacked on top of the barlow. I think the barlow may be defective. It will not focus at any position the focuser can reach.

I got decent views of the moon with both the 20 mm and 4 mm eyepieces. But getting the scope pointed in the right direction was very difficult, due to the problems with the finder. I could not get very good views of the gibbous Venus with either eyepiece. Between the glare from that bright planet and the small apparent diameter (about 14 seconds), I was unable to resolve the disc satisfactorily.

Jupiter was much better. I got a decent view of it with the 20mm eyepiece. I could see all four of the moons clearly and also the two belts near the equator. Between the high altitude of the planet and the difficulties with the finder scope, I was unable to get the planet in view with the 4mm.

M42 looked very nice in the 20mm eyepiece.

I do not understand why they included a 4mm eyepiece with this scope. 175X is well beyond the useful magnification of the instrument. I think 100X may be the practical limit. Celestron offers an accessory kit that has 15mm and 9mm eyepieces. I think I will order that next.

 

Considering the price, the quality of the optics and stability of the mount were decent. I didn’t see any excessive color problems.  But there was a bit of stray light.

 

Second Night:

I turned around the mount for the finder scope, so now I can look through it without banging my ear against the focuser. I still have not figured out how to adjust the finder. And when I tried to use it on Jupiter which was near the zenith at the time, it was very difficult to look through the finder. I had to sit on the ground whilst craning my neck up to the finder.

Had a nice view of the crescent moon with the 20mm eyepiece. Venus was the same problem as the previous night. Between the bright glare of the planet and the small apparent diameter, I was not able to resolve the gibbous disc. I need some more eyepieces and a filter or two.

Once I was able to point the scope at Jupiter, I got good views. I even tried the 4mm eyepiece and got reasonably decent views of the cloud belts. I think a 6mm or 7mm would be better.

M42 looked very nice again. I wanted to have a look at M81 and M82, but it began getting very hazy, and had to quit for the night.

For any scope and mount, you have to learn their idiosyncrasies in order to use them well. Plus the fact I haven’t observed in decades. I am slowly learning with this scope. And I must say I have been pleasantly surprised so far.

I shall make follow-on posts as I make further use of the scope.

[Patricko]

Great report! I'm glad to hear you are getting back into the hobby. You can be surprised how far a small refractor will take you with experience and dark skies. 

[AndresEsteban]

It's good to hear you're back!!! Regarding the 70mm f/10 Celestron, these are not bad refractors at all, they have a good objective but poor eyepieces! You´ll need to buy some decent eyepieces. Unfortunately you'll spend more money in these eyepieces than the one spent on the telescope. But that's teh way it is. May I suggest some eyepieces?
Plössl or orthoscopic eyepiece: 10 & 6 or 5mm
Wide angle eyepieces: 15 and 20mm
I don't like barlows with this small aperture refractors. I have a vintage 76.2mm f/16 refractor and never used a barlow. I prefer a good eyepiece to reach the proper magnification.

With 70mm you'll be able to reach easily 180x on good seeing conditions (2.5 x objective diameter in millimeter), which is a good power for the moon and planets!. I easily push my 76.2mm f/16 up to 210x on planets (Jupiter, Mars, Saturn) and the Moon, not bad considering this is 70x per inch!
Clear skies!
 

[Don Taylor]

2nd the suggestion to get better eyepieces - a good low cost line are the Value Line Plossls from our sponsor Astronomics.  just over $20 each for the medium and shorter FL's.  They are surprisingly good  (they're actually the same as the GSO Plossls I believe). Be aware that eye relief gets very short with short FL Plossls - The 9mm FL one is as short as I can use ( and I don't wear glasses when observing)

 

Glad you are back with us!

Edited by Don Taylor, 24 March 2015 - 10:25 PM.

[BigC]

If you bought the Celestron 70az in black from someplace you can return it,I would.Then get the Amazon Green Celestron 70az package that includes the Accessory Kit for a total of $70!

 

If you do return it another suggestion is getting the eq model which is easier to follow planets and stars with and can be motorized later.

 

Nothing wrong with a 70mm as a Zhumell Aurora 70 was the first scope to show me Saturn-that was a great beginner's scope 'cause it came with RA motor ,moon filter  everything one needed to get started.

 

Although for limited budget and all,the Celestron Firstscope 80 EQ is a very nice value and still not too big.Of all the modest refractors an 80mm x 900mm EQ set has more light grasp,littleCA,not too heavy or awkward,and cost under $150,less on sale or used.

 

 

The Meade set of 5 MA eyepieces work well for not much money as do the Celestron Kellners(often marked Wide Angle in block letters) in 9,10,15,20,and 25mm.The lightweight az scopes with fixed point yoke mounting of the tube easily become unbalanced using heavy eyepieces.

[Jon Isaacs]

I have owned a Celestron Power seeker 70 AZ for a while.  I replaced the tripod legs with some I made from 2x2s, that made it much more stable and also taller.. I had about $6 in parts..

 

The eyepieces are as described.. The diagonal is of limited clear aperture, 14 mm, so eyepieces like a 32 mm Plossl vignette badly..

 

A better tripods, a decent diagonal and a few decent eyepieces and it does an OK job..

 

Jon

[macdonjh]

jmccown,

 

I don't own the Celestron 70 refractor; however, it seems like you should be able to remove the focuser from the end of the telescope tube.  If you can do that, then simply remove the screws that hold the finder in place, drill holes on the other side of the tube and remount the finder.  Then you can use your scope "left handed".  As for the abandoned holes where the finder used to be, either fill them with short screws and nuts from Home Depot, or simply cover the holes with small patches of tape.  I've done both in the past and either method works well.

[jmccown]

I thank all you gentlemen who have responded and suggested I get better eyepieces. I recall from my previous life as an astronomer that the eyepieces that come with a scope are often inferior. I had seen the ads for the Astro Tech value line Plossl eyepieces. I wasn’t sure if they were good but after reading Don Taylor’s suggestion I think I will (Maybe 25mm, 15 mm, and 9mm?).

 

Jon Isaacs, thanks for the info about the diagonal. Do you have any recommendations for a replacement diagonal? 

 

We've been having thunderstorms and tornadoes in Oklahoma. So not much additional observing. Last night I finally got the 14" gibbous disc of Venus resolved. Haze in the sky plus a very bright crescent moon made it difficult to starhop for DS objects. Easily resolved the 14" double Mizar in Ursa Major. 

[useraaaaa]

yea... Green Powerseeker Celestron 70az is 49.99 + free shipping on amazon

got it 2 days ago

 

one interesting  thing - focuser is threaded for  m42x0.75, so if you have camera with ring..

 

 

 

 

about barlow lens, someone mentioned it supposed to be set before (or after) diagonal

Edited by useraaaaa, 26 March 2015 - 10:14 AM.

[BigC]

You may use the barlow before or after the diagonal,try both and see which works better for you in that scope with each eyepiece.I find those long barlows sticking up from a diagonal to be awkward.  But that is sometimes where it must be. And sometimes not.Look for additional lightweight eyepieces. My Amazon Green 70 was a customer return and about $37 shipped.Bought it as something for quick grab-n-go including as a scope that could be left in the car for unexpected viewing opportunities without much concern.

 

I once used stacked barlows in a 70/350 to view Venus as a pretty well-defined crescent low in the western sky.Point being that barlows and 70 scopes can be useful.

 

I am thinking of trying a runner's leg or wrist weight as a sliding counter to balance the tube when using a heavy eyepiec. The Celestron Luminos 10mm for instance completely overwhelms the elevation adjust/ments-but the view is good!Really ,in the f10 scope the simple Kellners do very well for little cost -if you shop carefully.

 

These az-el refractors might benefit if someone could devise a simple,cheap way of sliding the optical tube for better balance.

[jmccown]

Thanks for the suggestion about using the barlow before the diagonal. I tried and it works!

 

Had some very nice views of the moon and Jupiter tonight at 105X. Between the bright moon and the hazy sky, I didn't bother trying any DS objects tonight.

 

Hopefully the skies will be clear this morning. I will try to get up before sunrise and have a first look at Saturn through my new scope.

[tnakazon]

Glad that the optics on your Celestron Powerseeker 70AZ worked out well.  My experience with this scope differs from yours and others on this thread.  I got mine from Walmart in late 2012 at a Black Friday sale, but when I first tested it out, the moon looked a bit soft and I couldn't cleanly split Algieba with high magnification, even after using a better mirror diagonal and Plossl eyepieces (and testing for pinched optics).  Fortunately, I had a Vixen Space Eye 70/700mm achromat that I bought used the same year and had completely forgotten about until then.  Comparing the views through both scopes and using the same diagonal and eyepieces in both OTAs confirmed that my Powerseeker 70 was a lemon.  My friend also got his from Walmart at the same time and found the performance on his sample to be wanting, compared to his Orion Space Probe 76/700mm Newtonian.        

[Abhat]

I have Celestron Astromaster 70AZ.  It is F/13 and not F/10. The optics are outstanding. I can go to 150X on Jupiter without any image breakdown. That scope is crazy good at splitting doubles. The mount is also more stable than the yoke mount.

[jmccown]

I found a good temporary solution to the short tripod problem. Cinder blocks make a stable platform.

Attached Thumbnails

• 

[jmccown]

Had an excellent view of Jupiter tonight. With both 105X (20mm EP plus barlow) and 175X, I could see both equatorial belts, and also could usually glimpse both North and South Temperate Belts!

 

The seeing was very good tonight. That plus the fact Jupiter was near the zenith made for some good viewing. Apparently my cheap scope can take magnification quite well when the atmosphere is steady.

 

Hoping to get a glimpse at Saturn this morning. Haven't had a chance yet.

 

UPDATE:

 

Had my first view of Saturn with the scope this morning. Unfortunately, last night's steady atmosphere had gone away and the seeing was not so good. I could easily the rings at 105X and 175X but could not see Cassini's division nor any cloud bands. Titan was there, however. Hopefully with a better atmosphere will be able to see more detail and some of the fainter moons.

Edited by jmccown, 30 March 2015 - 07:07 AM.

[BigC]

How many scopes have been dismissed as "no good" when it was simply the seeing conditions were to blame ?

 

As for the magnification, you may or may not be getting 105X  .I have read that the effect of a barlow is stronger when used before the diagonal.Usually guesstimated as making a 3x act as a 4.5x.Haven't really checked that myself.And the barlow effect is sensitive to optical path placement. I have a couple older Meade barlows that vary the power by moving the barlow lens inside its own tube.Then there is the question of how accurate the barlow maker was in stating power andin which position relative to the diagonal.

 

You might be getting closer to 150x,hard to tell.

 

If you do buy the accessory kit with 15 and 9 ,those with the barlow will go as high as that objective is going to do.Watch for a good 25 or even a 32 for nice low power AFTER you swap in an unrestricted diagonal.A  normal star diagonal will flip the image unlike the correct image diagonal but will not vignette the light.

 

You are off to a good re-start , enjoy the  view!

[jmccown]

Thanks, BigC. I can believe that I'm getting 150X with the barlow before the diagonal. Just comparing the apparent size of Jupiter with the size I get with the 4mm eyepiece without the barlow.

 

Do you have any suggestions for a replacement diagonal?

 

 

How many scopes have been dismissed as "no good" when it was simply the seeing conditions were to blame ?

 

As for the magnification, you may or may not be getting 105X  .I have read that the effect of a barlow is stronger when used before the diagonal.Usually guesstimated as making a 3x act as a 4.5x.Haven't really checked that myself.And the barlow effect is sensitive to optical path placement. I have a couple older Meade barlows that vary the power by moving the barlow lens inside its own tube.Then there is the question of how accurate the barlow maker was in stating power andin which position relative to the diagonal.

 

You might be getting closer to 150x,hard to tell.

 

If you do buy the accessory kit with 15 and 9 ,those with the barlow will go as high as that objective is going to do.Watch for a good 25 or even a 32 for nice low power AFTER you swap in an unrestricted diagonal.A  normal star diagonal will flip the image unlike the correct image diagonal but will not vignette the light.

 

You are off to a good re-start , enjoy the  view!

[BigC]

Really ,just about any star diagonal will do. I have paid $10 to 60 from new cheap mirror ones to prism to used dialectric diagonals. Check the CN classifieds,astronomics retail website,ebay ,or  amazon.

[BigC]

Look in CN classifieds,call astronomics,check ebay and amazon. 1.25" star or 90° diagonals can be bought for $15 to $150 ,cheaper used. 

PM sent 4/2 

Edited by BigC, 02 April 2015 - 10:58 AM.

[jmccown]

Very good view of Jupiter again tonight. Anxious for the moon to get out of the way and sky to clear so I can see some deep sky objects. 

 

If I can wake up, will have another look at Saturn. Hoping to see Rhea for the first time with this scope.

[jmccown]

I have semi-dark skies at my house to the North and east. Not so great to the South and Southeast.

 

Had  a nice view of M81 and M82 at 35X tonight. Also a decent view of M44.

 

I have ordered the Astrotech Plossls in 25, 15, and 9mm focal lengths. Also the star diagonal recommended by Big C.

Edited by jmccown, 07 April 2015 - 11:05 PM.

[Patricko]

Glad to hear you are still enjoying your refractor! I'm sure the extra eyepieces and diagonal will help even more. Keep looking up!

[jmccown]

Ugh! Got up at four am to have a look at Saturn. Went outside to see....lots of clouds. I can just imagine how the astronomers on Venus feel. LOL.

 

Right now, the moon will probably prevent it, but I would like to see Rhea and Dione. Also want to see some cloud belts, and Cassini's division.

 

Since the moon is exiting the evening sky, would like to see some more galaxies, including NGC 3077. It's too bad M31 and M33 will have to wait until the late summer.

[BigC]

An interesting fact I discovered while looking at my gear is that the correct-image diagonals supplied with some other telescopes have less restrictive internal baffles?stops? ;anyway the clear hole through which light passes. So not all owners of correct-image diagonals need worry about vignetting.Evidently Celestron chose to cut costs in every way possible for these special green tube 70az scopes. Noticed the L.L.Bean Celestron appears externally the same-anyone have one ?

 

Those three plossls you ordered are really going to improve the views.25,15,and 9 are very common because those sizes are very useful in a wide variety of scopes.

 

The plastic eyepieces included in the Amazon Green edition of the Celestron 70AZ  are absolutely the cheapest I have ever seen in any scope. But considering the retail price and free shipping you know it has to be a reduced cost product.

[jmccown]

 

The plastic eyepieces included in the Amazon Green edition of the Celestron 70AZ  are absolutely the cheapest I have ever seen in any scope. But considering the retail price and free shipping you know it has to be a reduced cost product.

 

Actually my Celestron 70mm Powerseeker has a black tube. Bought it from Woodland Hills and I had to pay shipping. But I think other than the colour, its the same thing you got.

 

I agree the eyepieces are very cheap. But not the worst I have ever seen. I bought a Meade 6" f/8 Newtonian about 30 years ago. The eyepieces were terrible. I think they were "Meade Achromatics"?

 

The only decent eyepiece I have ever received that came with a telescope was a 27mm Kellner that came with my 8" Coulter Dobsonian.