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New 70mm Maksutov from Spectrum Optical Instruments

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#1 Jim Riffle

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Posted 03 December 2022 - 12:49 PM

I thought I would share my impressions with my latest telescope purchase.  I saw an earlier thread regarding if this scope was any good.  Jim Riffle

 

Spectrum Optical Instruments --- ExploraPro 70mm Maksutov

 

Specs: 70mm x 750mm f/10.7 or just (2 3/4” x 30” fl.) 

Measured diameters:  Entrance dia. of Mak corrector 70mm.  Exit diameter of corrector is 72mm.  Diameter of primary mirror is 78mm.  Painted aluminum tube 3 1/2” dia. X 7” long.  Supplied diagonal is std 1 1/4” roof prism type for correct image orientation.  3 nice metal barrel eyepieces of 20mm, 10mm and 4mm focal length + 2x Barlow lens.  Secure snap-on main lens cover. Finder is red dot type with variable brightness adjustment.

One arm fork mount is nice diecast aluminum.  Elv and Az slow motions are by metal worm gear sets with clutches that must be loosened to move mount and re-tightened for worm gears to grip.  OTA is centered over tripod and the outward fork allows for beyond zenith viewing.  Nice size center leg lock tray with 3 eyepiece holes.  Tripod/mount weighs 5 pounds.  OTA is 2 pounds. Both together easily a one handed carry in and out.

 

Tripod legs are extruded aluminum and very solid, with only 1 single leg extension for a short tripod, but fine for a low chair/stool use. Rubber tips at ends.

 

Overall impression:  The box was so big, I thought for sure that they sent a refractor by mistake.  Turned out to be just good packing with a fully assembled mount/tripod.  The better instrument quality became obvious as I unpack.

 

Bench tested optical tube in double pass auto-collimation against an optical flat with 200 line Ronchi light.  Very good correction is noted.  Made sure to focus at infinity prior to test and diagonal removed for test.  Noted slight collimation error which was adjusted out with 2.5mm hex wrench (not supplied). 

Daytime visual @ 2 mile target. Focus was smooth and slow motions had no noticeable cross talk when reversing directions (good).  Focus was very touchy/critical with a slightest motion making a difference in sharpness. Some annoying azimuth torquing at leg mounting hub was minimized with ¼ turn to tighten 3 leg attachment bolts with 5mm hex wrench (not supplied).  Noted some stray light from inside of baffle tube.  It was threaded, but with too fine of threads to be effective.  Close focus distance tried and came in at just 68”!!!!  FOV at that distance is just barely a silver dollar. Macroscope!.

 

The cell phone adapter has a really solid bayonet system of attachment to the eye end of 20 and 10 mm eyepieces.  You need to remove their rubber eyecups for access.  Unfortunately the eyepiece projection distance is not adjustable and I needed to make a 0.20” thick spacer washer and then find a longer coupling 1/4-20 screw.  Now I can get the full-circular evenly illuminated field view on my camera screen.  The Sarblue 60 “out of the box” remains my favorite for daytime cell photos.  The Bluetooth shutter fob worked great.

 

Evening Astronomical use:  I had a cheap 25mm eyepiece on hand I used for deep sky.  The Pleades fit in nicely in a non cramped field at 30x.  I could just see the elliptical companion galaxy next to M31 as well at the elongation plane of M31.  The finder had a fat red dot and also some parallax which annoyingly diminished it's accuracy.  The slow motion controls were nice to use.  Next Jupiter.  The 10 mm (75x) showed the 2 main cloud bands and pin point moons.  With the 2x Barlow @ 150X it was just as sharp.  I tried the 4 mm @200x with less detail (ran out of light/contrast).  Might have been my 1948 eyesight.  I noticed no image flaring or degradation from this roof prism diagonal.  The slow motions were invaluable at centering and tracking.  The elevation flex shaft was very close to the side of my head and precluded using my left eye unless I rotated the diagonal to the left side some.  The moon views were very crisp.  There is no discernible image shift focusing at high power.  Image damping in about 2 sec.

 

Mods:  Aside from tightening the 3 tripod leg bolts, next day I loosened the worm mesh on both axis (not for the average hobbyist to try).  When the morning temp got down to 35F the focusing became very/too stiff.  I changed out the greases on sliding baffle tube with light oil and it was still stiff after cooling.  The plastic rear cell hole had shrunk on the brass focusing bushing as the temp dropped.  Next morning  I had to carefully machine about.0015” from the O.D of the brass to allow good low temp focusing.  Also had to remove grease from focusing screw and use light oil.  I also removed a primary mirror baffle extension tube which just screwed on (it wasn't needed and so lets in more light now).  This small 70 mm Mak is now a nice little keeper to me.

 

Tip:  Mirror alignment adjustment is by 6 screws on plastic rear plate.  The 3 higher screws are locking screws.  The lower 3 are for adjustment.  To readjust, lightly loosen the top 3 firstly before adjusting a lower screw and then re-tighten top locking screws lightly at completion.  The mirror assembly weighs just a few ounces so go easy on tightness.  2.5 mm wrench needed.

 

Overall:  I am nicely impressed with the engineering in this.  They had needle bearings on hardened races for the slow motion clutches.  Nice solid metal worm gear sets with necessary adjustments.  Great optical quality, nice eyepiece set, secure cellphone coupler method, though not at the correct spacing for my I-phone.  I like the tripod leg stability and useful eyepiece tray.  I like the fact the OTA  is centered over the tripod for minimal vibration.  I especially like the low price and high overall quality.  Mine cost $138 + tax on EBAY with 3 day delivery. 
But this is just a small/inexpensive  2 3/4” dia. Maksutov, however with optical quality par with a 3 1/2” Questar I owned 35 years ago.  I said optical quality, not performance.\

 

About the reviewer:  I have been more of a deepsky observer/astro-imager over the years and not so much a visual solar system viewer.  I do appreciate sharp-coma free optics and tiny tight stars.  I have professionally built and sold many 12” Maksutov telescopes in the past.  I currently own a Celestron 127mm Mak that has very fine optics and a older C-8 used for Fastar CCD imaging from the past.  I also have both 60 & 70mm Sarblue Maksutovs and a custom 50mm Mikro-Mak on a Mikro-mount.

 

As a side note, I personally do not favor the Maksutov Cassegrain optical design for daytime spotting telescopes due to their required internal light baffling and secondary mirror shadow.  Both of these issues lower contrast.  Refractor optical designs are superior in comparison as visual spotter scopes.

 

One image shows Sarblue 70 on right with Spectrum 70.

Attached Thumbnails

  • 6 feet.jpg
  • elv gear.JPG
  • mountain2.jpg
  • baffle1.jpg
  • 70mms.jpg

Edited by Jim Riffle, 03 December 2022 - 12:55 PM.

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#2 flightlogic

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Posted 03 December 2022 - 01:04 PM

What a great detailed review.  With Christmas coming... I see some gift giving for younger astronomers.  (and letters to you asking for custom mods!  just be warned in advance... it's the internet after all)

Nick in Flagstaff.



#3 wykbbb

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Posted 03 December 2022 - 03:46 PM

Thanks for the review!

 

How would you compare Sarblue 60, Sarblue 70, and ExploraPro 70? 

 

Previously, 90mm maks were the smallest maks that were easily available. If someone was looking for a portable mak, would you recommend the 70mm or 90mm?

 

Can the alt-az mount be moved without the slow motion controls?

 

Can the prism diagonal be replaced with a mirror diagonal?

 

What is the outer diameter and length of the optical tube?

 

Scope is on sale at Walmart for $131, with holiday returns until Jan 31.  


Edited by wykbbb, 04 December 2022 - 11:24 AM.


#4 Jim Riffle

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Posted 04 December 2022 - 10:44 AM

ANSWERS:

The mount can be moved in both axes by hand after the slow motion "clutch" knobs are loosened.  Then scope can be pushed to target, but then for slow motions to work again you have to re-tighten "clutch" knobs (a simple 1/4 turn/easy to grip/no image shift).  So perhaps the word clutch is better called clamp.  The Sarblue 70 has a true clutch in comparison.

The rear end accepts normal or prism 1 1/4" diagonals.  But I compared both types on Jupiter and saw no image splitting/flare with their prism type.

Tube  size is 3 1/2" O.D x 7" long.  The metal tube is only 6" long.

If the 90mm has the optical quality that this 70mm has, choice is obvious if you have the $.  For astro light gathering, brightness scales by square of objective diameter eg 49 verse 81 so the 90mm is about 65%  brighter view, theoretically.

Your first question deserves a very long reply.  I will try to work on that one and post later.  I did try to answer it.  So don't buy anything today.


Edited by Jim Riffle, 05 December 2022 - 10:31 AM.


#5 Jim Riffle

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Posted 04 December 2022 - 02:46 PM

70mm Sarblue (SB) compared with Spectrum O. I.(EP)------ 70mm Maksutov Cassegrain Telescopes--------

 

MOUNTS/tripod

The EP has much stronger/stiffer/rigid legs. This helps in the 2 sec EP vs 4 sec SB damping times. EP tripod tray is bigger and has better locking leg support with 3 eyepiece holes. Tray on SG even though metal is small, useless and flimsy by comparison. The center post on the SB adds unwanted weakness.
Mount for EP is a 1 arm fork type with OTA mass optimally centered over tripod. SB has large offset mass from tripod center. Slow motion controls on SB are higher gear ratio for fast daytime centering and have nice clutch to grab and point scope.  EP has 2X finer control which is superior for high power pointing and most importantly there is little cross over/unwanted interaction between Az and El adjustments while reversing direction. The SB is way worse in this respect when trying to center at high power, eg planets/moon. Both have a sliding dovetail lock for re-positioning and removal of OTA. Both tripods have rubber tips on leg ends. Damping time on SB is about 4 sec and EP is 2 seconds. EP tripod/mount is 1 pound heavier @ 5 pounds +2 pound OTA. The SB tube/mount are 6 pounds. I grade the EP 70 mount easily as best.

Optical tube assembly. Both are nicely built. I like the SB gloss grey color better than EP satin black. The EP tube is noticeably shorter at just 6” vs SB 7 1/2” for the aluminum portion. This is to be expected for the 30” EP vs 40” SB focal length difference. Rear cell/end on SB is metal and the EP is plastic which caused its focus screw to get very stiff to turn at cooler temps. The primary mirror baffles are different diameters with the EP noticeably smaller. I was concerned over this, but deepsky observations showed no issue between the 2 different diameters. Both show some internal light reflections that slightly lowered daytime contrast in views. For some reason they use very fine internal glare threads which don't work as well as coarser threads.  The baffle tubes are very thin walled and may not accept coarser threads. I added black flocking paper on the inside of the SB baffle and also inside the diagonal mirror input tube. The SB diagonal has recessed/safety detents on the input plastic tube. There are also 2 lock screws (plastic) to securely lock the diagonal position in place at rotational 12 positions. The EP just has one diagonal locking screw, but it is nicely knurled metal. Both scopes show no objectionable image shift when reversing focus knob rotation (in and out focus movement).  The EP diagonal has a high quality roof type prism for correct daytime views.  The SB is a mirror type with reversed R-L image. Both work well @ higher power on stars.

I bench tested both optical systems with 200 line Ronchi double pass against an optical test flat and they were equally superior in correction. Way better than ETX 90 I had and some older typical Celestron Maks I've seen. But in comparison, my latest Celestron 127 SLT is flawless. But both 70s ain't got no flies on em.  Especially for their price.

 

The 2 SB eyepieces are plastic barrel, but decent enough FOV and quality for great views.  The 4 EP eyepieces all have metal barrels, plastic top ends and decent quality. I did use my own cheapo 25mm on each 70 for a nicer low power/higher contrast views. The SB does have a 1.5X Barlow lens that can be used visually. It is in the included cell phone photo adapter assembly. The EP has a separate 2x Barlow.  I prefer it combined with the 10mm for (150X) high power views. The SB tops out at 100X with its included 10mm or perhaps 150X with the photo Barlow. For old eyes, 150X for a 70mm is pushing my contrast limit. Optical quality/astro performance is a draw for my 2 purchased samples.  What can you see on Jupiter?  I saw just 2 major cloud bands distinctly and the 4 very tiny dot like moons.

 

I did find a nice full aperture 95mm solar film filter on Ebay that nicely fits both scopes with slight paper shims. Remember to cover/block your finder before pointing at sun or you may fry the SB cross hairs or you own hairs. While on finder subject, the SB finder is great till it gets dark and then you can't see the crosshairs.  It also has a nifty adjustable arm for preferred finder placement. The EP finder is a cheap red dot that has a fat dot and also has right to left parallax which makes it useless for high power pointing accuracy, but ok for daytime.

 

So you may see that I sort of like features in both. My favorite is the ExplorPro 70mm. Even with the mods to the brass focus bushing mentioned in earlier post. Just can't go wrong for the money. The average person won't notice any difference between the two. These are just small imported 2 3/4” Maksutov Cassegrains that deliver nice $1/power views. Questar not.  AstroMak not. But I admire each of these for what they are.  A know that a decent 4" spherical long focus Newtonian will probably beat these for astro viewing eg 114mm Power Seeker Newtonian (f/8 all for around) or Sky Scanner 100mm (f/4 parabola for deepsky). but these 2 Maks are cute one handed grab-n-go rigs with no counter weights and easy to get thru thru door.

 

Need to mention: The Sarblue 60 is cool since you can open it and look inside. How novel is that????  The all plastic doesn't hurt their performance one bit and excellent optical correction is same as the above 70s, just less astro light gathering. Nice wider FOV and contrast for great daytime cell phone photos. Great reviews are found on Amazon.  I have taken nice photos with it, but not space here to add them.  Of the 3, this is my choice for daytime spotter and simple cell phone photos.

 

I also have an Omegon 60 Mak which I like (I switched it over to smaller .965” diagonal and eyepieces).  And then I have a 50mm MikroMak telescope with a tiny .600” eyepiece set and diagonal, sitting on 1/4” axle GEQ MikroMount /w dual axis drives. That whole rig fits in the palm of your hand.

 

Note:  I skipped a comparison of the cell phone camera adapters that come with each.  These are eyepiece projection type.  Results depend on your phone size/lens and user tweaking etc.

Attached Thumbnails

  • 70x70 1.jpg
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  • 70x70 2.JPG
  • 70x70 3.JPG

Edited by Jim Riffle, 05 December 2022 - 10:45 AM.

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#6 wykbbb

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Posted 05 December 2022 - 10:54 AM

Jim, thanks for the comparison of the Sarblue and ExploraPro. It's good to know they have good optical quality.

 

The optical tube of the ExploraPro 70 is really short at 7". The length is smaller than Sarblue  60mm mak and some 50mm  finders.  

 

Until recently, 90mm was the smallest readily available mak in the US. As you mentioned, these 50-80mm maks will gather less light than than 90mm maks.   What do you like about these smaller maks?  I'm curious about your opinions, because  there is less discussion about smaller maks. 


Edited by wykbbb, 05 December 2022 - 04:12 PM.


#7 Jim Riffle

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Posted 05 December 2022 - 08:29 PM

Well, after building a series of large12" AstroMaks myself, I like about any size Mak.  The small ones are cute and crack-me-up.

In past years I was a technical consultant to Celestron International in Torrance when Alan Hale was at the helm.  I got to test many imported new products for them and suggest improvements to the Chinese and other vendors.  Mainly what mistakes/problems they needed to fix and how to best do that fix.  They weren't doing Maks then, just Newtonians, refractors, binos.

 

They would send blue prints along with product where they showed putting the 90 degree engraving at 87.3 degrees from the 0 engraving on a dec circle.  In other words, they copied a competitor's mistake while measuring to copy that product.  I would try to explain the why behind things and the standard reply is, we don't want to know why, just tell us what to do for this fix. Imagine the next copycat competitor making a compounded measuring error from the new errant copy's mfg errors.  And so it goes.

 

Fast forward 20 years and they are definitely getting their Mfg acts together and currently cranking out great stuff at absurdly low prices.  Like these 70mm Maks.  As a side, I used to machine cast iron steam engines (machinist kits) made in England.  Out of pocket for a kit was ~$700 plus another $100 in sundries, and about 80 hrs + machine shop time.  I usually machined the difficult crank shafts firstly per image.  All that cost and precision work to get a nice steam engine that ran.  Now you can buy beautiful miniature engines from China for 1/2 that cost and they are finely cast/machined brass RTR finished!  Blows me away. 

 

So a $1/power Mak Cass is a steal for my own curiosity.  The tinier, the better. Sorry to wander out there a bit, but wanted to paint some context to view the current imports from China. 

jim

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  • KIT1.JPG

Edited by Jim Riffle, 05 December 2022 - 08:34 PM.

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#8 34degN

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Posted 06 December 2022 - 01:08 AM

So Sir, I have a question to ask you. Do companies send you these mini Mak so you can review? Or do you buy these small mini mak yourself? example the Sarblue and the current 70mm from Spectrum.

You did mention you not into "toy" scope like these, then may I ask, why do you bother spend your money buy it if you not into it?


Edited by housewife, 06 December 2022 - 01:08 AM.


#9 wykbbb

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Posted 06 December 2022 - 10:18 AM

Jim,

 

Ah, you used to build AstroMaks and consultant for Celestron. That explains why your review was full of technical details and suggestions for improvements. I think it's great that while you have built large maks, you can still appreciate mass-produced small maks.  

 

Have you tried imaging with small maks?  A couple of people have tried imaging with Sarblue 60, but the small FOV at high magnification and the distortion caused by 0.5 reducers are obstacles.

 

I'm amused that the ExploraPro 70 mak is shorter in length than some finders.  I have a 50mm f/5 refractor that is 10.5" with the diagonal. I'm not sure why  50-70mm refractors are considered real telescopes, while these  50-70mm maks are written off as "toys".

 

Thanks for providing info about your experience with Chinese  manufacturers (telescope and miniature engines). I play ukueles, and the same thing happened in that sector. Mass produced ukes from China have improved in quality over the years.  


Edited by wykbbb, 07 December 2022 - 04:46 AM.


#10 34degN

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Posted 06 December 2022 - 04:37 PM

@ Sir wykbbb,

 

I have the Sarblue 70mm mak that Sir OP have.

 

Here is the spec sheet that came with it.

 

I will be honest with you, this scope at 1000 focal length and f/14, I was able to see planet bigger and more details than two f/5 scope that I tried (which I end up return both) and keep this so called "toy" mak.

 

mymak.jpg


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#11 Jim Riffle

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Posted 10 December 2022 - 06:40 PM

Wifester, What a strange question?  I haven't gotten a free telescope since I can remember. I usually designed/built them anyway.

 

The SB 60mm and a 70mm Maks mentioned in my threads were purchased from Amazon, paid with a credit card. The other 70mm Mak was from an Ebay vendor and paid by PayPal.  All up, I probably got $450 into the 3 little Maks after rebate coupons. This, just to satisfy my curiosity, since I made a few 50mm miniature Maksutovs in the past. The last 3 professional scopes I made went for well north of 80K each, so I figure I got a little space left to still indulge $150 "here and there" in my waning astro-hobby years.

 

The last big scope purchase for me was a C-14 with fork mount (last set of fork castings Celestron had). I bought it all from Celestron at dealer price so that I could develop the Fastar14 optics for it and do test images. I later converted it to full computer control using an FS2 control system.  Same as I used on all the Centurion 18s fork mounts.  Image attached.  Sold it awhile back to a neighbor 2 doors down the block.

 

So after building up to 28" dia. computerized non-visual scopes for research, it is great change to downshift to 1 1/2" to 2" scopes, and yet still fully functional as a small challenge.  Coincidentally,these are the same size scopes I made in 4th grade from Edmund lens sets with the simple to follow Sam Brown lens experiment book.  This was back when you HAD TO make your own telescope in order to get one.  Well, war surplus was there then.....

 

So cost, just like size is relative to our whims.  If you go small enough, you can have one of everything!

 

jr

Attached Thumbnails

  • Fastar 14.jpg
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  • mikroMak.jpg
  • 40mm Newt.jpg

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#12 Jim Riffle

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Posted 10 December 2022 - 07:38 PM

HA, I forgot that I do professionally work on small telescopes in the surveying instrument range.  40mm or less aperture refractors

 

Since getting out of the Navy in 72 my first job/profession was a surveying instrument repairman for Keuffel and Esser, San Francisco branch. My previous ATM hobby years really got me that job.  Attached image is two Wye levels , one 1910 ish and the other from the 30s that I restored as antique collector items for myself.  I did this daily at K&E and later graduated up to theodolite-man where arc second precision was need in tiny 6" spaces.  Next image is the world's smallest theodolite in my hand, a Kern DKM-1, a 5 arc sec reading 20x instrument.

 

Now, how do you do 1-5 arc second measurements with a pre ED glass era objective lens of 40 mm or less and @ 20x?  Consider that the theoretical resolution for such a lens size and needed magnification is many times more?..! 

 

It is in the split cross-hair and targeting and of course instrument build/calibration precision.  I continued to do this repair/restoration and calibration into my 60s and still do it for fun on now for my own collectibles that I buy at times on Ebay.  So I do own and collect a multitude of 50mm and lesser telescopes.  So that is where I come from saying small aperture $150 telescopes are "toy-ish".  Wasn't till I walked in the other room an saw some of them on display!  Ha.

jr

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#13 Jim Riffle

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Posted 11 December 2022 - 08:53 AM

For WYKBBB,

 

Yesterdays solar image with Sarblue 70mm and cell phone.  Also attached is the SDO-HMI image from today's Space Weather.com site to compare.  I used a full aperture $12 solar film filter from China over the entrance.  I also remembered to cover the finder lens!  The grey image was colorized.

 

But the photo coupler is from the Spectrum 70mm with the custom aluminum spacer to get full image circle.  The image is cropped and rotated match SDO image.

jr

 

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  • sun111.JPG
  • SDOhmi1898.jpg
  • adapter 001.JPG

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#14 Jim Riffle

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Posted 11 December 2022 - 09:01 AM

Above solar images were not to sharp after uploading.  Attached is a cropped and hopefully sharper image from SB 70

jr

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  • cropped.JPG

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#15 12BH7

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Posted 11 December 2022 - 09:31 AM

Thanks for sharing those stories.  I know you are operating on a more professional,  but I see you also enjoy tinkering as well. I liked the post about getting the steam engine parts. I can't tell you how many things I've taken apart so I can save the parts for some other project.

 

When I was a teenager back in the 70's I worked as a machinist at Jaeger's Optical on Long Island. There were tons of old optics just laying around and I had access to all the lathes. I had fun but all that stuff was eventually lost to time.

 

Thanks for posting.


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#16 Jim Riffle

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Posted 13 December 2022 - 03:02 PM

YES, A. JAEGERS

 

You know, I should have mentioned A. Jaegers (king of optical surplus).  That is cool and must have been a treat to work there then.  My biz purchased perhaps 6 of the 5" f/5 kits from them.  I liked the giant/long travel focusers, but modified them with nice large knurled aluminum focusing knobs, 2.7" to 2" reducer bushings  and drilled and tapped for 2 fiber tipped screws to minimize the focuser tube wobble.  I also made up a 6" f/5 of theirs, but it had too much color for my taste and all the 5 inchers were better in that respect.  Image of one of them on a scope going to India.  Long time ago, back in the film photo days.

 

jr

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  • 10 inch folded.JPG

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#17 Tiebreaker

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Posted 20 January 2023 - 09:53 PM

Hello Jim (primarily but all opinions welcomed!),

 

Thanks for the very thorough comparison of the Explorapro 70 and the Sarblue 70!  I'm considering getting one of them as an airplane travel scope and would like to know a couple more specifics. 

 

First, which tripod will collapse down the most?  I see that the EP is a two part tripod whereas the SB is three parts - does that mean the SB is smaller when collapsed?  I'm trying to see if either one will fit into a piece of luggage (carry-on size preferred but checked luggage would be doable as well).

 

Second, I know you like the EP mount best.  The EP OTA is more centered over the tripod which intuitively (to me anyway) would make it smoother in azimuth motion over the offset SB OTA, correct?  I'm looking for smooth movement both in fast slewing as well as under slow motion movement.  I know not to expect buttery smooth motion at this price point but something that minimizes binding and backlash.

 

Thanks in advance!  



#18 34degN

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Posted 21 January 2023 - 10:10 AM

Sir Tiebreaker, I seet he Explorapro 70mm you get more value for the money. Here what it comes with. In walmar it on sale for $150

 

03f81108-fb55-4574-b048-79003e63d9a8-87c


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#19 BSeward

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Posted 21 January 2023 - 06:26 PM

Amazon has the Explorapro 70mm for $100.99!
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#20 34degN

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Posted 22 January 2023 - 06:18 AM

Now I'm tempted to buy it, for $100 it worth to give it a try, who knows it might turn out good optics.


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#21 BSeward

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Posted 22 January 2023 - 11:40 AM

Mine works very well. My friend just got one for himself, too.

#22 wykbbb

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Posted 22 January 2023 - 11:49 AM

Now I'm tempted to buy it, for $100 it worth to give it a try, who knows it might turn out good optics.

Can I ask why you keep looking to  buy another telescope?  Have fun with the beginner scopes you already have, learn the night sky, read some astronomy books, attend a star party, etc. You can worry about saving enough money  to buy an intermediate telescope later on. 

 

 

 

Amazon has the Explorapro 70mm for $100.99!

You decided to get the Explorapro 70mm after all. In your first Explorapro 70  thread, lots of people said negative things about this scope without even testing it out. It was a real eye opener to read Jim's detailed review. 

 

$101 is a good price for a small mak.


Edited by wykbbb, 23 January 2023 - 10:26 AM.

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#23 34degN

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Posted 23 January 2023 - 05:03 PM

Mine works very well. My friend just got one for himself, too.

Hi there Sir, can you share to me how is the mount of the explorapro 70mm? Tbh I'm iffy because that mount look like it plastic and not sturdy. But then I never touch it so like how do I know it not sturdy. So I want your opinion since you own the scope. And how was the eyepieces optic?

 

Thank you Sir.



#24 BSeward

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Posted 24 January 2023 - 11:58 AM

The mount is completely metal. Very sturdy and the slow motion controls work perfectly. The eyepieces work fine, I don't use a Barlow, but I did test it with my laser collimator and it did the barlowed laser trick just fine. I gave the 4 and 10mm eps away, and use my collection of eyepieces I already have. The phone mount is a bit cheesy, I wouldn't bother with it, personally. The little doohickey that snaps the phone shutter works fine, though.

At $150.00 it's a good value, at $100.00 it's an amazing deal.
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#25 BSeward

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Posted 24 January 2023 - 11:59 AM

Be aware, the image is not inverted like a normal astronomical telescope.


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