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Skywatcher HEQ5PRO Tripod and Extension pillar.
There are a few marks on the tripod legs but not really noticable, the eyepioece/spreader tray has paint flaking off
But could be cleaned and repainted, it didnt bother me, but I am lazy.
I am selling as its not getting used as it should be and I find I use the excuse that it takes to long to carry it out
and setup, but in reality I think I am just losing interest.
As it is a heavy object collection from TS25 (Hartlepool) is preferred.
But if a courier collection service is available buyer pays the costs and arranges pickup I am happy as long as money has been transfered. Also I am prepared to travel a reasonable distance to meet for exchange.
Price £400 ONO I will not split
Hi to everyone, I used to do some astrophotography in the past with a Celestron AVX and DSLR but after few month had to give up for several reasons, including light pollution (I'm living in zone 3 east London), and also working shifts. Now I want to start again, and this time more serious. I've been searching around for a couple of months to choose all the gear and I'm quite happy with the list so far although it's a bit over the price I planned at first.
I will get an William optics Z73 with his 50mm guide scope, a flattener/reducer 0.8, light pollution filter IDAS D2 and as camera I will use a Canon 600D modded and I will buy a ZWO 183MC Pro, after so much research, I'm very happy with the scale and framing I will get with this combo, but I'm starting to get confused with the mount.
My first idea was to go for an HEQ5 Pro, as my previous experience with the AVX has been awful, then I realized that the FLO, sells that mount with belt modification and also some cleaning and tuning if required, I heard that it's a big improvement over the stock one and the price it's ok, but another important factor for me it's portability. Unfortunately, my garden doesn't allow me to do much so I will need to carry around on trolley, for a km walk, I'm a strong person and been doing plenty of time with the AVX, so my confusion came recently when the iOptron mounts entered my radar. I start comparing the heq5 pro with belt, with the iOptron cem25EC and the CEM40 without encoders, and I'm so unsure of which to buy, the cem25 seem to be the equivalent of heq5 at least speaking of payload, but in some threads I read people saying it's a bit fragile so kind of remove it from the equation although the weight it's interesting for my situation, then the cem40, seem to be quite similar on weight to the heq5 but with higher payload and that's interesting too as I will buy a C11 at some point.
Now it will all come down to the accuracy of tracking I guess, how the heq5 and cem40 would compare on tracking and guiding? If the cem40 it's better, I would probably go with that since it holds more and would last longer as I don't plan to get anything bigger than a C11, but if the skywatcher it's better, I could decide to go for that, and when I move to a place with better garden then get a second mount with higher payload.
Apologise for the long post and my english.
Thanks for reading.
I am upgrading my mount for my observatory. I will be doing AP primarily but to be honest, I also enjoy some visual. I need about 30-40kg capacity. I had my heart set on the ridiculously expensive 10 Micron 2000 (coming in a about 12k when you figure all the extras needed). Something seemed wrong about that price....!
I now have an opportunity to get a Mesu 200 Mark II. The mounts engineering looks unquestionable and I have yet to hear anything bad said about these mounts. The price is also very attractive compared to the 10 Micron. My issue is the control. I’m going to be honest - the controller looks rudimentary (and with no screen, controlling from the computer for visual may be annoying). I have no knowledge of Sidereal technology at all. I am very close to purchasing this mount but I would like some feedback on user experience regarding the software and control of the mount. I note the new version will have the Scitech I controller but I thought (perhaps incorrectly that the older version has the II controller). I am not sure if this is significant or not.
Opinions and feedback greatly appreciated.
[A few more photos are in the imgur album]
Made this telescope for observing sunspots. The Sun gets projected onto a piece of paper after bouncing from 3 mirrors inside the frame.
It's compact, light, takes only a few seconds to point at the Sun, and sketching sunspots is as easy as circling the spots on a piece of paper.
It can even project the Moon:
The design is inspired by a commerically available telescope, but I’ve done all the designing myself, just for the fun of it.
Sunspotter is full of little details that make it interesting. How do you fix the eyepiece in the exact place where it needs to be? How do you keep the lens in place and perfectly aligned?
Building the telescope was a lot of fun, I’ve learned to use a jigsaw, X-Carve and a 3D printer. The plan is to use it to complete the Astroleague Sunspotter Observing Program, but unfortunately I completed it at the minimum of a Sun cycle, and won’t see any sunspots until next year.
Magnification: 75x Size: 41cm x 41cm x 15cm Weight: 1kg Design: Keplerian Projection size: 75mm Materials needed:
Lens: Ø52mm f=750mm achromatic doublet Mirrors: 1, 2, 3 Eyepiece: Baader 10mm ortho 1.5m² of 10mm plywood Wooden glue 5m of PLA filament 12 nails Compressed air Isopropyl alcohol Tools I used:
Jigsaw with a 30° bevel capacity X-Carve 1000 3D printer A laser pointer Clamp Learned modelling basics in:
LibreCAD Easel TinkerCAD Fusion 360
Part 1: Choosing the lens
The idea of a sunspotter is that the light goes through the lens, travels inside the telescope, bouncing from 3 mirrors, enters an eyepiece and the image gets projected on one of its sides.
The distance the light travels before entering an eyepiece is the focal length and it determines the size of the telescope.
I chose a Ø52mm f=750mm achromatic double. Observing the Sun doesn’t require a large aperture, 50mm is more than enough. I wanted a high magnification and went for the longest focal length I could find, which was 750mm. Achromatic doublet design is what people use in refractors. If it is good enough for a refractor, it’s definitely good enough for my project.
With the focal length chosen I could design the wooden parts. A drawing showed that the frame needed to have sides 30cm long, but I wasn’t sure about the placement of the mirrors and went for 31cm sides, planning to shorten the light path as needed by adjusting mirror positions.
This is the LibreCAD drawing of the layout of parts on a piece of plywood:
Part 2: Building the base
Having a drawing of the base in LibreCAD, I printed the drawing 1:1 scale on multiple A4 sheets of paper and glued them together. I transferred the drawing to a piece of cardboard and cut it out.
Applied this cardboard template to the sheet of plywood, and cut out two parts with a jigsaw.. I’m not an experienced user of jigsaw, and couldn’t manage to cut half-circles accurately enough. Even worse was that the two parts were very different. I didn’t want the frame to randomly tilt left or right when adjusting its altitude, and had to spend a lot of time with sandpaper to make the halves as similar as I could.
Glued the two large parts with three small parts in the middle. Additionally nailed the parts and the base was ready.
Part 3: Frame
The frame is simply a triangle made of three pieces, with short sides cut at a 30° angle. Most jigsaws can cut at 45°, but not at 30°. Had to buy a new jigsaw with a 30° bevel capacity.
Cut out three sides, cut short sides at a 30° angle, but didn’t put them together just yet.
The lens needs to be perfectly aligned with the Sun-facing part of the frame, otherwise the Sun projection isn't circular but elongated.
My solution was to carve a hole with a little step as shown on the image.
The inner hole is Ø46.5mm, the outer hole is Ø50.8mm.
The outer hole is the exact size to let the lens fit, but with a little bit of friction. Had to carve several holes to find the minimal size the lens could fit in.
The step is just large enough to have enough surface for the glue to keep the lens in place, I didn't want to reduce the aperture too much.
I used an X-Carve for carving and Easel for modelling.
With all 3 sides ready, I could assemble the frame. It appeared that my 30° angle cuts were not very precise, but after some sandpapering the sides started fitting together alright. Glued the parts together and left them to dry for a day. To apply some pressure on the joints, I wound several twine loops around the frame really tight, made sure all sides fitted well together and left it to dry like that for a day.
Part 4: Mirrors
When selecting mirrors I was looking for the smallest mirror that fit the cone of light. Small mirrors are a lot easier to place, and they let me better control the length of the light path. I considered using elliptic mirrors, but they were bulky and really hard to place. All mirrors are first surface mirrors, otherwise planning their locations would be a lot more confusing.
This was my original plan of placing the mirrors:
As you can see, all the angles and distances were carefully measured, and I wanted to simply make mirror holders of those exact dimensions. This was clearly a bad idea.
I 3d-printed some parts like this:
And only later I realized that the frame angles are not exactly 60°, and that there are drops of glue along the edges that don’t let me fit the pieces deep enough in the joint between the sides.
I cut angles from all the mirror holders:
After I put the first mirror in place I realized the angles are all wrong, and that I needed to re-do the holder. Separating the mirror from the holder was a huge pain, which resulted in an accident. The mirror fell off the desk and got damaged.
Luckily, only the back side got damaged, the front side was still working:
The final designs of mirror holders looks like this:
The holes in the front surface let me apply pressure on the back of the mirror if I ever want to separate it from the holder. The recesses collect the excess glue to avoid mirror skewing when gluing them.
All other holes are simply to save the filament.
Part 5: Placing mirrors
What I learned is that you can’t plan positions of several pieces with high precision and just hope that it all comes together. I needed a feedback about the precision of mirror positions.
I used a laser pointer to verify mirror positions at each step.
In the picture you can see that the laser is firmly set in a hole in another piece of wood, with layers of isolation tape on the tip of the laser pointer to make it stable. A clamp holds the piece of wood in place, ensuring that the laser ray goes in the same direction as a solar ray would. A crosshair of black thread at the center of the lens ensures the laser goes exactly through the center of the lens.
When placing each mirror, I marked the spot where I expected the laser to end up. While gluing the mirror holder to the frame, I kept the laser as close to that spot as possible. If for some reason, the laser couldn’t hit the expected spot, I did my best with placing the mirror, and recalculated locations of the following mirrors.
I saw the first sunspots after placing all the mirrors and simply holding an eyepiece in hand.
Part 6: Eyepiece holder
I tried eyepieces of different focal length and liked the picture I got with a 10mm eyepiece the most.
An eyepiece needs to be in a very exact spot to produce a sharp image. At this point it was obvious that my frame doesn’t match the model, and that I didn’t even know what exactly was wrong with the frame. I didn’t want to rely on the model and moved forward with trial-and-error.
I printed several parts to hold the eyepiece, with different eyepiece locations:
The part in the photo was a total disaster. It needed quite a lot of filament, at the same didn’t have enough surface area to be glued to the frame, and not enough surface area to hold the eyepiece firmly.
The next iteration was a lot better:
This part has a lot more surface area, and needs less filament to be printed. I intentionally printed the hole for the eyepiece too small, and had to sandpaper it a little bit, to make the eyepiece stay firmly fixed.
Adjusting the focus is done by sliding the eyepiece up and down until the Sun becomes a circle with well defined borders.
Part 7: Dust
All optical parts should be kept clean. Dust on the mirrors and the lens will make the image darker. Dust on the eyepiece will show up as artifacts on the projected image. Unlike sunspots, the artifacts will not move with the Sun. To clean the eyepiece I used compressed air. To clean the mirrors I used isopropyl alcohol.
Part 8: Fire safety
Don’t leave devices with magnifying lenses lying around. Once the Sun happened to be in such a spot that its light went right through the lens, burning through the cap of the eyepiece. Luckily, nobody was hurt and no other damage was done.
Part 9: Future work
Build quality of the base is very poor. The frame tilts sideways when adjusting its altitude despite all my efforts. I’d like to build a new base, but leave all the work to the machines. I already have a model for an X-Carve to make both base parts, compatible with my current frame:
A notch along the edge of the half-circle should eliminate the tilt. The precision of the machining should make the base very stable. Maybe next year, when sunspots become a common daily sight, I’ll get to this project.
Thank you for reading this far!
I hope you enjoyed it.
My club's Atlas is stuck on the date 11/13/2099. Last night was 6/28/2019. Every time I reset the date and started the 3 star alignment the scope chose Vega and then pointed to the western sky - sorta wonky. When I tried a second star it aimed at a totally wrong part of the sky. I went back to date and it had reset to the11/13/2099 date. The mount has a working GPS module. I went through all the menus and there was no place other than the " sub menu to attempt to replace the errant date. After five tries I gave up. Apparently the GPS was accurate to withing a stride or two. What should I try next? I know my club; they'd rather stuff it in a corner than take the time or money to fix it. So it will be m time and my money. I used the mount several times this year and had no problem.