bobro

The beer can was for a bit of fun, but sticky tape does the job of adjusting height. 🙂 Yes, a 130P reflector scope (various manufacturers) can be modified to come to focus with a DSLR. One way is to take a hacksaw to the tube, cutting something like 35mm from it at the main mirror end.

Sometimes a weight can be improvised (the can is full of sand). Note - this image shows a DIY guided EQ2.

Sounds like something isn't quite right with the setup. I started imaging with an EQ2 with economy motor and 650mm fl scope. Exposures of 30 sec were typical without star trailing with 60 sec on occasions. You mention exposures ruined by vibrations, so something must be causing vibrations. Is the camera shutter triggered remotely? Is the scope balanced (slightly east heavy in RA can help)? An out of balance scope could cause judder. My EQ2 mount settles within a few seconds of being touched, though it is the Meade tubular leg version rather than the SkyWatcher type. What about polar alignment - is this reasonably good? Poor polar alignment can show as star trails. The economy motor speed can be a bit tricky to get correct as the motor can run slightly fast initially. If the speed is not correct star trailing will result. Issues with motor speed or polar alignment will show as star trailing. Mount vibrations may show as an image that looks slightly out of focus. If the RA worm gear adjustment is too tight it can result in RA judder and star trailing. An unguided Star Adventurer is unlikely to be an improvement over your EQ2. Upgrading the EQ2 motor to one with accurate RA speed could be useful as it would save the fiddle of RA speed setting: https://www.firstlightoptics.com/sky-watcher-mount-accessories/skywatcher-ra-motor-drive-for-eq2.html

Interesting thread. I too imaged with a Canon EOS1000D, experimenting with temperatures of over 20 degrees C. The amount of obvious pixel noise at higher temperatures was high, though I aimed for 20+ subs with dithering and used kappa-sigma stacking to eliminate a great deal of the pixel noise. Darks weren't taken. More recently I'm using an IMX183 mono uncooled camera. Due to the amp-glow darks are essential, with the darks eliminating the amp-glow and not being important in temperature for removing it. A couple of days ago I experimented with stacking an image using darks that were taken about 4 degrees C cooler than the image. The result was pretty good in eliminating pixel noise though there were a few obvious pixels that still showed up as not being corrected. Dithering and kappa-sigma stacking would easily have corrected these pixels, though darks at the correct temperature did the job. I'm by no means an expert imager, so won't be able to comment on detailed questions. Perhaps my conclusion is: whilst theory is great, efforts to comply with theoretical opinions aren't always so obvious in the resulting images, so it can be a good idea to find out what works for your setup and the final result by experimenting. 🙂

Refractor telescopes bend light depending on wavelength. IR wavelengths can result in slightly out of focus images with refractors, hence the need for IR cut filters. Reflectors don't have this issue, hence an IR cut filter isn't so necessary to stop this. A CLS filter attempts to cut light wavelengths from local light pollution, so can be used for imaging galaxies where colour reproduction is important. UHC filters (not all are the same) limit wavelengths to the blue and red part of the spectrum. This is good for imaging emission nebulae as these produce mainly red and blue wavelengths, but not so good for galaxies where the wider wavelengths/colours are not passed. Hope this helps.

Here is a wip - 60 minutes taken this week with a 150PL f#8 on an EQ5. Camera is Altair Hypercam 183 mono non-cooled. Colour to come. There is obvious horizontal banding on the composite image, but isn't on all subs. A power issue perhaps? I haven't imaged that much with the camera, but this is the first time I have seen the banding.

The 150P has a focuser with an eyepiece extension that can be unscrewed, allowing a DSLR to be closer to the OTA and achieve prime focus. A130P doesn't have a focuser that allows this, so the DSLR image plane will be too far away from the OTA and won't achieve prime focus. A Barlow can help, but has disadvantages as explained above. Shortening the OTA to move the primary mirror upwards, again as explained above, allows a DSLR to achieve focus. A well known issue with current 130P Newtonian scope designs when trying to get a mirrored DSLR to focus at infinity.

That looks a really good capture at 4 min subs - good detail and nice round stars. Perhaps a bit too strong on the blue in colour balance?

Although my CG5 (EQ5) is perhaps a bit light for carrying my 150/1200 PL for DSO imaging purposes (though that's how I use it), it is fairly solid and handles the OTA reasonably well for long exposure DSO imaging and should be fine for visual. Planetary imaging uses short exposures and is less demanding on mounts than DSO imaging. A suitable tracking (not goto) stepper motor for the EQ5 is: https://www.firstlightoptics.com/sky-watcher-mount-accessories/single-axis-dc-motor-drive-for-eq5.html

Doesn't the 150P come to DSLR focus by unscrewing the eyepiece extender and attaching an adaptor as already purchased by the op? Removing the eyepiece extender brings the camera closer to the mirror. Same as on my 150PL. Not sure if it would work with a CC added though.

Adhesive PTFE (Teflon) strips along the inside length of the focuser are a useful and low cost way of tightening up holding of the inner tube and therefore eyepieces/cameras. Something like 5mm wide and 0.5mm thickness. The strips stick to each other to increase thickness if necessary. There may already be something similar inside the focuser as an example.

Yes it has been asked before. Likely responses: 1> Go with it, but expect less than impressive results as the OTA is a bit of a challenge for an EQ5 - result could be disappointing images 2> Go for a lighter/ shorter FL scope with the EQ5 - makes imaging easier 3> Get a more substantial mount, e.g. EQ6, to go with the 200P - still not the easiest imaging with a scope of 1000mm FL, but the mount helps. Personally I would go with a shorter focal length scope - makes life easier when starting out.

RA or DEC on an EQ5 should be easy to move with the cable controls - even with the cables disconnected and just the remaining stub to move with fingers it should be easy. Tightness may be due to the worm gear (backlash) being too tight. If this is the case rotating the RA/DEC control over 360 degrees could result in some periods of slack and some of tightness. Adjusting the worm is a bit of a compromise, especially for astrophotography where backlash doesn't help imaging. For visual it isn't so much of an issue. Some info here:

For straightforward processing Doug German's videos are a great start. He doesn't use GIMP, though GIMP has the same sort of processing functions Doug uses. For gradient removal see: https://www.youtube.com/watch?v=yTEVMH_WE80 Below is your image processed with the methods Doug proposes (gradient removal and star masking) using GIMP, plus saturation increase and stretching. I'm no expert at processing and others will do much better, but it gives an idea of what can be done with the image - some of the nebulosity around Sadr is becoming visible. Of course a night with less moonlight will help as image noise will be less.

Images are looking very good considering your setup, targets and time of year. With basics nailed, the question is what's next? An increased number of exposures should be straightforward to achieve and will improve SNR. Longer exposures will help with noise though will probably require guiding. Brighter targets (higher SNR) will result in visually improved images. Darker nights/sky will also make a good difference. Perhaps a combination of choices for a greater improvement, though at this time of year a brighter target may be appropriate. Winter can make a dramatic difference to images! Great stuff! Bob

My EQ2 has dual axis guiding (but not goto). As guiding controls the position of the mount by making small adjustments to the speed of the simple DC RA motor or turning on/off the DEC motor, stepper motors are not necessary (they are necessary for a goto mount or a non-guided mount for positional accuracy). Note: I haven't used the EQ2 for some time as I now use an EQ5 (stepper motors) with AstroEQ - a very good solution though care has to be taken with choosing the stepper motors. Here is a link to more info on the guided EQ2: http://guiding.web.fastmail.co.uk/

Hi, The original article describes how the design works with an f#4.5 reflector used as an example. Results will also depend on the frame size of the camera as coma gets worse as the distance from the image centre increases. If you go ahead it will be interesting to see the results. For testing an aperture mask (a piece of card with a circular hole across the front of the scope) could be used, for example, to reduce the scope from f4 to f4.5 to see what difference this makes. Bob

Welcome! Here is a link to a very similar telescope and mount if you can't find the Tasco one: https://www.telescope.com/assets/product_files/instructions/29260_01-09.pdf

What make is a 200 DP? (Sky-Watcher do 200P and 200 P-DS. with different focusing requirements.)

Been there with my CG5 (EQ5). The EQ5 RA axis consists of a central core (with bearings at top and bottom) and a cylinder around it that mates with the RA worm gear. With the RA clutch ON the cylinder and core are locked together, allowing the worm to provide RA drive. With the clutch OFF the central part is free to rotate in principle, though can be sticky due to the lubrication (grease) between the cylinder and central part. Depending on the grease and with the clutch off, it can be a little difficult to balance the RA axis as it can seem sticky. Using lighter grease (or even removing most of it) makes the outer part of the RA axis rotate more freely with the clutch off. However, this doesn't affect operation with the clutch ON as the inner and outer parts are locked together. So your mount is operating as expected - no need to do anything so long as it is operating correctly when the clutch is engaged.

Even with a full Moon, it seemed a shame to 'waste' clear skies, so I decided to see what my (uncooled) Hypercam 183M would produce with a (rather old) Astronomik Ha filter, not expecting very much in the way of results at a reported temp of 14 degrees C with the uncooled camera. 150PL scope (f#8), 18 subs @ 6min, 11 dark, 10 flat, x3 binned, not dithered. The resulting image (no noise reduction other than kappa-sigma stacking) surprised me as I was expecting it to be pretty awful due to noise. I suppose x3 binning helped, but it must be down to the low noise of the IMX183 sensor, although a stretched single sub looks horrible with hot pixels.

In higher light pollution environments there's no advantage in long exposures as multiple shorter exposures produce the same results (in signal/noise), potentially allowing a lower spec mount to be used. With the scope/camera you mention in a high light pollution environment, there may be no advantage in exposures longer than, for example, 30 seconds. On the limit perhaps for a Star Adventurer but an HEQ5 could be overkill if you are looking for a portable mount. Guiding is typically not necessary for short exposure times, helping to simplify the setup. The IDAS D2 filter will help to some degree, though I don't know how much. Perhaps someone else has experience of this.

Doesn't CdC connect to the mount for positioning and APT to the camera for imaging, with (for example) an APT connection to a PHD2 guiding program server for dithering? Perhaps your setup works in a different way?

The 150PL won't come to focus with a Barlow body inserted into the eyepiece holder and DSLR due to lack of inward focuser travel. To mount a DSLR unscrew the eyepiece holder and screw a standard M42x0.75mm T-ring to the M42 thread on the scope. https://www.firstlightoptics.com/adapters/t-rings.html

Looks like a Jones-Bird design. If so, there will be a corrector lens at the bottom of the focuser tube. Although reflector telescopes often do not have enough inward travel to attach a DSLR, the x2 magnification of the lens doubles the effective length of the focuser travel and it seems you have been able to focus with a DSLR. Unfortunately the image quality with this sort of low cost telescope is not normally very good and there's no point in trying to magnify the image as it will only show up shortcomings even more. Have fun with it as it is, though a telescope more suitable for imaging is the way forward.