michael8554

Depends if you have the thin lockring in place or not:

Indeed, changing the guidecam's orientation to RA and Dec will mess up the Calibration and hence guiding bigtime. Michael

Screen grabs are often helpful. For example it's noticeable that Dec and RA are closely mirroring their movements. Posting your guidelog, including a Calibration and Guide Assistant run, will provide much more info. As Alan mentioned your guidescope, that model is on a wobbly finderscope-type mounting, that may be the problem (we're talking microns of wobble) Michael

We went to the excellent Christmas Lights at National Trust Stourhead. They had set up stunning lighting and displays around the garden, took about 2 hours to walk around. Here's some of their Christmas Constellations:

Hi Craig. Here's what the framing of M27 looks like with your scope and ZWO: For larger DSO's try your DSLR. The ZWO is probably more sensitive than a DSLR, so that's not the limiting factor. When you were shooting Planetary you were probably using the ZWO in Video Mode, with very fast exposures. For DSO's you use a Long Exposure mode, with exposures of several minutes rather than milliseconds. Your mount is not really suitable for exposures that long, you will get star streaks rather than star points. So experiment with exposures, staring at say 10 seconds, increasing until you start to see streaks, then back-off. Use a DSO Stacking Software to stack lots of those exposures, enough to total at least 5 minutes, and see what you get 😆 If you're having trouble focusing on stars, start with the moon, then move to a bright star such as Capella. Eventually, as others have said, you'll want to move over to a more suitable scope and mount. Michael

https://openphdguiding.org/phd2-best-practices/ https://openphdguiding.org/man/Basic_use.htm Michael

Never mind the weather, use it as a chance to investigate. Make some new Flats with settings and T-shirts as sugested, and apply to your previous Lights, to get an approximate idea if you're on the right track. Michael

Don't know where you read that, not on this forum I hope ? Michael

The calculator I found seems to have been pessimistic in advising 12sq mm. But calculating for least load is not best either. What happens when the mount slews and draws lots more current and the voltage drops? Mount runaway. Michael

Yes, there seem to be several ways in NINA. https://nighttime-imaging.eu/docs/master/site/advanced/dithering/ In theory David's 350mm FL image is very undersampled at 3.83arcsecs/pixel, but doesn't half look good ! (We're going to the Christmas Lights at Stourhead, so I'll be driving through Westbury tomorrow evening ) Michael

Let's say 10 amps including the dew heaters, over 20 metres. I found an online calculator that gave a figure of 12sq mm for a 0.5V voltage drop at 12V. For example, probably the heaviest cable you find in a house for 240V is 6sq mm. 25M of 10sq mm black or red from Radio Spares costs about £60 each. As wulfrum says, investigate a safe mains supply to your mount position, google "Temporary Garden Electricity" Michael

It's often impossible to focus a camera on a Newtonian telescope, because the image is too far away from the closest the camera can be mounted. So often a 2X Barlow is used to extend the image outside of the focuser. I think that using a 0.5X Reducer will have the opposite effect to the Barlow, which is why you can't focus. Make sure you have the camera as close as possible to the focuser, remove any extensions that are on the focuser and try again. Michael

We need to know: 1) how long is the cable run from the bench supply to the power hub ? 2) How much current does all your equipment pull ? That's the important figure, hopefully not more than the hub and bench supply will take. 3) Do you know what kind of plug the power hub requires ? Michael

Yes I use a Canon 6D. They produce low noise at high ISO, so I use ISO 1600. Dither the DSLR 12 pixels, and instead of Darks, shoot Bias and load as Darks in your Stacking software. Image scale with your 120ED is okay. Not sure if the image circle will fill the Full Frame sensor, but apply Flats and crop the final result if necessary ! Michael

Hi Rookie Although I agree with the complete application of corrections that vlaiv and alacant have posted, just Lights and Flats should give a pretty good correction. Since you have tried various stacking softwares, I suggest your Flats are wrong. Sounds like you are using a DSLR, so shoot on the AV setting to get the correct exposure, and adjust the flatbox and T-shirt to make that about 1 second. Post a link to your subs ? Michael

Always have a Plan B. Look up "Polar Drift Alignment" using a high-power reticule eyepiece. And "DARV Polar Alignment", which uses your DSLR. To help find Alignment Stars you need a Finderscope, accurately aligned to the imaging scope. Hope you're not using the Finderscope dovetail slot to mount the Guidescope, much too wobbly for accurate guiding. Also instead of spending hours taking Darks, Dither the DSLR 12 pixels, and take Bias (capped off at fastest shutter speed), and load these as Darks in the Stacking software. To speed up Star Alignment, just SYNCH on a star near your target, then a GoTo the target should be in the FOV. Great results despite !

Hi Colin It was probably this one: https://www.cloudynights.com/topic/639160-ascom-drivers-for-a-meade-lx600/#entry10702820 Talks about Plate Solving with SGP only able to slew close to target, not able to get spot-on. Keep up the good work ! Michael

When you go outside at night and look north, there is only one star, not particularly bright, about 45 degrees up, and well separated from others, that looks to be a possibility. That'll be Polaris. Michael

A frustrating late afternoon of dodging the rain, clouds, and my horizon. I roughly focused on the moon earlier on, but didn't get a cloud-free dusk view until about 1630. Managed a few snaps through tree branches, but I broke off to fine-focus on Altair, and then the clouds rolled in. Sets here at 1715. So this blurry effort is more of a setup and test shot for Sunday and Monday:

Shurely the Moon, Jupiter, and Saturn, over The Great Pyramid At Giza ? Nice framing Peter. Michael

Many years since I last used the free EOSMovieRec software, to make high quality uncompressed 5X LiveView AVIs, so I dug it out for the Jupiter/Saturn Conjunction. Working out how to use it was a bit of a struggle, but here's how: It seems you must switch on your camera BEFORE opening MovieRec. There are various versions, I used the 0.3.3 Beta x64 version on my Win 7 x64 Bit. Laptop, it also worked on my W10 x64 Tower PC. 1. Install the software. 2. Plug in and switch on your camera in M Mode. 3. Run MovieRec. 4. Double Click the icon top left with three dots in it, to create a Folder to store the AVIs in. 5. To record video, click on the "Write!" button, to stop, click on "Write!" again. 6. Or set a record duration by ticking the "Time Timer" box, and selecting a duration in the adjacent box. 7. The software doesn't seem to shut down cleanly, so I used "Task Manager" and "Stop Task" Fingers crossed for good weather ! EDIT: Looks like each time you open MovieRec, you need to go back to the Folder you created in step 4, and Save again, or you get a "Can't Record" Message. The software has a few bugs it seems..... Did some tests on a distant Landmark this morning (clearish skies !), and looks like 5X may be too much "magnification" for my setup, so will record on 1X, and take normal" Raws as well. Michael

I NEVER spend a night imaging without first taking an exposure at max ISO (12800 or 2560 for the 70D). 30 secs to 1 minute is usually enough, doesn't matter if the stars trail so long as you have something recognisable. Quite apart from taking the wrong target, it confirms the framing is correct. Michael

On the 21st it doesn't get dark until about 1800, Jupiter will only be about 10 degrees above the horizon in the SW, and it sets at about 1900. Are you sure you'll be able to see Jupiter/Saturn from your location ? At my Wiltshire location I'll be fighting with trees, I may well start at sunset, about 1700,

Probably worth putting in the WANTED section ? Michael

The PHD2 developers expect best guidescope focus, and a PHD2 Guide Assistant run will suggest improving focus if the HFD is high. Remember once you have the imaging and guiding cameras both in focus at the same time, in future you only need to adjust the imaging camera focus - the guide camera will then be in focus too. Michael