michael8554

If you're guiding, the PHD2 Developers say 5 arcmins is good enough, pretty much what theastrodragon said. But if you're not guiding, as good as you can get, but there comes a point where it's too difficult to get consistently better. Michael

I prefer the darker but not black level background in the second one, and it looks sharper to me. Michael

The 600D has a lot going for it, apart from banding on long exposures in hot weather, but it was the first model to have a spring loaded sensor, previously they were shimmed. Consequently getting the sensor back in position after modding is quite tricky without some sort of vernier gauge. Get it wrong and you'll have a tilted sensor. So if you want to DIY, maybe start with a 450D for the experience, still an okay camera, and work up to a 550D, which still has shims. Michael

Canon 6D is a great imaging DSLR, with big pixels, and low noise at high ISO, I have one. But those big pixels make it unsuitable for shorter focal lengths. Image scale is about 5.4arcsecs/pixel at 250mm, In other words, seriously Undersampled, yielding coarse resolution images 2.4arcsecs/pixel at 555mm might be okay. I use mine at 1280mm FL, which is 1arcsec/pixel, some might consider that a tad Oversampled if anything. Michael

There are eight (8) classes of laser products according to British Standard. They range between Class 1 and Class 4. Health and Safety regulations place restrictions on lasers above Class 2 (<1 mW). The laser provided with your barndoor is 5mW You're absolutely right, insane beam, these can blind airline pilots. Southampton has an airport, so do us all a favour. Michael

Laser pen /pointers are for indoor use, for pointing at Powerpoint presentations etc on a projection screen. So you only need a green dot on the screen, beam not necessary. Some people buy illegal high powered ones they use at night, these can blind airline pilots, you don't want one of those. Michael

That's true. Either way he's got a solution. Michael

8" Celestron telescope sounds more like an SCT. These scopes have a massive focus range, so your DSLR will come to focus. The focus knob has a range of maybe 40 hand twists. So try during the day pointing at a distant object, (bottom of the garden is too close) and don't be afraid to do a lot of turning of that focus knob. As you get to each end of the range you will start to feel much more resistance - don't force it, start back the other way. You will then need a further adjustment on a bright star. Michael

No No Yes New feature for next year's model - auto target tracking rate ? Michael

You need a camera with 10um pixels, not sure that exists, or one with 5um pixels Binned 2 x 2. Michael

I suggest you go into the Custom Functions menu and turn on "Long Exposure Noise Reduction". After you have taken your 30 second exposure, the "Light", the camera will automatically take another 30 second exposure, but with the shutter closed. This black "Dark" contains the same noise as on your first exposure. The camera automatically subtracts the Dark from the Light, which removes most if not all the noise, and saves this to the memory card. Don't forget to switch this off for normal daytime shots! If you want to get the best from your camera, acquaint yourself with at least it's most basic features such as Live View, by reading the Instruction Manual.:-) A hard copy comes with the camera, there's a pdf on the CDs that come with the camera, or you can download a pdf from Canon USA. Michael

You're not shooting with LiveView on are you ? Michael

Perhaps PHD2 can't move the mount while the "Hand Controller" is open ? Untick Show Hand Controller ? The Track Mode is showing AltAz, is that going to work? Up the PHD2 Guide Pulse Duration to 5000, just to be sure it isn't moving. (Presumably those aren't your real Lat Long, should be around 51N, and 000deg 45secs W) Michael

You might want to leave the DSLR screen flipped out, that lets a bit more cooling air get to the back of the camera. Turn off the display of course, and watch out for it catching on things as you track and slew. Michael

As Dave said. Astronomy often involves looking at very dim objects, so adding a lens to a scope to make images upright, comes at a price of more light absorption. And a star looks the same either way up ! Michael

Is there a power LED on the mount and does it go out just before the handset resets ? That would be intermittent contact of the power plug. Michael

Have you installed a suitable driver for the Neximage 10 ? Michael

Wot he said Michael

Skywatcher recommend a 3 Amp power supply. A 1 Amp power supply will be over loaded when you slew. Michael

Hi Tom, Don't understand that, is that Social Distancing? Out of interest, what figure on the scale did the wedge end up at? Michael

Hi Tom Loosen Red, Yellow, and Green (both sides of the wedge) and turn Blue to lower the tilt plate. I've a vague memory that it should be set to 90 - 32 = 58 on the scale. But that does not compute with this wedge, maybe it does with other brands: If this wedge was set to 90 on the scale, the tilt plate would be parallel to the ground, and the scope would be pointing straight up. At Lat 90 North Pole the scope would then be pointing to Polaris. So 90 on the scale does mean Lat 90, the scale is correct. Similarly at the Equator Lat 0 it would be pointing at the horizon, so would have to be set to 10 on the scale, and the north tripod leg lowered a bit. So I don't know why your scope is located at Lat 32, the wedge is set to 32, but it's pointing high. Michael

PHD2 shows arcsecs and pixels for the Statistics. Pixels is how far stars have moved on the guidecam, arcsecs is the same thing but in , erm, arcsecs, which translates to how elongated your imaged stars are in RA and Dec. People get very excited when the Stats are showing 1 arcsec or less. When using the PHD2 Drift Align I find it can take several minutes per measurement for the RA line to stabilise back on the x axis, up to that point the Dec and RA lines are moving relative to each other, and so is the reported PA. A few arcmins of PA is a tiny adjustment, you may find just rotating the mount PA knobs a tiny bit without loosening anything will be enough, you'd be amazed how bendy most mounts are. And avoids it all changing when you tighten up ! PHD2 is complicated, looked at SGP and similar, and PEMPro for PEC, but far too complicated for me. Michael

There does come a point when further fettling of the mount worm and PHD2 settings is no longer effective. So long as the RA and Dec RMS are similar you'll have round stars, though they my be fatter than you'd like. Certainly too many poor frames at the moment to give up refining. Is the main camera imaging during those 2 minute Settling periods, or is it paused? I don't know SGP, so I can only suggest setting the Dither to after every zero frames if it will let you, and try the settling to 1 pixel since nothing is going on. Michael

Forgot to mention the Periodic Error is about 100arcsec peak to peak, if your mount has PEC I'd give that a go. The guidelogs are kept for 3 months, so that old guidelog from May last year with the Cal on it is way gone. Settling - you've dithered, which has moved the mount further than normal guiding, so it will take a few seconds to stabilise the guiding at the new position. The settling reports when the guiding has got to within a certain fraction of a pixel. 2 seconds is a typical exposure. Michael

Yes on a permanent setup you can reuse the Cal for a goodly time, but seeing the Cal might help the diagnosis. In a permanent setup the PA shouldn't change of course, and doesn't need to be better than 5arcmins if you're guiding. Yours is 10 arcmins, so a small one-time tweak would help, you really don't want to bother with Polemaster with a permanent setup. As you haven't used the mount in a long time maybe slewing it around for a while to redistribute the grease might help. The big evenly spaced spikes in Dec are worrying, do you have Backlash Comp set in the mount, this should be set to zero as it conflicts with the PHD2 Backlash Comp and guiding? Or dragging cables? Are you Dithering with an external prog? I can see the settling, but not the Dither command. Also Settling is taking 2 minutes sometimes! Are your settling settings too stringent? The frequent Star Lost messages suggest the Seeing was poor, or that your 1 sec exposure is too fast. And the very choppy guiding might also be a consequence, Chasing the Seeing perhaps? Do a new Cal at Dec 0 after nudging North to take up any backlash, run the Guide Assistant, accept the recommendations, then guide for 10 mins without altering anything, and post the log if it's not looking good. Michael