fwm891

Single 10 min sub guided on the comet. RGB original but the colour was bad so converted to greyscale.

M-Machine have a huge range of tubing they will cut to length as required: http://preview.m-machine.co.uk/CATALOGUES/metals catalogue.pdf

Just managed to get M45 and Venus last night before it dropped below the roof line. Great in a pair of bines. Needless to say that Venus swamped M45 so I've tried to merge some older M45 subs with the Venus m45 images from last night too. Venus M45 from last night is a stack of 4x 5 sec subs, WO 73ZS with Nikon 800E - image cropped. I've replaced the combined image with 4x 5sec stack with a 6x 1 sec stack, shows Venus better and obscures less of M45

Probably not much difference but I use -20°C as a standard. Easily reached in winter and in range for summer nights.

@Anthonyexmouth I imaged the comet with a Celestron RASA 8 at f2 with an ASI294MC Pro cooled to -20°C. Processed in PI. Image is cropped to remove stacking edges

Animation made up from the one hour track last night

Compilation of 60 x 60 sec subs aligned on the comet in PI. All processing in PI. Also a star aligned image using the same subs to show it's movement.

Clear again so again tried an object (M44 - Beehive) that I can't remember ever shooting before and M97 / M108 pairing, a couple I've not looked at for some time.

Hi Tony, I've just tried this in PS CS3. What I've done: Opened your image duplicated the layer and made the blend method screen Applied 1st levels adjustment layer - lightly Applied 2nd levels adjustment layer - again lightly Applied 3rd levels adjustment layer - again lightly (Better to gradually apply levels and keep the noise down) Applied Hue Sat adjustment layer Applied a colour balance adjustment layer Applied a curves adjustment layer - tiny shadows adjustment Then tweaked the upper levels adjustment layer for mid tones. Flattened and saved as small tiff Francis M13 The Great Hercules 26-3-20 -proc.tif

Tried imaging the Leo Trio. Not been to this area for some time - quite a change. Image is built up of 27 subs, equal mixing of: 120, 300 and 600 second subs. Captured with SGPro, processed in APP (stacking and calibration) PI (colour work) and a levels tweak in PS CS3.

For you @alan potts with a bit more saturation (as far as I dare) Francis

Finally got the dark, flat and flat/dark calibration frames for this image. This has allowed me to do a less severe crop taking away just the stacking artefacts. Final processing carried out in APP (calibration and stacking), PI for background correction (DBE, ABE SCNR etc) and a final levels check in PS CS3. Hope you like.

Both images with William Optics ZS 73 + Flat 73 A x1 flattener. Nikon 800E (no filters) on an iOptron CEM25P guided (PHD2) via 9x50 finder guider (asi 120mm) Shot as RAW frames and processed in PI and PS CS3. M101 had 16x 180s subs, M51 had 14x 120s subs. Both frames have been cropped

Sixteen sub frames 60 and 120 seconds mixed. Stacking on the comet head in PS-CS3 Fan shaped flair on the stars caused by cables

Thanks Mark - I hope you and yours are too 🙂

I've combined the previous nights data with last nights ( now totalling: 3hrs 40 mins ). I still have no darks, flats etc for calibration but I pleased with what's there at present - hope you like Processed in PI and tweaked in PS and back to PI...

Nice one Brian 👌

Thanks Mick, Yes pushed really hard in PS and definitely needs more subs long and short. I'll try processing through APP that seems to deal with noise better. Process in APP and PS. Less noise but background dust has gone. More data needed...

This image set was captured on March 15th but only just got round to processing the subs. Subs: 6x 120s, 5x 300s and 5x 600s combined in PI and finished off in PS CS3.Taken on March 15th 2020Celestron RASA 8 and ASI 294 MC Pro @ -20°C, IDAS NB-1 filter.iOptron CEM60 mount.No dark, flats or bias frames shot.

Only if you can't increase the stepper pulses by finer micro steps

Noticed these while walking the dog this evening. Quite strong colour (I have added a little saturation too) They had faded a bit by the time I got back and grabbed a camera but still a good display - best I've seen both sides of the Sun for years.

Bill, I think this is where you're getting confused: Your motor gives 0.9° per step. You want to micro step x4 steps = 0.225° per step. OK with that? your reducing the step size so the angular movement per micro step will also be reduced. Divide 360° / 0.225° = 1600 steps per 360° rotation of the motor. Your Horse shoe is 1219.2 diameter giving 3830.22976... circumference Your pully is 11.9 diameter giving 37.38495... circumference Your motor needs to turn 102.453788... times per sidereal day Total micro steps 102.453788 x 1600 = 163,926.061583.... in a sidereal day There are approx. 86,164 seconds per sidereal day (ignoring decimals) Therefore you motor needs to run at 1.9025 steps per second to drive your 1219.2mm horse shoe at sidereal rate. I think you've got timing and distance measurements crossed. At approx. 2 steps per second that will appear jerky in an eyepiece so you may want to either increase the micro stepping rate, or add a reduction gear to increase the number of steps per second. Old movies used 16 frames per second as a minimum rate as below that rate visual persistence showed flicker. Hence why its common now to use 25, 30 and higher rates to smooth out motion. I hope that helps Francis

Problem there is that you have to re-collimate both ways when you add/remove the secondary assembly.

The observatory stayed closed due to wind last night but it gave me another chance to use the ASI 294MC Pro with my 70-200mm f2.8 Nikon lens with an IDAS NB-1 filter. Orion was shot at the bottom end of the range at 70mm the others at circa 100mm. exposures ranged from 30s to 180s. quite a few subs were lost to clouds but I was pleased with the CEM25P mount's tracking. All subs were unguided which given the windy conditions I felt was good. I need to shoot some calibration subs for these images at some stage. The image of IC1805, IC1848 plus 2017 T2 (Panstarrs) had 60s and 180s subs. The others were 30 and 60secoonds. The grouping of IC405, IC410, M36, M37 and M38 is probably my favourite for the night. Both above were slightly cropped but the Orion image is full frame.

Superb Martin - one of the best images I've seen posted for a long time (even mine!) ✅