Photosbykev

23 minutes ago, Craney said:

"Planet-burst"   !!!!

Venus is a tad bright compared to the normal stars lol

30+ exposures between 1 and 60 seconds with an ASI533MC_Pro and WO61 refractor. The huge dynamic range makes this a real challenge lol

Comet C/2019 Y4 (ATLAS), currently 160 million kilometers away from the earth and motoring along quite nicely. This short timelapse consists of 100 x 60 second images taken over 150 minutes with a ASI533MC-Pro camera and William Optics Zenithstar 61 refractor captured with APT and post processed using PixInsight Blink for the animation. The bright star lower right is Althiba IV

I'm looking to install a 5 x 2" filter wheel into my system to replace a 2" filter drawer which isn't lightproof.

I'm favouring the Starlight express 5 x 2" filter wheel with T2 threads and the hall effect sensors for precision filter positioning. Any negatives about using this wheel?

regards

Kev

Thank you both for confirming my thoughts on this. I suspect I won't run into any issues with stars in the corners using the small sensor on the ASI533 even if I removed the flattener. As it doesn't change the focal length of the refractor I may as well use the screw adjustment built-in to fine tune the back focus adjustment.

17.5mm - ASI533MC-Pro camera front face to sensor

17.5mm - Starizona filter drawer

so I need around 32.7mm extension + 0.6 or 0.8mm for the filter thickness so approx 32.5mm extension tubes

Kev

I've just acquired a ZWO533MC-Pro to mount on the back of a William Optics Zenithstar 61 refractor with the dedicated PFLAT61A flattener.

I have been using the refractor and flattener with a Canon DSLR and have set the adjustable flattener to 12.9mm when using the T2 mount and the stars are nice an sharp corner to corner.

Anyone using the WO61 with dedicated Flat61A adjustable flattener with a cmos camera? The back focus according to WO is 67.7mm from the rear shoulder of the flattener to the sensor BUT is this with the flattener adjustment set to zero mm adjustment rather than 12.9mm? and can I use that screw adjustment to set the back focus to exactly 67.7mm after fitting extension tubes and filter drawer in the optical path?

regards

Kev

Just need to wait a few months for clear skies lol

19 hours ago, Stretchie_ said:

Hiya

Is that just near the airport?

yes it is

33 minutes ago, cjdawson said:

light leakage or amp glow maybe?

Light leakage doesn't make sense as all the other darks are fine. The canon sensor does have bias noise along the bottom edge but no obvious amp glow. It does look like light leakage but how I'm not sure. I'll reshoot them and check the individual files

Kev

Problem solved but I don't know the cause. Two of the thirty dark images look like this heavily stretched!! New darks required lol

Thanks for all the input folks

Kev

1 minute ago, andrew s said:

I always take darks in the dark just to be sure. Light leaks can also be an issue for flats. 

Regards Andrew 

I shoot the flats immediately after the imaging session with a battery powered flat field panel so it's very dark lol. I think the flats are ok looking at them in PI, certainly not significantly different to other flats I've taken. It's only when I add the darks to the calibration stack that the image gets the curved banding across it in the lower right corner. It isn't the standard Canon sensor banding issue which I normally correct in PI anyway

regards

Kev

16 minutes ago, cjdawson said:

Yep, it's possible to shoot bad darks.  Light leakage would be the first culprit for that.   For a DSLR, you have two places where light can leak into the sensor, first is obviously the lens.  The second less obvious is the viewfinder.

When shooting darks, it's important to make sure that both as properly covered and are not leaking light to ensure that dark frames really are dark, without other influences.   Putting the dSLR in a box, then putting that in a cupboard usually works, however be aware that the temperature of the dark will therefore change, as the camera will get warm and may not have the ventilation needed to keep the temperature down.

Thank you for the input CJ

My darks are normally very good as I do cover the refractor with it's dust cover and then slide a black fabric bag over the end to make sure the objective end of the refractor is  completely blacked out and the camera viewfinder eyepiece is covered with a custom eyepiece blank. The darks and lights sensor temperature were within 2degreesC of each other so I'm struggling with why they should be wrong. I can reshoot them, and probably will, one evening this week when the temperatures get down to around zero ambient and check the second dark set.

regards

Kev

On 03/12/2019 at 11:51, Adam J said:

Its not an easy choice in this price space for OSC right now but I do like the look of these new sensors and am sure it will work very well with the ZS61, congratulations! let us all know how it performs. 

Adam

Delivery delayed two weeks lol At least it will be ready for the next new moon lol

The screen print below is of two images containing identical lights, flats and bias frames. The right hand one has a fresh set of Darks added.

The 240 second darks were shot at the same iso, exposure and temperature on a stock Canon 5D4

I've process the two images with exactly the same PixInsight settings (just background neutralisation,  colour calibration and stf applied to see them) DBE wasn't applied because that would affect the output for this test.

I'm getting these strange slightly curved bands, ringed in the right hand image when I add the darks during the calibration routine

Is it possible to shoot bad dark frames? Previous sets of darks on the same setup have worked correctly so I'm struggling to see why this dark set would be 'faulty'?

The same effect is seen on other data sets as well using this set of darks.

For reference this is what I get with a basic edit from the lights/flats/bias image

regards

Kev

Welcome on board, just up the road in Churchdown

ASI533MC-Pro ordered today to live on the back of a William Optics Zenithstar 61 refractor. Fingers crossed it performs as well as the spec says it will

M42 Orion wide field with horsehead and flame nebulas. Full frame on a stock Canon 5D MkIV camera and WO61 refractor with 61A flattener and IDAS-D2 filter.

Mounted on a belt modded HEQ5 Pro, controlled with EQMod and PHD2, data capture with APT

A few pixels have been trimmed around the edges to remove the dithering edges.

Very basic late night processing from 30 x 240 second and 30 x 30 second lights, plus flats and bias frames, stacked in APP and processed in PixInsight

Size: 5.25 x 3.41 deg
Radius: 3.129 deg
Pixel scale: 3 arcsec/pixel

You don't mention it but if you are using Eqmod as well as Phd2 then the Eqmod default Ra and Dec guide speed settings are way too low at x0.1 The PHD2 recommended value for both is X0.9. If they are at x0.1 then the calibration routine won't be moving enough to complete the routine

Kev

I'm just about to buy a 13.8v bench power supply for powering a HEQ5Pro and all the accessories that go with it like DSLR/Refractor/Hub/Dewstraps etc. At some point I'm going to buy a ZWO ASI 294MC-PRO camera and there isn't any information about it's power supply requirements other than 12v @ 3amps.

Is it ok to run this camera at 13.8v (basically the same as a fully charged unloaded car battery voltage) or does the camera specifically need a regulated 12v supply?

regards

Kev

1 hour ago, reddoss said:

Very disappointed indeed. I was so looking forward to seeing everyone again. 

I may go the Fforest Fields campsite  near Builth Wells instead.

 

Could be busy at Fforest Fields, we're there with the dog this weekend to avoid all the firework noise and I know a lot of other people are doing the same. Forecast is rain and plenty of more rain all weekend

Kev

An update on processing to pull more of the Ha detail out As is always the case more data needed lol

21 minutes ago, Davey-T said:

Nice image Kev, I've got a WOZ61 that doesn't see much use must try to set it up on the Star Adventurer while the other rig is imaging.

Curious about the image scale 9.77, I use a Canon 60Da on mine which I think from memory gives around 2.5 as/pixel presumably the 5D has bigger pixels but your figure looks a bit high ?

Dave

I saw that as well Dave, CCDCalc reports the scale as 3.07arc-sec/pixel which I used for my dithering calculation (6720px wide sensor and 5.36 micron pixel size).

Okay I know why, I resized the full frame down to 2048 pixels wide for Nova to work on  I've corrected the top post

Thank you folks, sounds like just the rear filter needs to come out to take advantage of normal DSLR lens as well as the refractor. I'm not too bother about AF as the camera will be dedicated to astro work so all manual anyway but obviously reaching infinity with dslr lenses is pretty important

Now all I need is just one modification company to reply to my email. 3 companies emailed in the UK and not one reply so far

Kev

1 hour ago, upahill said:

Nice system, looks like the 2080Ti is as good as I've read.

No complaints so far and hopefully will keep me happy for a few months lol