david_taurus83

14 hours ago, Jonk said:

She’s a keeper!

First light was going well but the clouds are fighting back now.

Incredible view of Mars at 280x!

Waiting to try and do some imaging at the mo, never tried Mars before.

Thats a beast! I thought that was an EQ5 at first glance!

Congrats!

31 minutes ago, ollypenrice said:

Flats with a CMOS camera need dedicated flat darks taken at the same gain and binning as the flats themselves.

Could you clarify what the top and bottom images are in your post? I'm not sure what I'm looking at.

Olly

The first one is just an STF stretch and the second has had an iteration of ABE.

@mgirdwood
did you apply a full set of calibration frames? Darks for the lights, flat darks for the flats? All at 2x2 as you say you binned?

Guiding will help correct right ascension errors but not declination. The drift is in declination in your stack. Polar alignment is likely cause though if your mount has iPolar it should be good. An error in setting it up?

The AZGTI in EQ mode is mounted the opposite way onto the wedge hence the opposite angle. Its the same on the Star Adventurer wedge. If you were at 45° it would still be 45°. But if you were at 50° you would see the scale read 40°.

Is that what the flat looks like or has it been stretched? It should be an even grey image unstretched. I never had an issue with narrowband flats and I exposed to around 21k ADU with the ASI1600.

Planetary tends to be emmission as well but reflection is mainly broadband. The Iris is reflection for example. You need to be careful when using Ha as Luminance around broadband though. Take Orion for example, if you used Ha as Lum it practically removes the Running Man as that's reflection.

13 pixels at 183mm focal length is a big dither. Try and lower down to 3 to start with and lower the timeout to 60s and the settle to 30. Keep an eye PHD and make sure it can recentre on the guide star within the 30s. If its comfortable you can lower the settle time even more.

54 minutes ago, gorann said:

Great image - I imagined that the M45 would be terrible for the microlensing but apparently not, at least with skilful processing👌

Thanks. That was my first attempt at LRGB (1 hour each) when I got that camera. I think I was lucky though with my WO GT71 and 0.8 reducer as it seemed to tame the microlensing. I tried a Hotech SCA flattener and bright stars gave terrible kaleidoscopic artifacts so I guess its luck of the draw with whatever optics you have. Below is 4 hours of 15 minute Ha subs taken with the WO kit and its just starting to show through on Alnitak. Still well controlled.

4 hours ago, gorann said:

(you can forget doing the Pleiades with an ASI1600)

Its still a good camera.

14 minutes ago, Chasm said:

It’s an eq6-r.  

You could probably get away with that focal length if you binned, just, with guiding. The other issue is field of view. It will be fairly narrow at that focal length. Good for galaxies but you won't fit large nebulae completely into view. Depends on what you want to image really. Give it a go with your current scope and see how you get on.👍

You'd be over sampling at that scale and unlikely to benefit due to seeing and loosing SNR. A focal length of 500 or less would be better for beginning. You could always bin 2x2 though.

What mount do you have?

Lovely scope, wish I still had mine. I took it to my local astro club one night and everyone commented on how sharp the views were. Agree about the locking clamps. The 2" one on mine needed quite a lot of effort to tighten and it usually rotated the focuser in the process. Compression rings with thumbscrews would have been better I think. I did consider this below from TS but never got round to ordering one.

https://www.teleskop-express.de/shop/product_info.php/info/p9781_TS-Optics-360--Rotation---Thread-Adapter---M63-to-M68--M54-and-2-.html

1 hour ago, bottletopburly said:

Ok af1 is the same size Af2 I thought I saw a picture of af3 being bigger .

If anything its smaller. The first AF1 i had didn't have a recess for the small screws that hold it to the bracket. I made it work by drilling the bracket holes a little bigger and ordered a longer belt off ebay (few quid and readily available). When I ordered the AF3 I spoke with Pavle about the fitment issue and he asked for some measurements and pictures. The AF3 arrived with redesigned body and bracket. Fitted like a glove and belt length was perfect. He also sent me a new housing with pc board and bracket for my original AF1 which effectively upgraded it to an AF3 (for a small fee). Great service and great little focuser. Ive seen threads where people have issues fitting the more expensive EAFs and  Sesto Senso units but not a bad word said about the DSD units.

I'm sure I did when I tried a dual rig. Was using APT as well.

Ive recently gone back to mono imaging but im still keeping my modded 6D. Great camera! Low noise and big pixels!

Well I tightened everything up again. Drift is still present so flexure as suggested. I'm hazarding a guess and saying its focuser sag as the drawtube on this setup is around 60mm out at focus. I've measured the drift at approx 1 pixel (2") per 2 x 600s subs. It shifted 20" over 3 hours last night. Not an issue doing 10 minute subs but if I want to go longer it will be. OAG it is then! A shame as guiding has been spot on as well! Need to go tweaking again!

Unlike a DSLR, astro cameras have no blocking filter so will pick up all visible wavelengths plus UV and IR. Mono cameras are used with filters to isolate specific wavelengths, ie RGB, Ha etc. Most of these filters already have IR/UV cut off. With a OSC you will typically be imaging RGB so its recommended to use an IR/UV cut filter to isolate the visible spectrum between 400/700nm. A good LP filter will have IR/UV cut already, like an IDAS or Astronomik CLS-CCD. Then there are the newer dual band filters which will isolate just the Ha and Oiii wavelengths whilst blocking put other wavelengths.

Edit: Also, I think some people get confused with the notion of removing the IR filter from a DSLR and then using an IR/UV cut filter again. The DSLR filter cuts IR (700nm+) and a lot of the Ha spectrum (656nm). The mod just opens up the DSLR to a lot more Ha and using a IR/UV (like a LP filter for example) gives a sharper cut off from 700nm.

Have noticed a couple of items in our own sales section advertised for practically "as new" prices. I suppose someone can charge what they want really.

Just now, vlaiv said:

On Mac? Does Mac have APT package manager?

Ah I missed that bit. Never used a Mac. Is it not Linux?

You need to type it into the command bar. Will be something like this. Been a while since I used it though.

When it dithers does it recenter on the star before the next exposture starts?

How much are you dithering? If the mount has backlash it can take a while for PHD to recentre on the guide star. The Dec axis is usually the worst for this.

45 minutes ago, Stuart1971 said:

They should not move around in the cell, as if they do they will play havoc when making flats...as the dust bunnies will also move around... 👍

Yes that's true. Especially if they are close to the sensor. I was pointing out that its not uncommon for the rings to come loose. They should never be over tightened though.

Olly and Toms?

https://stargazerslounge.com/topic/237263-the-400-hour-image/

Nice! I had an NB1 but didn't get to use it much.