edjrgibbs

5 minutes ago, fifeskies said:

What software is driving your mount.  I use APT and guide with PHD2

 

It does not sound like backlash if its rapid and well off target.

Do you know if its wandering in both Dec and RA

I'm not 100% sure whether its in RA or Dec to be honest. I use Stellarium and Stellariumscope to slew and star align then guide with PHD2 and use APT to image. In PHD 2 the image drifts to the right rapidly straight after slew. A few reverse pulses on the gamepad stop the drift. Balancing issue maybe? 

6 minutes ago, fifeskies said:

Backlash is a likely culprit , this can take a while to settle back again , try leaving it for 5 minutes and it may just catch up with backlash.

I always let my NEQ6 just sit for a short while when I slew to a new target before platesolving to the target.

 

If it drifts for more than 5 mins its likely something else unless your backlash is very large.

Thanks, the problem is it drifts rapidly and completely off target...

Hopefully someone can help. When I slew my NEQ6 it keeps drifting until i apply a couple of reverse pulses on the controller. I'm using it via an eqdir cable to my computer. Any ideas? Could this be a backlash issue?

On 24/12/2020 at 17:15, geeklee said:

Very nice!  What integration and exposure times were they and what else is in the image train there... filter wise I'm thinking?  Dual band or just the straight OSC?  The smaller pixels seem to be a good match at this focal length.

It was about 2 hours of 5 min exposures with darks and bias frames stacked in Siril. I used an Altair triband filter on the QHY183c.

First light. Loving this lens already! QHY183c. with Altair Triband filter. 

Looking for some advice. I'm currently imaging with a QHY183c and Equinox 66. Would an Evostar Ed72 provide any noticeable improvement?  The Equinox 66 is FPL51 glass I think but I can't find any info on the ED72.

Thanks
 

So, got to the bottom of the problem but unfortunately no solution. I was using a newer version of APT on my main computer. I updated on the obsy pc and its cropping the pics slightly. All settings exactly the same. I'm none the wiser why its doing this but apart from having to reshoot all of my calibration files its not a huge issue. Does make multi session stacking problematic though as I can't use any of the old data. 

3 hours ago, david_taurus83 said:

In that case I'd say more subs. Lots of subs. Do you have much LP? This target is a no go for me at Bortle 6. Tried a few times and its just too faint to bring out the dusty stuff without messing it up. Tried mono with an ASI1600 and also with a 6D.

Probably bortle 5. Sounds like the conditions weren't the best... Just need some clear skies to retry!

12 minutes ago, Synchronicity said:

I'm surprised that you have spent twice the time taking darks as lights - more data is always going to improve an image.

Unfortunately due to limited imaging time. I took the darks the following day. 

7 minutes ago, Synchronicity said:

I'll reply from my meagre store of experience.  I have over 3 hours of M31 lights using a QHY10 OSC  (-25c) which have similar noise and from seeing others unprocessed images I'd say yours were quite typical.  A lot of the skill in processing seems to be in reducing noise while retaining faint detail.

I'm surprised that you have spent twice the time taking darks as lights - more data is always going to improve an image.

Hope that helps

Michael

Thats what I thought. Cooler was definitely running. Fits header says

Image #1
    SIMPLE  =                    T / file does conform to FITS standard
    BITPIX  =                   16 / number of bits per data pixel
    NAXIS   =                    2 / number of data axes
    NAXIS1  =                 4656 / length of data axis 1
    NAXIS2  =                 3522 / length of data axis 2
    EXTEND  =                    T / FITS dataset may contain extensions
    COMMENT   FITS (Flexible Image Transport System) format is defined in 'Astronomy
    COMMENT   and Astrophysics', volume 376, page 359; bibcode: 2001A&A...376..359H
    BZERO   =                32768 / offset data range to that of unsigned short
    BSCALE  =                    1 / default scaling factor
    OBJECT  = 'M82     '           / The name of Object Imaged
    INSTRUME= 'QHYCCDCameras'      / The model Camera used
    DATE-OBS= '2020-10-09T20:18:27' / The UTC date and time at the start of the expo
    EXPTIME =                 300. / The total exposure time in seconds
    XPIXSZ  =                  3.8 / Pixel width in microns (after binning)
    YPIXSZ  =                  3.8 / Pixel height in microns (after binning)
    XBINNING=                    1 / Binning factor in width
    YBINNING=                    1 / Binning factor in height
    XORGSUBF=                    0 / Sub frame X position
    YORGSUBF=                    0 / Sub frame Y position
    EGAIN   =                   1. / Electronic gain in e-/ADU
    FOCALLEN=                 1000 / Focal Length of the Telescope in mm
    JD      =     2459132.34966435 / Julian Date
    SWCREATE= 'Astro Photography Tool - APT v.3.33' / Imaging software
    SBSTDVER= 'SBFITSEXT Version 1.0' / Standard version
    SNAPSHOT=                    1 / Number of images combined
    SET-TEMP=                 -20. / The setpoint of the cooling in C
    IMAGETYP= 'Light Frame'        / The type of image
    GAIN    =                  120 / The gain set (if supported)

No one...

Both these photos were taken at -20 on a QHY163c and QHY183c respectively. Stacked with darks. Is the level of noise normal?

Details - QHY183c @ -20 degrees, 20 lights at 300s each, 44 darks 300s each, stacked

Details - QHY163c @ -20 degrees, 10 lights at 300s each, 20 darks 300s each, stacked in Siril

Looking for some help. I've recently got a QHY183c and managed to get an imaging run in yesterday. I then took 2 hours of darks today on a different computer but can't stack the darks with the lights as they are slightly different sized images. Any ideas? Lights are 5544 x 3692 and darks are 5544 x 3684....

Hi

Looking for some advice. I'm considering buy one of the following:

- Altair triband filter

- Altair quadband filter

- Optolong L-eNhance dual band filter

What are the pro's and con's of each and how good are they at filtering out moonglow? I'd be using it with a QHY163c OSC camera.

Thanks

On 12/03/2018 at 16:50, davew said:

I know what you mean ! Look at the sales pages for this adaptor and it doesn't tell you what will and won't fit, that I've seen anyway. It will fit an Ais style lens.

The G adaptor trick at least means you wouldn't have to keep changing the aperture by removing the lens and starting up your camera. Swings and roundabouts I suppose. Double check with Geoptik to see if they do in fact have a proper adaptor.

Dave.

 

Hi Dave

I think this is probably the best/only option short of paperclips which i'm not keen on. Seems odd to sell an adaptor for £90 that can't be used on most current lenses. 

4 hours ago, giorgio_ne said:

Why don’t you create your own aperture mask? In this way you will also avoid diffraction spikes.

Thanks but it doesn't solve the issue. Unfortunately Nikon lenses basically close to their min aperture when taken off the body so f16 on a nikon 50mm afs.

On 12/03/2018 at 15:27, Uranium235 said:

Ok, try removing the lens while the camera is switched on. It shouldn't break anything,  though the camera will report an error. 

I've no experience with nikon lenses, but with canon lenses that have no manual aperture setting, that's the way I would set it (setting up with dslr, then remove).

Unfortunately it doesn't work... Defaults to min aperture on taking the lens off. 

7 hours ago, 1DegreeN said:

Cyclops Optics have custom adapters to connect Nikon lenses to the 163c - https://www.cyclopsoptics.com/cyclops-adapter/cyclops-optics-blade-n-camera-lens-adapter-nikon/ I have their adapter for mounting Canon lenses on the 163M and the quality is very good. I use step down rings to reduce the effective aperture of my Canon lenses and avoid the diffraction spikes that the lens' iris blades introduce. 

Thanks but the same issue with G lenses. There's no way to change the aperture

Thanks Dave. It seems odd to sell an adapter that looks nice but is totally non-functional. I cant really see the benefits of imaging at f16-22...

8 minutes ago, Uranium235 said:

Try this:

Attach the lens to your DSLR camera as normal, set the aperture. Turn the camera off, remove the lens.... done!

Is this from personal experience with a Geoptik adaptor and Nikon G lens? There are conflicting accounts on the internet some of which say the lens defaults to max aperture when the camera is turned off...

Thanks

Looking for some advice. I'm interested in a CCD widefield setup for my AstroTrac. I've got a Nikon DSLR thus want to use my Nikon glass coupled with my QHY163c. If I got a Geoptik Nikon adapter though (https://www.rothervalleyoptics.co.uk/geoptik-nikon-slr-lens-ccd-adaptor.html) how do you set the aperture on a G lens with no aperture ring?

Thanks 

Just completed mine and itching to find out if its improved things or not. I found aligning the RA and Dec worm gears challenging but worked out that I had over tightened one float and massively under tightened the other. I fracture my finger and almost took it off as well but that's another story down to stupidity... All in all the mod was reasonably easy following the instructions. Give yourself a decent amount of time i.e. 4-6 hours of peace and quiet. 

Basically you'll be restricted in exposure length by your mount as its not an EQ mount. Simply put though, sake as many as you can as long as you can and stack them in Deep Sky Stacker. 

Looking at the sharpcap pages it looks like you can take long exposure video. Maybe try 15 second frames and see where you get to.

8 minutes ago, patricmooriamnot said:

Thanks for you reply Peter, I will try taking much longer videos and see how that goes. I still can`t get my head around the stacking bit I have downloaded deep sky stacker so will have to just practice using it. Dark skies. 

Just to jump back in. If you're taking videos its very unlikely you'll get any DSO's coming out in them. Video is for planetary only where you have a really bright object that needs really short exposures but lots of them. DSO work needs much longer images. With M42 you should see something from 15+ seconds. Rotation will be the problem on an Alt Az mount as might stability.