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Thank you for the reply Dominic,totally understand the problems underlying with video uploads. I have a Flickr page so can add link to that with a video still as you suggest,mind you getting a video to play correctly on there can be a pain at times as well 🙁
Alun
I just attempted to upload a GIF movie to my image folder and although it played properly it continually flashed in its thumbnail form,it was so bad I have had to delete it before I cause epileptic fits or seizures. Would it be at all possible to include WMV movie format (obviously still within the 2 megabyte size limit)?
Alun
I use a QHY5L-II with an all sky lens (type supplied with ASI120) this gives full coverage of my observatory when running remotely, I use Sharpcap to control the camera.
Last night’s attempt at RS Oph using Lhires III with 35um slit and 2400l/mm grating. Five 300 second subs captured through C9.25.
Alun
Acquired another spectrum last night (12th) using Lhires III and C9.25. Acquisition time of 21 minutes (7x180sec) with 23 micron slit.
Alun
Here is my attempt at RS Oph on the night of the 10th using my C9.25 and Lhires III (23 micron slit) to collect nine 60 second images,chose Vega as my reference star.
Alun
Hi Jack,
No that is from latest download from Atik web page. Glad you got the camera to work.
Regards
Alun
Hi Jack
Are you using a USB hub? If so then try plugging camera directly into the computer,possibility Maxim doesn’t recognise the hub.
Regards
Alun
I agree with Robin in that after replacing the 2400 grating back into my Lhires that the line is indeed a close double. Whilst using the unit with the 1200 grating the line looks to be a single which is why I was puzzled to what was going on.
Regards
Alun
Jack,
I would honestly stop using the modification at this stage before there is any damage done to your Lhires,there is something obviously wrong whilst using the belt and it is twisting the collimator lens support housing somehow. Maybe the threading of the lens housing is different on the newer models of Lhires,possibly a much finer pitch than the original design I don’t know, but if that is the case then the belt mod could be pulling the thread out of the other hence the doubling (distortion) of the lines. Worse case scenario is that the collimator body ends up cross threading 🙁
Regards
Alun
Jack,
Have been looking at the images of your neon lines again and something is puzzling me. They are obviously taken with the same camera but why are they different in that in one image there are three bright lines (plus fainter lines) but in second image only two are visible. Also I’ve noticed along with the doubling effect on the right hand line the fainter line next to it to the right again is still a single line,if doubling effect was caused by the collimating lens being pulled to one side then this line too would be distorted.
Regards
Alun
Jack,
I think the problem lies in the collimator body being loose in its support frame,having a bit of play between the threads the body is being pulled toward the motor side of the instrument and in doing so the line is being pushed towards the edge of the achromatic lens. Hopefully adjustment of the collimator screws will be enough to alleviate the tilt with just enough tension to allow rotation but at the same time keeping the collimator body square to the grating/camera sensor.
Regards
Alun
Jack,
I cannot see your attachment,but still baffled as to what could be causing the doubling of the line. I have not seen the effect in my setup at all. The only thing I can think of once again is that the belt is too tight and placing the lens slightly out of line,maybe my using a much thinner belt places less pressure on the setup. Have you tried using a replacing the belt with a rubber band? Maybe the velcro round the collimator body is the problem (I have just placed belt round the body and have no slippage).
Regards
Alun
Jack
Not had this happen with either motor (Skywatcher or JMI) so not sure what has gone wrong to cause the double lines. Clutching a few straws here, seems there could be the possibility that distortion is somehow introduced between the collimator body and its support. How tight have you got the tension on the belt? Only need a small amount,just enough to allow belt to grip the collimator body and turn it but feels slack if you pinch belt either side of the cog. Have you used the white screws in the support to alleviate any possible side to side movement, lastly did you have to join the belt, if so have you watched the lines as the belt turns and noted where the join is (being as the belt will be slightly thicker in the region of the joint tension on collimator body will increase slightly).
Hope you get it sorted!
Regards
Alun
Received the JMI motor focuser from Rother Valley Optics this morning so got to work attaching it to the Lhires in place of the Skywatcher motor. Just a case of removing a cog and the attachment that goes on a focuser knob and adding a small cog wheel (donated once again from the printer I broke up) to the motor shaft, also had to make up a smaller diameter belt,luckily had just enough printer belt left to do this. Works a treat,not as bulky as the Skywatcher motor and is lighter,just need to add small cover over the cog so as to seal from light and stop dust getting in slot.
Regards
Alun
Jack
Not had any problem in that respect regarding shifting/loosing focus of the neon lines but have read about the possibility of the collimating lens having a loose fit within its cell.
Regards
Alun
Hi Robin,
Yes I have checked in all directions and found no shift at all in the lines. There is a slight shift when using the motor to focus (much the same as if I were manually focusing) but this can be reduced as I stated earlier by adjusting the tension of the screw on the collimator body support opposite to the motor,once the unit is focused everything is stable.
Regards
Alun
Jack
Had a play with my setup last night and found that there was a slight play between the collimator body and its supporting frame so have now replaced the screw (was the one on the motor side) but have it screwed in just touching the collimator body to prevent unwanted tilt but at the same time not adding any force to tighten the turning of the body. All adjustment for tension on the collimator body is carried out by the screw on the opposite side.
I motorized the micrometer shaft so that I didn’t have to touch any of the kit during a session and I also run remotely so comes in handy. But the downside is the speed of the focus motor makes moving the grating from the Hb region to the Ha region painstakingly slow 🙁
Regards
Alun
