[Mr Jack Martin]

Alun and Robin,

That’s because I adjusted the micrometer hence the shift in wavelength.

I will repeat this without touching the micrometer an post pics.

I spent Sunday morning fiddling with it adjusting the collimator lens screws but the double line is still there.

When I took the belt off and went back 30 min later it had reverted to a single line !

Thanks for your inputs,

Jack

Essex UK

    

[Mr Jack Martin]

Bill,

Spectra of these objects are difficult to capture, but interesting to see what they contain.

Good work.

Regards,

Jack

Essex UK

[Mr Jack Martin]

Unfortunately the nova appears to be too low down from my location !

Also, the SkyX doesn’t recognise the name V392 Per or its JO or SON designations. I typed in the RA and DEC coordinates instead, it seemed to track there, but was not visible through the finder scope !

Well done to everybody who got data.

Regards,

Jack

Essex UK

[Mr Jack Martin]

Alun,

I have checked the collimator mounting screws all good, but the double line is still present.

I will adjust the collimator lens screws as tight as possible, so that it just rotates and see if that cures it.

Regards,

Jack

Essex UK

[Mr Jack Martin]

Alun,

I have uploaded the pics again.

Regards,

Jack

Essex UK

[Mr Jack Martin]

Alun,

Attached last nights calibration frames taken around H alpha line.

Far right double line with belt on, collimator screws loose to allow belt to rotate lens, same far right single line with belt off, collimator screws tightened and focused.

Any thoughts as to why only 1 calibration line is double and what’s causing this ?

Regards,

Jack

Essex UK

[Mr Jack Martin]

Michael,

Nice spectrum. Good work.

Regards,

Jack

Essex UK

[Mr Jack Martin]

Alun,

The belt is fairly taught to turn the collimator with a Velcro layer wrap around for grip.

The white screws are slackened off 1/2 turn or so from tight to prevent side movement.

The belt is not joined.

I have adjusted both again and will see how it works tonight, and will report back.

Regards,

Jack

Essex UK

[Mr Jack Martin]

Lee,

It does to some extent.

I contacted Essex County Council about turning off the lights from 12 instead of 1 to 5 am stating that it would save them money.

I got a reply from a ‘Customer Services Officer’ with a link to the lighting section and council policy which seems to be set in stone ! 

Jeremy, there is also the issue of the impact of white LEDs on nocturnal animals !

They just don’t get it !!

Regards,

Jack

Essex UK

[Mr Jack Martin]

Lee,

Not sure if this company will have what you want but worth an inquiry;

 http://www.lunaticoastro.com/

Regards,

Jack

Essex UK

[Mr Jack Martin]

Alun,

That’s a neat mod with the smaller motor.

Attached is a pic of my finished mod with the Skywatcher motor.

I tried it out on Sunday night and got double calibration lines l l (don’t have a pic) when I took the drive belt off and focused manually it settled down to give single calibration lines l .

What’s causing this to happen ?

Regards,

Jack

Essex UK

[Mr Jack Martin]

Alun,

The collimating lens worked loose in my Lhires but is easy to fix.

I advise Lhires users to check just in case.

Regards,

Jack,

Essex UK

[Mr Jack Martin]

Thank you all for your input, lots to consider here.

Almost finished motorising the collimating lens, I wrapped a 3 mm wide strip of Velcro round the edge of the lens which grips the belt and works best at fastest rotation speed setting on the handset.

I will test the system and make any changes as necessary as per your suggestions.

Once complete, this should be a more user friendly set up and relatively cheap to convert.

Regards,

Jack

Essex UK 

[Mr Jack Martin]

Peter,

I suggest you try British Astronomical Spectroscopy Software at

https://uk.groups.yahoo.com/neo/groups/astrobodger/info

Hope this helps,

Jack

Essex UK

[Mr Jack Martin]

Alun and Robin,

Thanks for your advices.

I will take measurements as suggested.

A tear down sounds like a good idea which should sort any instability problems.

1. There is a problem with wavelength shift any idea what’s causing this see attached.

2. The calibration lines are in focus at start and can go out of focus at the end of the session.

Both problems occur on and off, before motorising the collimator lens adjustment, I don’t expect that to make any difference.

Has anyone else had these problems ? if so how did you overcome them ?

Regards,

Jack

Essex UK 

[Mr Jack Martin]

Alun,

Which side did you remove the screw from the collimator body ?

Regards,

Jack

Essex UK

[Mr Jack Martin]

Alun,

Thanks for the link, some good modifications.

I can put one cover back on once I have got the belt gripping properly, will try putting o rings over the lens thread.

The Lhires is contained in a film changing bag which should keep dust and light out. 

A question, as I do not operate the spectrograph remotely is there any point in motorising the micrometer arm ?

Regards,

Jack

Essex UK 

[Mr Jack Martin]

Alun,

I found a belt that fits from RS Components;

https://uk.rs-online.com/web/p/timing-belts/7785064/?sra=pstk

Saves cutting and gluing.

The belt around the lens keeps slipping, but sort of works, I will try some Velcro or o ring. 

Regards,

Jack

Essex UK

[Mr Jack Martin]

Alun,

Found this on Robot shop is it suitable ?

https://www.robotshop.com/uk/makeblock-1m-open-end-timing-belt.html?gclid=EAIaIQobChMIk8H1oLuA2gIVzbXtCh2oZgh0EAQYBCABEgIlgfD_BwE

Regards,

Jack

Essex UK

[Mr Jack Martin]

Alun,

Thanks for your advices. and pictures.

Today I installed the Skywatcher motor to the Lhires.

I have yet to get a suitable drive belt.

What is the yellow attachment on the motor shaft ?  

Regards,

Jack

Essex UK

[Author]

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