malc-c

QM have you seen this canon battery power supply?

Astronomiser - Automated Astronomy and AstroImaging Solutions

It's a must have in my opinion I only have one battery and like you say.. Doesn't last long in the freezing cold! Roll on payday

Or just buy a cheap replacement battery, remove the cells and then wire the connectors to an 7808 1A regulator with a couple of smoothing caps on the in and outputs.

QM, In true Blue Peter fashion, with a little bit of foam here and there, a bit of paper tube etc ... but it works a treat !

Well done

Well all those concerns regarding the roof holding up under heavy snow would appear alleviated...

We've had 10 - 12cm overnight and pleased to say the obsy has held up well

Not a bog standard solution there QM, ah do yo get it bog -loo roll

Yes thank you it has a nice Flush fit to it

That last one certainly has an "actress said to the bishop" air about it

:D:D

Theres no turning back now Malcom I belive that if Stan can be successful with his set up on an eq3 I should have the same results with an eq5. I have not added any more weight to my setup by doing this modification and I can also use the webcam for planet imaging.

I also need the GPUSB adapter to run PHD to an ST4 Port and having a dual axis motor kit on my EQ5 is very nice for general observing as well. So really the only expense for me is the GPUSB and the ST4 adapter plus a webcam which I wanted for planets any way.

If this all goes to plan and I can guide with it as Stan is doing then its got to be a step in the right direction ie the money saving direction My GPUSB adapter should arrive by next week from the states then I can do some proper testing and post my results for everyone.

I've got more patience than I have - 10/10 for perseverance

However several things have come out of this conversion that have been very helpful.

5. I now know what PHD (push here dummy) the free guiding software from Stark Labs is all about and that it is free and easy to use.

It has a habit of having a mind of its own. One day it all falls into place, guiding graph is almost two straight lines and it works "straight out of the tin". The next night, nothing changes and PHD is a b***h to calibrate or the graphs resemble the French alps !

7. I have learned a great deal about the ins and outs of setting up a guiding system and had a great deal of help and encouragement from the folks on this forum and made some good friends in the process.

So despite the problems I have faced along the way all those things taken into account it has been a worthwhile project and hopefully the best is yet to come

Can't say fairer than that - to be honest sometimes that's what ist all about...

They were really helpful, and Im glad I dont have to take it back cant fault Rother Vally optics on there customer service polite helpful and genuinely interested, you dont see that very often these days.

Have to agree with that... Ian and Adam often go that extra mile..

Rother Valley say they will change the dual axis kit if it is at faults Just need some one to test theres so I know

I don't think there will too accommodating when they see it's been modified and has an extra hole in the case for the ST4 port

Rik, that seems strange... so in practice it's not slewing at 2x rate in either direction, it's 2x in one and 1X in the other !!

That might also explain the issues QM had and still may have when using PC control as in effect you can't "drive" the mount in that direction.

QM, If it was me I would flex the credit card and simply purchase the Synscan upgrade and save all this hassle

QM,

I would of thought that you should see some movement as you say. Try unsoldering the wires on the back of the handset and see if it does the same ? If it does move then something must of been wrong when the wires were soldered

Guys,

I wasn't recommending those scopes.. just using them as examples of what's available on the market. If you want to know the specs of those scopes simply google (other search engines are available) "finderscope" and look at the images...

To be honest I think this thread is going off course... QM has a stock finder, this can be modified to take a web cam using a suitable adapter that is commercially available. The problem QM has / had was that the self contained auto-guiding system he received as a gift required a mount that has a dedicated ST4 port. Regretfully his EQ5 didn't have that, and the £290 for the goto upgrade was out of his budget. He therefore purchased the dual axis motor drive and performed what is known as the Shoestring upgrade to the handset. The problem he now has is that there is a compatibility issue between the autoguider and modification, hence why he is going down the PC and software route.

My apologies for going over old ground and for being party to taking this thread off topic, even though my intention was to try and steer it back on track !

Hi guys, probably what I’m going to say is stupid but wouldn’t it be possible to use the finderscope with say a 3X Barlow and a webcam to manually guide the scope for 10 mins?

1) unless you have one of the more expensive finderscopes that allow you to use inter-changeable eyepieces (such as the one below)

then I'm afraid your suggestion would not work as you can not attach a barlow to the finders that SW use on their scopes

An alternative is to use something like the £150 Altair Astro 10 x 60 shown below which has an illuminated cross-hair and could be used for manual guiding

An alternative, assuming QM wanted to go down the manual guiding route would be an off axis guider

Hello all,

Has anyone expiremented with the mod? If so what sort of subs were you getting?

Thanks

Austen... have you read this thread completely ???

There's a link to Stan's thread where he has used the shoestring mod to successfully guide his scope using a laptop - together with sample images

http://stargazerslounge.com/imaging-discussion/169572-woohoo-guiding-eq3-2-a.html

Chris, sounds like a good deal... personally, assuming the black mount has the old analogue motors, I would sell the Antares frac and put it with any other cash you have and buy the synscan upgrade for the HEQ5. It will give you a far better platform for imaging

20min guided test exposure (so ignore the vignetting etc)

The Lvi camera plugs into the control unit and then a cable comes out from that directly into the dual axis control unit via the st4 port

Like the attached sketch ?

You mentioned in a previous post that the camera lacks a USB port, and now you have stated that it connects directly to the autoguider box I'm concerned that it will not be possible to use the lvi camera directly with the PC? From what I've seen the camera connects to the autogiuder via a CAT5 cable, which is only compatible with ST4 ports... there appears to be no means of getting the video data stream from the camera into the PC

I guess the only way to really see what is happening, is to view a star through an eyepiece that has the same field of view as the camera and then try and press one of the buttons for half a second and see if the star vanishes. If so then there is little that can be done as the autoguider QM is using appears to have a fixed pulse width, which is too much when used with the shoestring modification.

I have discovered a site where the guy has developed a USB -ST4 adapter for around $60 Autoguider adapter: USB to ST4 output guider

He also makes the HEX code for the PIC micro available too - Not sure how it compares to the shoestring offerings, but I'll keep looking to see if there is something out there that might help.

QM - how does the LVI camera come into the guide equation if it doesn't have any other connections other than the ST4 port ?

As mentioned the QHY5 has both USB and ST4 ports. Data from the camera is sent via the USB cable to the PC. The ST4 cable can be used as a means of transmitting the guide pulses to the mount. Or using ASCOM pulse guiding software on the PC does all the work and sends pulses via the EQDIRECT cable used to control the scope.

let me read up on the shoestring kit - I thought all it did was provide an ST4 port connector with some cable.... If you can hook up a PC then I would suggest using EQMOD and a PC for control

EDIT:

I see you are referring to the GPUSB box for £80 - which then plugs into the ST4 cable you have added to the hand set... Yes cheaper than the Synscan upgrade... by around £100 !

If I understand this correctly guys, QM can't connect a laptop or computer to the EQ5 because he has the basic dual axis motor upgrade. This has no way of interfacing with a PC. The handset that comes with these motors will constantly track at sidereal rate, and using a combination of the switches track at 2x 4x 6x and 8x sidereal when the NSEW buttons are pressed. QM has modified this handset to add an ST4 port so that the output from the LVI autoguider can be connected. This (if my reading is correct) when sending a pulse down the ST4 cable puts voltage on the pads of the relevant switch which the handset interprets as button push and thus momentarily moves the mount at 2x sidereal in that direction. The problem QM is having is that whilst calibrating the target star is moved out of the field of vision, which the autoguider interprets as if the motors are not moving.

Whats required is to either be able to make the hand controller run at normal or 1/2 sidereal rate (difficult) or some how configure the autoguider to send shorter pulses. something which I think is only possible in the MKII version ?

As for the HEQ5, well firstly it has stepper motors with double the precision so can move smaller amounts. The combination of the handset and firmware on the motor board allows for the pulse width to be adjusted to fine tune calibration when guiding. This is more precise when using EQMOD and software running on a PC. Thus if using the LVI with an HEQ5 I have no doubt it would work given all the above.

I can only see two ways forward:

1) - look for a custom stepper controller schematic and build a dedicated controller - but this would need a lot of electronics experience and could be just as costly as the next option.

2) - buy the synscan upgrade, and use the dedicated ST4 port built in. It would be worth having it confirmed in writing that the LVI is compatible with the synscan - just in case

The later would also allow you to control the EQ5 from a computer and thus give you far more flexibility.

I'm also at a loss - I think the problem is that if your motors are tracking at sidereal rate, the minimum setting the handset has is 2x rate. So when a pulse is sent to a direction pad it will either advance that to 2x sidereal in one direction or track it at 1x sidereal in the other, ie sorta -1x sidereal.

Might help you understand the concept and work out whats going wrong with the modded handset

Ok the motor system you have is designed to track at 1x sidereal rate which is 15 degrees per hour. The 2x, 4x and 8x switch, depending what you've selected, makes the motors move the axis at 30, 60 and 120 degrees per hour, presumably when the NSEW buttons are pressed.

So when the autoguider sends a half second pulse (500ms) to the ST4 port, it's like holding down one of those buttons for half a second, which at 2x (the minimum) will make the mount move through 0.004 of a degree (if I got my maths right). My guess is that this translates it to an angular arc that moves the target star too far out of the field of view.

Obviously the idea of guiding is to keep the target star as central as possible with as little movement as possible by sending very small pulses that's enough to place the star back in the centre, ideally without overshooting. As I'm using a different mount, and software to control the scope it's difficult to comment on how the LVI system works, but my guess is that when used with a mount that has a proper ST4 port, the 500ms pulse it would translate into a smaller pulse at motors.

One final thought, when running the calibration was the handset set to 2x - if it was set to 8X that might explain things

I've been gogling around and it would seem that the Smart guider has a fixed pulse of 500mS, which is probably why when calibrating is causing the star to move out of the field of view. Without hacking the firmware I doubt if there is much that can be done.

The SmartguiderII however has variable pre-set pulse durations but even their manual is confusing. The table states 25, 50, 100, 250 and 500 mS but the text below this describing the menu option states allowed values are 30, 60, 125, 250 and 500 ms ????

I find this whole thing really frustrating beginning to wish I had not bothered now and saved up for the HEQ5 mount instead as according to LVI the EQ5 conversion is not going to work with my autoguider and if the speed of my tracking motors at 1x is too slow for all the autoguiders on the market as this guy is telling me then I have just wasted my money time and effort!

Sorry to hear that. Using software such as EQMOD you can set the pulse width from 0.1 to 0.9 which I assume means 0.x sidereal rate. But then that is what's used to control the mount rather than pseudo pressing buttons with the hand controller that cant be set to anything other than sidereal rate ...

Don't know what to suggest other than try and source a second hand EQ5 Synscan unit and use that... or as you say, invest your cash in a secondhand HEQ5 syntrek version

As for the expense, afraid to say that it goes with the territory when developing any modification. My HEQ5 belt mod has set me back a fair bit and that was with the help of another SGL member doing some machining for me.

Glad to hear you're having some success...

I'm confused (easily done to be honest ) The Orion guider has a nosepiece - 1.25" diameter including filter thread Connectors

The LVI also has a 1.25" nose piece and the ccd doesn't seem 40mm further back in the housing

Both also look like a QHY5

And no eyepiece is used for that, it just bolts onto the end of the finder (OK the nose cone on the QHY5 unscrews) but the focus of the optics fall direct on the CCD. The finder is basically a 162mm focal length (f/3.2) achromatic refractor, so provided the CCD can be placed at or within a range either side of the focal length it should in theory focus ?

Dear dear dear... just rang them and the chap was very helpful but the lvi autoguider wont work with it as it wont come to focus.

So much for their statement

The Orion-designed Mini 50mm Guide Scope is a complete and compact guide scope solution designed for use with the Orion StarShoot AutoGuider (sold separately) or similar small-chip CCD autoguider devices.