quad multi lens imaging camera

[DIYASTRO]

Hi Ajohn, thanks for your likes post &/post.

Yes, transplant of drives is a good way of looking at what I am doing. Simply taking advantage of similar gear systems / ratios and making the mount do much more.

never liked the Meade motor drives I know they work but speed is awful compared to the 800 x RA speed that the Skywatcher steppers produce.

Have had a very busy day, filling a 40 foot container with house stuff and quite a lot of astronomical related equipment. Its surprising when you gather it all together just how much stuff you accumulate over the years.

Did take a little break of sorts and spent some time making the angle plate that supports the DEC motor assembly.

Just a couple of pics to show that.

Will go into detail of the worm wheel assembly for the fork arm when I have time. Just want to try and get this rig finished to a point where I can take a few images before it gets 'contained' within the storage facility!

Boyd

[DIYASTRO]

Once again thanks to those who posted likes.

Very busy today loading the 40 foot container with stuff but did manage to fit the RA motor and main gear assembly.

One other thing that is required is to drill two 10mm holes in the top section of the base assembly near where the fork arms attach.

Couple of pics to show this.

Hope to get some of the wiring looms in the base section some time this week.

Boyd

[DIYASTRO]

Begun the wiring for the RA / Dec drives at last.

You will see from the couple of pics that the reason for the bore on the base bearing mount was to take the wiring loom for the dec and also the dew heater control cables through the centre of the mount.

This I have found much better that coiled cables from the base or orther and allows the fork mount to completely rotate without any snagging of cables.

Hope to get the fork arms on to the base unit in the next couple of days and wire up the Dec motor / dew heater connections.

Boyd

[DIYASTRO]

The fork arms mounted to the base will have to wait till the weekend.

I have however been busy ting out a specific problem with the 'shift' in the various camera images.

It seems that when you rotate a Crayford through 180 deg you loose the concentricity! No wonder I spent so much time re collimating my newts!

Had to think of some way of correcting the very slight offset of the four images and came up with a connection from Canon camera to the Crayford using a 'variable shift' type adaptor.

I looked around for the best canon bayonet connector in terms of widest aperture and good locking capabilities. Eventually decided on the Canon extension tubes used for macro photography.

You have to be a bit selective on where you buy these, some are awful with a lot of flop, I have gone through 3 suppliers and eventually got some good ones.

Using the Canon bayonet and the smallest threaded extension I made 4 aluminium 'adapters' which you will see from the pics I have not threaded for the simple reason that anyone who has done this on a lathe will know that it is so difficult to get a start for the thread so that the component being threaded on it aligns in a set position!

It is important that the 5 long grub screws are positioned so that two ( at the top of the camera avoid contact with the 'flash nose' which protrudes a good way. ( I can see why some people who do mods cut these off!)

Things will become clear when I post some pics of these adaptors fitted to the rig.

The large aperture is really important,.... when the 2" standard fitting goes into the Crayford and the full amount of offset is used on this adapter (about 6mm) you don't want any vignette.

First pic..... Top right is the Canon extension tubes as they come

Bottom right is the Canon bayonet from the extension tube set. You can see the greater aperture over the std canon 42mm type adaptors.

Second pic...... Shows the 76mm x 20mm aluminium blank used to turn the component shown top /bottom left which is the adaptor.

Third pic..... is a rear view of the turned adaptor with the canon bayonet attached.

Fourth pic.... is the front view of the adaptor with the std t thread ring held in place by the five 6BA grub screws. These are set at 72 deg apart and as mentioned, clear the camera flash 'nose'.

Fifth pic..... Shows the adaptor with the std Crayford 2" connection fitting in place

Sixth / seventh pic.... Shows the std 2" at max offset.

last pic... Shows all four adaptors , grubbed and with t thread collar's in place.

This idea may be useful to others so I thought I would post it just now before I continue with the mount construction and wiring.

Boyd

[Horwig]

Eventually decided on the Canon extension tubes used for macro photography.

You have to be a bit selective on where you buy these, some are awful with a lot of flop, I have gone through 3 suppliers and eventually got some good ones.

I can commiserate with you on this one. I use a pentax 67 300mm lens for my widefield rig, and have modified an ebay bought pentax to canon adaptor to mount it on my ccd. I've been growing tired of the variable tilt introduced, this being the worst:

I decided to bite the bulet and buy some genuine pentax extension tubes to vandalise, with this result:

It's all down to the fit of the byonet on the lens, the chinese adaptor was no way as tight as the genuine article

Do we see more of the hammer work?

Keep up the good work

Huw

[DIYASTRO]

Hue,

I thought that some amount of 'hammer work' may have been required but low and behold this weekends efforts have some reward.

Still loading belongings into container and removing various items as I need them, nightmare.

However, did manage to get the Dec motor wired up and after dismounting the rig from the forks for this to be done did a fair bit of tweaking to various bits that required some attention.

Pleased to be able to report that the new drive motors are now operating as goto via the eq6 control panel, moving very smoothly with no need for any hammers whatever!

The new camera adaptors for centring of images also appears to work very nicely, have yet to get the rig outdoors and star test / align the 4 Canon's to the current choice of Guidecam / QHY5l-II.

Next stage is to make up the power supply to the whole rig. At the moment I have three separate 12 volt batts plugged into the control consol. These are more than adequate at 24 Ah each, but have recently brought a couple of 100 Ah batteries and want to make a dedicated supply with circuit breakers and fuses etc.

really looking forward to getting some images very soon, wish I knew how to post a short video on this thread so that other people could see all the rig going through its ra / dec positioning and focus movements etc. Its just so good to be able to press a switch and see it all happen without a pc crashing, stalling or just doing its own thing. Old fashioned I know but it works like a dream!

When ready to take some images, I think they will simply be test shots without filters for the first sequence. They wont be great! even though the four Canon's are astro modded they will need some test runs to find optimum exposures for whatever target.

I do now have four Astronomik CLS clip filters to use so at least I will be able to block any light pollution equally and then see just how different perhaps the images are from the four cameras. I hope they are identical, but in the real world I know that perhaps is wishful thinking. What the tests should be able to do is inform which camera may be best suited to specific filters EG. Ha, Hb, Oiii and Sii etc.

Any advice on this is most welcome.

Boyd

[happy-kat]

Such an interesting project to follow, hope the move goes safely.

[mcolbert]

Boyd would it be possible to load a video to youtube and provide the link in the thread?

michael