Imaging With Two Cameras at the Same Time

[Hondo]

I had a question about this on the Yahoo site but I figured I would post it here also.  Is anybody using two cameras at the same time?  Does it work for you and what problems have you encountered if any.  I want to be able to dither and Guylain gave me a solution so I sent an e-mail to Hap Griffin to have a cable made as per Guylain's instruction.  Unless I did not understand what Guylain was trying to say it appears that it will not work as per Hap's reply below.

 

"OK.  I see that you are apparently wanting to control two cameras to shoot at the same time.  That will require a special serial cable that includes a diode matrix to separate the two cameras electrically (you just can’t splice two cables into one without camera interaction).  This will be a hand-built cable.  The price will be $60.  How far apart will the two cameras be physically so that I can determine the length required?

 

Hap"

 

[Chrishem57]

I had a question about this on the Yahoo site but I figured I would post it here also.  Is anybody using two cameras at the same time?  Does it work for you and what problems have you encountered if any.  I want to be able to dither and Guylain gave me a solution so I sent an e-mail to Hap Griffin to have a cable made as per Guylain's instruction.  Unless I did not understand what Guylain was trying to say it appears that it will not work as per Hap's reply below.

 

"OK.  I see that you are apparently wanting to control two cameras to shoot at the same time.  That will require a special serial cable that includes a diode matrix to separate the two cameras electrically (you just can’t splice two cables into one without camera interaction).  This will be a hand-built cable.  The price will be $60.  How far apart will the two cameras be physically so that I can determine the length required?

 

Hap"

 

I have tried two cameras with MaximDL in two separate instances.  It almost worked.  I was looking for independent camera operation since I had two scopes a 5" APO F5 and a C9.25 F2.3 on the same mount.  So long as the cameras were not downloading at the same time it was good.  When the cameras decided to download images at the same time the system became unstable.  My solution was to have a second laptop for the second camera.  Laptops are inexpensive and it became the most cost effective solution. It also gives completly independent camera operation.

You probably will want to be able to frame and focus (live mode) each camera independtly, possibly run different exposure lengths.  A single cable to two cameras will not address any of these features.

BYEOS is quite stable on its own but I would expect that two cameras may bive unexpected results.

CAH

[admin]

BYEOS is quite stable on its own but I would expect that two cameras may bive unexpected results.

CAH

 

Well, before releasing this feature last year I ran a test with 2 separate instances of BYE connected to one camera each.  Then created a plan of 1000 x 1 second images on each instance and fired both of them at the same time.  Both instances completed their sequence of 1000 images with no errors; a total of 2000 images.

 

Guylain

 

 

[g__day]

To the original question - I image with two cameras simultaneously.  To do this I run two instances of BYE.  One controls a modded Canon 400D attached to a 100mm APO triplet the other controls a modded Canon 40D attached to a CF 9.25" SCT.  They are mounted side by side.

 

Currently I do not dither via PHD on either instance of BYE.

 

Where I to wish to dither than I would:

 

1. Select dither only on one BYE instance - and that one would be the instances controlling the Camera / scope with the longest exposure time for light frames (normally my largest scope) and
2. Try and align each camera's shooting and cool down idle times between frames so that a dither command won't be issued whilst the second instance of BYE is still exposing a light frame.

So I might start a plan for both cameras saying take 5 shots of 180 seconds, allowing 30 seconds for DSLR cool down after each shot, then run 5 * 360 shots - with 30 seconds of DSLR cool down, then finish with 5 shots at 600 - 900 seconds, same 30 seconds of cool down.

 

I would hope the PHD dither commands occur during the 30 second cool downs!

 

 

 

[s3igell]

I also experimented with Dual Camera Control With PHD Dithering.  I approached my setup much as you are proposing, and posted the results to the BYEOS Yahoo Group.

In general, the difficulty comes with the fact that Dithering and Settling are mostly out of BYEOS Control and don't occur as rigidly timed as desired.  So, there is great difficulty getting the 2nd instance of BYEOS to remain in decent sync with the instance driving PHD.

 

I also pursued the alternative separate Mounts configuration, but we will need to wait for BYEOS v3.1 for the multiple PHD Server config support which should make that setup workable.

 

I've posted a few Feature Suggestions that I'd think might overcome these issues (both the old Yahoo and this Forum).  But, reality is that Guylain's committed to BackyardNIKON (man but we need an acceptable abbreviation for that mouthful), and then the AutoFocusing elements of BYEOS/BN.  (And maybe some time with his family, too...)

[admin]

I'm not sure about the diode thingy, but Jerry Lodriguss split his own cable and added a second camera connection he took from a second cable.  He is the reason why I implemented it that way.

 

Guylain

[Hondo]

Just to confirm, if I get Hap to make the cable then I will be able to control two cameras and dither both cameras as well.  I want to be sure before I spend money on a cable that will not work.

[admin]

Just to confirm, if I get Hap to make the cable then I will be able to control two cameras and dither both cameras as well.  I want to be sure before I spend money on a cable that will not work.

 

Yes, it should if the cable wired properly.  I have implemented this feature for Jerry Lodriguss and he has used it several times in the past.

 

Basically what it does is BYE Instance #1 will trigger the open shutter and close shutter as per the capture plan... and since the signal will be received by 2 cameras both will open its shutter and close at the same time.

 

It is not a perfect implementation like I have said in the past.

 

1) Both cameras must have mirror lock set to the same value (ON or OFF)

2) Both cameras must have noise reduction set to the same value (ON or OFF)

3) Instance #1 will download images as it does does normally (including rename) This is your ACTIVE instance.

4) Instance #2 will download images BUT will not rename... this is because the second instance does not have an active capture plan... it is only there to provide connectivity to the camera.  This is your passive instance.

 

Hope this makes sense.

 

Guylain

[Hondo]

Thanks Guylain for the speedy reply.  I will report back on how this works out.

[Jim]

I'm not sure about the diode thingy, but Jerry Lodriguss split his own cable and added a second camera connection he took from a second cable.  He is the reason why I implemented it that way.

 

Guylain

 

As an electronics engineer I would go along with the idea of isolating the cameras from each other and adding this protection shouldn't affect how the cable works, just reduce the risk of interaction between the cameras or one camera damaging the other due to unexpected voltage or current spikes.

 

Jim

[admin]

I'm not sure about the diode thingy, but Jerry Lodriguss split his own cable and added a second camera connection he took from a second cable.  He is the reason why I implemented it that way.

 

Guylain

 

As an electronics engineer I would go along with the idea of isolating the cameras from each other and adding this protection shouldn't affect how the cable works, just reduce the risk of interaction between the cameras or one camera damaging the other due to unexpected voltage or current spikes.

 

Jim

 

That makes sense.

 

Guylain

[s3igell]

These two Cameras will also need to be mounted Side-by-Side on the same Mount with the AutoGuider for this Split Trigger Cable setup to work.  (But, hopefully that was the intended configuration of this whole thread...)

 

BYEOS, as of v3.0.3, currently only supports communication to a single instance of PHD, although support for PHD2's multiple instances is said to be available in the upcoming v3.1.

 

 

[admin]

These two Cameras will also need to be mounted Side-by-Side on the same Mount with the AutoGuider for this Split Trigger Cable setup to work.  (But, hopefully that was the intended configuration of this whole thread...)

 

BYEOS, as of v3.0.3, currently only supports communication to a single instance of PHD, although support for PHD2's multiple instances is said to be available in the upcoming v3.1.

 

 

Yes, I have added the ability to configure a host in addition the the port number in 3.1 in the PHD setting section of BYE.

 

Regards,

 

Guylain